Advanced technology for biomethane production from organic fraction of municipal solid waste within circular economy framework

Upgrading from biogas to biomethane is currently growing in Europe for economical and sustainable aspects. To date different treatments are proposed to upgrade biogas to a higher fuel standard. Among these, physico-chemical treatments are spreading widely in the biogas technology market. Nevertheless, academic research shows that there is still room for improvement, such as the simultaneous removal of impurities and methane losses. Furthermore, biological algae-based processes have proven to be competitive in CO2 capture and production of high added value products. Their development at full scale is still limited, since the complexity of operation. The need of identifying solutions able to ensure stable conditions inside bioreactors is a key aspect to increase their scale-up. The study presents an extensive laboratory research aimed to identify the best combination in terms of culture broth and inoculum with a view at ensuring convenient microalgae-bacteria co-cultivation system, suitable for biogas upgrading systems. The microalgae biomass used in the experiments was collected from an innovative membrane photo-bioreactor.