High titer L-lactic acid production from corn stover with minimum wastewater generation and techno-economic evaluation based on Aspen plus modeling

Technological potentials of L-lactic acid production from corn stover feedstock were investigated by experimental and techno-economic studies. An optimal performance with 104.5 g/L in L-lactic acid titer and 71.5% in overall yield from cellulose in corn stover to L-lactic acid using an engineered Pediococcus acidilactici strain were obtained by overcoming several technical barriers. A rigorous Aspen plus model for L-lactic acid production starting from dry dilute acid pretreated and biodetoxified corn stover was developed. The techno-economic analysis shows that the minimum L-lactic acid selling price (MLSP) was $0.523 per kg, which was close to that of the commercial L-lactic acid produced from starch feedstock, and 24% less expensive than that of ethanol from corn stover, even though the xylose utilization was not considered. The study provided a prototype of industrial application and an evaluation model for high titer L-lactic acid production from lignocellulose feedstock. (C) 2015 Elsevier Ltd. All rights reserved.