An overview of the main results achieved in the project are described below.
Characterization and pre-processing of MSW from different localizations and seasons
Several OFMSW samples from the EU were characterized showing that despite the heterogeneity and variation in composition, the chemical components of biowaste are usually within a relatively short range of values. Specific requirements and standards for PERCAL’s products based on a review of current petrol or renewable products available in the market were defined. Pretreatment and enzymatic hydrolysis of biowaste were optimized.
Microbial conversion to bioethanol, lactic acid and succinic acid
Fermentation tests with different strains indicate that ethanol yeast, LA and SA bacteria are not inhibited and can effectively use the sugars from OFMSW hydrolysate. The optimization of fermentation of OFMSW into LA achieved conversion yields over 90 %, with L-LA purities up to 98 %. SA to sugar conversion yield was 0.26 g g-1 and productivity was 0.53 g L-1 h-1.
Valorisation of fermentation by-products as surfactants
Regarding biosurfactant production from fermentation by-products the targeted fractions are protein and lipids. PERCAL surfactant was industrially validated for three different detergent applications, showing a good performance compared to a standard formulation.
Green chemical routes to produce solvents, hot melt adhesives and polyols and their further industrial validation
A reactive distillation process for the production of the biosolvent ethyl lactate from ethanol and LA was developed. When ethyl lactate was used as green preservative in cleaning products, promising results were obtained. The synthesis of lactide from LA was carried out at lab scale following a two steps approach. PLA and PLA copolymers were obtained by ring opening polymerization of lactide and used to formulate Hot Melt Adhesives (HMAs) for closing carboard applications, showing improved performance in comparison with fossil-based EVA HMAs. Bio-SA served as raw material for the production of polyester polyols, which were used to produce polyurethane dispersions and for the synthesis of thermoplastic polyurethanes.
Study of adaptation and monitoring of PERSEO plant for the production of bioethanol, LA & SA
A versatile biotechnological plant to produce bioethanol, LA and SA from the OFMSW was studied. PERSEO biorefinery plant, which currently produces bioethanol from OFMSW, was used as a reference to study this versatile biorefinery model. PERSEO plant can be easily adapted for pre-treatment and fermentation processes. The monitoring of critical parameters such as the concentration of glucose, ethanol, LA and SA could be monitored with the NIR technology developed. Overall, this task served as a basis for the development of an industrial biorefinery that uses OFMSW as feedstock for the production of different added value bioproducts.
Environmental, regulatory & economic analyses
The assessment of all pillars underlines that the development of biorefineries using as feedstock the OFMSW and the production of the selected products could be feasible and successful. One of the important achievements is the savings in GHG emissions that arise when OFMW is valorised via bioprocessing. The economic results indicate that the selected products can be competitive in the market when compared to current fossil or bio-based counterparts, while an assessment of social performance also expresses that OFMSW biorefinery can benefit the community by increasing the job opportunities. Finally, it should be stressed that the production process using OFMSW is well aligned to the regulations of the EU and therefore OFMSW is a suitable feedstock for biorefinery development.
Communication, Dissemination, Exploitation, Business plan & Tech. Transfer
Scientific publications, workshops, newsletters, a publicly available technical guide and a final project webinar were prepared. Business models were developed. The identification of exploitation risks, competitors and other market dynamics is expected to help guide future projects and increase the chance of reaching commercialisation. The business models and overall potential of PERCAL technologies were validated by external stakeholders.
