Final Report Summary - DRIVE4EU (DRIVE4EU: Dandelion Rubber and Inulin Valorization and Exploitation for Europe)
Executive Summary:
Natural rubber (NR) is an essential renewable material for more than 40,000 products essential to building, medicine, transportation industries. In many applications NR cannot be replaced by synthetic rubbers. At the moment NR is harvested exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in South East Asia. NR consumption is forecasted to increase significantly and will increase from 11.2 MT in 2012 to 16 MT in 2020, pushing upwards market prices.
Increasing NR demand can only be complied with by increasing the acreage of rubber tree plantations, but this may be hindered by sustainability issues, including sustainable land use (deforestation), availability of cheap labour, and control of potentially devastating fungal diseases (South American leaf blight). For their NR supply Europe fully relies on imports. Considering the future market developments and related sustainability issues, European rubber manufacturers are urgently looking for resource diversification.
In an earlier EU project on natural rubber, we already demonstrated the quality of natural rubber produced by Rubber dandelion (Taraxacum koksaghyz, TKS). An advantage of TKS is that up to 40% of its root biomass comprises inulin. Inulin is a polymer of fructose, an excellent resource for furan type chemicals and polymers. The main objective of DRIVE4EU was to turn TKS production into a valid business case by developing concepts for valorising rubber and inulin.
TKS is a wild, non-domesticated plant, with a relatively low yield potential. EU-PEARLS resulted in good quality (dry) rubber and two car tyres, and a proof of concept of the rubber extraction process, plus the development of breeding tools for TKS. All essential key elements of the whole production process were in place: the quality of the rubber is good, the extraction method has been sorted out on lab scale, the first breeding tools were set up. The only part that will enable the real demonstration of the viability of Rubber dandelion as new European natural rubber and inulin source, is the scaling up of each individual step in the production chain. This means that in this follow-up demonstration project we needed to scale up all levels in the production chain of NR from TKS, and to valorise as much as possible of the TKS biomass in order to make an economical feasible production chain. In DRIVE4EU TKS cultivars (prototypes) have been developed that produce more total biomass and more rubber. We have optimised the agronomical conditions for growth and seed production (both technical and non-technical) and developed technology for harvesting on large scale, and designed machinery for optimal extraction of the two products, rubber and inulin. The quality and properties of rubber and inulin in different applications was investigated and turned out to be of good quality. Finally, an economic analysis of the whole rubber production chain was made.
The main goals of DRIVE4EU were: (1) plant genotypes with high root biomass, high rubber and inulin yield, (2) seed batches for agronomic tests and large scale demo field trials, (3) new agronomical methods to optimize cultivation and harvest of Rubber dandelion, (4) ecological analysis of the gene flow and competition between cultivated and wild dandelions leading to optimal planting protocol to prevent in- and outcrossing, (5) optimised extraction and purification protocol and machinery of valuable products from TKS-roots: rubber, inulin, and rest material, (6) demonstration of an economic viable and robust production chain and end product uses. All these goals have been reached, showing the success of the DRIVE4EU consortium and the opportunity for Rubber dandelion as new sustainable rubber and inulin crop for Europe.
Project Context and Objectives:
Introduction
Natural rubber (NR) is a unique biopolymer that is essential for the building, medicine, personal care and transportation industries. In many applications, NR cannot be replaced by synthetic – petroleum – rubber (SR), because the high molecular polymer length of NR cannot be matched by SR. At the moment, NR is harvested almost exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in Southeast Asia, meaning that Europe largely depends on imports from Southeast Asia.
The world market for NR increased from 4.4 Mton in 1985 to 11.2 Mton in 2012. Based on forecasts of the International Rubber Study Group (IRGS), NR consumption is expected to reach 16.5 Mton in 2020, with the tyre industry accounting for 12.6 Mton and general rubber goods industry for 3.9 Mton. Since NR cannot be replaced by synthetic rubber, access to natural resources is thus becoming increasingly important.
In the current situation, increasing NR demand can only be complied with an increasing acreage of rubber tree plantations. However, the rubber tree suffers from a number of threats and drawbacks:
• The rubber tree plantations have very limited genetic variability, which results in threats by pests and disease, most notably South American Leaf Blight (SALB). Rubber production is geographically limited to tropical zones mainly in South-Asian countries (80% of which in Malaysia, Indonesia, and Thailand). For now, SALB has been kept out of Asia by a strict quarantine. However, SALB and other plant diseases are threats to a strategically important material.
• Rapid increases in rubber demand, especially in rapidly growing large economies such as China and India, have caused volatile prices. Moreover, existing rubber tree plantations are being replaced by palm oil plantations. In the long term, production from the rubber tree may not be sufficient to cope with increasing demand.
• Climate change threatens agriculture worldwide. Southeast Asia is one region predicted to be especially vulnerable, as detailed by the Economy and Environment Program for Southeast Asia (EEPSEA). High rubber prices are e.g. due to exceptional drought in Southern China and Northern Thailand, Laos, and Vietnam, while rains disrupted tapping in Indonesia and Thailand. These events may or may not be early manifestations of climate change, affecting natural rubber production, but are at least illustrative of possible climate related risks.
• Rubber tapping depends on cheap manual labor, leading to increasing production costs and difficulties to hire tappers as the producing countries develop their economies.
The above shows very clearly that, in order to reduce the dependency of the European industry on the rubber tree and on Southeast Asia, alternative sources of NR should be developed. Diversification of NR sources will strengthen the competitive position of Europe.
EU-PEARLS, which finished in 2012, was a successful FP7-project (coordinated by DLO) aiming at the development of two alternative NR sources for Europe. This research-project investigated the possibilities to produce rubber from 1) guayule and 2) the Russian dandelion (Taraxacum kok saghyz, TKS). It was shown that both crops are able to produce high-quality rubber, but they differ considerably in breeding, cultivation, harvesting and rubber extraction methods. TKS showed the best potential for industrial application, because of the following advantages:
• The rubber from the roots of TKS was demonstrated to produce a rubber which matches the quality of the Hevea rubber, which provides opportunities for high performance products in building and transport sectors.
• TKS can be grown in temperate climate regions, in particular East-European regions with a very large though still under-exploited agricultural potential.
• TKS is an annual crop, which will allow yearly harvest of the full biomass, thus permitting to generate additional economic value by valorising other biomass components. Moreover an annual crop can be plugged in existing crop rotation systems.
• TKS is much easier to breed: because of the short reproductive cycle (2-3 new generations per year), low diploid number of chromosomes and the possibility for sexual reproduction.
• TKS can be easily harvested: existing chicory root harvesting machines can be used.
• The TKS root biomass comprises, next to 10-15% NR, up to 40% inulin. Inulin is a polymer of fructose, an excellent resource for furan type chemicals and polymers. Inulin can be extracted using hot water (allowing a biorefinery process that can be operated without the use of organic solvents).
One of the aims of EU-PEARLS was to increase the productivity and the quality of TKS rubber. This aim has been achieved and EU-PEARLS resulted in good quality (dry) rubber, proof of concept of the rubber extraction process and conversion of NR in two car tyres. Another result of EU-PEARLS was the development of breeding tools and the formation of hybrids between TKS and more vigorously growing dandelion species. For TKS, proof of principle was obtained on an efficient extraction process for rubber on lab scale and on small pilot scale. Crude rubber samples from TKS were used to produce the first sets of (two) car tyres which are currently subjected to an extensive testing program. The first result showed that some aspects, e.g. wet grip of the tyres were equal or even superior to conventionally produced tyres.
As we now know, within the extraction-process there is also room for the extraction of valuable by-products (inulin). Inulin is the main (even more abundant than NR) biomass component of TKS, and an excellent resource for green chemicals. Inulin can very easily be hydrolysed into fructose. Fructose in turn is the most efficient starting point for the production of 2,5-furandicarboxylic acid (FCDA), a biobased alternative for the ubiquitously used petrochemical terephthalic acid (TA).
Taraxacum koksaghyz (TKS)
TKS is a wild, non-domesticated plant species, and therefore has as relatively low root (the main source or NR) and rubber yield. TKS was cultivated on a large scale in the Soviet Union between 1931 and 1950, as well as in the United States, the UK, Germany, Sweden and Spain during World War II as an emergency source of rubber when supplies of rubber from Hevea brasiliensis in South East Asia were threatened. During this time period, the highest yields achieved in the U.S. were 110 kg of rubber per hectare, while the USSR achieved yields of 200 kg of rubber per hectare. With the conclusion of World War II and the return of affordable Hevea brasiliensis rubber, the majority of T. kok-saghyz programs were discontinued.
When the EU-PEARLS project was started, TKS had not been grown for more than 50 years and worldwide germplasm collections were lost or contaminated with other poor rubber producing dandelion species. New true TKS germplasm was collected in two expeditions to eastern Kazakhstan for use in EU-PEARLS.
DRIVE4EU
The DRIVE4EU-project was a logic continuation of the successful EU-PEARLS project. In order to bridge the gap between research and the market, and to commercialise the research results, DRIVE4EU aimed to demonstrate the technical and economic feasibility and potential of TKS. The demonstration included two important innovations:
• Scaling-up of each individual step in the production chain: breeding, seed production, cultivation, extraction of raw material (NR and inulin), and conversion of raw materials in products.
• Extraction of inulin as valuable compound (besides NR). This concept was not adressed in the EU-PEARLS program, but newly introduced into DRIVE4EU. The reason is that economically sustainable production of NR by TKS, also requires the valorisation of additional biomass components.
All essential key elements for this demonstration project were in place: germplasm had been collected and multiplied, the breeding tools were set up, the first hybrids were produced, the NR extraction method was sorted out on lab scale and the quality of the TKS rubber that has been found was very good. Though DRIVE4EU introduced a seemingly new concept - inulin as building block for green chemicals - all essential knowledge to extract and valorise inulin as the second main biomass component was available in the DRIVE4EU-partnership.
The strategic objective of the DRIVE4EU-project was to establish, and demonstrate the economic validity of a European production chain for natural rubber (NR) and inulin as building block for green chemicals, using Russian dandelion (Taraxacum koksaghyz, TKS) as a production platform.
In DRIVE4EU we continued developing TKS cultivars (prototypes) that produce more total biomass and more rubber. We optimised the agronomical conditions for growth and seed production (both technical and non-technical). We developed technology for harvesting and increasing the extraction efficiency of the two main products, rubber and inulin. Hybrids produced in EU-PEARLS were used for this, including the developed breeding tools. Hybrids were grown at different locations in order to investigate the ‘genotype x environment’ interactions. The quality and properties of rubber and inulin in different applications has been investigated. Finally, an economic analysis of the whole rubber production chain was made.
The economic optimization of the cultivation of TKS will make the EU less dependent of NR imports (resource diversification) and has the potential to create many new jobs in Europe. DRIVE4EU will boost the European economy, because it provides the EU with a valuable business case to create extra economic value from available land.
Specific objectives:
The specific objectives of DRIVE4EU were:
• To create TKS plants with higher productivities and to muliply new genotypes via seeds (WP2).
• To produce enough seed lots for large production fields (WP2).
• To develop improved agronomical methods for optimized cultivation (WP3).
• To establish the best methods to harvest and store TKS-roots (WP3).
• To gain knowledge on gene flow and competition between cultivated TKS and wild dandelions (WP4).
• To design a biorefinery process that optimally uses all valuable products from TKS-roots (WP5).
• To demonstrate the quality and applicability of NR and inulin by developing prototype products from these biomass components (WP6).
• To proof the economic viability of the TKS-business case (WP7).
• To inform industry about the demo-results and raise awareness among the wider European public (WP8).
The economic objective of DRIVE4EU is to prove the techno-economic viability of NR from TKS as a business case and to stimulate the commercial exploitation of the project results.
The political objective is to make the European Union less dependent on imports from Southeast Asia, thereby increasing the competitiveness of Europe and boosting the European bio-economy.
Industry-driven
This demonstration project was primarily driven by industry: several European industrial organisations have recognized the potential of the TKS as a new and European source for NR. A competitive, domestic source for the production of NR will substantially decrease their dependence on imports from Southeast Asia.
The development of a solid and viable business case in WP7 will facilitate the establishment of a successful, large scale production chain. The industrial activities that together represent the whole TKS production chain. They coincide with the WPs 2, 3, 5 en 6 of DRIVE4EU.
The industrial partners of DRIVE4EU, who are the initiating and driving force behind the project, were represented in three of the four steps of the production chain:
• KeyGene NV (NL); breeding and biotechnology (WP2).
• Syral S.A.S. (FR); extraction and processing inulin and fructose based products (WP5).
• GEA Westfalia Separator Group GmbH (DE); extraction apparatuses (WP5).
• NETSZCH Feinmahltechnik GmbH (DE); machinery for NR extraction (WP5).
• Apollo Tyres Global R&D B.V. (NL); conversion of NR into car tyres (WP6).
• MITAS a.s. (CZ); conversion of NR into off road tyres ( agro, industrial, moto, small aircrafts etc.) (WP6).
• Trelleborg Sealing Solutions Kalmar (SWE); conversion of NR into polymer-based building products for sealing, damping and waterproofing (WP6).
With respect to the crop cultivation (WP3), no industrial partners were currently involved, but we expect that this activity will be taken over by industrial parties after completion of the DRIVE4EU-project.
DRIVE4EU is concerned with the development and application of ‘industrial biotechnology for the production of high-value products’, in this case NR and inulin. In DRIVE4EU, the research results of EU-PEARLS were further developed, scaled-up and demonstrated in order to stimulate the ‘commercialisation of these research results’. This project will ‘bridge the gap between research and market, while keeping a pre-compeptititve nature’. The high representation of industry enures that the ‘EU-support is primarily aimed at industrial participants’, whereas the research participants were more supportive. The project included a ‘detailed economic viability check’ and the development of an exploitation plan. The project contributes to the European competititveness by introducing a viable, biotechnological alternative for NR, which can be produced in Europe.
Project Results:
Background
Natural rubber (NR) is an essential renewable material for more than 40,000 products essential to building (adhesives, sealants), medicine (gloves, tubing), and transportation (matting, tyres) industries. In many applications NR cannot be replaced by synthetic rubbers. At the moment NR is harvested exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in South East Asia. Worldwide NR consumption is forecasted to increase significantly. At the moment the EU is completely dependent on imports of NR.
The successful EU-PEARLS project, which finished in 2012, demonstrated the viability of a new NR producing concept: Russian dandelion (Taraxacum koksaghyz , abbreviated TKS). Not demonstrated in the EU-PEARLS project, but of equal importance in the construction of the TKS business case, is the fact that TKS is also a promising new crop for biomass derived building blocks for the chemical industry via the production of inulin.
The strategic objective of EU-DRIVE was to demonstrate the economic potential of a European production chain for natural rubber and inulin as building block for green chemicals, using TKS as a dual purpose production platform.
To reach the objective a strong consortium of eight industrial partners and five research organisations from eight EU countries and Kazakhstan was constructed with a very broad background from bioscience to the rubber industry.
The main deliverables of DRIVE4EU were: (1) plant genotypes with high root biomass, high rubber and inulin yield, (2) seed batches for agronomic tests and large scale demo field trials, (3) optimized cultivation and harvest methods for TKS, (4) ecological analysis of the gene flow between TKS and wild dandelions, (5) scaled-up and optimised extraction and refinery protocol for TKS NR and inulin, (6) testing and application of TKS NR and inulin in end product uses, (7) demonstration of the economic viability of the TKS production chain for NR and inulin.
1. Results on plant genotypes with high root biomass, high rubber and inulin yield
The approach to the Taraxacum koksaghyz (TKS) improvement reported in this treatise is a repeated crossing with TKS as a mother plant and with related polyploid agamospermous dandelions as pollen donors. The acquisition, characterization and a detailed analysis of several pollen donors, and the first series of crosses highlighted two pollen source as the most promising germplasm. It was T. brevicorniculatum (TB), a triploid apomict with two genome copies of TKS and one from unknown source, and a 202PEC sample, a tetraploid also closely related to TKS. We used a sophisticated system of cultivation and crossing techniques, with early characterization of progenies by means of FCM, rubber and inulin quantification. The rubber quantification is based on a newly adjusted technique suitable for very small samples of root tissues. All the classes of hybrids and wild plants were analysed for both rubber and inulin, and summary data are given. Two hybrid strains were evaluated as most promising ones: one of the TKS x TB parentage, with a high inulin content, the other of the TKS x 202PEC parentage, the latter with the potential of a relatively high rubber producer. These two stable agamospermous hybrid lines share the attributes desirable for a rubber plant: high biomass, agamospermy, permanent hybridity and polyploidy of the alloploidy type, no need for pollination. Moderate rubber amounts in the selected lines vary, mainly because of the sensitivity of the quantification method, and regularly exceed 8-10 % DW. Pending the results of field trials, this part of the project succeeded in developing a basis for the new rubber crop.
Since the 1930s, Taraxacum koksaghyz is considered as a possible alternative source of natural rubber (Kirschner et al. 2013) to replace Hevea brasiliensis (Euphorbiaceae). Along with the classical improvement programmes developed for T. koksaghyz (TKS, for summary, see Ulmann 1951), there is a long-term programme involving hybridization of TKS with related congeners. Taraxacum koksaghyz as a crop plant has a number of unfavourable features that are to be improved: low biomass, a complicated root morphology, very variable rubber content, a need for pollination / insect pollinators etc. There are three basic philosophies for the improvement of a rubber producer based on TKS, if we disregard the GM. First, it is a continuation of the standard selection programme (with selection focussed on biomass, root morphology, rubber concentration in latex and the flowering time). The second approach is based on the experimental hybridization between TKS and another diploid sexual congener, e.g. sexual T. officinale, with molecular characterization and selection from within hybrid progenies and further backcross generations, in order to get a sexual cultivar with desirable attributes. The last approach again involves repeated experimental hybridization, this time with a range of agamospermous polyploid congeners, in order to get an agamospermous polyploid hybrid with permanent heterosis, i.e. with high biomass, reasonably high rubber and full seed set without the need of pollination. The latter approach was used within the WP2 of the DRIVE4EU project.
TKS is a plant with relatively low biomass, a necessity of sexual reproduction in the diploid, substantially branched roots, and a narrow ecological amplitude. The hybridization programme was set up to obtain hybrids with the following attributes: high biomass (a result of extreme levels of heterozygosity in polyploid hybrids, permanently fixed by agamospermous reproduction), taprooted general habit, agamospermous reproduction (stabilized diplospory, Taraxacum type, pollination not required), allopolyploid genome (permanent heterosis), and a wider ecological amplitude (as a result of several copies of metabolic enzymes with a range of reaction optima). In view of these rather limiting conditions for the paternal material, some of the pollen donor taxa were selected as priority sources of paternal germplasm, after excluding several others, see Material and Methods. We therefore limited our advanced experiments to two pollen donors: Taraxacum brevicorniculatum (TB), a triploid apomict characterized by relatively low to moderate rubber content, high biomass, triploidy and the genome composed of two TKS genome and one unknown one (Kirschner et al. 2013; since the EU-PEARLS, a number of papers using TB as a model rubber plant appeared but these are not cited here as they are outside the scope of the present report). The other pollen donor is an undescribed agamospermous tetraploid, also parapatric to TKS under natural conditions, with a rubber content slightly higher than in the latter polyploid. The main aim of the crossing programme therefore was to obtain a rubber productive, vigorous, polyploid agamospermous, high biomass hybrid.
From the extensive hybridization programme we obtained several hybrid lines with a remarkably high rubber percentage in roots. These are now analysed in other partner's labs to check the existing rubber figures and to characterize the hybrids from the genomic viewpoint. Two of the selected hybrid samples share the following desirable attributes: (a) high biomass, (b) rubber content comparable to or slightly lower than that of TKS, (c) polyploidy, and (d) agamospermous reproduction. Thus, this part of the IBOT participation in the project succeeded in developing a basis for the new rubber crop.
The first line of the TKS x TB parentage is also enormously high in inulin (often over 60% DW) but its rubber performance is to be tested under standard agricultural conditions. The other line, selected from multiple progenies of the TKS x 202PEC parentage, also requires standard field testing. Both require further analysis as to their root morphology and biomass variation.
The hybrids have a potential of 2-5 times higher biomass, so that the overall rubber yield is expected to be reliably higher than that of TKS. The hybrid lines also do not suffer from the possible lack of pollinators (TKS is entomogamous).
2. Results on seed batches for agronomic tests and large scale demo field trials
KeyGene has multiplied its EU-PEARLS seed stock of wild TKS to provide seeds for the agronomy plots (WP3) and the large demonstration fields (WP6). At the start of DRIVE4EU approximately 2500 seeds were available. These seeds are used for seed amplification in the seed nursery. The number of seeds available for agronomic tests were limited in the first years due to the limited multiplication rate.
During the seed production we ran into several issues as drought, early flowering (prior to the availability of pollinators), hail storm and flooding. In the end most seed multiplication has taken place in a controlled greenhouse environment. In addition seed harvesting methods were not yet developed; simple but effective methods were developed to harvest the seeds. Seed processing was executed at the KeyGene seedlab and by outsourcing it to experienced service providers. Seeds provided to WP6 were for a part primed (and pelleted).
Seeds were provided to the WP6 partners mostly in accordance to the deliverable. However a delay occurred in 2016 due to bad weather conditions. In total, for large scale demonstration fields for WP 6 5000 seeds were provided at month 16, and 750000 at month 28 and the same amount at month 40.
Seed production started at first in combination with the breeding program and was continued from 2015 onwards in shielded fields using bumble bees or naturally available pollinators of TKS germplasm, and in greenhouses using bumblebees. Inflorescences were collected and seeds were processed and cleaned. Seed production from the TKS germplasm stock available was executed in 2015 at two different open field locations. This concerned small patches of approximately 600 plants each in Achterberg (open field) and Elburg (mesh tunnel). Seeds were harvested manually successfully. The locations had different soil types.
In 2016, seed production from the TKS germplasm available was executed at two open field locations. The locations had different soil types and differed in size. One location was an fenced open field of 10.000 plants (Overloon), one had an open field at a small farm (600 plants, Achterberg). The open fields used both natural occurring pollinators in 2016. The fields both suffered from severe weather conditions in 2016. The Overloon field, harbouring the large production field, got flooded in June 2016 and the location as well as the plants have to be regarded as being lost. The field in Achterberg suffered from heavy rain earlier in the year. As the soil kept being wet a large number of overwintering plants got lost. This location was abandoned at the end of 2016.
- In order to reach the targets a new greenhouse location (Huissen) was started up in early 2016. In this location a number of tents were put up in order to grow the lines separately without intercrossing between selections. In order to produce enough seeds, seeds were sown on plugs. Young plants were vernalized and only good plants were grown in the seed production tents. In total 5 tents each harbouring 1000-5000 plants were used. The greenhouse seed production made use of bumble bees successfully. Material for specific traits was harvested separately (vernalisation need, leaf shape). These selections had been top-crossed. The seeds were partly being processed using an acquired seed brushing machine, sieving, and subsequent cleaning using a seed air separator. Seed harvesting is partly done with a self-made seed collecting device.
- Due to large losses in the open field productions additional seed production has been started up in June 2016. A total of 10,000 seeds of two selections were sown for seed production in large tents (200 m2) in the Huissen greenhouse. In total 18,000 plantlets have germinated and are vernalized to induce flowering. The seed production was successful in spring and summer 2017.
Those first seed batches were cleaned at the KeyGene seedlab and partly by outsourcing it to experienced service providers due to the high volume. Due to the high volume material available grading of the seeds was possible (on seed caliber) thus higher quality seed could be provided to WP6. The material was stored, and sufficient material was available. Finally, only the Huissen greenhouse location was continued after 2016. Plants remained in the soil for subsequent harvesting.
- Priming and pelleting of seeds was successful as germination rates increased dramatically. A partnership with Incotec safeguarded high germination rates.
The seed batches delivered to the partners were:
• ~400 k primed/pelleted seeds were provided in June 2016
• ~750 k primed/pelleted seeds were provided in May 2017
• ~100k unprimed seeds were provided June 2017
3. Results on optimized cultivation and harvest methods for TKS
Summary
Although Taraxacum kok-saghyz was cultivated in the Soviet Union and other countries until the 1950’s, the agronomy of the rubber dandelion using current technology was rather unknown at the start of the Drive4EU project. During the project we explored and demonstrated the consecutive steps in general root crop production: sowing (bed preparation, densities, sowing date), fertilization, herbicide treatments, harvesting (harvest machines, harvest date) and storage, in Belgium, the Netherlands and Kazakhstan. Four years of setting up TKS production fields revealed that TKS agronomy should rely on sowing in late spring with naked or pelleted seed. Ridges or raised beds are preferred as these promote root formation and yield longer roots. Plant densities should be high but depend on the sowing and seed bed preparation. Test with densities of 375k/ha yielded the highest root yield (3.3 ton DM/ha). TKS has a low fertilizer demand (50 to 70N) and herbicides to be used in TKS were identified. These need further testing for approval. Harvesting experiments showed that machinery should be adapted to the required large digging depth and the branched root shape of TKS, in order to reduce root damaging. Current (mechanical) cleaning devices on harvesters are not well suited for this root shape, leading to high amounts of tare in the harvested product. An additional cleaning step between harvest and bio-refinery is at this moment still required. Breeding of TKS towards a large tapered root and cultivation on ridges could improve the harvesting process. The Drive4EU consortium made the step from field trials at small scale (100 – 200 m²) to large scale (4 ha). Further yield enhancement is expected through improvement at the level of field germination and harvesting. This can be achieved by agronomic innovations but also at the breeding level such as working on root morphology to enhance the harvest efficiency.
Introduction
The first step which was explored was the installation of the field. Current tap root crops such as cichory are grown on ridges, which promotes the growth of a straight tap root without branches. However sowing on ridges implements a lower plant density than compared to flat field sowing. During the project we compared the tap root shape when grown on ridges versus flat field.
TKS agronomy preferably relies on direct sowing as planting pregerminated seedlings is too expensive. To secure high plant densities, one has to rely on good field germination of naked seed. If naked seed is not suitable for direct sowing with current technology due to various reasons such as incompatible seed dimensions for mechanical sowing, low field germination due to lack of moisture for a sufficient time or necessity of light, ... , naked seeds can be primed (break-down of dormancy) and/or pelleted to allow direct sowing with current technology and conditions. We investigated the advantages of pelleted and/or primed seeds versus naked seeds.
A second aspect of TKS agronomy is the fertilization and weed control. As TKS in not yet a registered crop, no registered herbicides are available to be used in TKS production. We tested a range of herbicides for their compatibility with TKS crop production. The tested herbicides include pre and post germination herbicides.
Finally, the crop has to be harvested and stored in such a way that the bio-refinery can process the harvested roots for rubber and inulin extraction. The scale-up of the bio-refinery revealed some burdens to be solved at the level of harvest and post-harvest methodology. Especially the presence of above ground material and soil in the harvest hampered an efficient bio-refinery system. Therefore, different harvest and post-harvest treatments such as haulm killing, washing, drying and sieving of roots were tested in order to improve the quality of the harvest for bio-refinery purposes.
In the last years of the project we made the step from small scale field trials (6m² plots) up till large scale demonstration fields (up to 4 ha), which allowed also to scale up the machinery (planting, weed control, harvest, cleaning of harvest, ...).
Conclusions
Four years of setting up TKS production fields revealed that TKS agronomy should rely on sowing in late spring with naked or pelleted seed. Ridges or lifted beds are preferred as these promote root formation and yield longer roots. Plant densities should be high but depend on the sowing and seed bed preparation. Test with densities of 375k/ha yielded the highest root yield (3.3 ton DM/ha). TKS has a low fertilizer demand (50 to 70N) and herbicides to be used in TKS were identified. These need further testing for approval. Harvesting machinery should be adapted to the required large digging depth and the branched root shape of TKS, in order to reduce root damaging. Further development of adapted cleaning units on the harvesters to reduce tare, cultivation on ridges or raised beds, and breeding towards large tap roots could facilitate an efficient harvest. The Drive4EU consortium made the step from field trials at small scale (100 – 200 m²) to large scale (2 ha). Further yield enhancement is expected through improvement at the level of field germination and harvesting. This can be achieved by agronomic innovations but also at the breeding level such as working on root morphology to enhance the harvest efficiency.
4. Results on ecological analysis of the gene flow between TKS and wild dandelions
Summary analysis gene flow
Crossing experiments between Taraxacum koksaghyz (TKS) and related dandelion species indicate that hybridization is possible. This may result in interspecific gene flow in regions where TKS is cultivated and in SE Kazakhstan where TKS is growing in the wild. Both situations were investigated in this report. To determine whether 66 years after the end of seed production of TKS in the Swedish county of Skåne still traces of TKS were present in the environment, a detailed large scale population genetic study was carried out. At different distances to two fields where between 1947 and 1950 tens of millions of TKS seeds were produced, in total 576 wild common dandelions (Taraxacum officinale, TO) in 21 populations were sampled. These plants were genotyped for 10 codominant TKS- or TO-specific KASP DNA markers. In total 14652 alleles were typed. Not a single TKS-specific allele was found. This is consistent with the absence of TKS-specific morphological characteristics at the sampled locations. Although this negative result in the sample set cannot exclude the possibility of hybridization and introgression absolutely, it is clear that the impact of TKS seed production after almost 70 years in Skåne has to be very low. This result may be extrapolated to regions where no sexual diploid Taraxacum species occur, which is in western Europe north of 52 degrees latitude. In its native range in SE Kazakhstan TKS is spatially isolated from related dandelion species by habitat differentiation. However, at disturbed sites TKS may grow intermingled with other dandelion species. Two of such disturbed locations were investigated. From the combined analysis of ploidy level, reproduction mode and multilocus KASP genotypes, we infer that there is no indication for gene flow between TKS and sympatric Taraxacum species in natural populations in SE. Kazakhstan. TKS populations in SE. Kazakhstan are therefore not likely to be threatened by gene swamping caused by other dandelion species.
Artificial pollinations have shown that interspecific crosses between Taraxacum koksaghyz (TKS) and other dandelion species are possible, despite considerable differences in genome size. Koroleva (1939) successfully crossed TKS with other sexual diploid dandelions. TKS can also be crossed with sexual diploid common dandelion, Taraxacum officinale (TO) (P. van Dijk, personal observations) and with apomictic polyploid dandelions, for example triploid Taraxacum brevicorniculatum (TBR)(J. Kirschner personal communication). Małecka (1971) found natural hybrids between Taraxacum koksaghyz and T. officinale in the botanical garden of Jena, where both parental species were growing next to each other. This suggest that at places where TKS grows naturally or is cultivated in the vicinity of wild related dandelions, interspecific gene flow between dandelion taxa is possible. Whether this leads to introgression of TKS genes into the gene pool of wild dandelions and visa versa depends on the breeding systems, ecological differentiation and on many population genetic parameters, e.g. selection, genetic drift and assortative mating. While introgression is hard to predict, it may be measured by genetic marker analyses. In DRIVE4EU two of such sympatric situations were studied that are relevant with respect to gene flow between TKS and wild relatives: 1. two sites in southern Sweden where TKS seeds were produced almost 70 years ago; and 2. Two disturbed sites in south Kazakhstan within the native range of TKS, where TKS is growing in the wild intermingled with related dandelion species.
Discussion and conclusions gene flow
The situation in Skåne offers a unique opportunity to investigate the long-term impact of the cultivation of TKS on the gene pool of local wild dandelion populations. The seed production of TKS between 1947 and 1950 is documented in Joseffson (1953). Based on these data it can be anticipated that 10’s of millions of TKS seeds have been dispersed into the environment. The locations of the former seed production field were found back in May 2016 and populations of wild dandelions were sampled according to a scheme taking the high dispersal capacity of dandelion seed into account.
No wild growing TKS plants or dandelion plants with partial TKS morphology were found in the vicinity of the former seed production fields. The dispersal of seeds in the environment has definitively not led to large scale establishment of TKS populations 70 years after the seed production was abandoned. This may be due to the fact that TKS is not a very competitive plant species, as is clear by the fact that cultivation suffers a lot from competition by weeds.
TKS and native triploid apomicts may also have hybridized thus generating new polyploid apomictic clones. Backcrossing of these clones to sexual TKS could generate new apomictic clones with a greater TKS genetic background. Therefore the gene pools of wild dandelion populations were investigated with codominant species-specific DNA markers. Native dandelions that were collected are likely all to be triploid, perhaps some are tetraploid. If we exclude the atypical Contig2608-372 marker, a total of 4884 KASP assays have been successfully run (Table 5), each genotyping a single locus. Assuming that the native dandelions are triploid, this is equivalent to 14652 alleles. Among this number not a single TKS specific allele could be detected. Restricting this analysis to the populations within 2.5 km distance, it can be concluded that among 336 plants, or 9072 genes analyzed, not a single TKS-specific gene variant was found. This is consistent with the absence of TKS morphological characteristics at the sampled locations. Although this negative result in the sample set cannot exclude the possibility of hybridization and introgression absolutely, it is clear that the impact of TKS seed production after almost 70 years in Skåne was very low.
To what extent can these results be extrapolated to TKS cultivation for rubber? Wild dandelions in Skåne are triploid. Because these plants are obligate apomicts, they cannot be fertilized by pollen from TKS. Wild triploid apomicts produce only small amounts of viable pollen, because pollen meiosis is highly disturbed as a consequence of an uneven number of chromosome sets. The conditions at Skåne are thus unfavorable for hybridization and introgression. On the other hand flowering in rubber production fields will be much lower than in seed production fields. Since flowering may reduce rubber production flowering in rubber production fields flowering of TKS will be reduced as much as possible (e.g. by using vernalization dependent varieties and well-timed harvesting). In Europe, north of 52 degrees latitude sexual diploid dandelions are extremely rare. South of 52 degrees latitude sexual diploid dandelions become more common. Here in principle bi-directional gene flow between TKS and wild dandelions is possible. When TKS is grown in these regions it may be necessary to investigate the regional geographic distribution of wild diploid sexuals and triploid apomicts if gene flow is a concern.
Introgression and conservation of wild TKS in Kazakhstan
This part of the study was carried out to obtain a better understanding of the conservation status of TKS in its native range. Normally TKS is restricted to particular habitats and this ecological isolation will also result in spatial isolation. However, at disturbed sites this ecological isolation may breakdown, in the worst case resulting into genetic swamping by hybridization and the disappearance of TKS. At two such uncommon sites we investigated if TKS plants were fixed for TKS specific alleles or whether they contained alien alleles. This turned out not to be the case; even the putative morphological hybrid did not show signs of introgression. It can be concluded that in addition to ecological differentiation other gene flow barriers restrict the introgression of non-TKS genetic material.
This large scale detailed study could not find any traces of TKS in southern Sweden, 66 years after the cultivation for seed production was abandoned. This concerns both the establishment of pure TKS in the wild as well as the introgression of TKS genes in the local wild dandelions. Although this negative result cannot exclude the possibility of gene flow completely it is safe to conclude that the impact of TKS was very low. These results can be extrapolated to future cultivation of TKS in regions where local dandelions are triploid obligate apomicts, but not for regions where diploid sexuals occur. In Europe, north of 52 degrees latitude sexual diploids are extremely rare. South of 52 degrees latitude it may be necessary to investigate the local geographic distribution of diploid sexuals and triploid apomicts if gene flow is a concern. From the combined analysis of ploidy level, reproduction mode and multilocus KASP genotypes, we infer that there is no indication for gene flow between TKS and sympatric Taraxacum species in natural populations in SE. Kazakhstan. TKS populations in SE. Kazakhstan are therefore not likely to be threatened by gene swamping caused by other dandelion species.
Measurements that can be used for conservation of TKS
Taraxacum koksaghyz (TKS) represents an economic plant, an alternative rubber producer, with a potential of world importance. Because it is confined to a small geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future, a conservation is needed. TKS is restricted to an area in valleys of Kegen River, Saryzhaz River, Tekes River and Tuzkol Lake. As regards its habitats, TKS avoids sandy or marshy habitats in the valleys. It is an ecotonal plant thriving between the marshes and dry elevations, mostly associated with loose stands of Achnatherum splendens ("chia") or with meadows near springs dominated by Juncus salsuginosus or J. gerardii. TKS is a sexually reproducing diploid with sporophytic incompatibility and, therefore, obligate outcrossing requiring cross-pollination. Each of its large populations comprises the absolute majority of species' genetic variation. TKS currently exists at more than 30 localities, with only three macrolocalities really rich in TKS plants (Kegen, Saryzhaz and Tuzkol Lake). The condition of the localities is relatively satisfactory, and no emergency measures are needed. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit, after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to the soil degradation and erosion. As regards the expected trends in future, they include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. Also the continuing climatic change might reach a critical limit in this area in future. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing. The conservation plan should be launched at national and regional government levels, and all the local stakeholders should be involved or at least contacted. Continuing research based on the monitoring of water, climate and TKS population dynamics is an integral part of the conservation plan.
Conclusions measurements that can be used for conservation of TKS
1. TKS represents an economic plant with a potential of world importance. Because it is confined to a small
geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future, a conservation is needed.
2. TKS is restricted to a small area in valleys of Kegen River, Saryzhaz River, Tekes River and Tuzkol Lake. Its
occurrence in Xinjiang, China, was documented but not recently, and was confined to the border region. The
occurrence in Kyrgyzstan remains without proof.
3. In terms of ecology, TKS avoids sandy or marshy habitats in the valleys. It is an ecotonal plant thriving between the marshes and dry elevations, mostly associated with loose stands of Achnatherum splendens ("chia") or with meadows near springs dominated by Juncus salsuginosus or J. gerardii.
4. In terms of species biology, TKS is a sexually reproducing diploid with sporophytic incompatibility and, therefore, obligate outcrossing. Its population genetic variation is harboured within populations, so that each large population bears the absolute majority of species' variation.
5. TKS currently exists at more than 30 localities, with three macrolocalities really rich in TKS plants: the Kegen locality, the Saryzhaz locality and the Tuzkol Lake locality. The condition of the localities is relatively satisfactory, and no emergency measures are needed.
6. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit, after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to the soil degradation and erosion (including salt flat formation).
7. As regards the expected trends in future, they include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. Also the continuing climatic change might reach a critical limit in this area in future.
8. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing. The conservation plan should be launched at national and regional government levels, and all the local stakeholders should be involved or at least contacted. Continuing research based on the monitoring of water, climate and TKS population dynamics is an integral part of the conservation plan.
5. Results on scaled-up and optimised extraction and refinery protocol for TKS NR and inulin
Design of a biorefinery process
Summary
Several trials with the goal to design a bio-refinery process to obtain Dandelion Rubber from Dandelion roots were performed. Up-scalable equipment (hammer mill, bead mill and centrifuge) was used and materials were analysed for their properties.
Before milling (hammer mill or bead mill), the roots were cleaned from sand. With a hammer mill, a root pulp was produced that could be pumped into a bead mill.
The bead mill reduces the size of the fibres, but keeps the size of the rubber particles intact or even enlarges them. After several passages, there were no fibres found and the rubber yield looked to be quite good.
Rubber particles could be separated from the brown liquid suspension resulting from the bead mill. It was possible to separate the suspension into a solid phase and a (rather) clear liquid phase with rubber particles using a centrifuge.The rubber fractions were analysed with TGA and GPC. In the current set-up, a bead mill process with 2 or 3 passages seem to lead to the best results, combining separation efficiency, rubber recovery, rubber purity and rubber molecular weight. The polymer (rubber) content as measured with TGA was 81-84% and the molecular weight was 600-700 kDa as measured with GPC.
The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.
Previously, a laboratory ball mill was used to obtain Dandelion Rubber from Dandelion roots. ±20 g dry roots were cooked and put in a laboratory ball mill with ±180 g water. The mixture was ball milled for 1 hour at high speed. Subsequently, the resulting mixture was sieved and the residue contained large rubber particles. The purity of the rubber had to be improved (less acetone-ethanol-extracts, less ash, etc.) to meet the requested requirements.
The laboratory process was scaled up using barrels with larger volumes. However, the barrels were rotating at low speed and the process took some days before rubber particles could be sieved off and purified further. This process also involved a lot of manual labour and wash water. The wash water, probably containing inulin and soluble sugars, was not used further.
For the DRIVE4EU project, the aim is to design an up-scalable process since several tons of wet biomass (roots and leaves) have to be processed. To do so, a process using up-scalable equipment (hammer mill, bead mill and centrifuge) was tested.
Before milling (hammer mill or bead mill), the roots had to be cleaned from sand. During the hammer mill trial at Netzsch Hanau in May 2015, it was decided that the roots will be milled/chopped into large pieces. The sand can be washed away and the large root pieces continue to the next step of the process (pre-milling with a hammer mill). This process was used with FBR equipment to prepare material for next trials (bead mill).
For this trial, dried dandelions were available, harvested by ILVO (DRIVE4EU-WP3 partner) in June 2015. The whole dandelion was harvested, containing leaves and roots. Although the plant was washed at ILVO, they still contained sand, especially in the root collar. The roots themselves are not very thick, but it looks like they contain more rubber than previously. A kettle with a sieve on the bottom was used to clean the roots. The material is stirred and sand can go through the mesh. Sand is removed while draining the water from the kettle. This process is repeated several times to clean the roots thoroughly. Due to the stirring, the roots are chopped a little bit. A centrifuge machine was used to remove excess water. In the centrifuge extra water was sprayed to remove the last sand.
Pre-milling is performed on a similar way as during the Netzsch Hanau trial on May 12 2015. A hammer mill (Pallmann PHM 4-2) is used to reduce the size of the roots. First, the roots were milled and passed through a 12 mm sieve with continuous running water. Dewatered pulp was milled a second time and passed through a 5 mm sieve, again with continuous running water.
In total 150 kg of root pulp (± 10% solids) was prepared from 15 kg of dried roots. A bead mill LME-4 from Netzsch was used. Several tests were performed. Several batches of test material have been tested for their separation efficiency.
A stirred tank was filled with water and the bead mill is started. The slurry with root material was slowly added and pumped through the mill. The ground material (suspension) was circulated back into the tank (circulation) or into another tank (passage). When the suspension is poured over a sieve, the residue contains rubber particles. The rubber material has to be separated from the solids (fibre material). In the suspension, the rubber particles are visible because they are floating on the surface of the liquid. A disc centrifuge is used to separate the rubber from the other solids. This method uses a separation based on density. Spin tests showed that there is a clear separation between the water and solids phase. Rubber particles are floating on top of the water phase. The disc centrifuge can be continuously fed, the solids are collected (dark brown material) and rather clear liquid is continuously coming out.
In November 2015, a centrifuge and decanter trial was performed at GEA in Oelde. Suspensions from the bead mill trial in Selb were used. In a first test, a vibrating screen was used to separate large rubber particles.
Secondly, a centrifuge was used to separate solids (mud) from liquid with small rubber particles. The liquid was poured over the vibrating screen to collect these rubber particles. And during a last test, a suspension was processed through a decanter and solids (mud), liquid and rubber particles were collected.
Conclusions
A biorefinery process was tested in several steps to obtain Dandelion Rubber from dandelion roots.
- (Almost) all sand could be removed prior to milling.
- The slurry prepared with a hammer mill could be pumped through the bead mill.
- Rubber could be separated from the suspension by sieving, centrifugation and flotation.
- Centrifugation tests showed that rubber could be separated from the suspension with the water.
- In the current set-up, 2 or 3 passages through the bead mill seem to lead to the best results, combining separation efficiency, rubber recovery, rubber purity and rubber molecular weight.
o The polymer (rubber) content as measured with TGA was 81-84% .
o The molecular weight was 600-700 kDa as measured with GPC.
The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.
Pilot scale demonstration equipment
Several trials with the goal to design a bio-refinery process to obtain Dandelion Rubber from Dandelion roots were performed. Up-scalable equipment (hammer mill, bead mill and centrifuge) was used and materials were analysed for their properties. The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.In the period M24-M36, trials were performed at the location of Netzsch in Selb. For these trials, machinery from Wageningen FBR, Netzsch (Hanau) and GEA (Oelde) was transported to Selb to be able to perform the process semi-continuously at one site.
With the line-up of all this equipment, the partners were able to demonstrate a pilot scale process with pilot scale demonstration equipment.
Previously, a laboratory ball mill was used to obtain Dandelion Rubber from Dandelion roots. ±20 g dry roots were cooked and put in a laboratory ball mill with ±180 g water. The mixture was ball milled for 1 hour at high speed. Subsequently, the resulting mixture was sieved and the residue contained large rubber particles.
The laboratory process was scaled up using barrels with larger volumes. However, the barrels were rotating at low speed and the process took some days before rubber particles could be sieved off and purified further. This process also involved a lot of manual labour and wash water. The wash water, probably containing inulin and soluble sugars, was not used further.
For the DRIVE4EU project, the aim is to design an up-scalable process since several tons of wet biomass (roots and leaves) have to be processed. To do so, up-scalable equipment (hammer mill, bead mill and centrifuge) was tested to perform the process semi-continuously at one site.
Conclusions pilot scale demonstration equipment
A biorefinery process was tested with pilot scale equipment to obtain Dandelion Rubber from dandelion roots.
• Cleaning: kettle with stirrer and sieve combined with vibrating screen
• Pre-milling: Netzsch hammer mill CHM 23/20
• Bead-milling: Netzsch bead mill LME-4
• Separation: GEA decanter with vibrating screen
The trials performed at one location resulted in a biorefinery process with a complete line-up of this upscalable equipment.
Composition of available TKS-lines and their suitability for a biorefinery process
Dandelion roots, harvested by partners in WP2 (Breeding and seed production) and WP3 (Agronomy, harvest and storage), were used by the partners in WP5 (Bio-refinery design) to extract rubber and inulin. The background of the different TKS lines used, agronomy, harvest methods, and storage time/method were evaluated for their influence on composition and bio-refinery suitability. During the trials, it became clear that all types of roots could be processed with efficient recovery of rubber and inulin. Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process. It was shown that the rubber recovery yield was so high that almost all rubber is recovered, independent of the quality of the roots. Also, high concentrated inulin/sugar syrups were obtained. Based on the lab tests performed at WUR, the three partners Netzsch, GEA (WSPC) and WUR developed successfully a refinery process. This process is patent pending. The process was tested and proven with different and difficult raw materials. When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Inulin increases the viscosity too much, so bead milling and separation will become inefficient. In this way, also inulin recovery is improved. Most important is the removal of sand. Sand causes a lot of abrasion in pumps, mills and machines in general, decreasing the efficiency. Sand can attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material.
Dandelion roots, harvested by partners in WP2 (Breeding and seed production) and WP3 (Agronomy, harvest and storage), were used by the partners in WP5 (Bio-refinery design) to extract rubber and inulin.
The roots were different in several aspects:
- appearance (size, branching)
- ratio and amount of the components (inulin, rubber)
- production location and conditions
o in The Netherlands, Belgium or Kazakhstan
o on clay and sandy soils
o flat field or on ridges
- harvesting season (spring, autumn) and season (2014-2018)
- storage (dried, fresh)
The background of the different TKS lines used, agronomy, harvest methods, and storage time/method were evaluated for their influence on composition and bio-refinery suitability. The aim was to evaluate the background of the different TKS lines used, agronomy, harvest methods, and storage time/method for their influence on composition and bio-refinery suitability. The bio-refinery process basically consists of five steps: washing, pre-milling, bead-milling, separation and purification.
During the trials, it became clear that all types of roots could be processed with efficient recovery of rubber and inulin. Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process.
When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Inulin increases the viscosity too much, so bead milling and separation will become inefficient. Therefore a heating and separation step is used as part of the pre-milling step to remove soluble inulin. In this way, also inulin recovery is improved. Higher concentrated inulin/sugar syrups could be obtained (from less than 1° Brix, while at the last trials this concentration was improved up to 6°Brix even up to >13°Brix).
More important is the cleanliness of the roots. Too much weed can block the mills and screens. Fresh leaves also can block mills and screens, and it also prevents easy washing of the roots.
Most important is the removal of sand. Sand causes a lot of abrasion in mills and pumps, decreasing the efficiency. When sand stays too long in the process, it will attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material. Looking at the morphology of a dandelion root it can be seen that the leaves on top cover the root collar where a lot of sand is present. This sand is very difficult to wash away, especially with highly branched roots. Good results are achieved when the root collar is cut with e.g. a clog breaker. It is necessary to process the root collar because it contains a significant amount of rubber.
