Final Report Summary - COTTONBLEACH (Improved novel eco-friendly bleaching system for cotton using enzyme and ultrasound processes)
Executive summary:
The European Union (EU) textile industry, worth over EUR 119 billion and giving work to more than 1 million people, is a sector in which Small and medium-sized enterprise (SME)s employ 70 % of the workforce in regions where textile plays a vital socioeconomic role. The overall competitiveness of this sector is straining under price competition from outside the EU, especially from the Far East. In addition, European cotton manufacturers are facing a serious competitive threat as cotton loses ground to synthetics on the basis of price, perceived quality and diversity of end-uses.
Global market pressures are compounded by the heavily chemical-dependant nature of the sector, subject to the cost of applying EU environmental legislation. Current bleaching methods use hydrogen peroxide and in much lesser degree, sodium hypochlorite, resulting in fabric damage, formation of toxic by-products and large amounts of water and energy to remove these chemicals.
COTTONBLEACH was born as a new solution for this problem that should improve textile quality while also promotes savings of energy and chemicals by means of the implementation of an innovative and more efficient bleaching process formed by a conjunction of two sequential enzymatic treatments enhanced through the use of ultrasonic techniques that promotes generation of powerful shock waves that cause effective stirring / mixing in the liquid-solid interface, improving homogenisation, solubilisation, mass transport and mass transfer phenomena. The implementation of COTTONBLEACH technology within the conventional process has proved to be capable to provide higher whiteness levels even with lower temperatures and a decrease in chemicals consumption, which provides the basis to reach significant savings in textile industry.
The whole COTTONBLEACH treatment involves a first enzymatic pre-treatment with laccases, enhanced with ultrasonic devices performance, a second enzymatic step with Oxi-MtCDH (an enzyme developed by one member of COTTONBLEACH consortium within the project's life) that results in in-situ hydrogen peroxide production when the optimal conditions for the enzyme are used, and a final bleaching step at lower temperatures improved by ultrasounds energy.
During the 36 months life of COTTONBLEACH project, the consortium has not only carried out numerous Laboratory tests, but also has designed, constructed and validated a final industrial COTTONBLEACH prototype, based on a current machine design which has undergone significant updates to allow implementing the crucial ultrasonic devices. The machine has allowed the consortium to carry out several tests during the lasts months in order to verify the first laboratory results and definitely prove the accomplishment of the technical and scientific objectives.
The COTTONBLEACH consortium comprises Research and technological development (RTD) performers with strong expertise in process ultrasound enhancement and characterisation and development of enzymes, which have been supported by SMEs with expertise in enzyme production and in ultrasound technology. In addition, the consortium has counted also with an SME specialised in textile machinery manufacture, a cotton textile manufacturer / processor end-user and a Spanish textile association, which have conferred the group with the essential know-how and experience to be successful in all its tasks.
Project context and objectives:
The current global economic and financial crisis has severely impacted the textile and clothing industry - predominantly SME-based, with 73 % of the total labour force working in SMEs - with orders and production falling by double digits since October 2008. At the same time this sector is one of the hardest hit by other countries sheltering their local industry from competition.
The sector is still reeling from previous blows: the 2005 abolition of EU textile quotas which has opened the EUR 66 billion value-added European textile market to low-cost Asian producers, and the costs of complying with recently implemented environmental legislation (IPPC and REACH), has an estimated cost of EUR 3.9 billion for the textile industry. In June 2008, the European Council adopted a new reformed EU cotton support scheme, establishing national programs to facilitate cotton industry restructuring in light of the increasing loss of jobs and productivity. In 2007 alone, employment in the sector dropped by 6.4 % or nearly 165 000 employees compared to 2006 for the 27 Member States, one of the highest losses in the last decade.
Consequently, the sector is being forced to minimise operation costs and production losses. The proposed COTTONBLEACH technology was thought as a technological tool to achieve these objectives by reducing fiber damage as well as chemicals and energy consumption, providing a cost effective process to comply with current EU environmental legislation instead of moving cotton finishing jobs to other countries with less strict environmental norms. The SME-AGs behind the project illustrate the need with real examples from their members; company after company moving their bleaching operations to India and China for lack of competitive options in the EU from textile processing companies in compliance with EU environmental standards. Even then, many are uncomfortable with the high health impact of the Asian model and would much prefer to use bleaching technologies with minimal environmental impact. The 'green' nature of COTTONBLEACH ensures that the benefits of this technology will remain in Europe, as Asian textile processors have no environmental concerns to motivate the adoption of green technologies.
Regarding these chemicals used in the abovementioned treatments, the most common bleaching agents employed by the industry are based on sodium hypochlorite (for a limited set of applications) and hydrogen peroxide. Nevertheless, for environmental reasons (possible formation of halogenated organic compounds) the use of chlorine-based components is now limited in Europe to just a few particular cases, associated with knitted fabric and, in some cases, bleaching of yarn when a high degree of whiteness is required. Consequently, H2O2 has gained popularity as a bleaching agent as it is non-yellowing, non-toxic (degradable into water and oxygen), and odourless. In addition, H2O2 does not have the effluent problem that is associated with chlorine bleaching regarding the formation of halogenated compounds. However, such bleaching solutions usually require 40-50 minutes and temperatures of 90 - 100 degrees Celsius to obtain acceptable whiteness values added to the fact that simple solutions of H2O2 are ineffective in bleaching without additives.
Main limitations of existing technologies include:
- Chlorine-based bleaching can cause environmental problems due to the presence of chlorine breakdown products, leading to the formation of AOX and other toxic compounds.
- NaClO bleaching requires special safety measures, increasing the cost of the process.
- Hydrogen peroxide bleaching methods require temperatures close to boiling point to obtain successful whiteness levels and therefore require high energy consumption.
- Traces of hypochlorite and peroxide remain in cotton fabrics and can result in yellowing and damaging fibres, respectively, as well as interfere in dyeing and posterior cotton finishing processes. Therefore, higher amounts of water and energy are needed to remove both from fabrics.
- Extreme pH medium needed both in sodium hypochlorite and hydrogen peroxide bleaching processes produce high environmentally hazardous waste liquors (high BOD and COD levels), requiring expensive water treatments.
Project objectives
As a result of the above issues, the RTDs of the consortium came with an innovative treatment that, within a EU financed Seventh Framework Programme (FP7) project, would end with a pre-competitive prototype that could be further developed that promoted, as the main objective, to obtain a better bleaching process, faster and more efficiently than current peroxide processes.
The general overview of full treatment is shown in the diagram below, which also proves how the additional steps are integrated into the conventional process ones.
The technological and scientific objectives are listed below:
- develop the pre-treatment based on the use of laccase enzymes, cutting the need for H2O2 by 50 % and for rinsing water by 40 %;
- high frequency ultrasound will be tested for first time in this kind of application. The results obtained will be compared with those at low frequencies, comparing the effects on higher radical formation;
- the suitability of pulsed-ultrasound will be tested in order to improve the cost-effectiveness of the system, identifying the proper pulse conditions to achieve a balance between the cost and the bleaching effect. Enhance the bleaching process by ultrasound performance, investigating suitable frequencies (20-600 kHz) and intensities in order to optimise cavitation on an industrial scale;
- develop and find the optimal condition to obtain In-situ H2O2 production by means of glucose oxidase (GOX) which should cover peroxide demand (5.44 g H2O2 / Kg cotton), generating gluconic acid as by-product and thus avoiding the use of chemical stabilisers;
- soften the operational conditions (pH 8-9; temp. 50 degrees Celsius; duration 30 min) reducing energy costs by up to 50 % and minimising fibre damage (also helped by the highly specific enzymes that will affect only non-cellulosic fibres, without damaging the cellulose part in cotton);
- validate with trials all these advantages scaled in a cost-effective pilot plant designed and constructed by the consortium, with optimal integration of the COTTONBLEACH technology, to ensure the proposed 'add-on' system fulfils the objectives;
- obtain an 8% increase over current cotton fabric bleaching levels through classic methods;
- the proposed device, including equipment, installation and maintenance, might have a cost around EUR 60 000.
