Emissions and furnace gas temperature for electricity generation via co-firing of coal and biomass

Abstract

The emissions of carbon dioxide and nitrogen and sulphur oxides for electricity generation with coal and biomass co-firing are investigated and the furnace gas temperature assessed. The study uses simulation and considers fuel combinations based on two coals (bituminous coal, lignite) and four types of biomass (rice husk, sawdust, chicken litter, refused derived fuel). With increasing biomass, net CO2 emissions are seen to decline significantly for all types of selected biomass, while gross carbon dioxide emissions increase for all blends except bituminous coal/refuse derived fuel, lignite/chicken litter and lignite/refuse derived fuel. The reductions in emissions of nitrogen and sulphur oxides are dependent on the contents of nitrogen and sulphur in the biomass. The results also show for all fuel combinations that increasing the biomass proportion decreases the furnace exit gas temperature.