Thermodynamic analysis of the biomass gasification Allam cycle

Abstract

The Allam cycle is a promising oxy-fuel combustion systems featuring high electricity efficiency and carbon capture level. In this paper, a novel biomass gasification Allam cycle is proposed. The thermodynamic performance of the system is studied, and the influence of the turbine inlet temperature, inlet and outlet pressure, and carbon capture pressure on the system efficiency is evaluated. The energy and exergy efficiency of the system is 38.80% and 40.74%. The exergy destruction of the overall system is 332.57 MW, where the gasifier has the highest exergy destruction ratio of 49.77%. As the turbine inlet temperature increases, the energy and exergy efficiency of the system improve by approximately 2.50% and 2.00%, respectively. The thermodynamic performance of the system enhances while increasing the turbine outlet pressure, whereas the system efficiency declines with higher turbine inlet pressure. As the carbon capture pressure increases, the energy and exergy efficiency decrease by 2.00% and 1.00%, respectively. The highest energy and exergy efficiency of the system could reach 40.88% and 42.20%. This work presents a practical method for efficiently utilizing biomass gasification for power generation.