Energy requirements and economics of ABE extractive fermentation: a
solvent-based comparative assessment
Abstract
The reindustrialization of Acetone-Butanol-Ethanol (ABE) fermentation is
hampered by its significant production cost, linked to high product
inhibition and low product yield. ABE fermentation can be significantly
enhanced by integrating in situ liquid-liquid extraction. In this study,
hybrid simulations using Excel® and ASPEN Plus® based on experimental
data were performed to quantify the energy requirements and economic
improvement of the overall ABE extractive fermentation process. Four
scenarios, based on two different organic solvents (2-butyl-1-octanol,
2B1O, and a vegetable oil, VO) applied in batch or fed-batch operation,
were compared with the conventional process. Total energy demand
decreased in all extractive configurations and the greatest energy
savings (61%) were reached with the VO-based fed-batch operation.
However, the highest profit increase was achieved with 2B1O in fed-batch
mode, reducing the minimum butanol selling price by 29% over the base
case, along with 34% savings in raw materials and 80% wastewater
reduction.