Conclusions Composition of available TKS-lines and their suitability for a biorefinery process
All types of roots could be processed with efficient recovery of rubber and inulin.
Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process. When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Too much weed can block the mills and screens. Fresh leaves also can block mills and screens, and it also prevents easy washing of the roots.
Most important is the removal of sand. Sand causes a lot of abrasion in mills, pumps and machines in general, decreasing the efficiency. Sand can attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material.
Based on the lab tests performed by WUR, the three partners Netzsch, GEA (WSPC) and WUR developed successfully a refinery process. This process is patent pending. The process was tested and proven with different and difficult raw materials. It was shown that the rubber recovery yield was finally so high that almost all rubber is recovered, independent of the quality of the roots. Also the inulin or sugar concentration in the separated liquid was improved within the project trials. At the beginning the sugar concentration was less than 1° Brix, while at the last trials this concentration was improved up to 6° Brix even up to >13°Brix.
Large scale samples of dry rubber and inulin (to be used in product development)
During a large scale pilot-trial in February 2018, large samples of dry rubber and inulin were produced to be used in WP6. In February 2018, GEA, Netzsch and WFBR have processed the larger amount of dandelion roots from the Rusthoeve harvest October 2017 to obtain rubber during a large trial at the facilities of GEA in Oelde. Afterwards, WFBR has washed the rubber samples with ethanol. Rubber samples were obtained with a combined weight of 2500 g. Purity of each sample differs slightly. The rubber is divided in three equal portions for Apollo, Mitas and Qew.
Also, large amounts of solubilized inulin were produced of which 50 liters was saved to model the inulin/fructose refinery process. In May and August 2018, an even larger trial was scheduled. The quantity of rubber material extracted was 20 kg.
6. Results on testing and application of TKS NR and inulin in end product uses
Bike and car tyres
In the period 2017 – 2018 three batches of Natural Rubber (NR) from Rubber dandelion have been received from WP5 for further evaluation and prototyping. The first batch was used by ATG for evaluation of in compound properties for bicycle tyres and also for making the first set of bicycle prototypes. The batches 2 and 3 were divided between the partners Apollo, QEW and Mitas and were used for the compound testing and prototyping of car tyres, rubber good and an off road tyre. In this deliverable report, the results for the bike and car tyres are presented.
The compound properties of the dandelion NR in a bicycle formulation were on an acceptable level. Also the prototype bicycle tyres were tested indoor and in a small field evaluation test. The performance of the prototype tyres with NR dandelion was at an acceptable level.
In 2018 the NR dandelion was used in a set of passenger car tyres, 195/65R15 Snowtrac 5. Compound properties were at a comparable level to Hevea natural rubber and also the tyre results indoor and outdoor (snow, wet) were comparable to the reference.
The objective was to create prototype products based upon the rubber extracted from Rubber dandelion (Taraxacum koksaghyz; TKS). Thereto, the basic polymeric properties and rubber material properties after cross-linking have to be assessed. The assessment of the rubber material properties will start with measurements of the purity and the molecular weight of TKS rubber as compared to Hevea and synthetic rubber. The impurities of Natural rubber of TKS will be further investigated on composition and quantity. In a second step, the vulcanization and compounding process of dandelion rubber will be addressed. The basic idea is to evaluate such rubber samples in a standard formulation (100 phr against NR) and in other couple of standard formulations in blends with styrene-butadiene rubber (SBR) and butadiene rubber (BR). The cured samples will be tested for cure kinetics and reversion resistance, hysteresis with a mechanical spectrometer and with a Goodrich flexometer and for several mechanical properties (hardness, Mooney viscosity, etc.) and temperature dependent behavior.
Commercially, compounding modifications are used to optimize the properties of Hevea rubber or synthetic rubbers. These modifications will be adapted to the properties of TKS rubber. This task could only be performed when there was enough material available.
Finally several prototype car tyres, made with the natural rubber from TKS, were produced and tested indoor and outdoor (snow, wet) and showed to be comparable to the reference.
The polymer received from WP5 has been tested on purity. Purity was always lower as compared to regular natural rubber.
Several analytical techniques have been used to find out the composition of these impurities.
• Extraction in THF, acetone and ETA
• Low heating of TGA combined with Pyrolysis GC-MS at TGA temperature with high mass loss
No other components are found as in regular NR only in higher quantities. A test with liquid isoprene (low molecular weight shows a TGA curve which is comparable to regular natural rubber; no extra weight loss in the temperature range 20-300oC. So it seems to be that the impurities as seen in TGA are not caused by low molecular weight NR.
In Natural dandelion the amount of impurities is higher as in natural rubber from Hevea brasiliensis. These higher content impurities might have effect on mixing of the compound. For this reason mixing experiments have been done to get indication of mixing behaviour of compounds with a high amount of Natural rubber. These mixing experiments were done on Brabender Plasticorder 50 and 350 cc. Before these experiments could be performed mixing cycles has to be developed for the se miniature mixers. The properties of the compound with Natural rubber from dandelion are reduced in comparison to the reference. This probably caused by the higher content of the impurities. These impurities will probably lead to lower shear forces and these low shear forces in the miniature mixers, lead to significant lower dispersion of carbon black in the polymer matrix
The results found with the 50 and 350 cc mixers were comparable.
Bicycle tyres
For the manufacturing of the PCR prototypes compound have to be mixed. Due to limited quantity of NR dandelion available the compounds were mixed at a pilot plant external Apollo. The reference was the shoulder tread compound for the Vredestein Fortezza (25phr NR). In the experimental variant all the NR was replaced by the NR dandelion.
The following observations could be made after testing:
• Equal tensile strength, elongation at break
• High hardness,
• Equal hysteresis (tan delta 70oC = indicator rolling resistance)
• Good dispersion
Prototype tyres have been produced for testing purposes and demonstration projects.
Test results
In an independent laboratory the tires have been test on wet grip and rolling resistance. The following results were found for Dandelion rubber tyres:
• RR better as reference 4-5%
• Wet grip better (+6%) to worse (-4%) dependent on the inflation pressure
Test were done by Tyres Laboratory Wheel Energy Oy (Finland)
Passenger car tyres
For the manufacturing of the PCR prototypes compound have to be mixed. Due to limited quantity of NR dandelion available the compounds were mixed at a pilot plant in Germany (20 liter intermeshing mixer). The reference was the winter tread compound for The winter H product line (13phr NR). In the experimental variant all the NR was replaced by the NR dandelion.
The results of the compound with NR dandelion were comparable to the reference.
195/65 R 15 91H SNOWTRAC 5 Tyres have been produced with the regular compound and a version with NR dandelion. During manufacturing no differences were observed between the prototypes with regular NR and NR dandelion.
The tyres (reference and NR dandelion version) were tested on indoor and outdoor. Indoor test were performed in the Apollo indoor test center, winter performance at SPHG New Zealand. The wet performance could not be tested within the time frame of the project and are not reported here.
Tyre results of both variants were comparable!
Conclusions
1. Natural rubber from dandelion has a lower purity as from Hevea brasiliensis
2. Compound properties of bicycle tyre formulation with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
3. Compound properties of passenger Car tyre tread formulation with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
4. Performance of bicycle tyre with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
5. Performance of passenger car tyres with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
Prototype rubber goods
The initial aim was to produce different General Rubber Goods (GRG) parts to evaluate a variety of mechanical properties:
- Abrasion resistance (Agri roller)
- Dynamic behavior (Bearing)
- Static behaviour (Grout seal)
The smallest real size sample is the Agri support roller. This is a patented hollow support roll which controls the seeding depth behind a tractor and reduces the impact on the soil. It requires flexibility, durability, ozone and UV resistance and some specific processing properties like tack, die swell and green strength for cutting.
The product is coreless molded from NR compound and has a closed hollow chamber inside. The rubber is injected with air during curing. The steel disk mounted inside the roller (as a rim) will make the roller airtight.
We have chosen this product due to the application (agricultural) and the easiness to convince the market to use TKS rubber for this application.
Starting point is to replace to surface of the roller with TKS rubber compound in which we’ve replaced 100% of the NR (not a blend) with TKS NR. The benchmark NR is a standard TSR 10 50-80 Moony grade from Vietnam.
The first step in production is the extrusion of the profile. Due to the fact that we did not have enough compound to fill the 120mm extruder, we’ve decided to use a smaller NR base and add an outer layer of TKS compound on top.
The extruded profile will be cut, heated and spliced without any solutions or tack agents. This critical step in the process is important as lack of initial tack will result in 100% rejected products. The molding is done in a special method (IP) and cannot be disclosed or described in this report.
After curing the roller is tested in a specially designed test rig to measure:
- Wear resistance
- Flexibility
- Degradation (under pressure and temperature)
The roll will be mounted to run against an abrasive resin coating. The roller will be measured under different loads, speed, temperatures and angles to simulate all extremes that could occur in the field. These are long test cycles to simulate years of operation in the field. The effect under extreme conditions can be evaluated by visual inspection as the surface of the roller clearly shows the degradation of natural rubber. The samples made from TKS rubber have been produced in August 2018 and the tests are ongoing. The comparison will be made against similar products made in the same mold/cavity and on the same press.
We expect the first results in November 2018. The report will be a comparison table on the compound, the processing properties and the mechanical properties of the final product.
7. Results on demonstration of the economic viability of the TKS production chain for NR and inulin
Economic analysis of rubber and inulin from TKS
The aim of this economic analysis is three folded, following three approaches and assessment are included:
- revenue based modelling,
- business-economic assessment, and
- socio-economic assessment.
-
Revenue based modelling
Revenue based modelling is a general economic analysis of natural rubber and PEF (Polyethylene
furanoate) from Rubber dandelion following the methodology presented in deliverable 7.1 as well.
With this assessment putative framework conditions for the future realization of this new
valorization chain of these two products from Rubber dandelion are pinpointed. The analysis is
mainly based on data and results gained in the DRIVE4EU project, EU-PEARLS, literature and general
information, which were used to calculate some general economic indicators.
Business-economics
Business-economics includes cost calculation of production of Rubber dandelion and by-products in
the DRIVE4EU system. DRIVE4EU system includes 4 process steps (cultivation & harvest, transport,
rubber biorefinery and PEF biorefinery) and technical and economic input data has been provided by
project partners or literature review. Results are given as yearly costs or specific costs related to total
amount of products (rubber and PEF). Cost calculation allows identifying the main impact factors on the production costs. Based on the identification of main impact factors changes to be expected in
the future (targets for e.g. yield, rubber content, decrease in cultivation work) are used for sensitivity
analysis. Results of sensitivity analysis are interpreted to make suggestions for improvements in the
DRIVE4EU system. Based on prices for reference (conventional) products and the production data of dandelion rubber and PEF revenues are calculated to show the economic competitiveness of the DRIVE4EU products now and in the future.
Socio-economics
The socio-economic assessment serves to analyse potential impacts of newly introduced, EU-located
Rubber dandelion production chains on the EU economy. The analysis focuses on the potential value
added generated by these production chains in different economic sectors in the EU as well as
abroad. Major questions are thus, which magnitude of value added could be achieved, which share
of this value added remains in the EU and on which sectors of the economy it may have the most
important impact. In order to address the competitiveness with alternative crops, a brief comparison
with the value generation of conventional crops is undertaken.
The key findings of the general economic analysis for the Rubber dandelion value chain to produce
natural rubber and PEF are:
- Currently there is little reliable information available for the future commercial production of
natural rubber and PEF from Rubber dandelion.
- There are no estimations available for the main cost components along the processes of the
whole value chain available. With the calculation tool for the general economic analysis, using
the assumption, the total production costs for natural rubber and PEF are assumed to be lower
than the total revenues from these products.
- The general economic analysis was based on the following aspects
o Consideration of two possible future business cases in “10 years” and “25 years” with
▪ Rubber dandelion yield 40 – 60 t/(ha*a)
▪ natural rubber yield 0.9 – 2.0 t/(ha*a) and
▪ PEF yield 1.8 – 4.9 t/(ha*a).
o The whole value chain from Rubber dandelion cultivation to natural rubber and PEF
under consideration of the valorization of process residues for animal feed includes
the following 7 main processes:
▪ Rubber dandelion cultivation and harvest
▪ Rubber dandelion transport
▪ Rubber dandelion (drying &) storage
▪ Biorefinery (including processing of inulin to PEF)
▪ Feed production from roots, leaves and pulp
o A “Cost calculation tool” is developed to estimate possible cost distribution along the
whole value chain for Rubber dandelion. The starting point of this cost calculation is
the estimation of the possible revenues on the market of natural rubber, PEF and
animal feed from Rubber dandelion biorefining.
o The main inputs in the tool are: technical data, revenue data from the market,
characteristics of the cases, assumptions and estimations.
Main changes to DRIVE4EU today are:
- Annual costs:
Total costs decrease from 5,752 to 909 Mio. €/a. Costs for cultivation & harvest decrease
significantly due to the future changes/assumptions and this effects significantly on the total
costs. Percentage of cultivation and harvest decreases from 94 % to 64 %.
- Specific costs:
Also specific costs are lowered from range 14 to 22 to range 2.2 – 3.3 €/t tot prod. For the
specific costs the yield of fresh roots and the rubber content are the major influences that
results in this particularly high cost reduction (about 85 %).
- Cultivation & harvest:
Main cost factors are agricultural land rent and agricultural machinery rent (together 72 %).
Plant protective agent holds a percentage of 11 %.
- Rubber Biorefinery:
The energy costs (heat and electricity show together 51 %) have the major influence. Then
followed by the investment costs (annuity and insurance&maintenance show together 48 %).
- PEF Biorefinery:
The investment costs (annuity and insurance&maintenance show together 41 %) have the
major influence. Then followed by energy costs for heat with about 37 %.
Conclusions
Following conclusions can be drawn from the results of cost calculation of DRIVE4EU system:
- DRIVE4EU system today is not economically viable because of
o especially high costs in process step cultivation and harvest,
o low yield of fresh roots and
o low rubber content of the roots.
- Costs of cultivation and harvest are mainly determined by
o costs for agricultural land and
o costs for agricultural machinery
o followed by costs for plant protective agents.
- Further developments in the process step cultivation and harvest are necessary:
o increasing the yield of fresh roots (today 6.6 t/ha; Future1: 40 t/ha; Future2: 59 t/ha)
and
o increasing the rubber content of the roots (from 10 % up to 15 % on DM).
o reduction of costs for agricultural land, agricultural machinery and plant protective agent.
- Main percentage of cost in Rubber biorefinery:
o energy (electricity 31 %, heat from gas 24 %; together 55 %)
o investment costs (annuity 30 %, insurance and maintenance 14 %; together 44 %).
- Main percentage of cost in PEF biorefinery:
o energy (heat from gas 38 %)
o investment costs (annuity 26 %, insurance and maintenance 13 %, together 39 %)
o auxiliary materials (sulfuric acid 1 %, methanol 1 %, ethylene glycol 17 %, acetic acid
1 %; together 20 %).
- Further developments in the process step Rubber and PEF biorefinery are necessary:
o improvement of production efficiency to reduce the costs for energy and auxiliary
materials
o reduction of investment costs
- The analysis of future improvements showed, that dandelion rubber and PEF from DRIVE4EU
system can become economical competitive if the assumed changes/improvements, e.g.
higher yield, higher rubber content, lower fertilizer demand, lower electricity demand, will
actually occur in the future (10 to 25 years).
Socio-economics analysis
The socio-economic assessment serves to analyse potential impacts of newly introduced, EU-located
dandelion production chains on the EU economy. For the production of natural rubber from Rubber
dandelion, this would result in a replacement of natural rubber imports from Asia. For the PEF part of
the production the replaced imports are less obvious as part of the PET production industry is already
located in the EU while a share of PET is imported. Thus, whether raw material (e.g. crude oil) or PET
imports are replaced depends on the specific case and/or on market dynamics. The analysis focuses
on the potential value added in Euros per year generated by these production chains in different
economic sectors in the EU as well as abroad. Major questions are: Which magnitude of value added
could be achieved? Which share of this value added remains in the EU? On which sectors of the
economy may it have the most important impact? In order to address the competitiveness with
alternative crops, a brief comparison with the value generation of conventional crops is undertaken.
The analysis suggests that, even in the 50-50 scenario, the agricultural sector would clearly benefit
most from the introduction of EU based dandelion value chains. This is primarily due to the fact that
the “auto supply” of the agricultural sector is higher than in the chemical industry; while approx. 48%
of inputs to the EU based agriculture stem from agriculture itself, in the chemical industry this share
is 32%. As stated above, standard splits (multipliers) between the input sectors where used. It is likely
that the high input from agriculture to the agricultural sectors is to some extent caused by the
production of feed for animal breeding which does not apply to our case. The use of standard
multipliers can thus only provide a rough idea on value added generation in the EU. A deeper analysis
including value chain data (a “vector”) specifically developed for dandelion products would help to
produce more reliable results. For this purpose, however, more data on the actual production chain
would be required which so far is not available.
The analysis suggests that the major share of the generated value added remains in the EU. With a
replacement of the total import of natural rubber, a value added in the EU agricultural sector of
about 1.2 billion or 1.6 billion EUR in the two scenarios respectively would be generated. Given that
the total value added in this sector in 2014 was 170,690 million EUR according to the WIOT
(exchange rate of 2014), this would correspond to 0.70% or 0.94% respectively of the sector’s value
added. The effects of a potential replacement of other agricultural crops would require a much
deeper analysis, involving agricultural and trade models. In the chemical industry the EU value added
would amount to 850 million or 540 million EUR (50-50; 70-30 split). Based on a total 2014 value
added of 130.168 million EUR, 0.65% or 0.41% of the sector’s value added could be generated. Also
here, potential replacement effects, e.g. due to capacity constraints in the biorefinery sectors, are
not considered. On the other hand, e.g. crop rotations potentially leading to additional proceeds,
were not considered. The generated values are thus to be seen as rough estimations. Provided that
the analysis focuses on two specific products only, the orders of magnitude can however be seen as a
fair share of the existing sectoral activities.
At least for rubber, the analysed value added generation can be assumed to be additional to, rather
than displacing, existing value added of the alternative supply chains. Rubber is currently fully
imported, mostly from Asia. For PEF, the situation differs as there is a significant oil refining industry
in Europe, partly covering current demand of PET. Therefore, a certain share of the value added from
the PEF value chain may not be additional to current European value added.
Survey of economic viability of rubber and inulin from TKS
The aim of this research was to provide information on reasons for favouring or disfavouring rubber and inulin from Rubber dandelion compared to conventional rubber and inulin.
A SWOT (strengths, weaknesses, opportunities, threats) analysis of the DRIVE4EU process is described. The whole project team provided therefore information on:
• Reasons for favouring rubber, inulin and fructose from Rubber dandelion – this is covered mainly by the collection of the strengths and
• Reasons for disfavouring rubber, inulin and fructose from Rubber dandelion – mainly covered with the collecting input of weaknesses
• Technical and non-technical barriers – covered mainly from the collection of threats, and
• Technical and non-technical boosters – covered mainly by the inputs for opportunities
Furthermore we described bottlenecks of the DRIVE4EU process during the project and after the project.
Technical minimum requirements/standards for rubber and inulin (for using it for specific products) are described here. This gives information on the usability of rubber and inulin from Rubber dandelion compared to conventional rubber and inulin. Another part of this deliverable deals with the integration in existing infrastructure.
The biggest strength of DRIVE4EU is the local production of natural rubber, which will be offered by the European production chain developed within the project. Another strength that should be considered is the production of an alternative source for natural rubber and furthermore as well the reduction of the dependency on natural rubber from South-East Asia. A good quality rubber with high molecular weight is expected, and the biorefining as a combination of existing processes is most important for the DRIVE4EU consortium, given that the partners have a wide experience and technology background knowledge in their special field. The upscaling of the processes seems to be simple and easy to handle.
The dandelion would be an annual crop, i.e. the crop will be annually harvesting, in comparison to the rubber tree for conventional natural rubber production, which need 7 years to harvest the first time natural rubber from the tree. A further strength is the availability of inulin in the root next to the natural rubber, so DRIVE4EU is developing a production chain for a bi-product crop for natural rubber and inulin.
Further strengths with votes are: new discoveries for science, cultivation in Europe demonstrated, further improvements possible e.g. rubber content, we have a promising process piloted, no allergic reaction by using natural rubber dandelion, dandelion can be processed for several products, good partners for the whole supply chain, less environmental impact expected, and research of very important alternative source of natural rubber (NR).
Conclusions survey of economic viability of rubber and inulin from TKS
A SWOT Analysis was performed to evaluate strengths, weaknesses, opportunities, threats of the DRIVE4EU process. In this deliverable the methodology of the SWOT analysis is presented, as well as the approach chosen in DRIVE4EU explained and the results of the SWOT analysis in DRIVE4EU. A summary provides information of the most important SWOTs ranked by all project partners.
Economic bottlenecks during the project phase were evaluated, further research and development is needed to reach marketable products, but within all process steps and so the whole value chain was successfully further developed. Needs for further developments are e.g. reach higher natural rubber yield per hectare, quality und purity of natural rubber from Rubber dandelion. Further prototypes from rubber dandelion, next to the high performance bicycle tyres, will be produced in the next months; therefore in relation to a successful production of prototypes more information can be prepared at the end of the project.
With further research and development in different parts of the DRIVE4EU value chain the costs can be lowered and the process can be more and more economic viable.
Market aspects, legislation and regulatory aspects concerning rubber and inulin from TKS
The economic analysis and the life cycle assessment (LCA) in work package 7 is a horizontal
activity of the project DRIVE4EU. On one hand the economic and environmental analyses and assessment should assist the other WPs in the development of most attractive technical solutions and to set up possible integrated valorization chains from TKS cultivation to the final product portfolio made from TKS, e.g. rubber, inulin, chemicals, energy carrier. On the other hand the economic and environmental analyses should set the framework of conditions under which a future commercial cultivation and use of TKS might be possible and the assessment should identify the key factors to be successful on the market in future.
The aim was to provide information on the market of rubber and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET; as a product based on inulin) based on world, European and Kazakh data. Information on production volumes, main producing countries, EU imports, EU exports, prices is summarized. Furthermore this analysis provides information on the regulatory aspects and information on legislation and subsidies.
In this part information on the market of natural rubber (NR) and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET) based on world, European and Kazakh data is provided. Market aspects like production volumes, main producing countries, EU imports, EU exports in relation to natural rubber, tyres, general rubber goods, inulin and PET are summarized.
The world natural rubber market rises to a total of 12.6 million tons in 2016. The six largest producing countries of natural rubber were Thailand, Indonesia, Vietnam, China, India and Malaysia. Not all of these countries are net exporters of NR, e.g. China and India are net importers of NR.
Currently natural rubber is not produced in Europe. Therefore the EU is totally dependent on imports from the natural rubber production countries. In 2016 the EU imported about 1.2 million tons of natural rubber. 34% of this amount came from Indonesia, 18% originated from Thailand and further 16% came from Cote d’Ivoire. The consumption of natural rubber in the EU is mainly driven by the tyre industry which amounts to 76% of the total demand in 2016. The residual 24% in 2016 belong to the general rubber goods (GRG) sector. Tyres market grew in the last five years (2011 – 2016) at a rate of 2.5% per year and is predict to grow further 2.9% per year between 2016 and 2021. GRG consumption will also grow 2.9% per year until 2021.
Due to the fact that Rubber dandelion is a non-food crop, it is maybe not possible to use the inulin from the Rubber root to use inulin for nutrition purposes. Another aspect is the small market volume of the inulin market. Bringing huge amounts of inulin into the market would affect the inulin market
significantly. For this reasons the PET market could be more relevant for Rubber dandelion, using the inulin as a resource to produce PEF (Polyethylene furanoate) as a substitute for PET.
Conclusions market aspects, legislation and regulatory aspects concerning rubber and inulin from TKS
In this research part information on the market of natural rubber (NR) and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET) based on world, European and Kazakh data was provided. Market aspects like production volumes, main producing countries, EU
imports, EU exports in relation to natural rubber, tyres, general rubber goods, inulin and PET are summarized.
