Process design and economic evaluation of integrated, multi‐product biorefineries for the co‐production of bio‐energy, succinic acid, and polyhydroxybutyrate (PHB) from sugarcane bagasse and trash lignocelluloses

Abstract

Abstract This study investigates whether a biorefinery, annexed to an existing sugar mill and co‐producing succinic acid, polyhydroxybutyrate (PHB), and electricity from sugarcane bagasse and trash lignocelluloses, will be a viable investment opportunity for existing sugarcane mills. Four scenarios were simulated in Aspen Plus® and were included in the economic analysis. Scenario A involved the production of PHB and electricity; Scenario B the production of PHB, succinic acid, and electricity; Scenario C the production of succinic acid and electricity; and Scenario D involved the production of electricity only. The most favorable configuration was found for Scenario B where PHB was produced from 25% of the fermentable glucose stream, and succinic acid from the hemicellulose hydrolysate together with 75% of the glucose, resulting in an internal rate of return (IRR) of 24.1% with a net present value of US$477.2 million. Alternatively, Scenario D could be selected if low capital (130.1 million US$) and operational costs (US$13.2 million) are desired, although weak returns (IRR 10.3% and net present value of US$6.08 million) were observed for an electricity price of 0.08 US$ kWh −1 . © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd