A promising technical route for converting lignocellulose to bio-jet fuels based on bioconversion of biomass and coupling of aqueous ethanol: A techno-economic assessment

Abstract

A process for production of bio-jet fuel (sustainable aviation fuel, SAF) from lignocellulosic biomass by a novel technical route was designed. Techno-economic assessment of the process was further performed in the Chinese context. The route primarily included a first step of bioethanol production from bioconversion of biomass and a second step of hydrocarbon fuel production from aqueous ethanol by C–C coupling followed by hydrodeoxygenation (HDO). Two Cases were considered, in which wheat straw (WS, Case I) and industrial cellulosic residue (ICR, Case II) were employed as feedstock, respectively. As revealed by the assessment results, the consumption of biomass feedstock is 7.2 tonnes WS (5 % moisture content) or 16.0 tonnes ICR (45 % moisture content)/tonne bio-jet fuel for Case I and II processes, respectively. For a plant with an annual capacity of ∼20,000 tonnes bio-jet fuel, a total capital investment of 382 MM CNY is needed for Case I project, while 368 MM CNY needed for Case II project. The minimal selling prices (MSPs) of the bio-jet fuel to achieve zero net present value (NPV = 0) at a discount rate of 10 % are 12,258 CNY/tonne and 8952 CNY/tonne for Case I and II processes, respectively. The price of WS or ICR is the most sensitive factor affecting the MSP. For Case II project, the selling price of by-product steam also shows very significant impact on the MSP. Monte-Carlo simulation for risk analysis suggests that there is a high probability (96.66 %) for Case I plant to be profitable, while the probability of Case II plant is even as high as 99.99 % at the current price of bio-jet fuel (15,000 CNY/tonne). This work thus can provide important economic information for production of bio-jet fuel from lignocellulosic biomass by this novel route.