The world natural rubber market rises to a total of 12.6 million tons in 2016. The six largest producing countries of natural rubber were Thailand, Indonesia, Vietnam, China, India and Malaysia. Not all of these countries are net exporters of NR, e.g. China and India are net importers of NR.
Currently natural rubber is not produced in Europe. Therefore the EU is totally dependent on imports from the natural rubber production countries. In 2016 the EU imported about 1.2 million tons of natural rubber. 34% of this amount came from Indonesia, 18% originated from Thailand and further
16% came from Cote d’Ivoire. The consumption of natural rubber in the EU is mainly driven by the tyre industry which amounts to 76% of the total demand in 2016. The residual 24% in 2016 belong to the general rubber goods (GRG) sector. Tyres market grew in the last five years (2011 – 2016) at a rate of 2.5% per year and is predict to grow further 2.9% per year between 2016 and 2021. GRG consumption will also grow 2.9% per year until 2021.
Due to the fact that Rubber dandelion is a non-food crop, it is maybe not possible to use the inulin from the Rubber root to use inulin for nutrition purposes. Another aspect is the small market volume of the inulin market. Bringing huge amounts of inulin into the market would affect the inulin market significantly. For this reasons the PET market could be more relevant for Rubber dandelion, using the inulin as a resource to produce PEF (Polyethylene furanoate) as a substitute for PET.
The global PET production in 2014 amounted to some 41.6 million tons, and it is forecasted that by 2020 its production will be approximately 73.4 million tons. With more than 35% in 2015 beverages hold the highest market share of PET. In 2016, some 485 billion PET bottles were produced worldwide, and it is forecasted that in 2021, some 583.3 billion of these plastic bottles will be produced. The total European plastics converter (EU28+NO/CH) demand of PET lies at approx. 3.6 million tons in 2016. PET price of bottle grade fee delivered PET lies at around €1,115/tonne FD (free delivered) in Europe at the end of August 2017 which was then exceeded in September 2017 to reach €1,130/tonne FD Europe.
Over all the process steps in the DRIVE4EU value chain and for the products different regulations or legislative issues (e.g. Nagoya Protocol, Plant variety property rights, REACH) has to be considered and clarified before a commercialisation.
Working in the field of alternative NR sources, DRIVE4EU contributes to the sustainability of NR. Furthermore DRIVE4EU offers the possibility to become less dependent on the imports of NR.
Environmental aspects of rubber and inulin from TKS
The environmental assessment was performed to identify, quantify and assess the most important environmental impacts and benefits of the production of rubber and PEF from inulin from Rubber dandelion, based on LCA. The environmental effects are analyzed for each process in the value chain (cultivation, transport, and conversion) and in comparison to the processes of conventional natural rubber from rubber trees and PET based on fossil resources.
The approach chosen included the following steps:
- Collection and assessment of information on the various technical systems and production processes of natural rubber and PEF/PET from Rubber dandelion and from conventional sources - from raw material extraction and cultivation to final products
- Definition and description of LCA system boundaries and elements of DRIVE4EU system and reference systems
- Performing LCA for complete DRIVE4EU value chain
- Assessment of the possible range of the most important environmental effects from rubber and PEF from inulin from the DRIVE4EU system as well as from conventional production
- Drawing of the main conclusions and identification of further R&D issues
The objective of this Environmental impact analysis was to identify, quantify and assess the most important environmental impacts and benefits of natural rubber and PEF production from Rubber dandelion (Taraxacum koksaghyz, TKS), based on life cycle analysis. The environmental effects were reported for each step in the value chain (cultivation and harvest, transport, biorefinery – divided in Rubber refinery and PEF refinery) and in comparison to the processes of conventional natural rubber and PET production.
The assessment of the DRIVE4EU system includes the comparison to a reference system with the substituted conventional products. The reference system provides the same services and products as the DRIVE4EU system with conventional products. All process steps of the value chain are included
for the reference system and for the DRIVE4EU system. For natural rubber of Hevea tree an LCA was performed to analyses the environmental impacts of natural rubber from Hevea tree based on literature data.
In the environmental assessment 24 concepts are included. Eight cultivation concepts varying following characteristics can be chosen: country (Belgium and The Netherlands or KZ Kazakhstan), planting method (sowing or planting), density of plants (low or high), and irrigation (yes or no). For the
processing of the Rubber dandelion roots in biorefineries three possible first commercial concepts are considered defined by the rubber production capacity of 5,000 t per year, 12,000 t per year, or 120,000 t per year.
The LCA of the DRIVE4EU system shows that due to the current state of technology the environmental effects of the DRIVE4EU system are higher than for the conventional reference system. The main influencing factors of the environmental effects are the cultivation and harvest process step especially fertilizer, plant protective agents and diesel. The share of cultivation and harvest lies between 75% and 90% (concepts with planting show higher GHG emissions than concepts with sowing) of the total GHG emission. Comparing to natural rubber from Hevea tree the cultivation and harvest of Rubber dandelion is completely different; the aim in DRIVE4EU is to have as much mechanical work as possible, harvesting latex from Hevea trees results in a lot of manual work.
A sensitivity analysis based on integration of LUC, different energy sources and for future improvements was undertaken. LUC has a significant effect on the greenhouse gas emissions and higher the GHG emissions significantly. Including LUC the cultivation and harvest process step shows
a share of more than 90% of the total GHG emissions. The GHG emissions of the base concept B&NL, sowing, high, y, 120kt without LUC can be reduced by applying renewable energy resources by 19%. In the future 1 the GHG emissions can be reduced by 57%, and in the future 2 by 65%.
The analysis of future improvements showed, that the environmental effects of the DRIVE4EU system could be reduced with possible future improvements. Results of “acidification” and “ozone creation” of the future 2 improvements are in the same range as the results of the conventional
reference system. Following future improvements are assumed, e.g. higher yield, higher rubber content, less fertilizer and plant protective use, lower energy demand in refinery.
Potential Impact:
Potential Impact
One goal of the project was to link key stakeholders in the production chain processes with project news and results. As a second effect, disseminating DRIVE4EU’s goals, intermediate and final results was also an important way to attract partners in EU and worldwide. The dissemination of the project results was essential in general to ensure the international visibility of the project. The concrete actions to achieve the highest degree of dissemination and exploitation of the DRIVE4EU results were the following:
✓ Setting up a website which made sure that users return to the website at regular intervals combined with the development of promotional materials (leaflets, press releases, special reports) which were spread through Europe and which invited interesting partners to contact the consortium or visit the website. The website incorporated a “public”, and an “internal” area where partners were able to share documents etc.
✓ Presentations of the project’s objectives and results during events, forums and conferences. DRIVE4EU was a demonstration project, and therefore all partners tried to present their results at conferences held outside of the project.
✓ Publication of project results in scientific journals, industry oriented journals but also in consumer focused magazines with a large distribution where information about the DRIVE4EU results reached the general public.
✓ Participation and organization of workshops on selected topics bringing together a scientific audience (along with the industry representatives) discussing about the outcomes of the project and future directions of the research activities.
✓ Production and distribution of promotional material of the project’s results, progress and potential benefits - e.g. leaflet, articles, press releases etc., but also the production of promoting materials like rubbers with a printed DRIVE4EU logo or a demonstration box including dissemination material.
✓ Scientific publications and presentations in international workshops and conferences that diffused the R&D results to stakeholders and companies. This included also articles in special magazines (e.g. magazines for the farming industry and tyre fabricants).
More detailed information on the communication and dissemination activities can be found in DRIVE4EU deliverable D8.3 Continuous dissemination and exploitation.
In order to ensure the application of a successful dissemination that diffused information but also contributed to the recognition of the project’s website and other project deliverables, at the project start, a strategy for the implementation of dissemination actions has been prepared and the main dissemination means were defined. The main 3 dissemination lines were:
1. Electronic/Digital dissemination tools: Project website, e-newsletter, e-publications, e-press releases, etc.
2. Hard copy dissemination tools: Project leaflet and posters
3. Individual dissemination tools: Project presentations, oral dissemination at conferences and workshops etc., networking with related projects and platforms, combined course with lectures and field training, etc.
Dissemination materials and activities:
• Logo
An important action in order to establish the project’s identity and to support “brand recognition” was to design a project logo, which is associated and included in all documentation (paper or electronic) and publicity material relating to the project. The identity of the project is guaranteed by the project logo.
• Website
The project website was an important and versatile dissemination tool. The website was continuously developed for disseminating project results, for providing information related to the project and the partners and for the communication among all interested parties. It should be noted that the website served as an interaction point among parties interested in project results and also as the basic point for providing DRIVE4EU related information to all external parties. Indeed, the project web-communication platform was a constant node aiming not only to present and disseminate the project’s results but also to be a referenced site containing useful disseminating material, as well as useful links related to the field of the project. The website was a dynamic tool with ongoing updates and changes over time. The purpose of the project website was to provide access to project results at two levels: one public and one private (i.e. password – protected) for project partners (Member Area) respectively. The website’s address is the following: www.drive4eu.eu.
The website will be available approx. one year after the project ends. Documents for downloads and project relevant events can be added on purpose.
• Articles and press releases
Press releases for the project were created by the project partners in order to present the project goals to a larger audience through magazines or e-press. These press releases raised public awareness about the project and the project objectives. Through these press releases information were diffused and thoughts were exchanged regarding the DRIVE4EU project to groups of stakeholders, commercial and industrial players strongly related to the rubber sector but contributed to the reputation building of the project team.
There has been a long list of scientific publications, articles, interviews, presentation and conference visits from all project partners. More information can be found in the tables “list of scientific publications” and “list of dissemination activities”.
• Brochures
A project brochure was produced in English, electronically and in hard copy. It was used to communicate the existence of the project, its partners, aims, objectives, contents and goals. A short project description was prepared for dissemination among stakeholders, such as breeders, processing industry, extraction machinery producers, biorefinery industry, rubber and chemical industry, at conferences and for other interested actors.
A second electronical brochure depicting the final results and outcomes of the project was developed and will be provided online at the project website for downloading. A draft version is available; the final version will be presented at the final stakeholder workshop.
• Newsletter
Newsletters in English were produced providing information on the project development and events. Newsletters were developed and disseminated during the project duration and sent via email to registered users of the website and further contacts. The first issue of the DRIVE4EU newsletter introduced the project, the project’s objectives, the consortium partners, providing contact points to obtain further information. The other newsletters were used to provide updates on project progress, the project’s results, support the project activities and achievements, and encourage participation in forthcoming initiatives and events. These newsletters were electronically distributed and made available on the project website. A last newsletter will be provided online with the final results, this will be made available in October 2018.
• Further dissemination means
Rubbers with printed DRIVE4EU logo as dissemination material were made and provided to all project partners. The rubbers served as promotion material and were spread to stakeholders in different conferences, workshops and events by the project partners.
A “demobox” with jars and information material was developed. With this demobox the whole value chain of DRIVE4EU is visualized. Information about the complete chain from seed to product is presented and can be explained to the broader public easily. Each partner received 2 demoboxes for demonstration purpose. Jars included with samples for:
o Seeds
o Root
o Biorefinery
o Rubber
o Inulin
o Rubber product
o PEF/PET product
A YouTube movie giving information about DRIVE4EU has been produced by DLO-PRI and was put on the DRIVE4EU website at the 1st page as well.
• Workshops, conferences and exhibitions
Large scale conferences of umbrella organizations in the rubber industry were organized in many different countries and at a very high frequency. In many of these, the DRIVE4EU partners were already involved. It was therefore not the intention to add to this number but to make use of them and/or to create added value. The DRIVE4EU partners have been invited as guest speakers to the conferences by sending in highly qualitative papers.
DRIVE4EU partners participated to several conferences and workshops with presentations and poster sessions. More information can be found in the tables “list of scientific publications” and “list of dissemination activities”.
Furthermore DRIVE4EU was presented at following conferences and exhibitions:
DRIVE4EU was presented at the EUBCE 2017 – 25th European Biomass Conference and Exhibition in Stockholm in June 2017. Therefor a project presentation area (booth) was rented, and the whole week DRIVE4EU was presented. Stakeholders had the possibility to get information on DRIVE4EU and discuss the whole value chain. Dissemination material from DRIVE4EU was spread to the audience.
A prototype of the Fortezza Flower Power was presented at the Eurobike exhibition in Friedrichshafen, Germany, August 30th to September 2nd 2017 (http://www.eurobike-show.de/ and http://www.eurobike-show.de/eb-de/news/1-350-erwartete-Bike-Teilnehmer-aus-aller-Welt.php Figure 14). Dissemination material from DRIVE4EU was spread to the audience. Press releases were made to promote the production and presentation of the prototype.
At the Bioeconomy Conference Bratislava (BBEC 2016), Slovakia a dandelion car tyre from the previous project EU-Pearls (Figure 19) and the project DRIVE4EU was presented on the 17th of October 2016 (http://www.drive4eu.eu/index.php?cmd=s&id=270&PHPSESSID=8nbrui3s5t3bp2ri5lto922p52). For this conference the leaflet was actualized and printed. The DRIVE4EU leaflets and DRIVE4EU erasers were spread around the participants and gained high attention.
A small exhibition area at the office of the Landesrätin für Wirtschaft, Tourismus, Europa, Wissenschaft und Forschung MMag.a Barbara Eibinger-Miedl (Styria, Austria) was prepared. DRIVE4EU was exhibited from January until end of June 2018.
• Joint internal training workshop in Kazakhstan
To disseminate the existing knowledge on main aspects of T. koksaghyz research, and in order to get access of the Kazakh colleagues to main methods of TKS exploration, the organization of “Joint internal training workshops” for the different target groups like members of the team of the Kazakh partner, breeders and rubber industry, farmers, was foreseen. This enabled a European outreach of the project and provided a good chance for dissemination the project into different regions outside the EU. The main objectives of the training workshops were to transfer the knowledge and latest research achievements and practical experiences on the background knowledge and preliminary results. Training sessions in Kazakhstan were hosted several times over the whole project duration. Joint internal training and workshops on the T. koksaghyz issues (recognition, conservation, population dynamics, related and similar species, ecology, monitoruing) were organized for target groups, such as farmers, local government officials and agricultural researchers in Almaty and the Raiymbek district of Almaty region, Kazakhstan.
The courses took place in Almaty, Kazakhstan, and at the sites with TKS present. Lectures were held on May 28 and May 29, 2014, and the field training from May 30 to June 5, 2014, the latter in the Kegen Region, SE Kazakhstan. On September 8,2017, a training for about 30 farmers was carried out within the “Field’ Day” organized by the government of Almaty region in the field of the TKS agronomy in Turgen village Almaty region, Kazakhstan.
• Final exploitation workshops
Two workshops were organized to exploit the DRIVE4EU results. One happened in Rusthoeve, The Netherlands, with the aim to provide information to farmers interested in Rubber dandelion growing. The other one happens after the project, to inform stakeholders on the outcome of the DRIVE4EU.
Date Theme Location
7th June 2018 Stakeholders meeting Rusthoeve, The Netherlands
19th October 2018 Final stakeholder workshop KeyGene, Wageningen, The Netherlands
Stakeholders meeting at Rusthoeve
The stakeholder meeting “Dandelion, the cultivation of the future” at Rusthoeve, The Netherlands, at June 7, 2018, 14:00 – 17:00 was especially developed for farmers interested in growing Rubber dandelion. The production of cultivation of Rubber dandelion was presented to farmers.
The program was the following
Walk-in with coffee and tea
Welcome to the Rusthoeve Trial Farm, by Charlotte van Sluijs, Rusthoeve
DRIVE4EU in a nutshell, by Ingrid van der Meer, Wageningen UR
The cultivation of dandelion, by Hilde Muylle of ILVO Institute for Agricultural, Food, and Fisheries Research
The breeding of dandelion, by Rolf Mank of KeyGene
During the project lots of questions were recieved by farmers who are looking for a new crop to grow. During the meeting Ingrid van der Meer and Rolf Mank gave a presentation about the history of the project. Hilde Muylle followed with a presentation about the challenges of cultivation of the Rubber dandelion. The conclusion of the meeting was, that there will be a lot of chances but still more questions to answer.
Final stakeholder workshop
The final stakeholder workshop will happen at October 19, 2018. This one day event will be at the KeyGene location in Wageningen, The Netherlands.
The meeting is open for registration from August and a maximum of 140 participants can visit. Besides general presentations and pitches from some of the work package leaders there will be several stalls / stands. So each partner can present their work and results. This will allow informal contact between partners & stakeholders. The registration is available under following link: https://www.eventbrite.nl/e/drive4eu-final-stakeholder-workshop-tickets-49083667571.
Currently the following agenda is scheduled:
10.00 Registration / welcome KeyGene / welcome DRIVE4EU
10.30 Start program
About DRIVE4EU - Ingrid van der Meer - WUR, Coordindator DRIVE4EU
An historical perspective on Rubber dandelion - Peter van Dijk - KeyGene
Short pitches of relevant WP leaders informing on most relevant results:
Breeding Dandelion and analysis of gene flow - WP 2/4, Rolf Mank - KeyGene
Agronomy, harvest and storage - WP3, Hilde Muylle - ILVO
Biorefinery and product uses - WP5/6, Frans Kappen - WUR
Economic analysis and LCA - WP7, Maria Hingsamer - Joanneum Research
12.30 Lunch around market place – each partner presents its contribution, expertise and know-how
14.00 Closing presentation by Fazilet Cinaralp - Secretary General ETRMA
15.00 Drink (& Bites)
• Patent
A patent (DE102016115 894.1) is pending on a new biorefinery design of rubber and inulin extraction. Therefore the first recherché report was received and based on that some details have been clarified and modified according to that report.
Most relevant results and lessons learned:
As a result of the project, the vast majority of the foreground generated during the project corresponds to general advancements in knowledge in the form of lessons learned and improved know-how leading to cost effective and resource efficient processes. As mentioned before for biorefining of rubber and inulin based on Rubber dandelion a patent is pending.
Furthermore results for further exploitation are available in the form of scientific research that can be either be published or may serve as input to new R&D projects. For the DRIVE4EU industrial partners the project has served as an excellent opportunity to test and demonstrate their technologies in order to obtain more reliable and scalable industrial solutions for Rubber dandelion processing.
The following points summarize the most relevant results and lessons learned; that can be extracted from the DRIVE4EU project:
New dandelion hybrids with optimized characteristics
DRIVE4EU developed Rubber dandelions with a higher rubber yield. Therefore a sophisticated system of crossing and selection techniques was used. Several novel hybrid strains were evaluated as most promising ones with the potential of a relatively high rubber producer (up to 18% rubber on dry weight). Stable hybrid lines have the attributes desirable for a rubber plant: high biomass, high percentage of rubber in the roots. Some have additional attributes such as; agamospermy, permanent hybridity and polyploidy of the alloploidy type, no need for pollination. Breeding process is still ongoing to improve the rubber yields even more. A higher production can be achieved by improved agronomy and by breeding bigger plants with more rubber and inulin.
Agronomy
In order to achieve the best agronomical, sustainable and economical production, several trials were conducted to obtain a good opinion on the agronomy of Rubber dandelion in Europe and Kazakhstan. The consecutive steps in general root crop production were explored and demonstrated: sowing (bed preparation, densities, sowing date), fertilization, herbicide treatments, harvesting (harvest machines, harvest date) and storage. Different seed bed systems (ridges versus flatbed) were explored. Planting on flat field resulted in high densities and higher yields, but root morphology was more optimal from planting on ridges. Ridges resulted in longer roots, but a lower plant density and a lower yield on a hectare basis. The field germination was improved by priming and pelleting the seeds. Sowing conditions are optimal in late spring or early autumn if sufficient moisture is available. Herbicides, which can be used in the cultivation of Rubber dandelion, are identified. Further, several harvesting technologies were tested to harvest the roots as clean as possible, with minimized breaks in the roots and minimal harvest of the leaves.
Information on the interaction between cultivated and wild dandelion, conservation of wild dandelion
Crossing experiments between Taraxacum koksaghyz (TKS) and related dandelion species indicate that hybridization is possible under controlled conditions. To determine whether 66 years after the end of seed production of TKS in the Swedish county of Skåne still traces of TKS were present in the environment and TKS genomic fragments could be detected in dandelion relatives, a detailed large scale population genetic study was performed. This study showed that not a single TKS-specific allele was found. This is consistent with the absence of TKS-specific morphological characteristics at the sampled locations. TKS represents an economic plant, an alternative rubber producer, with a potential of world importance. Conservation of TKS is needed because its natural occurrence is confined to a small geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to soil degradation and erosion. As regards the expected trends in future include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing.
Biorefinery design
A biorefinery process was designed and used to extract natural rubber and inulin from Rubber dandelion. For the biorefinery design of rubber and inulin extraction a patent is pending. Depending on the quality of dandelion roots: the biorefinery process is easy to operate; sand is very bad for the process, leading to abrasion of equipment; lower separation efficiency (loss of rubber); and lower purity of rubber. The biorefinery process is an up-scalable process, low manual labour is needed and the efficiency in rubber recovery is high. Inulin is available in a solution, which has to be processed further. Inulin can be used to produce Polyethylene furanoate (PEF), which could substitute the fossil-based Polyethylene terephthalate (PET).
Prototypes made of dandelion rubber
A first bicycle tyre with natural rubber was produced. This particular series of prototype tyres are made with rubber extracted from Rubber dandelion grown and harvested in The Netherlands. The tyre prototype provides better grip than traditional compounds, which is directly related to a higher concentration of natural resin in this particular variant of natural rubber. The better grip was especially on wet-deck, which is a good property for high quality bike tyres for racing bikes. Furthermore, a set of eight passenger car tyres, 195/65R15 Snowtrac 5, were produced containing natural rubber from Rubber dandelion that have been analyzed and tested for their performance in driving experiments. Compound properties were at a comparable level to Hevea natural rubber and also the tyre results indoor and outdoor (snow, wet) were comparable to the reference. These tests were performed in New-Zealand on snow and ice to analyze performance under stringent conditions. Also prototypes of rubber goods in building and agri industry were developed and tested. And finally dandelion rubber was tested in off road prototypes. Further prototypes of other rubber products are made after ending of the project with the rubber extracted in the last part of harvesting. Further extraction and cleaning of dandelion rubber to improve the purity is necessary mainly for the rubber goods because they need a higher purity percentage compared to the rubber used for car and off-road tyres. The mixing cycle of compound and/or reformulation of recipe to compensate for the initial resin content was made. In comparison to natural rubber from Hevea trees: rheological behaviour is similar but more degradation, some mechanical properties are lower, compression set is significantly higher, ageing properties are comparable but from a much lower starting point, processing is much easier. The wet-deck grip is higher for car and bike tyres made with dandelion rubber.
Economic analysis and life cycle assessment
The methodology of economic and environmental assessment was successfully applied to the DRIVE4EU value chain. The main influencing factors of the economic and environmental effects are the cultivation and harvest process step especially fertilizer, plant protective agents and diesel. The assessment showed that the economic viability and environmental sustainability of the DRIVE4EU system could be reached with future improvements. Following future improvements were assumed: e.g. higher yield, higher rubber content, less fertilizer and plant protective use and lower energy demand in refinery. The knowledge of the methodologies used for the assessment was deepened; these further developed methodologies will be used in future research collaborations.
List of Websites:
http://drive4eu.eu/
Contact details are: Project Coordination
- Dr. Ingrid M. van der Meer
- +31 31 74 81 363
-Ingrid.vanderMeer@wur.nl
Dissemination Leader
-Mag.a Maria Hingsamer
- +43 316 876 1421
-maria.hingsamer@joanneum.at
Furthermore, project logo, diagrams or photographs illustrating and promoting the work of the project (including videos, etc...) as well as the list of all beneficiaries with the corresponding contact names can be submitted without any restriction.
Natural rubber (NR) is an essential renewable material for more than 40,000 products essential to building, medicine, transportation industries. In many applications NR cannot be replaced by synthetic rubbers. At the moment NR is harvested exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in South East Asia. NR consumption is forecasted to increase significantly and will increase from 11.2 MT in 2012 to 16 MT in 2020, pushing upwards market prices.
Increasing NR demand can only be complied with by increasing the acreage of rubber tree plantations, but this may be hindered by sustainability issues, including sustainable land use (deforestation), availability of cheap labour, and control of potentially devastating fungal diseases (South American leaf blight). For their NR supply Europe fully relies on imports. Considering the future market developments and related sustainability issues, European rubber manufacturers are urgently looking for resource diversification.
In an earlier EU project on natural rubber, we already demonstrated the quality of natural rubber produced by Rubber dandelion (Taraxacum koksaghyz, TKS). An advantage of TKS is that up to 40% of its root biomass comprises inulin. Inulin is a polymer of fructose, an excellent resource for furan type chemicals and polymers. The main objective of DRIVE4EU was to turn TKS production into a valid business case by developing concepts for valorising rubber and inulin.
TKS is a wild, non-domesticated plant, with a relatively low yield potential. EU-PEARLS resulted in good quality (dry) rubber and two car tyres, and a proof of concept of the rubber extraction process, plus the development of breeding tools for TKS. All essential key elements of the whole production process were in place: the quality of the rubber is good, the extraction method has been sorted out on lab scale, the first breeding tools were set up. The only part that will enable the real demonstration of the viability of Rubber dandelion as new European natural rubber and inulin source, is the scaling up of each individual step in the production chain. This means that in this follow-up demonstration project we needed to scale up all levels in the production chain of NR from TKS, and to valorise as much as possible of the TKS biomass in order to make an economical feasible production chain. In DRIVE4EU TKS cultivars (prototypes) have been developed that produce more total biomass and more rubber. We have optimised the agronomical conditions for growth and seed production (both technical and non-technical) and developed technology for harvesting on large scale, and designed machinery for optimal extraction of the two products, rubber and inulin. The quality and properties of rubber and inulin in different applications was investigated and turned out to be of good quality. Finally, an economic analysis of the whole rubber production chain was made.
The main goals of DRIVE4EU were: (1) plant genotypes with high root biomass, high rubber and inulin yield, (2) seed batches for agronomic tests and large scale demo field trials, (3) new agronomical methods to optimize cultivation and harvest of Rubber dandelion, (4) ecological analysis of the gene flow and competition between cultivated and wild dandelions leading to optimal planting protocol to prevent in- and outcrossing, (5) optimised extraction and purification protocol and machinery of valuable products from TKS-roots: rubber, inulin, and rest material, (6) demonstration of an economic viable and robust production chain and end product uses. All these goals have been reached, showing the success of the DRIVE4EU consortium and the opportunity for Rubber dandelion as new sustainable rubber and inulin crop for Europe.
Project Context and Objectives:
Introduction
Natural rubber (NR) is a unique biopolymer that is essential for the building, medicine, personal care and transportation industries. In many applications, NR cannot be replaced by synthetic – petroleum – rubber (SR), because the high molecular polymer length of NR cannot be matched by SR. At the moment, NR is harvested almost exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in Southeast Asia, meaning that Europe largely depends on imports from Southeast Asia.
The world market for NR increased from 4.4 Mton in 1985 to 11.2 Mton in 2012. Based on forecasts of the International Rubber Study Group (IRGS), NR consumption is expected to reach 16.5 Mton in 2020, with the tyre industry accounting for 12.6 Mton and general rubber goods industry for 3.9 Mton. Since NR cannot be replaced by synthetic rubber, access to natural resources is thus becoming increasingly important.
In the current situation, increasing NR demand can only be complied with an increasing acreage of rubber tree plantations. However, the rubber tree suffers from a number of threats and drawbacks:
• The rubber tree plantations have very limited genetic variability, which results in threats by pests and disease, most notably South American Leaf Blight (SALB). Rubber production is geographically limited to tropical zones mainly in South-Asian countries (80% of which in Malaysia, Indonesia, and Thailand). For now, SALB has been kept out of Asia by a strict quarantine. However, SALB and other plant diseases are threats to a strategically important material.
• Rapid increases in rubber demand, especially in rapidly growing large economies such as China and India, have caused volatile prices. Moreover, existing rubber tree plantations are being replaced by palm oil plantations. In the long term, production from the rubber tree may not be sufficient to cope with increasing demand.
• Climate change threatens agriculture worldwide. Southeast Asia is one region predicted to be especially vulnerable, as detailed by the Economy and Environment Program for Southeast Asia (EEPSEA). High rubber prices are e.g. due to exceptional drought in Southern China and Northern Thailand, Laos, and Vietnam, while rains disrupted tapping in Indonesia and Thailand. These events may or may not be early manifestations of climate change, affecting natural rubber production, but are at least illustrative of possible climate related risks.
• Rubber tapping depends on cheap manual labor, leading to increasing production costs and difficulties to hire tappers as the producing countries develop their economies.
The above shows very clearly that, in order to reduce the dependency of the European industry on the rubber tree and on Southeast Asia, alternative sources of NR should be developed. Diversification of NR sources will strengthen the competitive position of Europe.
EU-PEARLS, which finished in 2012, was a successful FP7-project (coordinated by DLO) aiming at the development of two alternative NR sources for Europe. This research-project investigated the possibilities to produce rubber from 1) guayule and 2) the Russian dandelion (Taraxacum kok saghyz, TKS). It was shown that both crops are able to produce high-quality rubber, but they differ considerably in breeding, cultivation, harvesting and rubber extraction methods. TKS showed the best potential for industrial application, because of the following advantages:
• The rubber from the roots of TKS was demonstrated to produce a rubber which matches the quality of the Hevea rubber, which provides opportunities for high performance products in building and transport sectors.
• TKS can be grown in temperate climate regions, in particular East-European regions with a very large though still under-exploited agricultural potential.
• TKS is an annual crop, which will allow yearly harvest of the full biomass, thus permitting to generate additional economic value by valorising other biomass components. Moreover an annual crop can be plugged in existing crop rotation systems.
• TKS is much easier to breed: because of the short reproductive cycle (2-3 new generations per year), low diploid number of chromosomes and the possibility for sexual reproduction.
• TKS can be easily harvested: existing chicory root harvesting machines can be used.
• The TKS root biomass comprises, next to 10-15% NR, up to 40% inulin. Inulin is a polymer of fructose, an excellent resource for furan type chemicals and polymers. Inulin can be extracted using hot water (allowing a biorefinery process that can be operated without the use of organic solvents).
One of the aims of EU-PEARLS was to increase the productivity and the quality of TKS rubber. This aim has been achieved and EU-PEARLS resulted in good quality (dry) rubber, proof of concept of the rubber extraction process and conversion of NR in two car tyres. Another result of EU-PEARLS was the development of breeding tools and the formation of hybrids between TKS and more vigorously growing dandelion species. For TKS, proof of principle was obtained on an efficient extraction process for rubber on lab scale and on small pilot scale. Crude rubber samples from TKS were used to produce the first sets of (two) car tyres which are currently subjected to an extensive testing program. The first result showed that some aspects, e.g. wet grip of the tyres were equal or even superior to conventionally produced tyres.
As we now know, within the extraction-process there is also room for the extraction of valuable by-products (inulin). Inulin is the main (even more abundant than NR) biomass component of TKS, and an excellent resource for green chemicals. Inulin can very easily be hydrolysed into fructose. Fructose in turn is the most efficient starting point for the production of 2,5-furandicarboxylic acid (FCDA), a biobased alternative for the ubiquitously used petrochemical terephthalic acid (TA).
Taraxacum koksaghyz (TKS)
TKS is a wild, non-domesticated plant species, and therefore has as relatively low root (the main source or NR) and rubber yield. TKS was cultivated on a large scale in the Soviet Union between 1931 and 1950, as well as in the United States, the UK, Germany, Sweden and Spain during World War II as an emergency source of rubber when supplies of rubber from Hevea brasiliensis in South East Asia were threatened. During this time period, the highest yields achieved in the U.S. were 110 kg of rubber per hectare, while the USSR achieved yields of 200 kg of rubber per hectare. With the conclusion of World War II and the return of affordable Hevea brasiliensis rubber, the majority of T. kok-saghyz programs were discontinued.
When the EU-PEARLS project was started, TKS had not been grown for more than 50 years and worldwide germplasm collections were lost or contaminated with other poor rubber producing dandelion species. New true TKS germplasm was collected in two expeditions to eastern Kazakhstan for use in EU-PEARLS.
DRIVE4EU
The DRIVE4EU-project was a logic continuation of the successful EU-PEARLS project. In order to bridge the gap between research and the market, and to commercialise the research results, DRIVE4EU aimed to demonstrate the technical and economic feasibility and potential of TKS. The demonstration included two important innovations:
• Scaling-up of each individual step in the production chain: breeding, seed production, cultivation, extraction of raw material (NR and inulin), and conversion of raw materials in products.
• Extraction of inulin as valuable compound (besides NR). This concept was not adressed in the EU-PEARLS program, but newly introduced into DRIVE4EU. The reason is that economically sustainable production of NR by TKS, also requires the valorisation of additional biomass components.
All essential key elements for this demonstration project were in place: germplasm had been collected and multiplied, the breeding tools were set up, the first hybrids were produced, the NR extraction method was sorted out on lab scale and the quality of the TKS rubber that has been found was very good. Though DRIVE4EU introduced a seemingly new concept - inulin as building block for green chemicals - all essential knowledge to extract and valorise inulin as the second main biomass component was available in the DRIVE4EU-partnership.
The strategic objective of the DRIVE4EU-project was to establish, and demonstrate the economic validity of a European production chain for natural rubber (NR) and inulin as building block for green chemicals, using Russian dandelion (Taraxacum koksaghyz, TKS) as a production platform.
In DRIVE4EU we continued developing TKS cultivars (prototypes) that produce more total biomass and more rubber. We optimised the agronomical conditions for growth and seed production (both technical and non-technical). We developed technology for harvesting and increasing the extraction efficiency of the two main products, rubber and inulin. Hybrids produced in EU-PEARLS were used for this, including the developed breeding tools. Hybrids were grown at different locations in order to investigate the ‘genotype x environment’ interactions. The quality and properties of rubber and inulin in different applications has been investigated. Finally, an economic analysis of the whole rubber production chain was made.
The economic optimization of the cultivation of TKS will make the EU less dependent of NR imports (resource diversification) and has the potential to create many new jobs in Europe. DRIVE4EU will boost the European economy, because it provides the EU with a valuable business case to create extra economic value from available land.
Specific objectives:
The specific objectives of DRIVE4EU were:
• To create TKS plants with higher productivities and to muliply new genotypes via seeds (WP2).
• To produce enough seed lots for large production fields (WP2).
• To develop improved agronomical methods for optimized cultivation (WP3).
• To establish the best methods to harvest and store TKS-roots (WP3).
• To gain knowledge on gene flow and competition between cultivated TKS and wild dandelions (WP4).
• To design a biorefinery process that optimally uses all valuable products from TKS-roots (WP5).
• To demonstrate the quality and applicability of NR and inulin by developing prototype products from these biomass components (WP6).
• To proof the economic viability of the TKS-business case (WP7).
• To inform industry about the demo-results and raise awareness among the wider European public (WP8).
The economic objective of DRIVE4EU is to prove the techno-economic viability of NR from TKS as a business case and to stimulate the commercial exploitation of the project results.
The political objective is to make the European Union less dependent on imports from Southeast Asia, thereby increasing the competitiveness of Europe and boosting the European bio-economy.
Industry-driven
This demonstration project was primarily driven by industry: several European industrial organisations have recognized the potential of the TKS as a new and European source for NR. A competitive, domestic source for the production of NR will substantially decrease their dependence on imports from Southeast Asia.
The development of a solid and viable business case in WP7 will facilitate the establishment of a successful, large scale production chain. The industrial activities that together represent the whole TKS production chain. They coincide with the WPs 2, 3, 5 en 6 of DRIVE4EU.
The industrial partners of DRIVE4EU, who are the initiating and driving force behind the project, were represented in three of the four steps of the production chain:
• KeyGene NV (NL); breeding and biotechnology (WP2).
• Syral S.A.S. (FR); extraction and processing inulin and fructose based products (WP5).
• GEA Westfalia Separator Group GmbH (DE); extraction apparatuses (WP5).
• NETSZCH Feinmahltechnik GmbH (DE); machinery for NR extraction (WP5).
• Apollo Tyres Global R&D B.V. (NL); conversion of NR into car tyres (WP6).
• MITAS a.s. (CZ); conversion of NR into off road tyres ( agro, industrial, moto, small aircrafts etc.) (WP6).
• Trelleborg Sealing Solutions Kalmar (SWE); conversion of NR into polymer-based building products for sealing, damping and waterproofing (WP6).
With respect to the crop cultivation (WP3), no industrial partners were currently involved, but we expect that this activity will be taken over by industrial parties after completion of the DRIVE4EU-project.
DRIVE4EU is concerned with the development and application of ‘industrial biotechnology for the production of high-value products’, in this case NR and inulin. In DRIVE4EU, the research results of EU-PEARLS were further developed, scaled-up and demonstrated in order to stimulate the ‘commercialisation of these research results’. This project will ‘bridge the gap between research and market, while keeping a pre-compeptititve nature’. The high representation of industry enures that the ‘EU-support is primarily aimed at industrial participants’, whereas the research participants were more supportive. The project included a ‘detailed economic viability check’ and the development of an exploitation plan. The project contributes to the European competititveness by introducing a viable, biotechnological alternative for NR, which can be produced in Europe.
Project Results:
Background
Natural rubber (NR) is an essential renewable material for more than 40,000 products essential to building (adhesives, sealants), medicine (gloves, tubing), and transportation (matting, tyres) industries. In many applications NR cannot be replaced by synthetic rubbers. At the moment NR is harvested exclusively from the rubber tree (Hevea brasiliensis) of which 90% is grown in South East Asia. Worldwide NR consumption is forecasted to increase significantly. At the moment the EU is completely dependent on imports of NR.
The successful EU-PEARLS project, which finished in 2012, demonstrated the viability of a new NR producing concept: Russian dandelion (Taraxacum koksaghyz , abbreviated TKS). Not demonstrated in the EU-PEARLS project, but of equal importance in the construction of the TKS business case, is the fact that TKS is also a promising new crop for biomass derived building blocks for the chemical industry via the production of inulin.
The strategic objective of EU-DRIVE was to demonstrate the economic potential of a European production chain for natural rubber and inulin as building block for green chemicals, using TKS as a dual purpose production platform.
To reach the objective a strong consortium of eight industrial partners and five research organisations from eight EU countries and Kazakhstan was constructed with a very broad background from bioscience to the rubber industry.
The main deliverables of DRIVE4EU were: (1) plant genotypes with high root biomass, high rubber and inulin yield, (2) seed batches for agronomic tests and large scale demo field trials, (3) optimized cultivation and harvest methods for TKS, (4) ecological analysis of the gene flow between TKS and wild dandelions, (5) scaled-up and optimised extraction and refinery protocol for TKS NR and inulin, (6) testing and application of TKS NR and inulin in end product uses, (7) demonstration of the economic viability of the TKS production chain for NR and inulin.
1. Results on plant genotypes with high root biomass, high rubber and inulin yield
The approach to the Taraxacum koksaghyz (TKS) improvement reported in this treatise is a repeated crossing with TKS as a mother plant and with related polyploid agamospermous dandelions as pollen donors. The acquisition, characterization and a detailed analysis of several pollen donors, and the first series of crosses highlighted two pollen source as the most promising germplasm. It was T. brevicorniculatum (TB), a triploid apomict with two genome copies of TKS and one from unknown source, and a 202PEC sample, a tetraploid also closely related to TKS. We used a sophisticated system of cultivation and crossing techniques, with early characterization of progenies by means of FCM, rubber and inulin quantification. The rubber quantification is based on a newly adjusted technique suitable for very small samples of root tissues. All the classes of hybrids and wild plants were analysed for both rubber and inulin, and summary data are given. Two hybrid strains were evaluated as most promising ones: one of the TKS x TB parentage, with a high inulin content, the other of the TKS x 202PEC parentage, the latter with the potential of a relatively high rubber producer. These two stable agamospermous hybrid lines share the attributes desirable for a rubber plant: high biomass, agamospermy, permanent hybridity and polyploidy of the alloploidy type, no need for pollination. Moderate rubber amounts in the selected lines vary, mainly because of the sensitivity of the quantification method, and regularly exceed 8-10 % DW. Pending the results of field trials, this part of the project succeeded in developing a basis for the new rubber crop.
Since the 1930s, Taraxacum koksaghyz is considered as a possible alternative source of natural rubber (Kirschner et al. 2013) to replace Hevea brasiliensis (Euphorbiaceae). Along with the classical improvement programmes developed for T. koksaghyz (TKS, for summary, see Ulmann 1951), there is a long-term programme involving hybridization of TKS with related congeners. Taraxacum koksaghyz as a crop plant has a number of unfavourable features that are to be improved: low biomass, a complicated root morphology, very variable rubber content, a need for pollination / insect pollinators etc. There are three basic philosophies for the improvement of a rubber producer based on TKS, if we disregard the GM. First, it is a continuation of the standard selection programme (with selection focussed on biomass, root morphology, rubber concentration in latex and the flowering time). The second approach is based on the experimental hybridization between TKS and another diploid sexual congener, e.g. sexual T. officinale, with molecular characterization and selection from within hybrid progenies and further backcross generations, in order to get a sexual cultivar with desirable attributes. The last approach again involves repeated experimental hybridization, this time with a range of agamospermous polyploid congeners, in order to get an agamospermous polyploid hybrid with permanent heterosis, i.e. with high biomass, reasonably high rubber and full seed set without the need of pollination. The latter approach was used within the WP2 of the DRIVE4EU project.
TKS is a plant with relatively low biomass, a necessity of sexual reproduction in the diploid, substantially branched roots, and a narrow ecological amplitude. The hybridization programme was set up to obtain hybrids with the following attributes: high biomass (a result of extreme levels of heterozygosity in polyploid hybrids, permanently fixed by agamospermous reproduction), taprooted general habit, agamospermous reproduction (stabilized diplospory, Taraxacum type, pollination not required), allopolyploid genome (permanent heterosis), and a wider ecological amplitude (as a result of several copies of metabolic enzymes with a range of reaction optima). In view of these rather limiting conditions for the paternal material, some of the pollen donor taxa were selected as priority sources of paternal germplasm, after excluding several others, see Material and Methods. We therefore limited our advanced experiments to two pollen donors: Taraxacum brevicorniculatum (TB), a triploid apomict characterized by relatively low to moderate rubber content, high biomass, triploidy and the genome composed of two TKS genome and one unknown one (Kirschner et al. 2013; since the EU-PEARLS, a number of papers using TB as a model rubber plant appeared but these are not cited here as they are outside the scope of the present report). The other pollen donor is an undescribed agamospermous tetraploid, also parapatric to TKS under natural conditions, with a rubber content slightly higher than in the latter polyploid. The main aim of the crossing programme therefore was to obtain a rubber productive, vigorous, polyploid agamospermous, high biomass hybrid.
From the extensive hybridization programme we obtained several hybrid lines with a remarkably high rubber percentage in roots. These are now analysed in other partner's labs to check the existing rubber figures and to characterize the hybrids from the genomic viewpoint. Two of the selected hybrid samples share the following desirable attributes: (a) high biomass, (b) rubber content comparable to or slightly lower than that of TKS, (c) polyploidy, and (d) agamospermous reproduction. Thus, this part of the IBOT participation in the project succeeded in developing a basis for the new rubber crop.
The first line of the TKS x TB parentage is also enormously high in inulin (often over 60% DW) but its rubber performance is to be tested under standard agricultural conditions. The other line, selected from multiple progenies of the TKS x 202PEC parentage, also requires standard field testing. Both require further analysis as to their root morphology and biomass variation.
The hybrids have a potential of 2-5 times higher biomass, so that the overall rubber yield is expected to be reliably higher than that of TKS. The hybrid lines also do not suffer from the possible lack of pollinators (TKS is entomogamous).
2. Results on seed batches for agronomic tests and large scale demo field trials
KeyGene has multiplied its EU-PEARLS seed stock of wild TKS to provide seeds for the agronomy plots (WP3) and the large demonstration fields (WP6). At the start of DRIVE4EU approximately 2500 seeds were available. These seeds are used for seed amplification in the seed nursery. The number of seeds available for agronomic tests were limited in the first years due to the limited multiplication rate.
During the seed production we ran into several issues as drought, early flowering (prior to the availability of pollinators), hail storm and flooding. In the end most seed multiplication has taken place in a controlled greenhouse environment. In addition seed harvesting methods were not yet developed; simple but effective methods were developed to harvest the seeds. Seed processing was executed at the KeyGene seedlab and by outsourcing it to experienced service providers. Seeds provided to WP6 were for a part primed (and pelleted).
Seeds were provided to the WP6 partners mostly in accordance to the deliverable. However a delay occurred in 2016 due to bad weather conditions. In total, for large scale demonstration fields for WP 6 5000 seeds were provided at month 16, and 750000 at month 28 and the same amount at month 40.
Seed production started at first in combination with the breeding program and was continued from 2015 onwards in shielded fields using bumble bees or naturally available pollinators of TKS germplasm, and in greenhouses using bumblebees. Inflorescences were collected and seeds were processed and cleaned. Seed production from the TKS germplasm stock available was executed in 2015 at two different open field locations. This concerned small patches of approximately 600 plants each in Achterberg (open field) and Elburg (mesh tunnel). Seeds were harvested manually successfully. The locations had different soil types.
In 2016, seed production from the TKS germplasm available was executed at two open field locations. The locations had different soil types and differed in size. One location was an fenced open field of 10.000 plants (Overloon), one had an open field at a small farm (600 plants, Achterberg). The open fields used both natural occurring pollinators in 2016. The fields both suffered from severe weather conditions in 2016. The Overloon field, harbouring the large production field, got flooded in June 2016 and the location as well as the plants have to be regarded as being lost. The field in Achterberg suffered from heavy rain earlier in the year. As the soil kept being wet a large number of overwintering plants got lost. This location was abandoned at the end of 2016.
- In order to reach the targets a new greenhouse location (Huissen) was started up in early 2016. In this location a number of tents were put up in order to grow the lines separately without intercrossing between selections. In order to produce enough seeds, seeds were sown on plugs. Young plants were vernalized and only good plants were grown in the seed production tents. In total 5 tents each harbouring 1000-5000 plants were used. The greenhouse seed production made use of bumble bees successfully. Material for specific traits was harvested separately (vernalisation need, leaf shape). These selections had been top-crossed. The seeds were partly being processed using an acquired seed brushing machine, sieving, and subsequent cleaning using a seed air separator. Seed harvesting is partly done with a self-made seed collecting device.
- Due to large losses in the open field productions additional seed production has been started up in June 2016. A total of 10,000 seeds of two selections were sown for seed production in large tents (200 m2) in the Huissen greenhouse. In total 18,000 plantlets have germinated and are vernalized to induce flowering. The seed production was successful in spring and summer 2017.
Those first seed batches were cleaned at the KeyGene seedlab and partly by outsourcing it to experienced service providers due to the high volume. Due to the high volume material available grading of the seeds was possible (on seed caliber) thus higher quality seed could be provided to WP6. The material was stored, and sufficient material was available. Finally, only the Huissen greenhouse location was continued after 2016. Plants remained in the soil for subsequent harvesting.
- Priming and pelleting of seeds was successful as germination rates increased dramatically. A partnership with Incotec safeguarded high germination rates.
The seed batches delivered to the partners were:
• ~400 k primed/pelleted seeds were provided in June 2016
• ~750 k primed/pelleted seeds were provided in May 2017
• ~100k unprimed seeds were provided June 2017
3. Results on optimized cultivation and harvest methods for TKS
Summary
Although Taraxacum kok-saghyz was cultivated in the Soviet Union and other countries until the 1950’s, the agronomy of the rubber dandelion using current technology was rather unknown at the start of the Drive4EU project. During the project we explored and demonstrated the consecutive steps in general root crop production: sowing (bed preparation, densities, sowing date), fertilization, herbicide treatments, harvesting (harvest machines, harvest date) and storage, in Belgium, the Netherlands and Kazakhstan. Four years of setting up TKS production fields revealed that TKS agronomy should rely on sowing in late spring with naked or pelleted seed. Ridges or raised beds are preferred as these promote root formation and yield longer roots. Plant densities should be high but depend on the sowing and seed bed preparation. Test with densities of 375k/ha yielded the highest root yield (3.3 ton DM/ha). TKS has a low fertilizer demand (50 to 70N) and herbicides to be used in TKS were identified. These need further testing for approval. Harvesting experiments showed that machinery should be adapted to the required large digging depth and the branched root shape of TKS, in order to reduce root damaging. Current (mechanical) cleaning devices on harvesters are not well suited for this root shape, leading to high amounts of tare in the harvested product. An additional cleaning step between harvest and bio-refinery is at this moment still required. Breeding of TKS towards a large tapered root and cultivation on ridges could improve the harvesting process. The Drive4EU consortium made the step from field trials at small scale (100 – 200 m²) to large scale (4 ha). Further yield enhancement is expected through improvement at the level of field germination and harvesting. This can be achieved by agronomic innovations but also at the breeding level such as working on root morphology to enhance the harvest efficiency.