Project results:
Project objectives were defined in the initial work programme of COTTONBLEACH as Work packages (WP)s and the main tasks were arranged according to the activity and their time requirements. This program might help manage the research and validation work by the partners to assure the fulfilment of the objectives during all project's duration. The SME partners and associations would be involved in the research field, supplying their specific knowledge and experienced know-how, although most part of the innovation must be carried out by the RTD performers.
- WP1 - System specifications
The first stage of the project was considered aiming to provide an overview of cotton manufacturing processes (paying special attention to the bleaching processes), acquire information from the end-users regarding industrials standards from health, safety and manufacturing point of view, legislation and requirements not covered by current technologies.
Moreover, during the first technical meeting of the project, ACATEL (Portuguese finishing textile company, mainly focused on dyeing, mercerising, bleaching, piece dyeing, printing, flocking and finishing of knitted fabrics in rope or garment) and BRAZZOLI (Italian worldwide leading manufacturer in the production of machines for dyeing and finishing of both woven and knitted textiles) shared with the consortium partners their case study with detailed information regarding the production processes that were being carried out in their facilities and technical information about textile machinery.
The studied bleaching processes were two: super white cotton and half bleaching (further dyed), since both cotton treatments represent a big part of their bleaching necessities.
WP2 - Laccase pre-treatment enhanced with ultrasound
During WP2 the influence of laccase pre-treatment in the peroxide bleaching of cotton textiles was evaluated. With the aiming to reduce the amount of hydrogen peroxide consumption in bleaching process, the conditions of enzymatic pre-treatment were optimised for whiteness enhancement.
The first step was to introduce the laccase from Ascomycete Myceliophthora Thermophila, which have proved ability to degrade and oxidise. Various reaction factors were considered to optimise the enzyme pre-treatment for bleaching enhancement such as laccase dosage (0, 1, 4, 6, 10, and 20 U / mL), incubation temperature, and elimination of fabric preparation process. Furthermore, the decrease of hydrogen peroxide consumption was attempted in bleaching process after enzyme pre-treatment. Previously desized and desized / scoured cotton fabrics were incubated in 0.1 M acetate buffer, pH 5, in the presence and absence of laccase enzyme.
After termination of enzyme pretreatment, the fabrics were taken and washed off in warm water for 10 minutes to completely remove the residual enzymes from the surface of fabrics. All the processes of enzyme pre-treatment and bleaching process using hydrogen peroxide were carried out on desized and desized / scoured cotton fabrics.
For each process, the best conditions using ultrasound were set and compared with the results made in conventional equipment. Different ultrasonic powers were studied (30, 60, 90, 120 W) at frequency: 850kHz.
Main results:
a. determination of the most promising source of laccase, namely ascomycete Myceliophthora thermophile;
b. characterisation of the best processing parameters for enzymatic pre-treatment:
b1. the optimum temperature for ensymatic treatment resulted at 50 degrees of Celsius, since the enzyme maintained stable for 1 hour of incubation and lost just 10 % of its activity after 24 h;
b2. the laccase concentration for pre-treatment was optimised (2 U / mL);
b3. the optimum time of incubation was ½ hour;
b4. washing for 10 min. at 50 degrees of Celsius with Lutensol AT25 (1g/L);
b5. 50% of protein adsorption at the moment of pre-treatment on scoured fabrics;
b6. whiteness (W*)= 35 for fabric samples given by ACATEL.
c. Characterisation of the best process conditions of ultrasonic bleaching:
c1. for half-bleaching: 1g / L hydrogen peroxide; 1 g / L sodium hydroxide; 80 degrees of Celsius for 120 min.; 10 min. of washing with tap water (W* equal to 63.5);
c2. for super-white: 8g/L hydrogen peroxide; 4 g/L sodium hydroxide; 80 degrees of Celsius for 1 hour.; 10 min of washing with tap water (W*77.1).
d. determination of the synergistic effect provided by the ultrasounds surrounding the cotton fibres during the bleaching step.
WP3 - Bleaching process characterisation
Within the tasks carried out at WP3, CRIC (RTD) characterised the ultrasonic bleaching enhancement through experimentation at FISA's (SME) facilities, optimising bleaching process under cavitation. Partner FISA is specialist in design, manufacture and sale of automated ultrasound cleaning machines, so they counts with testing laboratories for best cleaning conditions characterisation under ultrasonic fields, equipped with temperature controlled stainless steel vessels, which include piesoelectric and magnetoestrictive transducers.
The extensive experimentation allowed the RTD to identify the most optimal processing parameters to obtain the highest cotton's whiteness. The tested parameters were:
- ultrasounds (two kinds were tested: piesoelectric and magnetoestrictive);
- temperature (70, 90 degrees Celsius);
hydrogen peroxide concentration (2, 4, 8 g / l);
- processing time (30, 60 min).
The final whiteness measurement for each sample that had undergone a different treatment involving a specific combination of parameters was evaluated through a spectrometer, which returns values of Berger's Index, providing reliable information about the cotton's whiteness level and allows doing comparisons between different values. The whiteness increases proportionally to the Berger index.
Main results
a. The calorimetric data allowed evaluating the ultrasonic bleaching enhancement through experimentation, confirming that applying ultrasounds while the bleaching process is being carried out has a positive effect in its efficiency. As it can be observed in the graph below, same raw cotton fabrics, having undergone the same bleaching process with identical operational parameters, resulted in higher whiteness when ultrasonic transducers were working in the vessels.
b. However, there were no significant differences between the results obtained with piesoelectric or magnetoestrictive devices, so it has been not possible to conclude that one kind provides higher whiteness levels than the other.
c. Nevertheless, the results achieved by University of Minho and CRIC during experimentation allowed identifying the piezoelectric technology as the best technique in terms of performance related to costs. Taking into account also power density, and based on the experience cumulated by the experts participating into the project, the power scale-up for the devices was 1 kW.
In addition, further experimentation at FISA's facilities included also the enzymatic pre-treatment before bleaching step, consisting of a 30 minutes process at 50 degrees of Celsius, with ultrasounds and Laccasse concentration of 2 u / ml , since these were the optimal processing conditions, specified by TEM as the conclusion of their laboratory tests. The experimentation within the following bleaching step also allowed obtaining some evidences about how the temperature, processing time and peroxide concentration affected on the final whiteness.
- Comparing the values of WI Berger of all the tests, the whiteness achieved after laccase pre-treatment was significantly higher the obtained under same conditions with conventional bleaching process. Furthermore, it was proved that, even using lower peroxide concentrations, the WI Berger at 90 degrees of Celsius was higher than the maximum achieved during the conventional test.
- The laccase pre-treatment accelerates the bleaching speed, since higher whiteness values were obtained after 30' bleaching process with enzymatic pretreatment than with 60 min conventional process without the first enzymatic step.
- The temperature proved to be the most critical factor to improve the final whiteness. The targeted goal of decreasing the processing temperature till 70 degrees of Celsius had to be reconsidered in future tests carried out in the final pilot plant, since it was not possible to conclude that combining temperature and peroxide reduction would not negatively impact on the whiteness.
WP4 - Peroxide production from desizing waste water
Gras University started performing its work being focused on investigating GOX and its potential within Hydrogen Peroxide production.
Nevertheless, during the project's life, a relatively new highly promising ensyme showed several advantages compared with GOX. Consequently, the interest of the project was modified and the researchers also focused their attention and put higher efforts to compare both and arise with the most promising and suitable Hydrogen Peroxide producer. Advantages linked to CDH are:
(i) its massive production for industrial scale,
(ii) in-situ peroxide production (CDH binds to cotton, producing H2O2 onto the fibre) and,
(iii) being capable to use other monosaccharides as substrate (glucose, cellobiose, lactose, maltose).
Considering these first findings, the following activities, aimed at defining the reaction conditions and treatments for in situ generation of hydrogen peroxide, were carried out during the course of the year:
0. studying the most suitable carbohydrate substrates;
1. production of recombinant Myriococcum Thermophilum MtCDH;
2. study H2O2 production using GOX and Cellobiose Dehydrogenase (CDH);
3. peroxide Production;
4. bleaching process using desizing waters.
