| Nowadays, human is facing the problems of deteriorating global environment and energy shortages, and the use of biomass energy can be an effective solution to our energy security and environmental issues.By TGA, the work makes research on property parameters of corn stalks pellets and wood pellets, and the appropriate combustion kinetics model was established. Using corn stalks pellets and wood pellets as fuels, the emission of pollutants of biomass heating furnace's ignition process and extinction process was researched at the condition of different Combustion air temperature and different Furnace temperature. By thermal balance test, we make research on function relations between the thermal efficiency and the excess air ratio. The work uses Fluent to simulate the combustion process of the heating furnace.Research results are as follows:at the stage of volatile precipitating and burning, activation energy and frequency factor of the two biomass fuels will increase with the increasing of heating rate, while at the stage of coke burning, the discipline is just reversed. So it is conducive for coke burning to increase heating rate. The emission of pollutants of ignition process is more than that of steady state; Increasing the combustion air temperature and enhancing the furnace insulation can reduce CO emissions; During ignition process, for wood pellets, the power relationship between the mass concentration ratio of CO and NO and the exhaust gas temperature is found; for corn stalks pellets, the mass concentration ratio of CO emissions and NO emissions decrease exponentially with exhaust gas temperature. Therefore, emission of one pollutant is closely related with the emissions of other pollutants. The thermal efficiency will significantly increase with reduce of the excess air ratio. The secondary combustion air increased the airflow disturbance in the furnace, and it also generated local cyclone near the wall region, which extend the residence time of air in the furnace.
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