Introduction
The first step which was explored was the installation of the field. Current tap root crops such as cichory are grown on ridges, which promotes the growth of a straight tap root without branches. However sowing on ridges implements a lower plant density than compared to flat field sowing. During the project we compared the tap root shape when grown on ridges versus flat field.
TKS agronomy preferably relies on direct sowing as planting pregerminated seedlings is too expensive. To secure high plant densities, one has to rely on good field germination of naked seed. If naked seed is not suitable for direct sowing with current technology due to various reasons such as incompatible seed dimensions for mechanical sowing, low field germination due to lack of moisture for a sufficient time or necessity of light, ... , naked seeds can be primed (break-down of dormancy) and/or pelleted to allow direct sowing with current technology and conditions. We investigated the advantages of pelleted and/or primed seeds versus naked seeds.
A second aspect of TKS agronomy is the fertilization and weed control. As TKS in not yet a registered crop, no registered herbicides are available to be used in TKS production. We tested a range of herbicides for their compatibility with TKS crop production. The tested herbicides include pre and post germination herbicides.
Finally, the crop has to be harvested and stored in such a way that the bio-refinery can process the harvested roots for rubber and inulin extraction. The scale-up of the bio-refinery revealed some burdens to be solved at the level of harvest and post-harvest methodology. Especially the presence of above ground material and soil in the harvest hampered an efficient bio-refinery system. Therefore, different harvest and post-harvest treatments such as haulm killing, washing, drying and sieving of roots were tested in order to improve the quality of the harvest for bio-refinery purposes.
In the last years of the project we made the step from small scale field trials (6m² plots) up till large scale demonstration fields (up to 4 ha), which allowed also to scale up the machinery (planting, weed control, harvest, cleaning of harvest, ...).
Conclusions
Four years of setting up TKS production fields revealed that TKS agronomy should rely on sowing in late spring with naked or pelleted seed. Ridges or lifted beds are preferred as these promote root formation and yield longer roots. Plant densities should be high but depend on the sowing and seed bed preparation. Test with densities of 375k/ha yielded the highest root yield (3.3 ton DM/ha). TKS has a low fertilizer demand (50 to 70N) and herbicides to be used in TKS were identified. These need further testing for approval. Harvesting machinery should be adapted to the required large digging depth and the branched root shape of TKS, in order to reduce root damaging. Further development of adapted cleaning units on the harvesters to reduce tare, cultivation on ridges or raised beds, and breeding towards large tap roots could facilitate an efficient harvest. The Drive4EU consortium made the step from field trials at small scale (100 – 200 m²) to large scale (2 ha). Further yield enhancement is expected through improvement at the level of field germination and harvesting. This can be achieved by agronomic innovations but also at the breeding level such as working on root morphology to enhance the harvest efficiency.
4. Results on ecological analysis of the gene flow between TKS and wild dandelions
Summary analysis gene flow
Crossing experiments between Taraxacum koksaghyz (TKS) and related dandelion species indicate that hybridization is possible. This may result in interspecific gene flow in regions where TKS is cultivated and in SE Kazakhstan where TKS is growing in the wild. Both situations were investigated in this report. To determine whether 66 years after the end of seed production of TKS in the Swedish county of Skåne still traces of TKS were present in the environment, a detailed large scale population genetic study was carried out. At different distances to two fields where between 1947 and 1950 tens of millions of TKS seeds were produced, in total 576 wild common dandelions (Taraxacum officinale, TO) in 21 populations were sampled. These plants were genotyped for 10 codominant TKS- or TO-specific KASP DNA markers. In total 14652 alleles were typed. Not a single TKS-specific allele was found. This is consistent with the absence of TKS-specific morphological characteristics at the sampled locations. Although this negative result in the sample set cannot exclude the possibility of hybridization and introgression absolutely, it is clear that the impact of TKS seed production after almost 70 years in Skåne has to be very low. This result may be extrapolated to regions where no sexual diploid Taraxacum species occur, which is in western Europe north of 52 degrees latitude. In its native range in SE Kazakhstan TKS is spatially isolated from related dandelion species by habitat differentiation. However, at disturbed sites TKS may grow intermingled with other dandelion species. Two of such disturbed locations were investigated. From the combined analysis of ploidy level, reproduction mode and multilocus KASP genotypes, we infer that there is no indication for gene flow between TKS and sympatric Taraxacum species in natural populations in SE. Kazakhstan. TKS populations in SE. Kazakhstan are therefore not likely to be threatened by gene swamping caused by other dandelion species.
Artificial pollinations have shown that interspecific crosses between Taraxacum koksaghyz (TKS) and other dandelion species are possible, despite considerable differences in genome size. Koroleva (1939) successfully crossed TKS with other sexual diploid dandelions. TKS can also be crossed with sexual diploid common dandelion, Taraxacum officinale (TO) (P. van Dijk, personal observations) and with apomictic polyploid dandelions, for example triploid Taraxacum brevicorniculatum (TBR)(J. Kirschner personal communication). Małecka (1971) found natural hybrids between Taraxacum koksaghyz and T. officinale in the botanical garden of Jena, where both parental species were growing next to each other. This suggest that at places where TKS grows naturally or is cultivated in the vicinity of wild related dandelions, interspecific gene flow between dandelion taxa is possible. Whether this leads to introgression of TKS genes into the gene pool of wild dandelions and visa versa depends on the breeding systems, ecological differentiation and on many population genetic parameters, e.g. selection, genetic drift and assortative mating. While introgression is hard to predict, it may be measured by genetic marker analyses. In DRIVE4EU two of such sympatric situations were studied that are relevant with respect to gene flow between TKS and wild relatives: 1. two sites in southern Sweden where TKS seeds were produced almost 70 years ago; and 2. Two disturbed sites in south Kazakhstan within the native range of TKS, where TKS is growing in the wild intermingled with related dandelion species.
Discussion and conclusions gene flow
The situation in Skåne offers a unique opportunity to investigate the long-term impact of the cultivation of TKS on the gene pool of local wild dandelion populations. The seed production of TKS between 1947 and 1950 is documented in Joseffson (1953). Based on these data it can be anticipated that 10’s of millions of TKS seeds have been dispersed into the environment. The locations of the former seed production field were found back in May 2016 and populations of wild dandelions were sampled according to a scheme taking the high dispersal capacity of dandelion seed into account.
No wild growing TKS plants or dandelion plants with partial TKS morphology were found in the vicinity of the former seed production fields. The dispersal of seeds in the environment has definitively not led to large scale establishment of TKS populations 70 years after the seed production was abandoned. This may be due to the fact that TKS is not a very competitive plant species, as is clear by the fact that cultivation suffers a lot from competition by weeds.
TKS and native triploid apomicts may also have hybridized thus generating new polyploid apomictic clones. Backcrossing of these clones to sexual TKS could generate new apomictic clones with a greater TKS genetic background. Therefore the gene pools of wild dandelion populations were investigated with codominant species-specific DNA markers. Native dandelions that were collected are likely all to be triploid, perhaps some are tetraploid. If we exclude the atypical Contig2608-372 marker, a total of 4884 KASP assays have been successfully run (Table 5), each genotyping a single locus. Assuming that the native dandelions are triploid, this is equivalent to 14652 alleles. Among this number not a single TKS specific allele could be detected. Restricting this analysis to the populations within 2.5 km distance, it can be concluded that among 336 plants, or 9072 genes analyzed, not a single TKS-specific gene variant was found. This is consistent with the absence of TKS morphological characteristics at the sampled locations. Although this negative result in the sample set cannot exclude the possibility of hybridization and introgression absolutely, it is clear that the impact of TKS seed production after almost 70 years in Skåne was very low.
To what extent can these results be extrapolated to TKS cultivation for rubber? Wild dandelions in Skåne are triploid. Because these plants are obligate apomicts, they cannot be fertilized by pollen from TKS. Wild triploid apomicts produce only small amounts of viable pollen, because pollen meiosis is highly disturbed as a consequence of an uneven number of chromosome sets. The conditions at Skåne are thus unfavorable for hybridization and introgression. On the other hand flowering in rubber production fields will be much lower than in seed production fields. Since flowering may reduce rubber production flowering in rubber production fields flowering of TKS will be reduced as much as possible (e.g. by using vernalization dependent varieties and well-timed harvesting). In Europe, north of 52 degrees latitude sexual diploid dandelions are extremely rare. South of 52 degrees latitude sexual diploid dandelions become more common. Here in principle bi-directional gene flow between TKS and wild dandelions is possible. When TKS is grown in these regions it may be necessary to investigate the regional geographic distribution of wild diploid sexuals and triploid apomicts if gene flow is a concern.
Introgression and conservation of wild TKS in Kazakhstan
This part of the study was carried out to obtain a better understanding of the conservation status of TKS in its native range. Normally TKS is restricted to particular habitats and this ecological isolation will also result in spatial isolation. However, at disturbed sites this ecological isolation may breakdown, in the worst case resulting into genetic swamping by hybridization and the disappearance of TKS. At two such uncommon sites we investigated if TKS plants were fixed for TKS specific alleles or whether they contained alien alleles. This turned out not to be the case; even the putative morphological hybrid did not show signs of introgression. It can be concluded that in addition to ecological differentiation other gene flow barriers restrict the introgression of non-TKS genetic material.
This large scale detailed study could not find any traces of TKS in southern Sweden, 66 years after the cultivation for seed production was abandoned. This concerns both the establishment of pure TKS in the wild as well as the introgression of TKS genes in the local wild dandelions. Although this negative result cannot exclude the possibility of gene flow completely it is safe to conclude that the impact of TKS was very low. These results can be extrapolated to future cultivation of TKS in regions where local dandelions are triploid obligate apomicts, but not for regions where diploid sexuals occur. In Europe, north of 52 degrees latitude sexual diploids are extremely rare. South of 52 degrees latitude it may be necessary to investigate the local geographic distribution of diploid sexuals and triploid apomicts if gene flow is a concern. From the combined analysis of ploidy level, reproduction mode and multilocus KASP genotypes, we infer that there is no indication for gene flow between TKS and sympatric Taraxacum species in natural populations in SE. Kazakhstan. TKS populations in SE. Kazakhstan are therefore not likely to be threatened by gene swamping caused by other dandelion species.
Measurements that can be used for conservation of TKS
Taraxacum koksaghyz (TKS) represents an economic plant, an alternative rubber producer, with a potential of world importance. Because it is confined to a small geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future, a conservation is needed. TKS is restricted to an area in valleys of Kegen River, Saryzhaz River, Tekes River and Tuzkol Lake. As regards its habitats, TKS avoids sandy or marshy habitats in the valleys. It is an ecotonal plant thriving between the marshes and dry elevations, mostly associated with loose stands of Achnatherum splendens ("chia") or with meadows near springs dominated by Juncus salsuginosus or J. gerardii. TKS is a sexually reproducing diploid with sporophytic incompatibility and, therefore, obligate outcrossing requiring cross-pollination. Each of its large populations comprises the absolute majority of species' genetic variation. TKS currently exists at more than 30 localities, with only three macrolocalities really rich in TKS plants (Kegen, Saryzhaz and Tuzkol Lake). The condition of the localities is relatively satisfactory, and no emergency measures are needed. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit, after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to the soil degradation and erosion. As regards the expected trends in future, they include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. Also the continuing climatic change might reach a critical limit in this area in future. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing. The conservation plan should be launched at national and regional government levels, and all the local stakeholders should be involved or at least contacted. Continuing research based on the monitoring of water, climate and TKS population dynamics is an integral part of the conservation plan.
Conclusions measurements that can be used for conservation of TKS
1. TKS represents an economic plant with a potential of world importance. Because it is confined to a small
geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future, a conservation is needed.
2. TKS is restricted to a small area in valleys of Kegen River, Saryzhaz River, Tekes River and Tuzkol Lake. Its
occurrence in Xinjiang, China, was documented but not recently, and was confined to the border region. The
occurrence in Kyrgyzstan remains without proof.
3. In terms of ecology, TKS avoids sandy or marshy habitats in the valleys. It is an ecotonal plant thriving between the marshes and dry elevations, mostly associated with loose stands of Achnatherum splendens ("chia") or with meadows near springs dominated by Juncus salsuginosus or J. gerardii.
4. In terms of species biology, TKS is a sexually reproducing diploid with sporophytic incompatibility and, therefore, obligate outcrossing. Its population genetic variation is harboured within populations, so that each large population bears the absolute majority of species' variation.
5. TKS currently exists at more than 30 localities, with three macrolocalities really rich in TKS plants: the Kegen locality, the Saryzhaz locality and the Tuzkol Lake locality. The condition of the localities is relatively satisfactory, and no emergency measures are needed.
6. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit, after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to the soil degradation and erosion (including salt flat formation).
7. As regards the expected trends in future, they include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. Also the continuing climatic change might reach a critical limit in this area in future.
8. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing. The conservation plan should be launched at national and regional government levels, and all the local stakeholders should be involved or at least contacted. Continuing research based on the monitoring of water, climate and TKS population dynamics is an integral part of the conservation plan.
5. Results on scaled-up and optimised extraction and refinery protocol for TKS NR and inulin
Design of a biorefinery process
Summary
Several trials with the goal to design a bio-refinery process to obtain Dandelion Rubber from Dandelion roots were performed. Up-scalable equipment (hammer mill, bead mill and centrifuge) was used and materials were analysed for their properties.
Before milling (hammer mill or bead mill), the roots were cleaned from sand. With a hammer mill, a root pulp was produced that could be pumped into a bead mill.
The bead mill reduces the size of the fibres, but keeps the size of the rubber particles intact or even enlarges them. After several passages, there were no fibres found and the rubber yield looked to be quite good.
Rubber particles could be separated from the brown liquid suspension resulting from the bead mill. It was possible to separate the suspension into a solid phase and a (rather) clear liquid phase with rubber particles using a centrifuge.The rubber fractions were analysed with TGA and GPC. In the current set-up, a bead mill process with 2 or 3 passages seem to lead to the best results, combining separation efficiency, rubber recovery, rubber purity and rubber molecular weight. The polymer (rubber) content as measured with TGA was 81-84% and the molecular weight was 600-700 kDa as measured with GPC.
The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.
Previously, a laboratory ball mill was used to obtain Dandelion Rubber from Dandelion roots. ±20 g dry roots were cooked and put in a laboratory ball mill with ±180 g water. The mixture was ball milled for 1 hour at high speed. Subsequently, the resulting mixture was sieved and the residue contained large rubber particles. The purity of the rubber had to be improved (less acetone-ethanol-extracts, less ash, etc.) to meet the requested requirements.
The laboratory process was scaled up using barrels with larger volumes. However, the barrels were rotating at low speed and the process took some days before rubber particles could be sieved off and purified further. This process also involved a lot of manual labour and wash water. The wash water, probably containing inulin and soluble sugars, was not used further.
For the DRIVE4EU project, the aim is to design an up-scalable process since several tons of wet biomass (roots and leaves) have to be processed. To do so, a process using up-scalable equipment (hammer mill, bead mill and centrifuge) was tested.
Before milling (hammer mill or bead mill), the roots had to be cleaned from sand. During the hammer mill trial at Netzsch Hanau in May 2015, it was decided that the roots will be milled/chopped into large pieces. The sand can be washed away and the large root pieces continue to the next step of the process (pre-milling with a hammer mill). This process was used with FBR equipment to prepare material for next trials (bead mill).
For this trial, dried dandelions were available, harvested by ILVO (DRIVE4EU-WP3 partner) in June 2015. The whole dandelion was harvested, containing leaves and roots. Although the plant was washed at ILVO, they still contained sand, especially in the root collar. The roots themselves are not very thick, but it looks like they contain more rubber than previously. A kettle with a sieve on the bottom was used to clean the roots. The material is stirred and sand can go through the mesh. Sand is removed while draining the water from the kettle. This process is repeated several times to clean the roots thoroughly. Due to the stirring, the roots are chopped a little bit. A centrifuge machine was used to remove excess water. In the centrifuge extra water was sprayed to remove the last sand.
Pre-milling is performed on a similar way as during the Netzsch Hanau trial on May 12 2015. A hammer mill (Pallmann PHM 4-2) is used to reduce the size of the roots. First, the roots were milled and passed through a 12 mm sieve with continuous running water. Dewatered pulp was milled a second time and passed through a 5 mm sieve, again with continuous running water.
In total 150 kg of root pulp (± 10% solids) was prepared from 15 kg of dried roots. A bead mill LME-4 from Netzsch was used. Several tests were performed. Several batches of test material have been tested for their separation efficiency.
A stirred tank was filled with water and the bead mill is started. The slurry with root material was slowly added and pumped through the mill. The ground material (suspension) was circulated back into the tank (circulation) or into another tank (passage). When the suspension is poured over a sieve, the residue contains rubber particles. The rubber material has to be separated from the solids (fibre material). In the suspension, the rubber particles are visible because they are floating on the surface of the liquid. A disc centrifuge is used to separate the rubber from the other solids. This method uses a separation based on density. Spin tests showed that there is a clear separation between the water and solids phase. Rubber particles are floating on top of the water phase. The disc centrifuge can be continuously fed, the solids are collected (dark brown material) and rather clear liquid is continuously coming out.
In November 2015, a centrifuge and decanter trial was performed at GEA in Oelde. Suspensions from the bead mill trial in Selb were used. In a first test, a vibrating screen was used to separate large rubber particles.
Secondly, a centrifuge was used to separate solids (mud) from liquid with small rubber particles. The liquid was poured over the vibrating screen to collect these rubber particles. And during a last test, a suspension was processed through a decanter and solids (mud), liquid and rubber particles were collected.
Conclusions
A biorefinery process was tested in several steps to obtain Dandelion Rubber from dandelion roots.
- (Almost) all sand could be removed prior to milling.
- The slurry prepared with a hammer mill could be pumped through the bead mill.
- Rubber could be separated from the suspension by sieving, centrifugation and flotation.
- Centrifugation tests showed that rubber could be separated from the suspension with the water.
- In the current set-up, 2 or 3 passages through the bead mill seem to lead to the best results, combining separation efficiency, rubber recovery, rubber purity and rubber molecular weight.
o The polymer (rubber) content as measured with TGA was 81-84% .
o The molecular weight was 600-700 kDa as measured with GPC.
The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.
Pilot scale demonstration equipment
Several trials with the goal to design a bio-refinery process to obtain Dandelion Rubber from Dandelion roots were performed. Up-scalable equipment (hammer mill, bead mill and centrifuge) was used and materials were analysed for their properties. The trials performed at several locations resulted in a design of a biorefinery process with a complete line-up of equipment.In the period M24-M36, trials were performed at the location of Netzsch in Selb. For these trials, machinery from Wageningen FBR, Netzsch (Hanau) and GEA (Oelde) was transported to Selb to be able to perform the process semi-continuously at one site.
With the line-up of all this equipment, the partners were able to demonstrate a pilot scale process with pilot scale demonstration equipment.
Previously, a laboratory ball mill was used to obtain Dandelion Rubber from Dandelion roots. ±20 g dry roots were cooked and put in a laboratory ball mill with ±180 g water. The mixture was ball milled for 1 hour at high speed. Subsequently, the resulting mixture was sieved and the residue contained large rubber particles.
The laboratory process was scaled up using barrels with larger volumes. However, the barrels were rotating at low speed and the process took some days before rubber particles could be sieved off and purified further. This process also involved a lot of manual labour and wash water. The wash water, probably containing inulin and soluble sugars, was not used further.
For the DRIVE4EU project, the aim is to design an up-scalable process since several tons of wet biomass (roots and leaves) have to be processed. To do so, up-scalable equipment (hammer mill, bead mill and centrifuge) was tested to perform the process semi-continuously at one site.
Conclusions pilot scale demonstration equipment
A biorefinery process was tested with pilot scale equipment to obtain Dandelion Rubber from dandelion roots.
• Cleaning: kettle with stirrer and sieve combined with vibrating screen
• Pre-milling: Netzsch hammer mill CHM 23/20
• Bead-milling: Netzsch bead mill LME-4
• Separation: GEA decanter with vibrating screen
The trials performed at one location resulted in a biorefinery process with a complete line-up of this upscalable equipment.
Composition of available TKS-lines and their suitability for a biorefinery process
Dandelion roots, harvested by partners in WP2 (Breeding and seed production) and WP3 (Agronomy, harvest and storage), were used by the partners in WP5 (Bio-refinery design) to extract rubber and inulin. The background of the different TKS lines used, agronomy, harvest methods, and storage time/method were evaluated for their influence on composition and bio-refinery suitability. During the trials, it became clear that all types of roots could be processed with efficient recovery of rubber and inulin. Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process. It was shown that the rubber recovery yield was so high that almost all rubber is recovered, independent of the quality of the roots. Also, high concentrated inulin/sugar syrups were obtained. Based on the lab tests performed at WUR, the three partners Netzsch, GEA (WSPC) and WUR developed successfully a refinery process. This process is patent pending. The process was tested and proven with different and difficult raw materials. When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Inulin increases the viscosity too much, so bead milling and separation will become inefficient. In this way, also inulin recovery is improved. Most important is the removal of sand. Sand causes a lot of abrasion in pumps, mills and machines in general, decreasing the efficiency. Sand can attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material.
Dandelion roots, harvested by partners in WP2 (Breeding and seed production) and WP3 (Agronomy, harvest and storage), were used by the partners in WP5 (Bio-refinery design) to extract rubber and inulin.
The roots were different in several aspects:
- appearance (size, branching)
- ratio and amount of the components (inulin, rubber)
- production location and conditions
o in The Netherlands, Belgium or Kazakhstan
o on clay and sandy soils
o flat field or on ridges
- harvesting season (spring, autumn) and season (2014-2018)
- storage (dried, fresh)
The background of the different TKS lines used, agronomy, harvest methods, and storage time/method were evaluated for their influence on composition and bio-refinery suitability. The aim was to evaluate the background of the different TKS lines used, agronomy, harvest methods, and storage time/method for their influence on composition and bio-refinery suitability. The bio-refinery process basically consists of five steps: washing, pre-milling, bead-milling, separation and purification.
During the trials, it became clear that all types of roots could be processed with efficient recovery of rubber and inulin. Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process.
When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Inulin increases the viscosity too much, so bead milling and separation will become inefficient. Therefore a heating and separation step is used as part of the pre-milling step to remove soluble inulin. In this way, also inulin recovery is improved. Higher concentrated inulin/sugar syrups could be obtained (from less than 1° Brix, while at the last trials this concentration was improved up to 6°Brix even up to >13°Brix).
More important is the cleanliness of the roots. Too much weed can block the mills and screens. Fresh leaves also can block mills and screens, and it also prevents easy washing of the roots.
Most important is the removal of sand. Sand causes a lot of abrasion in mills and pumps, decreasing the efficiency. When sand stays too long in the process, it will attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material. Looking at the morphology of a dandelion root it can be seen that the leaves on top cover the root collar where a lot of sand is present. This sand is very difficult to wash away, especially with highly branched roots. Good results are achieved when the root collar is cut with e.g. a clog breaker. It is necessary to process the root collar because it contains a significant amount of rubber.
Conclusions Composition of available TKS-lines and their suitability for a biorefinery process
All types of roots could be processed with efficient recovery of rubber and inulin.
Appearance, rubber content, production location, harvesting season and/or storage did not have an effect on the efficiency of the bio-refinery process. When the roots contain a lot of inulin, it is necessary to remove the inulin prior to the bead milling step. Too much weed can block the mills and screens. Fresh leaves also can block mills and screens, and it also prevents easy washing of the roots.
