The SPIRALG project is a spirulina biorefinery project involving three distinct phases which are separate in time and in space (localised in each partners premises: Sardinia, South of France and North of France). The spirulina biomass produced in Sardinia (Italy) is transferred to the south of France (Mèze) to undergo phycocyanin and co-product extraction. One co-product (after phycocyanin extraction) is then shipped to the North of France (St Lô) to be processed and investigated in terms of amino-acid fractions for plant/soil and Animal & human health applications.
The spirulina biomass production unit established by LIVEGREEN in Sardinia (WP1) reached a total 7.5 MT dw/year. Achievement are:
a- An extensive data set is now available and is still carrying on (temperature, irradiance, pH, O2 saturation, biomass, phycocyanin content)
b- The variation of phycocyanin content has been stabilised, which was required by Greensea for processing the biomass in the view of phycocyanin and co-product extraction. The last year 2022 provided biomass with a constant phycocyanin content stabilised at 10%
c- Seasonal variation of phycocyanin content remains slightly (9-11%)
d- Automation was implemented on 70-80% of the process units on site, only the analytical procedures in the ponds are left manual notably for pH control, which requires a large investment.
e- The Global warming impact (carbon footprint) was reduced by 30% thanks to the use heat from the neighbouring biogas unit to dry the biomass
f- The use of alternative nutrients (Ammonium sulfate extracted from the digestate) can reduce the Total Production cost up to 30%.
The produced Spirulina biomass, was stabilised by drying and was delivered as “spaghetti” powder is of food grade quality able to be exploited within the food and health markets. The produced dry spirulina biomass was sent to Greensea in Mèze, France, where the spirulina biomass biorefinery processes and equipment were established with the aim to achieve 8 metric tons (MT) per year (DOA) of phycocyanin product and develop additional co-products suitable for commercial valorization while using more than 80% of the spirulina biomass.
The major outcomes are the following:
a- The extraction line, still installed in the current building, can produce up to 8MT dw Food grade phycocyanin / year
b- The extraction line shall be fully operational in the new building, productions can increase to a maximum of 17.5 MT dw Food grade phycocyanin / year (TRL 8).
c- The acquired equipment is designed to process up to 17.5 MT of dw spirulina biomass / year
d- Two co-products could be defined and developed which show potential for commercial application.
e- The recovery yield of all extracts (blue extract + Co-A + Co-D) is > 80% , i.e. 80% of the incoming spirulina biomass is recovered (DOA).
f- The valorisation of filtration plates by digestion trials (Biomethane potential) can be processed in the view of a 100% valorisation target
g- Co-A is commercialised within the Bluephyline range
h- Co-D has started to be commercialised within Greensea as a Cosmetic ingredient.
Coproduct A (Co-A) was shipped to Algaia for investigating the protein fraction and potential applications in the plant and animal health sectors.
a- In vitro horse trials showed that Co-A increased fermentation indicating a probable prebiotic effect.
b- Agronomic trials on lettuces revealed that Pil3Ret15 could be positioned as a good organic foliar fertilizer for short cycle annual crops (such as lettuces),
c- Bioactivity assay for Human health applications were undertaken with CoA and Co-D extracts. These screening in-vitro trials showed PilRet15 with very interesting properties in terms of cardio-vascular protection.
d- Overall results show that Co-A can be fully valorised as Feed material but also Food (prototyped product with Livegreen) and more refined extracts can also be commercialised as plant fertiliser in the EU (or biostimulant outside the EU).
The Life Cycle Assessment (LCA) was re-analysed the last year in order to update the data collected in 2019, but also to integrate the improvements done since the beginning of the project. Results show that:
a- Since 2019 Livegreen has integrated the use of biogas for heating the ponds and drying the Biomass as well as reduced the input of Sodium Bicarbonate. These improvements have reduced by 30% the overall impacts generated by Livegreen alone and by 27% for the global Spiralg biorefinery. In these terms the objective of Spiralg has been more than achieved.
b- A Life Cycle Costing Analysis has been undertaken with a consistent set of data which shows that by using alternative nutrients provided by local side-streams (Ammonia sulfate) the Total Production costs can be reduced by 10 - 30%.
The Business Plan (BP) was built on three scenarios:and a total of 8 products (were analysed in the biorefinery scenarios. Results show that the industrial scale biorefinery presented the best margins and profitable outcomes from year 3 onwards. However, the margins fluctuated between the products and hence between the partners. The main challenge will now be to establish the business agreement so all partners can benefit equally on all outcoming products.
