Performance Analysis of Evaporative Biomass Air Turbine Cycle With Gasification for Topping Combustion

Abstract

This paper investigates the performance of a new power cycle, a so called evaporative biomass air turbine (EvGT-BAT) cycle with gasification for topping combustion. The process integrates an externally fired gas turbine (EFGT), an evaporative gas turbine (EvGT), and biomass gasification. Through such integration, the system may provide the potential for adapting features from different advanced solid-fuel-based power generation technologies, e.g., externally fired gas turbine, integrated gasification combined cycle (IGCC), and fluidized bed combustion, thus improving the system performance and reducing the technical difficulties. In the paper, the features of the EvGT-BAT cycle have been addressed. The thermal efficiencies for different integrations of the gasification for topping combustion and the heat recovery have been analyzed. By drying the biomass feedstock, the thermal efficiency of the EvGT-BAT cycle can be increased by more than three percentage points. The impact of the outlet air temperature of the high-temperature heat exchanger has also been studied in the present system. Finally, the size of the gasifier for topping combustion has been compared with the one in IGCC, which illustrates that the gasifier of the studied system can be much smaller compared to IGCC. The results of the study will be useful for the future engineering development of advanced solid fuel power generation technologies.