Most important is the removal of sand. Sand causes a lot of abrasion in mills, pumps and machines in general, decreasing the efficiency. Sand can attach to the rubber, making the separation efficiency in the decanters much lower. It will also increase ash content of the final rubber material.
Based on the lab tests performed by WUR, the three partners Netzsch, GEA (WSPC) and WUR developed successfully a refinery process. This process is patent pending. The process was tested and proven with different and difficult raw materials. It was shown that the rubber recovery yield was finally so high that almost all rubber is recovered, independent of the quality of the roots. Also the inulin or sugar concentration in the separated liquid was improved within the project trials. At the beginning the sugar concentration was less than 1° Brix, while at the last trials this concentration was improved up to 6° Brix even up to >13°Brix.
Large scale samples of dry rubber and inulin (to be used in product development)
During a large scale pilot-trial in February 2018, large samples of dry rubber and inulin were produced to be used in WP6. In February 2018, GEA, Netzsch and WFBR have processed the larger amount of dandelion roots from the Rusthoeve harvest October 2017 to obtain rubber during a large trial at the facilities of GEA in Oelde. Afterwards, WFBR has washed the rubber samples with ethanol. Rubber samples were obtained with a combined weight of 2500 g. Purity of each sample differs slightly. The rubber is divided in three equal portions for Apollo, Mitas and Qew.
Also, large amounts of solubilized inulin were produced of which 50 liters was saved to model the inulin/fructose refinery process. In May and August 2018, an even larger trial was scheduled. The quantity of rubber material extracted was 20 kg.
6. Results on testing and application of TKS NR and inulin in end product uses
Bike and car tyres
In the period 2017 – 2018 three batches of Natural Rubber (NR) from Rubber dandelion have been received from WP5 for further evaluation and prototyping. The first batch was used by ATG for evaluation of in compound properties for bicycle tyres and also for making the first set of bicycle prototypes. The batches 2 and 3 were divided between the partners Apollo, QEW and Mitas and were used for the compound testing and prototyping of car tyres, rubber good and an off road tyre. In this deliverable report, the results for the bike and car tyres are presented.
The compound properties of the dandelion NR in a bicycle formulation were on an acceptable level. Also the prototype bicycle tyres were tested indoor and in a small field evaluation test. The performance of the prototype tyres with NR dandelion was at an acceptable level.
In 2018 the NR dandelion was used in a set of passenger car tyres, 195/65R15 Snowtrac 5. Compound properties were at a comparable level to Hevea natural rubber and also the tyre results indoor and outdoor (snow, wet) were comparable to the reference.
The objective was to create prototype products based upon the rubber extracted from Rubber dandelion (Taraxacum koksaghyz; TKS). Thereto, the basic polymeric properties and rubber material properties after cross-linking have to be assessed. The assessment of the rubber material properties will start with measurements of the purity and the molecular weight of TKS rubber as compared to Hevea and synthetic rubber. The impurities of Natural rubber of TKS will be further investigated on composition and quantity. In a second step, the vulcanization and compounding process of dandelion rubber will be addressed. The basic idea is to evaluate such rubber samples in a standard formulation (100 phr against NR) and in other couple of standard formulations in blends with styrene-butadiene rubber (SBR) and butadiene rubber (BR). The cured samples will be tested for cure kinetics and reversion resistance, hysteresis with a mechanical spectrometer and with a Goodrich flexometer and for several mechanical properties (hardness, Mooney viscosity, etc.) and temperature dependent behavior.
Commercially, compounding modifications are used to optimize the properties of Hevea rubber or synthetic rubbers. These modifications will be adapted to the properties of TKS rubber. This task could only be performed when there was enough material available.
Finally several prototype car tyres, made with the natural rubber from TKS, were produced and tested indoor and outdoor (snow, wet) and showed to be comparable to the reference.
The polymer received from WP5 has been tested on purity. Purity was always lower as compared to regular natural rubber.
Several analytical techniques have been used to find out the composition of these impurities.
• Extraction in THF, acetone and ETA
• Low heating of TGA combined with Pyrolysis GC-MS at TGA temperature with high mass loss
No other components are found as in regular NR only in higher quantities. A test with liquid isoprene (low molecular weight shows a TGA curve which is comparable to regular natural rubber; no extra weight loss in the temperature range 20-300oC. So it seems to be that the impurities as seen in TGA are not caused by low molecular weight NR.
In Natural dandelion the amount of impurities is higher as in natural rubber from Hevea brasiliensis. These higher content impurities might have effect on mixing of the compound. For this reason mixing experiments have been done to get indication of mixing behaviour of compounds with a high amount of Natural rubber. These mixing experiments were done on Brabender Plasticorder 50 and 350 cc. Before these experiments could be performed mixing cycles has to be developed for the se miniature mixers. The properties of the compound with Natural rubber from dandelion are reduced in comparison to the reference. This probably caused by the higher content of the impurities. These impurities will probably lead to lower shear forces and these low shear forces in the miniature mixers, lead to significant lower dispersion of carbon black in the polymer matrix
The results found with the 50 and 350 cc mixers were comparable.
Bicycle tyres
For the manufacturing of the PCR prototypes compound have to be mixed. Due to limited quantity of NR dandelion available the compounds were mixed at a pilot plant external Apollo. The reference was the shoulder tread compound for the Vredestein Fortezza (25phr NR). In the experimental variant all the NR was replaced by the NR dandelion.
The following observations could be made after testing:
• Equal tensile strength, elongation at break
• High hardness,
• Equal hysteresis (tan delta 70oC = indicator rolling resistance)
• Good dispersion
Prototype tyres have been produced for testing purposes and demonstration projects.
Test results
In an independent laboratory the tires have been test on wet grip and rolling resistance. The following results were found for Dandelion rubber tyres:
• RR better as reference 4-5%
• Wet grip better (+6%) to worse (-4%) dependent on the inflation pressure
Test were done by Tyres Laboratory Wheel Energy Oy (Finland)
Passenger car tyres
For the manufacturing of the PCR prototypes compound have to be mixed. Due to limited quantity of NR dandelion available the compounds were mixed at a pilot plant in Germany (20 liter intermeshing mixer). The reference was the winter tread compound for The winter H product line (13phr NR). In the experimental variant all the NR was replaced by the NR dandelion.
The results of the compound with NR dandelion were comparable to the reference.
195/65 R 15 91H SNOWTRAC 5 Tyres have been produced with the regular compound and a version with NR dandelion. During manufacturing no differences were observed between the prototypes with regular NR and NR dandelion.
The tyres (reference and NR dandelion version) were tested on indoor and outdoor. Indoor test were performed in the Apollo indoor test center, winter performance at SPHG New Zealand. The wet performance could not be tested within the time frame of the project and are not reported here.
Tyre results of both variants were comparable!
Conclusions
1. Natural rubber from dandelion has a lower purity as from Hevea brasiliensis
2. Compound properties of bicycle tyre formulation with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
3. Compound properties of passenger Car tyre tread formulation with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
4. Performance of bicycle tyre with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
5. Performance of passenger car tyres with natural rubber of dandelion was at comparable level as with NR Hevea brasiliensis
Prototype rubber goods
The initial aim was to produce different General Rubber Goods (GRG) parts to evaluate a variety of mechanical properties:
- Abrasion resistance (Agri roller)
- Dynamic behavior (Bearing)
- Static behaviour (Grout seal)
The smallest real size sample is the Agri support roller. This is a patented hollow support roll which controls the seeding depth behind a tractor and reduces the impact on the soil. It requires flexibility, durability, ozone and UV resistance and some specific processing properties like tack, die swell and green strength for cutting.
The product is coreless molded from NR compound and has a closed hollow chamber inside. The rubber is injected with air during curing. The steel disk mounted inside the roller (as a rim) will make the roller airtight.
We have chosen this product due to the application (agricultural) and the easiness to convince the market to use TKS rubber for this application.
Starting point is to replace to surface of the roller with TKS rubber compound in which we’ve replaced 100% of the NR (not a blend) with TKS NR. The benchmark NR is a standard TSR 10 50-80 Moony grade from Vietnam.
The first step in production is the extrusion of the profile. Due to the fact that we did not have enough compound to fill the 120mm extruder, we’ve decided to use a smaller NR base and add an outer layer of TKS compound on top.
The extruded profile will be cut, heated and spliced without any solutions or tack agents. This critical step in the process is important as lack of initial tack will result in 100% rejected products. The molding is done in a special method (IP) and cannot be disclosed or described in this report.
After curing the roller is tested in a specially designed test rig to measure:
- Wear resistance
- Flexibility
- Degradation (under pressure and temperature)
The roll will be mounted to run against an abrasive resin coating. The roller will be measured under different loads, speed, temperatures and angles to simulate all extremes that could occur in the field. These are long test cycles to simulate years of operation in the field. The effect under extreme conditions can be evaluated by visual inspection as the surface of the roller clearly shows the degradation of natural rubber. The samples made from TKS rubber have been produced in August 2018 and the tests are ongoing. The comparison will be made against similar products made in the same mold/cavity and on the same press.
We expect the first results in November 2018. The report will be a comparison table on the compound, the processing properties and the mechanical properties of the final product.
7. Results on demonstration of the economic viability of the TKS production chain for NR and inulin
Economic analysis of rubber and inulin from TKS
The aim of this economic analysis is three folded, following three approaches and assessment are included:
- revenue based modelling,
- business-economic assessment, and
- socio-economic assessment.
-
Revenue based modelling
Revenue based modelling is a general economic analysis of natural rubber and PEF (Polyethylene
furanoate) from Rubber dandelion following the methodology presented in deliverable 7.1 as well.
With this assessment putative framework conditions for the future realization of this new
valorization chain of these two products from Rubber dandelion are pinpointed. The analysis is
mainly based on data and results gained in the DRIVE4EU project, EU-PEARLS, literature and general
information, which were used to calculate some general economic indicators.
Business-economics
Business-economics includes cost calculation of production of Rubber dandelion and by-products in
the DRIVE4EU system. DRIVE4EU system includes 4 process steps (cultivation & harvest, transport,
rubber biorefinery and PEF biorefinery) and technical and economic input data has been provided by
project partners or literature review. Results are given as yearly costs or specific costs related to total
amount of products (rubber and PEF). Cost calculation allows identifying the main impact factors on the production costs. Based on the identification of main impact factors changes to be expected in
the future (targets for e.g. yield, rubber content, decrease in cultivation work) are used for sensitivity
analysis. Results of sensitivity analysis are interpreted to make suggestions for improvements in the
DRIVE4EU system. Based on prices for reference (conventional) products and the production data of dandelion rubber and PEF revenues are calculated to show the economic competitiveness of the DRIVE4EU products now and in the future.
Socio-economics
The socio-economic assessment serves to analyse potential impacts of newly introduced, EU-located
Rubber dandelion production chains on the EU economy. The analysis focuses on the potential value
added generated by these production chains in different economic sectors in the EU as well as
abroad. Major questions are thus, which magnitude of value added could be achieved, which share
of this value added remains in the EU and on which sectors of the economy it may have the most
important impact. In order to address the competitiveness with alternative crops, a brief comparison
with the value generation of conventional crops is undertaken.
The key findings of the general economic analysis for the Rubber dandelion value chain to produce
natural rubber and PEF are:
- Currently there is little reliable information available for the future commercial production of
natural rubber and PEF from Rubber dandelion.
- There are no estimations available for the main cost components along the processes of the
whole value chain available. With the calculation tool for the general economic analysis, using
the assumption, the total production costs for natural rubber and PEF are assumed to be lower
than the total revenues from these products.
- The general economic analysis was based on the following aspects
o Consideration of two possible future business cases in “10 years” and “25 years” with
▪ Rubber dandelion yield 40 – 60 t/(ha*a)
▪ natural rubber yield 0.9 – 2.0 t/(ha*a) and
▪ PEF yield 1.8 – 4.9 t/(ha*a).
o The whole value chain from Rubber dandelion cultivation to natural rubber and PEF
under consideration of the valorization of process residues for animal feed includes
the following 7 main processes:
▪ Rubber dandelion cultivation and harvest
▪ Rubber dandelion transport
▪ Rubber dandelion (drying &) storage
▪ Biorefinery (including processing of inulin to PEF)
▪ Feed production from roots, leaves and pulp
o A “Cost calculation tool” is developed to estimate possible cost distribution along the
whole value chain for Rubber dandelion. The starting point of this cost calculation is
the estimation of the possible revenues on the market of natural rubber, PEF and
animal feed from Rubber dandelion biorefining.
o The main inputs in the tool are: technical data, revenue data from the market,
characteristics of the cases, assumptions and estimations.
Main changes to DRIVE4EU today are:
- Annual costs:
Total costs decrease from 5,752 to 909 Mio. €/a. Costs for cultivation & harvest decrease
significantly due to the future changes/assumptions and this effects significantly on the total
costs. Percentage of cultivation and harvest decreases from 94 % to 64 %.
- Specific costs:
Also specific costs are lowered from range 14 to 22 to range 2.2 – 3.3 €/t tot prod. For the
specific costs the yield of fresh roots and the rubber content are the major influences that
results in this particularly high cost reduction (about 85 %).
- Cultivation & harvest:
Main cost factors are agricultural land rent and agricultural machinery rent (together 72 %).
Plant protective agent holds a percentage of 11 %.
- Rubber Biorefinery:
The energy costs (heat and electricity show together 51 %) have the major influence. Then
followed by the investment costs (annuity and insurance&maintenance show together 48 %).
- PEF Biorefinery:
The investment costs (annuity and insurance&maintenance show together 41 %) have the
major influence. Then followed by energy costs for heat with about 37 %.
Conclusions
Following conclusions can be drawn from the results of cost calculation of DRIVE4EU system:
- DRIVE4EU system today is not economically viable because of
o especially high costs in process step cultivation and harvest,
o low yield of fresh roots and
o low rubber content of the roots.
- Costs of cultivation and harvest are mainly determined by
o costs for agricultural land and
o costs for agricultural machinery
o followed by costs for plant protective agents.
- Further developments in the process step cultivation and harvest are necessary:
o increasing the yield of fresh roots (today 6.6 t/ha; Future1: 40 t/ha; Future2: 59 t/ha)
and
o increasing the rubber content of the roots (from 10 % up to 15 % on DM).
o reduction of costs for agricultural land, agricultural machinery and plant protective agent.
- Main percentage of cost in Rubber biorefinery:
o energy (electricity 31 %, heat from gas 24 %; together 55 %)
o investment costs (annuity 30 %, insurance and maintenance 14 %; together 44 %).
- Main percentage of cost in PEF biorefinery:
o energy (heat from gas 38 %)
o investment costs (annuity 26 %, insurance and maintenance 13 %, together 39 %)
o auxiliary materials (sulfuric acid 1 %, methanol 1 %, ethylene glycol 17 %, acetic acid
1 %; together 20 %).
- Further developments in the process step Rubber and PEF biorefinery are necessary:
o improvement of production efficiency to reduce the costs for energy and auxiliary
materials
o reduction of investment costs
- The analysis of future improvements showed, that dandelion rubber and PEF from DRIVE4EU
system can become economical competitive if the assumed changes/improvements, e.g.
higher yield, higher rubber content, lower fertilizer demand, lower electricity demand, will
actually occur in the future (10 to 25 years).
Socio-economics analysis
The socio-economic assessment serves to analyse potential impacts of newly introduced, EU-located
dandelion production chains on the EU economy. For the production of natural rubber from Rubber
dandelion, this would result in a replacement of natural rubber imports from Asia. For the PEF part of
the production the replaced imports are less obvious as part of the PET production industry is already
located in the EU while a share of PET is imported. Thus, whether raw material (e.g. crude oil) or PET
imports are replaced depends on the specific case and/or on market dynamics. The analysis focuses
on the potential value added in Euros per year generated by these production chains in different
economic sectors in the EU as well as abroad. Major questions are: Which magnitude of value added
could be achieved? Which share of this value added remains in the EU? On which sectors of the
economy may it have the most important impact? In order to address the competitiveness with
alternative crops, a brief comparison with the value generation of conventional crops is undertaken.
The analysis suggests that, even in the 50-50 scenario, the agricultural sector would clearly benefit
most from the introduction of EU based dandelion value chains. This is primarily due to the fact that
the “auto supply” of the agricultural sector is higher than in the chemical industry; while approx. 48%
of inputs to the EU based agriculture stem from agriculture itself, in the chemical industry this share
is 32%. As stated above, standard splits (multipliers) between the input sectors where used. It is likely
that the high input from agriculture to the agricultural sectors is to some extent caused by the
production of feed for animal breeding which does not apply to our case. The use of standard
multipliers can thus only provide a rough idea on value added generation in the EU. A deeper analysis
including value chain data (a “vector”) specifically developed for dandelion products would help to
produce more reliable results. For this purpose, however, more data on the actual production chain
would be required which so far is not available.
The analysis suggests that the major share of the generated value added remains in the EU. With a
replacement of the total import of natural rubber, a value added in the EU agricultural sector of
about 1.2 billion or 1.6 billion EUR in the two scenarios respectively would be generated. Given that
the total value added in this sector in 2014 was 170,690 million EUR according to the WIOT
(exchange rate of 2014), this would correspond to 0.70% or 0.94% respectively of the sector’s value
added. The effects of a potential replacement of other agricultural crops would require a much
deeper analysis, involving agricultural and trade models. In the chemical industry the EU value added
would amount to 850 million or 540 million EUR (50-50; 70-30 split). Based on a total 2014 value
added of 130.168 million EUR, 0.65% or 0.41% of the sector’s value added could be generated. Also
here, potential replacement effects, e.g. due to capacity constraints in the biorefinery sectors, are
not considered. On the other hand, e.g. crop rotations potentially leading to additional proceeds,
were not considered. The generated values are thus to be seen as rough estimations. Provided that
the analysis focuses on two specific products only, the orders of magnitude can however be seen as a
fair share of the existing sectoral activities.
At least for rubber, the analysed value added generation can be assumed to be additional to, rather
than displacing, existing value added of the alternative supply chains. Rubber is currently fully
imported, mostly from Asia. For PEF, the situation differs as there is a significant oil refining industry
in Europe, partly covering current demand of PET. Therefore, a certain share of the value added from
the PEF value chain may not be additional to current European value added.
Survey of economic viability of rubber and inulin from TKS
The aim of this research was to provide information on reasons for favouring or disfavouring rubber and inulin from Rubber dandelion compared to conventional rubber and inulin.
A SWOT (strengths, weaknesses, opportunities, threats) analysis of the DRIVE4EU process is described. The whole project team provided therefore information on:
• Reasons for favouring rubber, inulin and fructose from Rubber dandelion – this is covered mainly by the collection of the strengths and
• Reasons for disfavouring rubber, inulin and fructose from Rubber dandelion – mainly covered with the collecting input of weaknesses
• Technical and non-technical barriers – covered mainly from the collection of threats, and
• Technical and non-technical boosters – covered mainly by the inputs for opportunities
Furthermore we described bottlenecks of the DRIVE4EU process during the project and after the project.
Technical minimum requirements/standards for rubber and inulin (for using it for specific products) are described here. This gives information on the usability of rubber and inulin from Rubber dandelion compared to conventional rubber and inulin. Another part of this deliverable deals with the integration in existing infrastructure.
The biggest strength of DRIVE4EU is the local production of natural rubber, which will be offered by the European production chain developed within the project. Another strength that should be considered is the production of an alternative source for natural rubber and furthermore as well the reduction of the dependency on natural rubber from South-East Asia. A good quality rubber with high molecular weight is expected, and the biorefining as a combination of existing processes is most important for the DRIVE4EU consortium, given that the partners have a wide experience and technology background knowledge in their special field. The upscaling of the processes seems to be simple and easy to handle.
The dandelion would be an annual crop, i.e. the crop will be annually harvesting, in comparison to the rubber tree for conventional natural rubber production, which need 7 years to harvest the first time natural rubber from the tree. A further strength is the availability of inulin in the root next to the natural rubber, so DRIVE4EU is developing a production chain for a bi-product crop for natural rubber and inulin.
Further strengths with votes are: new discoveries for science, cultivation in Europe demonstrated, further improvements possible e.g. rubber content, we have a promising process piloted, no allergic reaction by using natural rubber dandelion, dandelion can be processed for several products, good partners for the whole supply chain, less environmental impact expected, and research of very important alternative source of natural rubber (NR).
Conclusions survey of economic viability of rubber and inulin from TKS
A SWOT Analysis was performed to evaluate strengths, weaknesses, opportunities, threats of the DRIVE4EU process. In this deliverable the methodology of the SWOT analysis is presented, as well as the approach chosen in DRIVE4EU explained and the results of the SWOT analysis in DRIVE4EU. A summary provides information of the most important SWOTs ranked by all project partners.
Economic bottlenecks during the project phase were evaluated, further research and development is needed to reach marketable products, but within all process steps and so the whole value chain was successfully further developed. Needs for further developments are e.g. reach higher natural rubber yield per hectare, quality und purity of natural rubber from Rubber dandelion. Further prototypes from rubber dandelion, next to the high performance bicycle tyres, will be produced in the next months; therefore in relation to a successful production of prototypes more information can be prepared at the end of the project.
With further research and development in different parts of the DRIVE4EU value chain the costs can be lowered and the process can be more and more economic viable.
Market aspects, legislation and regulatory aspects concerning rubber and inulin from TKS
The economic analysis and the life cycle assessment (LCA) in work package 7 is a horizontal
activity of the project DRIVE4EU. On one hand the economic and environmental analyses and assessment should assist the other WPs in the development of most attractive technical solutions and to set up possible integrated valorization chains from TKS cultivation to the final product portfolio made from TKS, e.g. rubber, inulin, chemicals, energy carrier. On the other hand the economic and environmental analyses should set the framework of conditions under which a future commercial cultivation and use of TKS might be possible and the assessment should identify the key factors to be successful on the market in future.
The aim was to provide information on the market of rubber and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET; as a product based on inulin) based on world, European and Kazakh data. Information on production volumes, main producing countries, EU imports, EU exports, prices is summarized. Furthermore this analysis provides information on the regulatory aspects and information on legislation and subsidies.
In this part information on the market of natural rubber (NR) and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET) based on world, European and Kazakh data is provided. Market aspects like production volumes, main producing countries, EU imports, EU exports in relation to natural rubber, tyres, general rubber goods, inulin and PET are summarized.
The world natural rubber market rises to a total of 12.6 million tons in 2016. The six largest producing countries of natural rubber were Thailand, Indonesia, Vietnam, China, India and Malaysia. Not all of these countries are net exporters of NR, e.g. China and India are net importers of NR.
Currently natural rubber is not produced in Europe. Therefore the EU is totally dependent on imports from the natural rubber production countries. In 2016 the EU imported about 1.2 million tons of natural rubber. 34% of this amount came from Indonesia, 18% originated from Thailand and further 16% came from Cote d’Ivoire. The consumption of natural rubber in the EU is mainly driven by the tyre industry which amounts to 76% of the total demand in 2016. The residual 24% in 2016 belong to the general rubber goods (GRG) sector. Tyres market grew in the last five years (2011 – 2016) at a rate of 2.5% per year and is predict to grow further 2.9% per year between 2016 and 2021. GRG consumption will also grow 2.9% per year until 2021.
Due to the fact that Rubber dandelion is a non-food crop, it is maybe not possible to use the inulin from the Rubber root to use inulin for nutrition purposes. Another aspect is the small market volume of the inulin market. Bringing huge amounts of inulin into the market would affect the inulin market
significantly. For this reasons the PET market could be more relevant for Rubber dandelion, using the inulin as a resource to produce PEF (Polyethylene furanoate) as a substitute for PET.
Conclusions market aspects, legislation and regulatory aspects concerning rubber and inulin from TKS
In this research part information on the market of natural rubber (NR) and rubber products (tyres, general rubber goods), inulin and Polyethylene terephthalate (PET) based on world, European and Kazakh data was provided. Market aspects like production volumes, main producing countries, EU
imports, EU exports in relation to natural rubber, tyres, general rubber goods, inulin and PET are summarized.
