Integrated process design and analysis for co-production of biofuels with adipic acid and tetrahydrofuran

Abstract

Here, we developed an integrated process to co-produce biofuels with tetrahydrofuran (THF) and adipic acid (ADA) from lignocellulosic biomass. In addition, an alternative process to produce THF alone was proposed and assessed for their economic and environmental impacts. Using pinch analysis, heat integration was performed to reduce the required energy consumption. A techno-economic analysis determined the minimum selling price (MSP) of biofuel to be $3.03/GGE and $3.52/GGE for the strategies A and B, respectively. To evaluate the effects of changes in various economic parameters, a sensitivity analysis was implemented, which determined the discount rate as the most impactful variable on MSP, followed by the inside battery limits capital investment. An uncertainty analysis showed that changes in the prices of feedstock and byproducts have relatively less impact on the economic stability of the process, whereas changes in the discount rate significantly undermine the economics of the process. Finally, a life-cycle assessment was conducted to determine the environmental impact of the proposed processes. The alternative case is more environmentally beneficial than base case to the electricity produced by burning lignin that replaces fossil fuel-derived electricity. These analyses present directions for technology development to lower the environmental impact and economic costs.