A. Studying the most suitable substrate
- GOX requires only glucose as a substrate. However, CDH is able to use other several carbohydrates, especially disaccharides arising from the desizing and scouring processes.
- Different concentrations of carbohydrate substrates (lactose, glucose, maltose, cellobiose) were incubated with CDH, and it was found that the highest concentrations of hydrogen peroxide were produced in the presence of Lactose.
B. Production of recombinant MtCDH
Since the preliminary studies showed many advantages of using CDH instead of GOX, An overnight pre-culture of the Pichia pastoris strain PMTS (carrying the MtCDH gene) was inoculated into 30 L of production stage medium in a 70-L bioreactor, and a total of 700 mg partially purified MtCDH was obtained, which has been used during the project. The final recombinant CDH preparation had a specific activity of 3.5 U mg-1.
In terms of cost, although not commercially available, CDH cost is estimated at around EUR 30/kg lyophilised. However, we expect these costs will be more competitive.
Nine amino acids near the active site were selected for mutation (C291X, N292X, W295X, L324X, T599X, R601X, S699X, N700X and N732X) and libraries with more than 400 clones each have been constructed.
C. Optimising H2O2 production
This task was mainly focused on studying the variables that affects hydrogen peroxide production, doing a higher effort in demonstrating if the presence of gluconic acid, obtained as a b product during the enzymatic production of H2O2, could lead to enhanced stabilisation of hydrogen peroxide acting as the chelating agent substitute.
The activities carried out to characterise the stage of hydrogen peroxide production are:
a. effects of temperature on hydrogen peroxide in the presence of gluconic acid;
b. effect of metals present on the cotton on hydrogen peroxide (in the presence of gluconic acid);
c. comparing the stabilising effect of gluconic acid and dipicolinic acid.
- The effects of the temperature were studied by monitoring during 1 hour the stability of the Hydrogen Peroxide, while it was incubated in 1Mm of gluconic acid. Although there were no significant changes at 50 degrees Celsius, the concentration of hydrogen peroxide at 90 degrees Celsius showed a decomposition more pronounced, so unfortunately, the researchers must assume that, at standard bleaching temperatures, the gluconic acid cannot offer protection to hydrogen peroxide.
- Hydrogen peroxide was incubated during 2 hours in the absence and presence of different metals (cooper, zinc, manganese, calcium) and the hydrogen peroxide concentration was monitored during this period. The amount of hydrogen produced in the absence of the metals was approximately 40 % higher than in the presence of metals.
The metals tends to react with the hydrogen peroxide generating peroxides in the process as well as reacting with acids producing salt and water, so the results of the studies showed how the hydrogen peroxide decreased in the presence of metals directly related to the increase in metal concentration. This effect came from both sides, the peroxide reacts with the metals and the reaction with gluconic acid also shifted the pH, resulting in the destabilisation of hydrogen peroxide.
- The stability of hydrogen peroxide is more pronounced in the presence of sodium silicate as than gluconic acid, but unfortunately, it is also affected by metals, so both gluconic acid and sodium silicate could not protect the hydrogen peroxide decomposition.
Further results
Researchers from University of Gras kept working after the period involved in WP4 and developed a new enzyme called oxyMt-CDH, which can be presented as one of the most important results of COTTONBLEACH Project, and presents a high specificity towards different source of monosaccharide's (100 times more affinity than initial GOX), producing in-situ larger amounts of hydrogen peroxide.
The experimental tests done at CRIC's facilities (WP6 'Industrial validation') were carried out entirely using this new enzyme.
WP5 - Integration and prototype construction
WP5 involved all the work done by the consortium concerning COTTONBLEACH's pilot plant design and construction. The overview of the main results achieved during the previous work allowed describing the best design for the pilot plant, including flow diagrams, CAD files and operational conditions. In addition, the secondary services needed for proper operation were defined at this stage also, as well as the user-friendly software specifications and the essential safety measures.
The final prototype has been constructed, based on a BRAZZOLI finishing machine with a 5 Kg load (concretely INNOLAB HT5) that had to be modified accordingly to COTTONBLEACH innovations requirements, which were studied and defined after gathering all the information from previous work done, and involved the preparation tanks (Laccase solution, CDH solution and bleaching agents), the ultrasonic devices, the side equipment and the control software.
A. Ultrasounds Integration
Ultrasounds interact at two different levels, with concurrent effects. During pretreatment ultrasounds are supposed to boost diffusion rates, while at the bleaching step, are supposed to boost diffusion rates as well as generate radicals able to whitening cotton fibres. For this reason, two different technologies were installed within the equipment: high power and high frequency ultrasonic devices.
(i) High power ultrasounds (HPU)s: 42 piezoelectric transducers (22 KHz) were placed at the main tank bottom, close to the inner basket, where the cotton goods lay. The 50 W transducers were joined by six flanges (3 at each side in parallel) and can be modulated up to 2.1 kW (6 x 7 x 50W).
(ii) High frequency ultrasound (HFU)s): 850 KHs (@ 400 W) Piezoelectric transducers were installed at the recirculation pipe, just before the jet.
B. Preparation Tanks
One tank involves the enzymatic pre-treatment preparation by preparing the laccase solution while the watered solution is heated-up at 50 degrees of Celsius (maximum activity) before filling the housing with the suspension.
Two additional tanks were considered for Hydrogen peroxide production by means of enzymatic reactions. Even though CDH demonstrated better production ratios and flexibility than GOX did, it is in an early stage of development yet, so the prototype was designed to be able to prepare both enzymatic solutions, since GOX has proved to be more robust and commercially available, therefore more competitive from an economic point of view. GOX: the tank reproduces the optimum conditions of temperature, substrate concentration and enzyme concentration, while the system is continuously regenerated and the produced hydrogen peroxide pumped to the system when bleaching.
CDH: The tank prepares the solution (0.05 U / ml), condition temperature (30 degrees Celsius) and desired substrate concentration (between 60 and 100 mg / ml). When the recipe is finished, the content (water + enzymes + substrate) is introduced at the reaction tank, since CDH must bind to cotton to be effective.
C. Side equipment
The prototype as a whole comprises also:
- team generator;
- propane gas installation;
- ultrasonic generators;
- peristaltic pumps to introduce the concentrated solutions and chemicals;
- (Laccase enzyme + Lutensol if necessary, GOX - CDH enzyme, substrate (glucose), bleaching agents).
C. Control system
The elements controlled by this software are:
- BRAZZOLI Machine (reel, pumps, heat exchanger/s, sensors and actuators);
- Steam Boiler (Burner, feed pump, sensors and actuators);
- Side equipment (HPU, HFU, peristaltic pumps, sensors and actuators).
WP6 - Industrial validation
The main goal of this last technical WP was to the study covered the three main innovations of the project, namely laccase pretreatment, ultrasounds enhancement and hydrogen peroxide production; and in depth detail, the parameters studied were water, energy and chemicals consumption, as well as time, temperature and cost.
Potential impact:
The EU textile industry, worth over EUR 119 billion and giving work to more than 1 million people, is a sector in which SMEs employ 70 % of the workforce in regions where textile plays a vital socioeconomic role. The overall competitiveness of this sector is straining under price competition from outside the EU, especially from the Far East. In addition, European cotton manufacturers are facing a serious competitive threat as cotton loses ground to synthetics on the basis of price, perceived quality and diversity of end uses. In June 2008, the European Council adopted the reformed EU cotton support scheme, establishing national restructuring programmes to facilitate cotton industry restructuring and to enhance quality and marketing of the cotton produced.
Global market pressures are compounded by the heavily chemical-dependant nature of the sector, subject to the cost of applying EU environmental legislation. Current bleaching methods use hydrogen peroxide (H2O2) and in much lesser degree, sodium hypochlorite (NaClO, aka bleach), resulting in fabric damage, formation of toxic by-products and large amounts of water and energy to remove these chemicals.