The world natural rubber market rises to a total of 12.6 million tons in 2016. The six largest producing countries of natural rubber were Thailand, Indonesia, Vietnam, China, India and Malaysia. Not all of these countries are net exporters of NR, e.g. China and India are net importers of NR.
Currently natural rubber is not produced in Europe. Therefore the EU is totally dependent on imports from the natural rubber production countries. In 2016 the EU imported about 1.2 million tons of natural rubber. 34% of this amount came from Indonesia, 18% originated from Thailand and further
16% came from Cote d’Ivoire. The consumption of natural rubber in the EU is mainly driven by the tyre industry which amounts to 76% of the total demand in 2016. The residual 24% in 2016 belong to the general rubber goods (GRG) sector. Tyres market grew in the last five years (2011 – 2016) at a rate of 2.5% per year and is predict to grow further 2.9% per year between 2016 and 2021. GRG consumption will also grow 2.9% per year until 2021.
Due to the fact that Rubber dandelion is a non-food crop, it is maybe not possible to use the inulin from the Rubber root to use inulin for nutrition purposes. Another aspect is the small market volume of the inulin market. Bringing huge amounts of inulin into the market would affect the inulin market significantly. For this reasons the PET market could be more relevant for Rubber dandelion, using the inulin as a resource to produce PEF (Polyethylene furanoate) as a substitute for PET.
The global PET production in 2014 amounted to some 41.6 million tons, and it is forecasted that by 2020 its production will be approximately 73.4 million tons. With more than 35% in 2015 beverages hold the highest market share of PET. In 2016, some 485 billion PET bottles were produced worldwide, and it is forecasted that in 2021, some 583.3 billion of these plastic bottles will be produced. The total European plastics converter (EU28+NO/CH) demand of PET lies at approx. 3.6 million tons in 2016. PET price of bottle grade fee delivered PET lies at around €1,115/tonne FD (free delivered) in Europe at the end of August 2017 which was then exceeded in September 2017 to reach €1,130/tonne FD Europe.
Over all the process steps in the DRIVE4EU value chain and for the products different regulations or legislative issues (e.g. Nagoya Protocol, Plant variety property rights, REACH) has to be considered and clarified before a commercialisation.
Working in the field of alternative NR sources, DRIVE4EU contributes to the sustainability of NR. Furthermore DRIVE4EU offers the possibility to become less dependent on the imports of NR.
Environmental aspects of rubber and inulin from TKS
The environmental assessment was performed to identify, quantify and assess the most important environmental impacts and benefits of the production of rubber and PEF from inulin from Rubber dandelion, based on LCA. The environmental effects are analyzed for each process in the value chain (cultivation, transport, and conversion) and in comparison to the processes of conventional natural rubber from rubber trees and PET based on fossil resources.
The approach chosen included the following steps:
- Collection and assessment of information on the various technical systems and production processes of natural rubber and PEF/PET from Rubber dandelion and from conventional sources - from raw material extraction and cultivation to final products
- Definition and description of LCA system boundaries and elements of DRIVE4EU system and reference systems
- Performing LCA for complete DRIVE4EU value chain
- Assessment of the possible range of the most important environmental effects from rubber and PEF from inulin from the DRIVE4EU system as well as from conventional production
- Drawing of the main conclusions and identification of further R&D issues
The objective of this Environmental impact analysis was to identify, quantify and assess the most important environmental impacts and benefits of natural rubber and PEF production from Rubber dandelion (Taraxacum koksaghyz, TKS), based on life cycle analysis. The environmental effects were reported for each step in the value chain (cultivation and harvest, transport, biorefinery – divided in Rubber refinery and PEF refinery) and in comparison to the processes of conventional natural rubber and PET production.
The assessment of the DRIVE4EU system includes the comparison to a reference system with the substituted conventional products. The reference system provides the same services and products as the DRIVE4EU system with conventional products. All process steps of the value chain are included
for the reference system and for the DRIVE4EU system. For natural rubber of Hevea tree an LCA was performed to analyses the environmental impacts of natural rubber from Hevea tree based on literature data.
In the environmental assessment 24 concepts are included. Eight cultivation concepts varying following characteristics can be chosen: country (Belgium and The Netherlands or KZ Kazakhstan), planting method (sowing or planting), density of plants (low or high), and irrigation (yes or no). For the
processing of the Rubber dandelion roots in biorefineries three possible first commercial concepts are considered defined by the rubber production capacity of 5,000 t per year, 12,000 t per year, or 120,000 t per year.
The LCA of the DRIVE4EU system shows that due to the current state of technology the environmental effects of the DRIVE4EU system are higher than for the conventional reference system. The main influencing factors of the environmental effects are the cultivation and harvest process step especially fertilizer, plant protective agents and diesel. The share of cultivation and harvest lies between 75% and 90% (concepts with planting show higher GHG emissions than concepts with sowing) of the total GHG emission. Comparing to natural rubber from Hevea tree the cultivation and harvest of Rubber dandelion is completely different; the aim in DRIVE4EU is to have as much mechanical work as possible, harvesting latex from Hevea trees results in a lot of manual work.
A sensitivity analysis based on integration of LUC, different energy sources and for future improvements was undertaken. LUC has a significant effect on the greenhouse gas emissions and higher the GHG emissions significantly. Including LUC the cultivation and harvest process step shows
a share of more than 90% of the total GHG emissions. The GHG emissions of the base concept B&NL, sowing, high, y, 120kt without LUC can be reduced by applying renewable energy resources by 19%. In the future 1 the GHG emissions can be reduced by 57%, and in the future 2 by 65%.
The analysis of future improvements showed, that the environmental effects of the DRIVE4EU system could be reduced with possible future improvements. Results of “acidification” and “ozone creation” of the future 2 improvements are in the same range as the results of the conventional
reference system. Following future improvements are assumed, e.g. higher yield, higher rubber content, less fertilizer and plant protective use, lower energy demand in refinery.
Potential Impact:
Potential Impact
One goal of the project was to link key stakeholders in the production chain processes with project news and results. As a second effect, disseminating DRIVE4EU’s goals, intermediate and final results was also an important way to attract partners in EU and worldwide. The dissemination of the project results was essential in general to ensure the international visibility of the project. The concrete actions to achieve the highest degree of dissemination and exploitation of the DRIVE4EU results were the following:
✓ Setting up a website which made sure that users return to the website at regular intervals combined with the development of promotional materials (leaflets, press releases, special reports) which were spread through Europe and which invited interesting partners to contact the consortium or visit the website. The website incorporated a “public”, and an “internal” area where partners were able to share documents etc.
✓ Presentations of the project’s objectives and results during events, forums and conferences. DRIVE4EU was a demonstration project, and therefore all partners tried to present their results at conferences held outside of the project.
✓ Publication of project results in scientific journals, industry oriented journals but also in consumer focused magazines with a large distribution where information about the DRIVE4EU results reached the general public.
✓ Participation and organization of workshops on selected topics bringing together a scientific audience (along with the industry representatives) discussing about the outcomes of the project and future directions of the research activities.
✓ Production and distribution of promotional material of the project’s results, progress and potential benefits - e.g. leaflet, articles, press releases etc., but also the production of promoting materials like rubbers with a printed DRIVE4EU logo or a demonstration box including dissemination material.
✓ Scientific publications and presentations in international workshops and conferences that diffused the R&D results to stakeholders and companies. This included also articles in special magazines (e.g. magazines for the farming industry and tyre fabricants).
More detailed information on the communication and dissemination activities can be found in DRIVE4EU deliverable D8.3 Continuous dissemination and exploitation.
In order to ensure the application of a successful dissemination that diffused information but also contributed to the recognition of the project’s website and other project deliverables, at the project start, a strategy for the implementation of dissemination actions has been prepared and the main dissemination means were defined. The main 3 dissemination lines were:
1. Electronic/Digital dissemination tools: Project website, e-newsletter, e-publications, e-press releases, etc.
2. Hard copy dissemination tools: Project leaflet and posters
3. Individual dissemination tools: Project presentations, oral dissemination at conferences and workshops etc., networking with related projects and platforms, combined course with lectures and field training, etc.
Dissemination materials and activities:
• Logo
An important action in order to establish the project’s identity and to support “brand recognition” was to design a project logo, which is associated and included in all documentation (paper or electronic) and publicity material relating to the project. The identity of the project is guaranteed by the project logo.
• Website
The project website was an important and versatile dissemination tool. The website was continuously developed for disseminating project results, for providing information related to the project and the partners and for the communication among all interested parties. It should be noted that the website served as an interaction point among parties interested in project results and also as the basic point for providing DRIVE4EU related information to all external parties. Indeed, the project web-communication platform was a constant node aiming not only to present and disseminate the project’s results but also to be a referenced site containing useful disseminating material, as well as useful links related to the field of the project. The website was a dynamic tool with ongoing updates and changes over time. The purpose of the project website was to provide access to project results at two levels: one public and one private (i.e. password – protected) for project partners (Member Area) respectively. The website’s address is the following: www.drive4eu.eu.
The website will be available approx. one year after the project ends. Documents for downloads and project relevant events can be added on purpose.
• Articles and press releases
Press releases for the project were created by the project partners in order to present the project goals to a larger audience through magazines or e-press. These press releases raised public awareness about the project and the project objectives. Through these press releases information were diffused and thoughts were exchanged regarding the DRIVE4EU project to groups of stakeholders, commercial and industrial players strongly related to the rubber sector but contributed to the reputation building of the project team.
There has been a long list of scientific publications, articles, interviews, presentation and conference visits from all project partners. More information can be found in the tables “list of scientific publications” and “list of dissemination activities”.
• Brochures
A project brochure was produced in English, electronically and in hard copy. It was used to communicate the existence of the project, its partners, aims, objectives, contents and goals. A short project description was prepared for dissemination among stakeholders, such as breeders, processing industry, extraction machinery producers, biorefinery industry, rubber and chemical industry, at conferences and for other interested actors.
A second electronical brochure depicting the final results and outcomes of the project was developed and will be provided online at the project website for downloading. A draft version is available; the final version will be presented at the final stakeholder workshop.
• Newsletter
Newsletters in English were produced providing information on the project development and events. Newsletters were developed and disseminated during the project duration and sent via email to registered users of the website and further contacts. The first issue of the DRIVE4EU newsletter introduced the project, the project’s objectives, the consortium partners, providing contact points to obtain further information. The other newsletters were used to provide updates on project progress, the project’s results, support the project activities and achievements, and encourage participation in forthcoming initiatives and events. These newsletters were electronically distributed and made available on the project website. A last newsletter will be provided online with the final results, this will be made available in October 2018.
• Further dissemination means
Rubbers with printed DRIVE4EU logo as dissemination material were made and provided to all project partners. The rubbers served as promotion material and were spread to stakeholders in different conferences, workshops and events by the project partners.
A “demobox” with jars and information material was developed. With this demobox the whole value chain of DRIVE4EU is visualized. Information about the complete chain from seed to product is presented and can be explained to the broader public easily. Each partner received 2 demoboxes for demonstration purpose. Jars included with samples for:
o Seeds
o Root
o Biorefinery
o Rubber
o Inulin
o Rubber product
o PEF/PET product
A YouTube movie giving information about DRIVE4EU has been produced by DLO-PRI and was put on the DRIVE4EU website at the 1st page as well.
• Workshops, conferences and exhibitions
Large scale conferences of umbrella organizations in the rubber industry were organized in many different countries and at a very high frequency. In many of these, the DRIVE4EU partners were already involved. It was therefore not the intention to add to this number but to make use of them and/or to create added value. The DRIVE4EU partners have been invited as guest speakers to the conferences by sending in highly qualitative papers.
DRIVE4EU partners participated to several conferences and workshops with presentations and poster sessions. More information can be found in the tables “list of scientific publications” and “list of dissemination activities”.
Furthermore DRIVE4EU was presented at following conferences and exhibitions:
DRIVE4EU was presented at the EUBCE 2017 – 25th European Biomass Conference and Exhibition in Stockholm in June 2017. Therefor a project presentation area (booth) was rented, and the whole week DRIVE4EU was presented. Stakeholders had the possibility to get information on DRIVE4EU and discuss the whole value chain. Dissemination material from DRIVE4EU was spread to the audience.
A prototype of the Fortezza Flower Power was presented at the Eurobike exhibition in Friedrichshafen, Germany, August 30th to September 2nd 2017 (http://www.eurobike-show.de/ and http://www.eurobike-show.de/eb-de/news/1-350-erwartete-Bike-Teilnehmer-aus-aller-Welt.php Figure 14). Dissemination material from DRIVE4EU was spread to the audience. Press releases were made to promote the production and presentation of the prototype.
At the Bioeconomy Conference Bratislava (BBEC 2016), Slovakia a dandelion car tyre from the previous project EU-Pearls (Figure 19) and the project DRIVE4EU was presented on the 17th of October 2016 (http://www.drive4eu.eu/index.php?cmd=s&id=270&PHPSESSID=8nbrui3s5t3bp2ri5lto922p52). For this conference the leaflet was actualized and printed. The DRIVE4EU leaflets and DRIVE4EU erasers were spread around the participants and gained high attention.
A small exhibition area at the office of the Landesrätin für Wirtschaft, Tourismus, Europa, Wissenschaft und Forschung MMag.a Barbara Eibinger-Miedl (Styria, Austria) was prepared. DRIVE4EU was exhibited from January until end of June 2018.
• Joint internal training workshop in Kazakhstan
To disseminate the existing knowledge on main aspects of T. koksaghyz research, and in order to get access of the Kazakh colleagues to main methods of TKS exploration, the organization of “Joint internal training workshops” for the different target groups like members of the team of the Kazakh partner, breeders and rubber industry, farmers, was foreseen. This enabled a European outreach of the project and provided a good chance for dissemination the project into different regions outside the EU. The main objectives of the training workshops were to transfer the knowledge and latest research achievements and practical experiences on the background knowledge and preliminary results. Training sessions in Kazakhstan were hosted several times over the whole project duration. Joint internal training and workshops on the T. koksaghyz issues (recognition, conservation, population dynamics, related and similar species, ecology, monitoruing) were organized for target groups, such as farmers, local government officials and agricultural researchers in Almaty and the Raiymbek district of Almaty region, Kazakhstan.
The courses took place in Almaty, Kazakhstan, and at the sites with TKS present. Lectures were held on May 28 and May 29, 2014, and the field training from May 30 to June 5, 2014, the latter in the Kegen Region, SE Kazakhstan. On September 8,2017, a training for about 30 farmers was carried out within the “Field’ Day” organized by the government of Almaty region in the field of the TKS agronomy in Turgen village Almaty region, Kazakhstan.
• Final exploitation workshops
Two workshops were organized to exploit the DRIVE4EU results. One happened in Rusthoeve, The Netherlands, with the aim to provide information to farmers interested in Rubber dandelion growing. The other one happens after the project, to inform stakeholders on the outcome of the DRIVE4EU.
Date Theme Location
7th June 2018 Stakeholders meeting Rusthoeve, The Netherlands
19th October 2018 Final stakeholder workshop KeyGene, Wageningen, The Netherlands
Stakeholders meeting at Rusthoeve
The stakeholder meeting “Dandelion, the cultivation of the future” at Rusthoeve, The Netherlands, at June 7, 2018, 14:00 – 17:00 was especially developed for farmers interested in growing Rubber dandelion. The production of cultivation of Rubber dandelion was presented to farmers.
The program was the following
Walk-in with coffee and tea
Welcome to the Rusthoeve Trial Farm, by Charlotte van Sluijs, Rusthoeve
DRIVE4EU in a nutshell, by Ingrid van der Meer, Wageningen UR
The cultivation of dandelion, by Hilde Muylle of ILVO Institute for Agricultural, Food, and Fisheries Research
The breeding of dandelion, by Rolf Mank of KeyGene
During the project lots of questions were recieved by farmers who are looking for a new crop to grow. During the meeting Ingrid van der Meer and Rolf Mank gave a presentation about the history of the project. Hilde Muylle followed with a presentation about the challenges of cultivation of the Rubber dandelion. The conclusion of the meeting was, that there will be a lot of chances but still more questions to answer.
Final stakeholder workshop
The final stakeholder workshop will happen at October 19, 2018. This one day event will be at the KeyGene location in Wageningen, The Netherlands.
The meeting is open for registration from August and a maximum of 140 participants can visit. Besides general presentations and pitches from some of the work package leaders there will be several stalls / stands. So each partner can present their work and results. This will allow informal contact between partners & stakeholders. The registration is available under following link: https://www.eventbrite.nl/e/drive4eu-final-stakeholder-workshop-tickets-49083667571.
Currently the following agenda is scheduled:
10.00 Registration / welcome KeyGene / welcome DRIVE4EU
10.30 Start program
About DRIVE4EU - Ingrid van der Meer - WUR, Coordindator DRIVE4EU
An historical perspective on Rubber dandelion - Peter van Dijk - KeyGene
Short pitches of relevant WP leaders informing on most relevant results:
Breeding Dandelion and analysis of gene flow - WP 2/4, Rolf Mank - KeyGene
Agronomy, harvest and storage - WP3, Hilde Muylle - ILVO
Biorefinery and product uses - WP5/6, Frans Kappen - WUR
Economic analysis and LCA - WP7, Maria Hingsamer - Joanneum Research
12.30 Lunch around market place – each partner presents its contribution, expertise and know-how
14.00 Closing presentation by Fazilet Cinaralp - Secretary General ETRMA
15.00 Drink (& Bites)
• Patent
A patent (DE102016115 894.1) is pending on a new biorefinery design of rubber and inulin extraction. Therefore the first recherché report was received and based on that some details have been clarified and modified according to that report.
Most relevant results and lessons learned:
As a result of the project, the vast majority of the foreground generated during the project corresponds to general advancements in knowledge in the form of lessons learned and improved know-how leading to cost effective and resource efficient processes. As mentioned before for biorefining of rubber and inulin based on Rubber dandelion a patent is pending.
Furthermore results for further exploitation are available in the form of scientific research that can be either be published or may serve as input to new R&D projects. For the DRIVE4EU industrial partners the project has served as an excellent opportunity to test and demonstrate their technologies in order to obtain more reliable and scalable industrial solutions for Rubber dandelion processing.
The following points summarize the most relevant results and lessons learned; that can be extracted from the DRIVE4EU project:
New dandelion hybrids with optimized characteristics
DRIVE4EU developed Rubber dandelions with a higher rubber yield. Therefore a sophisticated system of crossing and selection techniques was used. Several novel hybrid strains were evaluated as most promising ones with the potential of a relatively high rubber producer (up to 18% rubber on dry weight). Stable hybrid lines have the attributes desirable for a rubber plant: high biomass, high percentage of rubber in the roots. Some have additional attributes such as; agamospermy, permanent hybridity and polyploidy of the alloploidy type, no need for pollination. Breeding process is still ongoing to improve the rubber yields even more. A higher production can be achieved by improved agronomy and by breeding bigger plants with more rubber and inulin.
Agronomy
In order to achieve the best agronomical, sustainable and economical production, several trials were conducted to obtain a good opinion on the agronomy of Rubber dandelion in Europe and Kazakhstan. The consecutive steps in general root crop production were explored and demonstrated: sowing (bed preparation, densities, sowing date), fertilization, herbicide treatments, harvesting (harvest machines, harvest date) and storage. Different seed bed systems (ridges versus flatbed) were explored. Planting on flat field resulted in high densities and higher yields, but root morphology was more optimal from planting on ridges. Ridges resulted in longer roots, but a lower plant density and a lower yield on a hectare basis. The field germination was improved by priming and pelleting the seeds. Sowing conditions are optimal in late spring or early autumn if sufficient moisture is available. Herbicides, which can be used in the cultivation of Rubber dandelion, are identified. Further, several harvesting technologies were tested to harvest the roots as clean as possible, with minimized breaks in the roots and minimal harvest of the leaves.
Information on the interaction between cultivated and wild dandelion, conservation of wild dandelion
Crossing experiments between Taraxacum koksaghyz (TKS) and related dandelion species indicate that hybridization is possible under controlled conditions. To determine whether 66 years after the end of seed production of TKS in the Swedish county of Skåne still traces of TKS were present in the environment and TKS genomic fragments could be detected in dandelion relatives, a detailed large scale population genetic study was performed. This study showed that not a single TKS-specific allele was found. This is consistent with the absence of TKS-specific morphological characteristics at the sampled locations. TKS represents an economic plant, an alternative rubber producer, with a potential of world importance. Conservation of TKS is needed because its natural occurrence is confined to a small geographical range in Kazakhstan, and there are factors with negative impact on TKS, and trends that may influence TKS in future. The currently existing threats that may influence the performance of TKS primarily include the rainwater and spring water deficit after a relatively long period of drought. Another threat is represented by gradually intensified sheep grazing leading to soil degradation and erosion. As regards the expected trends in future include the agriculture intensification, cropland expansion and new irrigation plans. If applied to the TKS region, each of these plans would directly or indirectly threaten the TKS localities. The measures recommended include, primarily, a formal landscape protection (as a Protected Landscape Area) with some activities blocked at and near the TKS localities, with management of TKS sites limited to a sparse horse grazing.
Biorefinery design
A biorefinery process was designed and used to extract natural rubber and inulin from Rubber dandelion. For the biorefinery design of rubber and inulin extraction a patent is pending. Depending on the quality of dandelion roots: the biorefinery process is easy to operate; sand is very bad for the process, leading to abrasion of equipment; lower separation efficiency (loss of rubber); and lower purity of rubber. The biorefinery process is an up-scalable process, low manual labour is needed and the efficiency in rubber recovery is high. Inulin is available in a solution, which has to be processed further. Inulin can be used to produce Polyethylene furanoate (PEF), which could substitute the fossil-based Polyethylene terephthalate (PET).
Prototypes made of dandelion rubber
A first bicycle tyre with natural rubber was produced. This particular series of prototype tyres are made with rubber extracted from Rubber dandelion grown and harvested in The Netherlands. The tyre prototype provides better grip than traditional compounds, which is directly related to a higher concentration of natural resin in this particular variant of natural rubber. The better grip was especially on wet-deck, which is a good property for high quality bike tyres for racing bikes. Furthermore, a set of eight passenger car tyres, 195/65R15 Snowtrac 5, were produced containing natural rubber from Rubber dandelion that have been analyzed and tested for their performance in driving experiments. Compound properties were at a comparable level to Hevea natural rubber and also the tyre results indoor and outdoor (snow, wet) were comparable to the reference. These tests were performed in New-Zealand on snow and ice to analyze performance under stringent conditions. Also prototypes of rubber goods in building and agri industry were developed and tested. And finally dandelion rubber was tested in off road prototypes. Further prototypes of other rubber products are made after ending of the project with the rubber extracted in the last part of harvesting. Further extraction and cleaning of dandelion rubber to improve the purity is necessary mainly for the rubber goods because they need a higher purity percentage compared to the rubber used for car and off-road tyres. The mixing cycle of compound and/or reformulation of recipe to compensate for the initial resin content was made. In comparison to natural rubber from Hevea trees: rheological behaviour is similar but more degradation, some mechanical properties are lower, compression set is significantly higher, ageing properties are comparable but from a much lower starting point, processing is much easier. The wet-deck grip is higher for car and bike tyres made with dandelion rubber.
Economic analysis and life cycle assessment
The methodology of economic and environmental assessment was successfully applied to the DRIVE4EU value chain. The main influencing factors of the economic and environmental effects are the cultivation and harvest process step especially fertilizer, plant protective agents and diesel. The assessment showed that the economic viability and environmental sustainability of the DRIVE4EU system could be reached with future improvements. Following future improvements were assumed: e.g. higher yield, higher rubber content, less fertilizer and plant protective use and lower energy demand in refinery. The knowledge of the methodologies used for the assessment was deepened; these further developed methodologies will be used in future research collaborations.
List of Websites:
http://drive4eu.eu/
Contact details are: Project Coordination
- Dr. Ingrid M. van der Meer
- +31 31 74 81 363
-Ingrid.vanderMeer@wur.nl
Dissemination Leader
-Mag.a Maria Hingsamer
- +43 316 876 1421
-maria.hingsamer@joanneum.at
Furthermore, project logo, diagrams or photographs illustrating and promoting the work of the project (including videos, etc...) as well as the list of all beneficiaries with the corresponding contact names can be submitted without any restriction.