Design and evaluation of intensified downstream technologies towards feasible lactic acid bioproduction

Abstract The bio-production of lactic acid (LA) has gained great attention thanks to its versatility as building block with potential environmental and energy benefits. During its bio-production, one of its bottlenecks is the downstream processing, where process intensification plays a significant role to increase process profitability. This work presents a techno-economic assessment for LA bio-production process from the residues of the sugar industry in the Latin-American context, using different separation and purification technologies, namely reactive distillation, liquid-liquid reactive extraction and electrodialysis. A specific methodology to design each separation systems is presented, which employs Aspen Plus, Matlab and their combination. The simulation results indicate the potential of the emerging technologies (i.e. liquid-liquid reactive extraction, electrodialysis) compared to reactive distillation. Taking reactive distillation as baseline, reactive extraction showed a reduction 44% in total annual cost (TAC) and operational expenditures (OPEX), while electrodialysis reduced 55% in TAC and 62% in OPEX. As consequence, the return of the investment is substantially faster for the new technologies. Despite the different TRL among technologies, this result shows the tremendous potential for further developing the intensified reactive extraction and a potential integrated electrodialysis membrane bioreactor, to make the LA bioprocess more profitable thus promoting its use beyond commodities.