An innovative integration of torrefaction, gasification, and solid oxide fuel cell for carbon-neutral utilization of biomass waste: Process development, economic, exergy, advanced exergy, and exergoeconomics analysis

An integrated novel process based on torrefaction, gasification, and solid oxide fuel cell (SOFC) has been developed for biomass waste valorization. Process sustainability analysis has been done through economic, exergy, advanced exergy, and exergoeconomics indicators. According to economic analysis, the internal rate of return (IRR) of this process dropped to 7% at 100-90% of the process efficiency and this process is not economically feasible below 90% operational efficiency. While the subsidized process IRR dropped from 20 to 13% at 100-80% of the process efficiency. Subsidized process is also not economically feasible below 80% process efficiency. The overall process electric power generation potential from SOFC and steam turbine generator is around 1331 kW. Gasifier and HeatXC have the highest exergy destructions (1110.7 and 1220.9 kW) with exergy efficiencies of around 82% and 79%, respectively. Gasifier, HeatXC, and SOFC have significant potential of exergy improvement due to higher avoidable exergy destruction. Therefore, process exergy and economic performance can be improved by targeting these components.