Techno-economic and environmental sustainability assessment of succinic acid production from municipal biowaste using an electrochemical membrane bioreactor

The techno-economic and environmental performance of succinic acid (SA) production by an engineering Yarrowia lipolytica strain has been evaluated in a process using the organic fraction of municipal solid waste (OFMSW) as feedstock and a novel electrochemical membrane bioreactor (EMB) for simultaneous SA production and extraction. The minimum selling price (MSP) of SA ($2.70-3.71/kg) considering 50,000 t(SA)/year production capacity using the EMB-based process was slightly lower than the conventional bioprocess depending on OFMSW management fees ($0-35/t(OFMSW)). Life Cycle Assessment was carried out for the EMB-based bioprocess and the conventional bioprocess considering either conventional electricity production mix (grid) or renewable electricity production from photovoltaics. The use of renewable electricity in the EMB-based bioprocess led to lower Global Warming Potential (0.81 kg CO2-eq/kg(SA)), Abiotic Depletion Potential (15.71 MJ/kg(SA)), Acidification Potential (1.87 kg SO2-eq/kg(SA)) and Eutrophication Potential (0.25 kg PO4-eq/kg(SA)) than the conventional bioprocess when renewable electricity was used, while higher Human Toxicity Potential (0.29 kg DCB-eq/kg(SA)) was observed due to the raw materials (e.g. heavy metals) and utilities (e.g. electricity) used in photovoltaics production. It has been demonstrated that the EMB-based system could improve the sustainability of SA production.