Investigations on Combustion and NO Emission Characteristics of Coal and Biomass Blends

Abstract

The effects of biomass ratios, coal types, biomass types, and furnace temperatures on the combustion and NO emission characteristics of coal and biomass blends were investigated using a customized thermogravimetric analysis system which can measure the burning profiles and the NO emissions simultaneously, and at a constant furnace temperature. The results indicated that blending biomass with coals could improve the burning rate of coals, especially the burning rate of the anthracites. Also blending biomass could reduce NO emissions for all types of coals. With the increase of biomass ratio in the coal–biomass blends, the burning rate was found to increase, and both burnout time and the final NO emissions was decreased. It was found that the different volatile contents in biomass could have different impacts on the burning rate of the coal–biomass blends while the nitrogen and ash contents of the different biomass appeared to have different influences on NO emissions. Also, according to the results, with the rise of the furnace temperature, the burning rate of the coal–biomass blends would improve while the NO conversion ratio would increase gradually.