COTTONBLEACH technology will deliver end-user textile AG members with savings reaching 140 000 EUR / year for productions of 1 500 tonnes / yr of fabric (EU average), counting the savings in water, energy and chemicals against the new costs of enzymes and ultrasound. The expected COTTONBLEACH system tag price is of 40 000 EUR for SME-AG associates, a 33 % discount over the full tag price of EUR 60 000. The production cost will be of EUR 28 000, besides an additional fee of EUR 1 000 for the installation and the specification of the equipment. Most end-users have a technical maintenance department making installation costs overheads for them. The costs include the direct and indirect expenses related to staff, investment in machines and manufacturing tools, marketing activities, overheads and other operational activities, representing the 40% of the production costs.
COTTONBLEACH will have a clear economic impact on the production costs associated with water use with savings of EUR 190 000 / year, given the high water demand of the industry. COTTONBLEACH technology will also lower operational temperatures and process duration. Reducing the operating temperature to 40-50 degrees Celsius can cut costs by up to EUR 120 000 / year. Finally, dropping enzyme prices and the cost of ultrasound (EUR 3 / m3 water) ensure the cost-effectiveness of the proposed technology, avoiding the use of H2O2 and stabilisers (EUR 130 000 / annum) and minimising fiber production losses (4 % or EUR 70 000 / annum).
Dissemination activities
The consortium carried out plenty of dissemination activities that had been previously planned within the dissemination actions plan and also a significant amount of additional actions, which involved both publications and events (fairs, seminars, conferences). Among all this activities, also social networking has been encouraged by the creation of Twitter, Facebook and LinkedIn accounts, related to the project.
Exploitation
At the end of the project, the SME-AG / SME partners are still planning to follow the initial business plan, described in section B.3.2 of annex I of the grant agreement. The business plan and the strategies towards exploiting the results have been discussed reiteratively. The consortium has devised an overall plan for the exploitation of Foreground, taking into account that the SME-AGs own all foreground but lack the capacity to exploit it commercially by own efforts. Therefore, they shall reach a commercial agreement with UTC, FISA and BRA, under the following terms:
SME-AGs will grant a manufacturing and commercialisation license to UTC, FISA and BRA for the COTTONBLEACH system. The three companies have reiterated their interest for becoming licensees of the system if real benefits are foreseen.
- In this case, UTC, FISA and BRA will pay royalties to the SME-AGs in exchange of the licensing, concretely 5 % of the gross benefit earn selling the equipment. The royalties percentage will be finally settled when the exploitation takes place. Considering that the target operational cost of EUR 0.16 / Kg cotton has not been yet achieved, the actual percentage of royalties cannot be accurately calculated. Once limitations will be arranged, operational cost will allow the SMEs to calculate their gross profit from the use of COTTONBLEACH and thus would be able to agree on fair and reasonable royalties with the SME-AGs.
- In parallel, the SME-AGs will promote COTTONBLEACH in the textile sector and attract potential customers. On top of the royalties that they receive from UTC, FISA and BRA they will thus gain additional commission-based income for their promotion efforts, calculated as 10% of the gross benefit. Once again, the actual gross benefit needs to be calculated more accurately taking into account the operational cost and therefore the 10 % shall be revised.
- Finally, and with the objective of favouring their associates, the AGs will ensure that UTC, FISA and BRA sell the system to the AG associates at a favourable discounted price. The details of such discounts have not been defined.
- UTC, FISA and BRA will benefit from sales and maintenance service of the COTTONBLEACH system.
- End-user ACT will receive COTTONBLEACH at cost price (no profits charged).
Technical SMEs BRA, FISA and UTC will gain an advantage from being the first entities to receive by the SME-AGs the rights of producing and supplying the technology developed, although the licensing of these rights will not be exclusive. Additionally, the three entities have to ensure that a large group of SMEs will benefit from the post-project completion results, by agreeing on the favourable conditions under which the SME members will access COTTONBLEACH, yet to be defined. The non-exclusive character of the licensing scheme ensures that, in the unlikely case that these SMEs fail in their commercialisation efforts, or the manufacturing / production capacities become overload by market demand, the SME-AGs will have the right to reach further commercial deals with other entities.
In all cases, the licenses granted to BRA, FISA and UTC will be limited in time (a priori 5 years duration) and will be subject to specific milestones (e.g. COTTONBLEACH operative by 2014). The three SMEs have suggested to the SME-AGs to include a 'most favourable license' clause in the agreement, thus assuring that their competitors will not have the possibility of acquiring a better license to COTTONBLEACH in the future. This issue is yet to be discussed, considering that the three SMEs already have an important competitive advantage being the first entities to manufacture and commercialise the technology.
The SME-AGs / SMEs have stated their initial intentions for an exploitation agreement, as beneath summarised.
SME partners have agreed on a joint ownership agreement, which establishes the framework for making use of any of the project results. However, the Head of Agreement were set up from the very beginning.
Considering all the above, the SME-AGs of the project have concluded to the following heads of agreement, which will be revised against future developments and form the basis for the EA to be signed towards the project end:
1. The SME-AGs are the joint owners of all results, information, data and know-how generated by the COTTONBLEACH project, all in accordance with the rules applicable to the project.
2. The SME-AGs agree to own the Joint Foreground in equal shares.
3. The SME-AGs shall enter into good faith discussions and take such steps as may be required to protect the Joint Foreground by a patent or other IP rights, including keeping the Joint Foreground confidential and delaying any publication or other dissemination activity if such activities are likely to prejudice the protection and / or the commercial use of the joint foreground.
4. Each SME-AG may take action for infringement against any third parties that infringe the IP rights of the SME-AGs on the joint foreground. An SME-AG who takes action for infringement against such third parties shall notify the other SME-AGs of the action that has been brought and the SME-AGs may mutually agree on additional measures and actions to be taken against such infringing third parties.
5. Each SME-AG shall have the irrevocable and worldwide right to use the joint foreground in all kinds of further research or parallel research activities, including third party research. Each SME-AG is free to undertake further research and third party research on the joint foreground without compensating the other SME-AGs in any way. Nevertheless, an SME-AG that plans to undertake such activities shall inform the other SME-AGs in advance and sign confidentiality agreements with any third parties that could have access to information and data related to COTTONBLEACH.
6. The SME-AGs shall jointly agree and/or approve any licensing of their joint foreground (COTTONBLEACH) to third parties for commercial use. Licenses to third parties shall always be non-exclusive, unless all SME-AGs approve the granting of an exclusive license in writing. The SME-AGs will strive to implement their initial plan for the manufacturing and exploitation of foreground, as explained above, by licensing the project technological SMEs for that purpose.
7. ATOK, from its position of exploitation manager, shall be responsible for monitoring the efforts of any SMEs to which COTTONBLEACH is licensed, in particular the technological SMEs of the project.
8. Any SME carrying out commercial use in cooperation with third parties shall take reasonable steps and sign agreements in order to ensure that the third parties will observe and perform all confidentiality undertakings with regard to information and data related to COTTONBLEACH.
9. Any enhanced foreground generated by modifications, adaptations, updates, corrections, upgrades, enhancements and developments of the joint foreground shall be the ownership of the SME-AGs, according to their agreement.
10. Each SME-AG undertakes to treat the Joint Foreground as confidential and use reasonable endeavours to procure that the same be kept confidential.
11. Each SME-AG may, at any moment, assign (sell) its share of the Joint Foreground. Nevertheless, such SME-AG shall inform the other SME-AGs of its intention to assign its share and the other SME-AGs shall have a right of first refusal for a period of five months from the notification of the intended assignment. The intention of this is to ensure that the control of the COTTONBLEACH technology stays with the SME-AGs of the project.
12. The SME-AGs agree to share the costs of patenting and/or acquiring a trade mark for commercialising COTTONBLEACH, in equal shares. An SME-AG that decides not to contribute to the costs of IPR protection shall lose its rights to the underlying knowledge and its share of royalties. Nevertheless, any favourable conditions agreed for the SMEs members of the SME-AGs who wish to acquire COTTONBLEACH shall apply also to the members of an SME-AG which does not contribute to the costs of protection and thus loses its share of the royalties and IPR. The objective of the latter agreement is to ensure that the SME members will always benefit from the results of COTTONBLEACH in all cases.
13. Potential licenses may be granted for developers of alternative applications.
The SME-AGs agree that these heads of the exploitation agreement are sufficient until the improvements for COTTONBLEACH are available.
Project website: http://www.cottonbleach.eu
The European Union (EU) textile industry, worth over EUR 119 billion and giving work to more than 1 million people, is a sector in which Small and medium-sized enterprise (SME)s employ 70 % of the workforce in regions where textile plays a vital socioeconomic role. The overall competitiveness of this sector is straining under price competition from outside the EU, especially from the Far East. In addition, European cotton manufacturers are facing a serious competitive threat as cotton loses ground to synthetics on the basis of price, perceived quality and diversity of end-uses.
Global market pressures are compounded by the heavily chemical-dependant nature of the sector, subject to the cost of applying EU environmental legislation. Current bleaching methods use hydrogen peroxide and in much lesser degree, sodium hypochlorite, resulting in fabric damage, formation of toxic by-products and large amounts of water and energy to remove these chemicals.
COTTONBLEACH was born as a new solution for this problem that should improve textile quality while also promotes savings of energy and chemicals by means of the implementation of an innovative and more efficient bleaching process formed by a conjunction of two sequential enzymatic treatments enhanced through the use of ultrasonic techniques that promotes generation of powerful shock waves that cause effective stirring / mixing in the liquid-solid interface, improving homogenisation, solubilisation, mass transport and mass transfer phenomena. The implementation of COTTONBLEACH technology within the conventional process has proved to be capable to provide higher whiteness levels even with lower temperatures and a decrease in chemicals consumption, which provides the basis to reach significant savings in textile industry.
The whole COTTONBLEACH treatment involves a first enzymatic pre-treatment with laccases, enhanced with ultrasonic devices performance, a second enzymatic step with Oxi-MtCDH (an enzyme developed by one member of COTTONBLEACH consortium within the project's life) that results in in-situ hydrogen peroxide production when the optimal conditions for the enzyme are used, and a final bleaching step at lower temperatures improved by ultrasounds energy.
During the 36 months life of COTTONBLEACH project, the consortium has not only carried out numerous Laboratory tests, but also has designed, constructed and validated a final industrial COTTONBLEACH prototype, based on a current machine design which has undergone significant updates to allow implementing the crucial ultrasonic devices. The machine has allowed the consortium to carry out several tests during the lasts months in order to verify the first laboratory results and definitely prove the accomplishment of the technical and scientific objectives.
The COTTONBLEACH consortium comprises Research and technological development (RTD) performers with strong expertise in process ultrasound enhancement and characterisation and development of enzymes, which have been supported by SMEs with expertise in enzyme production and in ultrasound technology. In addition, the consortium has counted also with an SME specialised in textile machinery manufacture, a cotton textile manufacturer / processor end-user and a Spanish textile association, which have conferred the group with the essential know-how and experience to be successful in all its tasks.
Project context and objectives:
The current global economic and financial crisis has severely impacted the textile and clothing industry - predominantly SME-based, with 73 % of the total labour force working in SMEs - with orders and production falling by double digits since October 2008. At the same time this sector is one of the hardest hit by other countries sheltering their local industry from competition.
The sector is still reeling from previous blows: the 2005 abolition of EU textile quotas which has opened the EUR 66 billion value-added European textile market to low-cost Asian producers, and the costs of complying with recently implemented environmental legislation (IPPC and REACH), has an estimated cost of EUR 3.9 billion for the textile industry. In June 2008, the European Council adopted a new reformed EU cotton support scheme, establishing national programs to facilitate cotton industry restructuring in light of the increasing loss of jobs and productivity. In 2007 alone, employment in the sector dropped by 6.4 % or nearly 165 000 employees compared to 2006 for the 27 Member States, one of the highest losses in the last decade.
Consequently, the sector is being forced to minimise operation costs and production losses. The proposed COTTONBLEACH technology was thought as a technological tool to achieve these objectives by reducing fiber damage as well as chemicals and energy consumption, providing a cost effective process to comply with current EU environmental legislation instead of moving cotton finishing jobs to other countries with less strict environmental norms. The SME-AGs behind the project illustrate the need with real examples from their members; company after company moving their bleaching operations to India and China for lack of competitive options in the EU from textile processing companies in compliance with EU environmental standards. Even then, many are uncomfortable with the high health impact of the Asian model and would much prefer to use bleaching technologies with minimal environmental impact. The 'green' nature of COTTONBLEACH ensures that the benefits of this technology will remain in Europe, as Asian textile processors have no environmental concerns to motivate the adoption of green technologies.
Regarding these chemicals used in the abovementioned treatments, the most common bleaching agents employed by the industry are based on sodium hypochlorite (for a limited set of applications) and hydrogen peroxide. Nevertheless, for environmental reasons (possible formation of halogenated organic compounds) the use of chlorine-based components is now limited in Europe to just a few particular cases, associated with knitted fabric and, in some cases, bleaching of yarn when a high degree of whiteness is required. Consequently, H2O2 has gained popularity as a bleaching agent as it is non-yellowing, non-toxic (degradable into water and oxygen), and odourless. In addition, H2O2 does not have the effluent problem that is associated with chlorine bleaching regarding the formation of halogenated compounds. However, such bleaching solutions usually require 40-50 minutes and temperatures of 90 - 100 degrees Celsius to obtain acceptable whiteness values added to the fact that simple solutions of H2O2 are ineffective in bleaching without additives.
Main limitations of existing technologies include:
- Chlorine-based bleaching can cause environmental problems due to the presence of chlorine breakdown products, leading to the formation of AOX and other toxic compounds.
- NaClO bleaching requires special safety measures, increasing the cost of the process.
- Hydrogen peroxide bleaching methods require temperatures close to boiling point to obtain successful whiteness levels and therefore require high energy consumption.
- Traces of hypochlorite and peroxide remain in cotton fabrics and can result in yellowing and damaging fibres, respectively, as well as interfere in dyeing and posterior cotton finishing processes. Therefore, higher amounts of water and energy are needed to remove both from fabrics.
- Extreme pH medium needed both in sodium hypochlorite and hydrogen peroxide bleaching processes produce high environmentally hazardous waste liquors (high BOD and COD levels), requiring expensive water treatments.
Project objectives
As a result of the above issues, the RTDs of the consortium came with an innovative treatment that, within a EU financed Seventh Framework Programme (FP7) project, would end with a pre-competitive prototype that could be further developed that promoted, as the main objective, to obtain a better bleaching process, faster and more efficiently than current peroxide processes.
The general overview of full treatment is shown in the diagram below, which also proves how the additional steps are integrated into the conventional process ones.
The technological and scientific objectives are listed below:
- develop the pre-treatment based on the use of laccase enzymes, cutting the need for H2O2 by 50 % and for rinsing water by 40 %;
- high frequency ultrasound will be tested for first time in this kind of application. The results obtained will be compared with those at low frequencies, comparing the effects on higher radical formation;
- the suitability of pulsed-ultrasound will be tested in order to improve the cost-effectiveness of the system, identifying the proper pulse conditions to achieve a balance between the cost and the bleaching effect. Enhance the bleaching process by ultrasound performance, investigating suitable frequencies (20-600 kHz) and intensities in order to optimise cavitation on an industrial scale;
- develop and find the optimal condition to obtain In-situ H2O2 production by means of glucose oxidase (GOX) which should cover peroxide demand (5.44 g H2O2 / Kg cotton), generating gluconic acid as by-product and thus avoiding the use of chemical stabilisers;
- soften the operational conditions (pH 8-9; temp. 50 degrees Celsius; duration 30 min) reducing energy costs by up to 50 % and minimising fibre damage (also helped by the highly specific enzymes that will affect only non-cellulosic fibres, without damaging the cellulose part in cotton);
- validate with trials all these advantages scaled in a cost-effective pilot plant designed and constructed by the consortium, with optimal integration of the COTTONBLEACH technology, to ensure the proposed 'add-on' system fulfils the objectives;
- obtain an 8% increase over current cotton fabric bleaching levels through classic methods;
- the proposed device, including equipment, installation and maintenance, might have a cost around EUR 60 000.
