The coal-steam gasification method has been proven to be suitable for power generation. However, the low concentration of CO2 generated in the external coal combustion heating process causes significant CO2 capture energy consumption. As a carbon-neutral fuel, biomass combined with coal-steam gasification could contribute to a reduction in CO2 emissions. In this work, using the typical herbaceous biomass as the heating fuel, the energy efficiency and carbon emissions of the biomass-heating-coal-gasification power generation system (BHCG) are systematically studied. The results indicate that the coupling utilization of biomass and coal can significantly improve the emission reduction characteristics of fossil energy systems. In the no-carbon capture scenario, the power efficiency of BHCG is 50.66%, which is 5.31% higher than GE gasification power generation system. When the carbon capture process is introduced, the power efficiency of BHCG is 46.40% with -133.90 kg CO2/MWh. The biomass heating coal-steam gasification method can utilize the negative carbon utilization of fossil fuels and has high energy efficiency.
Keywords coal gasification, biomass, external-heating, energy efficiency, carbon emission, CCS