Sustainability evaluation of biomass direct gasification using chemical looping technology for power generation with and w/o CO2 capture

Sawdust direct gasification using chemical looping with hematite as an oxygen carrier was investigated in a 10 kWth interconnected fluidized bed reactor. This was used to develop a biomass chemical looping gasification combined cycle (BCLGCC) model using Aspen Plus software. A technical analysis of a scaled up, simulated and validated 650 MW power plant using BCLG experimental results and industrial data was conducted. The analysis focused on investigating critical parameters that have a significant effect on syngas quality and quantity, hence optimizing the gasification process to obtain higher energy efficiencies for subsequent power generation. An economic and sustainability assessments comparing BCLGCC with 4 different power generation technologies with and w/o CCS was performed. BCLGCC presents promising economic and environmental results, showing that the efficiencies of the CCS and Non-CCS plants are equal to 36% and 41%, respectively, with a COE (including government renewable energy subsidies) for both CCS and Non-CCS equal to 15.9 ¢/kWh and 12.8 ¢/kWh, both of which are lower than the average COE in the UK (approximately 17.7 ¢/kWh). This highlights the technical and economic potential and feasibility of BCLGCC compared to conventional power generation processes while promoting Bioenergy with Carbon Capture and Storage (BECCS) technology.