Project results:
Project objectives were defined in the initial work programme of COTTONBLEACH as Work packages (WP)s and the main tasks were arranged according to the activity and their time requirements. This program might help manage the research and validation work by the partners to assure the fulfilment of the objectives during all project's duration. The SME partners and associations would be involved in the research field, supplying their specific knowledge and experienced know-how, although most part of the innovation must be carried out by the RTD performers.
- WP1 - System specifications
The first stage of the project was considered aiming to provide an overview of cotton manufacturing processes (paying special attention to the bleaching processes), acquire information from the end-users regarding industrials standards from health, safety and manufacturing point of view, legislation and requirements not covered by current technologies.
Moreover, during the first technical meeting of the project, ACATEL (Portuguese finishing textile company, mainly focused on dyeing, mercerising, bleaching, piece dyeing, printing, flocking and finishing of knitted fabrics in rope or garment) and BRAZZOLI (Italian worldwide leading manufacturer in the production of machines for dyeing and finishing of both woven and knitted textiles) shared with the consortium partners their case study with detailed information regarding the production processes that were being carried out in their facilities and technical information about textile machinery.
The studied bleaching processes were two: super white cotton and half bleaching (further dyed), since both cotton treatments represent a big part of their bleaching necessities.
WP2 - Laccase pre-treatment enhanced with ultrasound
During WP2 the influence of laccase pre-treatment in the peroxide bleaching of cotton textiles was evaluated. With the aiming to reduce the amount of hydrogen peroxide consumption in bleaching process, the conditions of enzymatic pre-treatment were optimised for whiteness enhancement.
The first step was to introduce the laccase from Ascomycete Myceliophthora Thermophila, which have proved ability to degrade and oxidise. Various reaction factors were considered to optimise the enzyme pre-treatment for bleaching enhancement such as laccase dosage (0, 1, 4, 6, 10, and 20 U / mL), incubation temperature, and elimination of fabric preparation process. Furthermore, the decrease of hydrogen peroxide consumption was attempted in bleaching process after enzyme pre-treatment. Previously desized and desized / scoured cotton fabrics were incubated in 0.1 M acetate buffer, pH 5, in the presence and absence of laccase enzyme.
After termination of enzyme pretreatment, the fabrics were taken and washed off in warm water for 10 minutes to completely remove the residual enzymes from the surface of fabrics. All the processes of enzyme pre-treatment and bleaching process using hydrogen peroxide were carried out on desized and desized / scoured cotton fabrics.
For each process, the best conditions using ultrasound were set and compared with the results made in conventional equipment. Different ultrasonic powers were studied (30, 60, 90, 120 W) at frequency: 850kHz.
Main results:
a. determination of the most promising source of laccase, namely ascomycete Myceliophthora thermophile;
b. characterisation of the best processing parameters for enzymatic pre-treatment:
b1. the optimum temperature for ensymatic treatment resulted at 50 degrees of Celsius, since the enzyme maintained stable for 1 hour of incubation and lost just 10 % of its activity after 24 h;
b2. the laccase concentration for pre-treatment was optimised (2 U / mL);
b3. the optimum time of incubation was ½ hour;
b4. washing for 10 min. at 50 degrees of Celsius with Lutensol AT25 (1g/L);
b5. 50% of protein adsorption at the moment of pre-treatment on scoured fabrics;
b6. whiteness (W*)= 35 for fabric samples given by ACATEL.
c. Characterisation of the best process conditions of ultrasonic bleaching:
c1. for half-bleaching: 1g / L hydrogen peroxide; 1 g / L sodium hydroxide; 80 degrees of Celsius for 120 min.; 10 min. of washing with tap water (W* equal to 63.5);
c2. for super-white: 8g/L hydrogen peroxide; 4 g/L sodium hydroxide; 80 degrees of Celsius for 1 hour.; 10 min of washing with tap water (W*77.1).
d. determination of the synergistic effect provided by the ultrasounds surrounding the cotton fibres during the bleaching step.
WP3 - Bleaching process characterisation
Within the tasks carried out at WP3, CRIC (RTD) characterised the ultrasonic bleaching enhancement through experimentation at FISA's (SME) facilities, optimising bleaching process under cavitation. Partner FISA is specialist in design, manufacture and sale of automated ultrasound cleaning machines, so they counts with testing laboratories for best cleaning conditions characterisation under ultrasonic fields, equipped with temperature controlled stainless steel vessels, which include piesoelectric and magnetoestrictive transducers.
The extensive experimentation allowed the RTD to identify the most optimal processing parameters to obtain the highest cotton's whiteness. The tested parameters were:
- ultrasounds (two kinds were tested: piesoelectric and magnetoestrictive);
- temperature (70, 90 degrees Celsius);
hydrogen peroxide concentration (2, 4, 8 g / l);
- processing time (30, 60 min).
The final whiteness measurement for each sample that had undergone a different treatment involving a specific combination of parameters was evaluated through a spectrometer, which returns values of Berger's Index, providing reliable information about the cotton's whiteness level and allows doing comparisons between different values. The whiteness increases proportionally to the Berger index.
Main results
a. The calorimetric data allowed evaluating the ultrasonic bleaching enhancement through experimentation, confirming that applying ultrasounds while the bleaching process is being carried out has a positive effect in its efficiency. As it can be observed in the graph below, same raw cotton fabrics, having undergone the same bleaching process with identical operational parameters, resulted in higher whiteness when ultrasonic transducers were working in the vessels.
b. However, there were no significant differences between the results obtained with piesoelectric or magnetoestrictive devices, so it has been not possible to conclude that one kind provides higher whiteness levels than the other.
c. Nevertheless, the results achieved by University of Minho and CRIC during experimentation allowed identifying the piezoelectric technology as the best technique in terms of performance related to costs. Taking into account also power density, and based on the experience cumulated by the experts participating into the project, the power scale-up for the devices was 1 kW.
In addition, further experimentation at FISA's facilities included also the enzymatic pre-treatment before bleaching step, consisting of a 30 minutes process at 50 degrees of Celsius, with ultrasounds and Laccasse concentration of 2 u / ml , since these were the optimal processing conditions, specified by TEM as the conclusion of their laboratory tests. The experimentation within the following bleaching step also allowed obtaining some evidences about how the temperature, processing time and peroxide concentration affected on the final whiteness.
- Comparing the values of WI Berger of all the tests, the whiteness achieved after laccase pre-treatment was significantly higher the obtained under same conditions with conventional bleaching process. Furthermore, it was proved that, even using lower peroxide concentrations, the WI Berger at 90 degrees of Celsius was higher than the maximum achieved during the conventional test.
- The laccase pre-treatment accelerates the bleaching speed, since higher whiteness values were obtained after 30' bleaching process with enzymatic pretreatment than with 60 min conventional process without the first enzymatic step.
- The temperature proved to be the most critical factor to improve the final whiteness. The targeted goal of decreasing the processing temperature till 70 degrees of Celsius had to be reconsidered in future tests carried out in the final pilot plant, since it was not possible to conclude that combining temperature and peroxide reduction would not negatively impact on the whiteness.
WP4 - Peroxide production from desizing waste water
Gras University started performing its work being focused on investigating GOX and its potential within Hydrogen Peroxide production.
Nevertheless, during the project's life, a relatively new highly promising ensyme showed several advantages compared with GOX. Consequently, the interest of the project was modified and the researchers also focused their attention and put higher efforts to compare both and arise with the most promising and suitable Hydrogen Peroxide producer. Advantages linked to CDH are:
(i) its massive production for industrial scale,
(ii) in-situ peroxide production (CDH binds to cotton, producing H2O2 onto the fibre) and,
(iii) being capable to use other monosaccharides as substrate (glucose, cellobiose, lactose, maltose).
Considering these first findings, the following activities, aimed at defining the reaction conditions and treatments for in situ generation of hydrogen peroxide, were carried out during the course of the year:
0. studying the most suitable carbohydrate substrates;
1. production of recombinant Myriococcum Thermophilum MtCDH;
2. study H2O2 production using GOX and Cellobiose Dehydrogenase (CDH);
3. peroxide Production;
4. bleaching process using desizing waters.
A. Studying the most suitable substrate
- GOX requires only glucose as a substrate. However, CDH is able to use other several carbohydrates, especially disaccharides arising from the desizing and scouring processes.
