Effect of rice husk co-combustion with coal on gaseous emissions and combustion efficiency

Investigation on co-combustion of Lakhra coal and rice husk blends was carried out in a drop tube furnace to measure its impact on flue gas emissions and carbon burnout. According to experimental results, the emissions of NO and SO2 were higher in case of combustion of Lakhra coal compared to coal-rice husk blends combustion. The emissions of CO decreased rapidly at higher furnace temperatures beyond 900 degrees C. Minimum of CO emissions were nearly 45 ppm while SO2 and NO emissions were found to be 554 and 120 ppm, respectively, for 15% biomass blending ratio and at exit furnace temperature of 1000 degrees C. The unburnt carbon was found to be reduced significantly with an increase in furnace temperature and blending ratio. The study has shown that blending of rice husk would be a useful option to minimize SO2 and NO emissions during combustion of Lakhra coal.