Thermodynamic and economic performance comparison of biomass gasification oxy-fuel combustion power plant in different gasifying atmospheres using advanced exergy and exergoeconomic approach

Regarding the growing concern about carbon emission and environmental pollution, biomass has received extensive attention as renewable energy because of environmentally friendly and carbon-neutral. To enhance the utilization of biomass energy and reduce carbon emission, a biomass gasification oxy-fuel combustion power system is established. Advanced exergy and exergoeconomic analyses are applied to evaluate the system in different gasifying atmospheres of air, steam, and air/steam. The air, steam, and air/steam systems have exergy destruction of 155.9 MW, 163.2 MW, and 199.5 MW, and exergy efficiency of 43.47%, 49.48%, and 40.17%. The operating cost of the air, steam, and air/steam system is 305556.4 $/h, 393550.0 $/h, and 276284.8 $/h, and the annualized cost is 64.1 M$, 74.7 M$, and 63.9 M$, respectively. The thermodynamic improvement potential is 25.97% for the air system, 32.29% for the steam system, and 24.91% for the air/steam system. The avoidable cost ratios of the three systems are above 70%, suggesting a high cost-saving potential. The results reveal the effects of gasifying agents on the biomass gasification power system. Strategies are proposed for system improvement based on the advanced exergy and exergoeconomic analysis.