- Different concentrations of carbohydrate substrates (lactose, glucose, maltose, cellobiose) were incubated with CDH, and it was found that the highest concentrations of hydrogen peroxide were produced in the presence of Lactose.
B. Production of recombinant MtCDH
Since the preliminary studies showed many advantages of using CDH instead of GOX, An overnight pre-culture of the Pichia pastoris strain PMTS (carrying the MtCDH gene) was inoculated into 30 L of production stage medium in a 70-L bioreactor, and a total of 700 mg partially purified MtCDH was obtained, which has been used during the project. The final recombinant CDH preparation had a specific activity of 3.5 U mg-1.
In terms of cost, although not commercially available, CDH cost is estimated at around EUR 30/kg lyophilised. However, we expect these costs will be more competitive.
Nine amino acids near the active site were selected for mutation (C291X, N292X, W295X, L324X, T599X, R601X, S699X, N700X and N732X) and libraries with more than 400 clones each have been constructed.
C. Optimising H2O2 production
This task was mainly focused on studying the variables that affects hydrogen peroxide production, doing a higher effort in demonstrating if the presence of gluconic acid, obtained as a b product during the enzymatic production of H2O2, could lead to enhanced stabilisation of hydrogen peroxide acting as the chelating agent substitute.
The activities carried out to characterise the stage of hydrogen peroxide production are:
a. effects of temperature on hydrogen peroxide in the presence of gluconic acid;
b. effect of metals present on the cotton on hydrogen peroxide (in the presence of gluconic acid);
c. comparing the stabilising effect of gluconic acid and dipicolinic acid.
- The effects of the temperature were studied by monitoring during 1 hour the stability of the Hydrogen Peroxide, while it was incubated in 1Mm of gluconic acid. Although there were no significant changes at 50 degrees Celsius, the concentration of hydrogen peroxide at 90 degrees Celsius showed a decomposition more pronounced, so unfortunately, the researchers must assume that, at standard bleaching temperatures, the gluconic acid cannot offer protection to hydrogen peroxide.
- Hydrogen peroxide was incubated during 2 hours in the absence and presence of different metals (cooper, zinc, manganese, calcium) and the hydrogen peroxide concentration was monitored during this period. The amount of hydrogen produced in the absence of the metals was approximately 40 % higher than in the presence of metals.
The metals tends to react with the hydrogen peroxide generating peroxides in the process as well as reacting with acids producing salt and water, so the results of the studies showed how the hydrogen peroxide decreased in the presence of metals directly related to the increase in metal concentration. This effect came from both sides, the peroxide reacts with the metals and the reaction with gluconic acid also shifted the pH, resulting in the destabilisation of hydrogen peroxide.
- The stability of hydrogen peroxide is more pronounced in the presence of sodium silicate as than gluconic acid, but unfortunately, it is also affected by metals, so both gluconic acid and sodium silicate could not protect the hydrogen peroxide decomposition.
Further results
Researchers from University of Gras kept working after the period involved in WP4 and developed a new enzyme called oxyMt-CDH, which can be presented as one of the most important results of COTTONBLEACH Project, and presents a high specificity towards different source of monosaccharide's (100 times more affinity than initial GOX), producing in-situ larger amounts of hydrogen peroxide.
The experimental tests done at CRIC's facilities (WP6 'Industrial validation') were carried out entirely using this new enzyme.
WP5 - Integration and prototype construction
WP5 involved all the work done by the consortium concerning COTTONBLEACH's pilot plant design and construction. The overview of the main results achieved during the previous work allowed describing the best design for the pilot plant, including flow diagrams, CAD files and operational conditions. In addition, the secondary services needed for proper operation were defined at this stage also, as well as the user-friendly software specifications and the essential safety measures.
The final prototype has been constructed, based on a BRAZZOLI finishing machine with a 5 Kg load (concretely INNOLAB HT5) that had to be modified accordingly to COTTONBLEACH innovations requirements, which were studied and defined after gathering all the information from previous work done, and involved the preparation tanks (Laccase solution, CDH solution and bleaching agents), the ultrasonic devices, the side equipment and the control software.
A. Ultrasounds Integration
Ultrasounds interact at two different levels, with concurrent effects. During pretreatment ultrasounds are supposed to boost diffusion rates, while at the bleaching step, are supposed to boost diffusion rates as well as generate radicals able to whitening cotton fibres. For this reason, two different technologies were installed within the equipment: high power and high frequency ultrasonic devices.
(i) High power ultrasounds (HPU)s: 42 piezoelectric transducers (22 KHz) were placed at the main tank bottom, close to the inner basket, where the cotton goods lay. The 50 W transducers were joined by six flanges (3 at each side in parallel) and can be modulated up to 2.1 kW (6 x 7 x 50W).
(ii) High frequency ultrasound (HFU)s): 850 KHs (@ 400 W) Piezoelectric transducers were installed at the recirculation pipe, just before the jet.
B. Preparation Tanks
One tank involves the enzymatic pre-treatment preparation by preparing the laccase solution while the watered solution is heated-up at 50 degrees of Celsius (maximum activity) before filling the housing with the suspension.
Two additional tanks were considered for Hydrogen peroxide production by means of enzymatic reactions. Even though CDH demonstrated better production ratios and flexibility than GOX did, it is in an early stage of development yet, so the prototype was designed to be able to prepare both enzymatic solutions, since GOX has proved to be more robust and commercially available, therefore more competitive from an economic point of view. GOX: the tank reproduces the optimum conditions of temperature, substrate concentration and enzyme concentration, while the system is continuously regenerated and the produced hydrogen peroxide pumped to the system when bleaching.
CDH: The tank prepares the solution (0.05 U / ml), condition temperature (30 degrees Celsius) and desired substrate concentration (between 60 and 100 mg / ml). When the recipe is finished, the content (water + enzymes + substrate) is introduced at the reaction tank, since CDH must bind to cotton to be effective.
C. Side equipment
The prototype as a whole comprises also:
- team generator;
- propane gas installation;
- ultrasonic generators;
- peristaltic pumps to introduce the concentrated solutions and chemicals;
- (Laccase enzyme + Lutensol if necessary, GOX - CDH enzyme, substrate (glucose), bleaching agents).
C. Control system
The elements controlled by this software are:
- BRAZZOLI Machine (reel, pumps, heat exchanger/s, sensors and actuators);
- Steam Boiler (Burner, feed pump, sensors and actuators);
- Side equipment (HPU, HFU, peristaltic pumps, sensors and actuators).
WP6 - Industrial validation
The main goal of this last technical WP was to the study covered the three main innovations of the project, namely laccase pretreatment, ultrasounds enhancement and hydrogen peroxide production; and in depth detail, the parameters studied were water, energy and chemicals consumption, as well as time, temperature and cost.
Potential impact:
The EU textile industry, worth over EUR 119 billion and giving work to more than 1 million people, is a sector in which SMEs employ 70 % of the workforce in regions where textile plays a vital socioeconomic role. The overall competitiveness of this sector is straining under price competition from outside the EU, especially from the Far East. In addition, European cotton manufacturers are facing a serious competitive threat as cotton loses ground to synthetics on the basis of price, perceived quality and diversity of end uses. In June 2008, the European Council adopted the reformed EU cotton support scheme, establishing national restructuring programmes to facilitate cotton industry restructuring and to enhance quality and marketing of the cotton produced.
Global market pressures are compounded by the heavily chemical-dependant nature of the sector, subject to the cost of applying EU environmental legislation. Current bleaching methods use hydrogen peroxide (H2O2) and in much lesser degree, sodium hypochlorite (NaClO, aka bleach), resulting in fabric damage, formation of toxic by-products and large amounts of water and energy to remove these chemicals.
COTTONBLEACH technology will deliver end-user textile AG members with savings reaching 140 000 EUR / year for productions of 1 500 tonnes / yr of fabric (EU average), counting the savings in water, energy and chemicals against the new costs of enzymes and ultrasound. The expected COTTONBLEACH system tag price is of 40 000 EUR for SME-AG associates, a 33 % discount over the full tag price of EUR 60 000. The production cost will be of EUR 28 000, besides an additional fee of EUR 1 000 for the installation and the specification of the equipment. Most end-users have a technical maintenance department making installation costs overheads for them. The costs include the direct and indirect expenses related to staff, investment in machines and manufacturing tools, marketing activities, overheads and other operational activities, representing the 40% of the production costs.
