Technoeconomic and Environmental Assessment of Biomass Chemical Looping Gasification for Advanced Biofuel Production

Abstract

Chemical looping gasification is a promising biomass conversion technology that could produce sustainable liquid transportation fuels on a large scale to reduce fossil fuel dependency. The current paper examines the technical, economic, and environmental performance of a biomass-to-liquid (BtL) process based on chemical looping gasification and Fischer-Tropsch synthesis. Two biomass feedstocks, i.e., pine forest residues and wheat straw, are selected for assessing the complete BtL production chain. The results of process simulations showed that both biomass types are suitable gasification feedstocks, with an overall energy efficiency of 53% and 52% for pine residues and wheat straw, respectively. The economic results show that the breakeven selling prices (BESP) are €816 and €781 per m3 for the pine forest residues and wheat straw pellets, respectively. However, if low-grade excess heat valorisation and CO2 credits are considered, the BESPs could meet or become lower than the target value of €700 per m3, making the BtL plant competitive with other biofuel plants. The CO2 avoidance cost is estimated at €74.4/tCO2 for pine residues and €61.3/tCO2 for wheat straw, when replacing fossil fuels. The results of the life cycle assessment study showed that the produced biofuels fulfil the requirements of the EU Renewable Energy Directive II, achieving the reduction in greenhouse gases emissions of up to 79% without carbon capture and storage (CCS) and up to 264% with CCS compared to fossil fuels.