COTTONBLEACH will have a clear economic impact on the production costs associated with water use with savings of EUR 190 000 / year, given the high water demand of the industry. COTTONBLEACH technology will also lower operational temperatures and process duration. Reducing the operating temperature to 40-50 degrees Celsius can cut costs by up to EUR 120 000 / year. Finally, dropping enzyme prices and the cost of ultrasound (EUR 3 / m3 water) ensure the cost-effectiveness of the proposed technology, avoiding the use of H2O2 and stabilisers (EUR 130 000 / annum) and minimising fiber production losses (4 % or EUR 70 000 / annum).
Dissemination activities
The consortium carried out plenty of dissemination activities that had been previously planned within the dissemination actions plan and also a significant amount of additional actions, which involved both publications and events (fairs, seminars, conferences). Among all this activities, also social networking has been encouraged by the creation of Twitter, Facebook and LinkedIn accounts, related to the project.
Exploitation
At the end of the project, the SME-AG / SME partners are still planning to follow the initial business plan, described in section B.3.2 of annex I of the grant agreement. The business plan and the strategies towards exploiting the results have been discussed reiteratively. The consortium has devised an overall plan for the exploitation of Foreground, taking into account that the SME-AGs own all foreground but lack the capacity to exploit it commercially by own efforts. Therefore, they shall reach a commercial agreement with UTC, FISA and BRA, under the following terms:
SME-AGs will grant a manufacturing and commercialisation license to UTC, FISA and BRA for the COTTONBLEACH system. The three companies have reiterated their interest for becoming licensees of the system if real benefits are foreseen.
- In this case, UTC, FISA and BRA will pay royalties to the SME-AGs in exchange of the licensing, concretely 5 % of the gross benefit earn selling the equipment. The royalties percentage will be finally settled when the exploitation takes place. Considering that the target operational cost of EUR 0.16 / Kg cotton has not been yet achieved, the actual percentage of royalties cannot be accurately calculated. Once limitations will be arranged, operational cost will allow the SMEs to calculate their gross profit from the use of COTTONBLEACH and thus would be able to agree on fair and reasonable royalties with the SME-AGs.
- In parallel, the SME-AGs will promote COTTONBLEACH in the textile sector and attract potential customers. On top of the royalties that they receive from UTC, FISA and BRA they will thus gain additional commission-based income for their promotion efforts, calculated as 10% of the gross benefit. Once again, the actual gross benefit needs to be calculated more accurately taking into account the operational cost and therefore the 10 % shall be revised.
- Finally, and with the objective of favouring their associates, the AGs will ensure that UTC, FISA and BRA sell the system to the AG associates at a favourable discounted price. The details of such discounts have not been defined.
- UTC, FISA and BRA will benefit from sales and maintenance service of the COTTONBLEACH system.
- End-user ACT will receive COTTONBLEACH at cost price (no profits charged).
Technical SMEs BRA, FISA and UTC will gain an advantage from being the first entities to receive by the SME-AGs the rights of producing and supplying the technology developed, although the licensing of these rights will not be exclusive. Additionally, the three entities have to ensure that a large group of SMEs will benefit from the post-project completion results, by agreeing on the favourable conditions under which the SME members will access COTTONBLEACH, yet to be defined. The non-exclusive character of the licensing scheme ensures that, in the unlikely case that these SMEs fail in their commercialisation efforts, or the manufacturing / production capacities become overload by market demand, the SME-AGs will have the right to reach further commercial deals with other entities.
In all cases, the licenses granted to BRA, FISA and UTC will be limited in time (a priori 5 years duration) and will be subject to specific milestones (e.g. COTTONBLEACH operative by 2014). The three SMEs have suggested to the SME-AGs to include a 'most favourable license' clause in the agreement, thus assuring that their competitors will not have the possibility of acquiring a better license to COTTONBLEACH in the future. This issue is yet to be discussed, considering that the three SMEs already have an important competitive advantage being the first entities to manufacture and commercialise the technology.
The SME-AGs / SMEs have stated their initial intentions for an exploitation agreement, as beneath summarised.
SME partners have agreed on a joint ownership agreement, which establishes the framework for making use of any of the project results. However, the Head of Agreement were set up from the very beginning.
Considering all the above, the SME-AGs of the project have concluded to the following heads of agreement, which will be revised against future developments and form the basis for the EA to be signed towards the project end:
1. The SME-AGs are the joint owners of all results, information, data and know-how generated by the COTTONBLEACH project, all in accordance with the rules applicable to the project.
2. The SME-AGs agree to own the Joint Foreground in equal shares.
3. The SME-AGs shall enter into good faith discussions and take such steps as may be required to protect the Joint Foreground by a patent or other IP rights, including keeping the Joint Foreground confidential and delaying any publication or other dissemination activity if such activities are likely to prejudice the protection and / or the commercial use of the joint foreground.
4. Each SME-AG may take action for infringement against any third parties that infringe the IP rights of the SME-AGs on the joint foreground. An SME-AG who takes action for infringement against such third parties shall notify the other SME-AGs of the action that has been brought and the SME-AGs may mutually agree on additional measures and actions to be taken against such infringing third parties.
5. Each SME-AG shall have the irrevocable and worldwide right to use the joint foreground in all kinds of further research or parallel research activities, including third party research. Each SME-AG is free to undertake further research and third party research on the joint foreground without compensating the other SME-AGs in any way. Nevertheless, an SME-AG that plans to undertake such activities shall inform the other SME-AGs in advance and sign confidentiality agreements with any third parties that could have access to information and data related to COTTONBLEACH.
6. The SME-AGs shall jointly agree and/or approve any licensing of their joint foreground (COTTONBLEACH) to third parties for commercial use. Licenses to third parties shall always be non-exclusive, unless all SME-AGs approve the granting of an exclusive license in writing. The SME-AGs will strive to implement their initial plan for the manufacturing and exploitation of foreground, as explained above, by licensing the project technological SMEs for that purpose.
7. ATOK, from its position of exploitation manager, shall be responsible for monitoring the efforts of any SMEs to which COTTONBLEACH is licensed, in particular the technological SMEs of the project.
8. Any SME carrying out commercial use in cooperation with third parties shall take reasonable steps and sign agreements in order to ensure that the third parties will observe and perform all confidentiality undertakings with regard to information and data related to COTTONBLEACH.
9. Any enhanced foreground generated by modifications, adaptations, updates, corrections, upgrades, enhancements and developments of the joint foreground shall be the ownership of the SME-AGs, according to their agreement.
10. Each SME-AG undertakes to treat the Joint Foreground as confidential and use reasonable endeavours to procure that the same be kept confidential.
11. Each SME-AG may, at any moment, assign (sell) its share of the Joint Foreground. Nevertheless, such SME-AG shall inform the other SME-AGs of its intention to assign its share and the other SME-AGs shall have a right of first refusal for a period of five months from the notification of the intended assignment. The intention of this is to ensure that the control of the COTTONBLEACH technology stays with the SME-AGs of the project.
12. The SME-AGs agree to share the costs of patenting and/or acquiring a trade mark for commercialising COTTONBLEACH, in equal shares. An SME-AG that decides not to contribute to the costs of IPR protection shall lose its rights to the underlying knowledge and its share of royalties. Nevertheless, any favourable conditions agreed for the SMEs members of the SME-AGs who wish to acquire COTTONBLEACH shall apply also to the members of an SME-AG which does not contribute to the costs of protection and thus loses its share of the royalties and IPR. The objective of the latter agreement is to ensure that the SME members will always benefit from the results of COTTONBLEACH in all cases.
13. Potential licenses may be granted for developers of alternative applications.
The SME-AGs agree that these heads of the exploitation agreement are sufficient until the improvements for COTTONBLEACH are available.
Project website: http://www.cottonbleach.eu