Combustion Characteristics And NO_x Generation Model Of Pulverized Coal

Energy is the foundation of human survival and power.With the rapid development of society,energy dependence of the world gradually strengthens.According to the existing energy situation in China,the coal's main position in China's energy consumption in the near future will not change.Therefore,the study of coal combustion and pollutants emissions has profound significances.In the study of pulverized coal combustion characteristic,Most of them adopt gradual thermogravimetric analysis apparatus with the temperature about 1100 ?,and it has bigger difference with the actual furnace combustion temperature(1400 ~ 1500?).Therefore,it is necessary to study combustion characteristic of pulverized coal at high temperature(1400 ~ 1500 ?).In high-temperature condition the characteristics of pulverized coal combustion was studied by self-made bench which could achieve thermal gravimetric measurement at constant temperatures and simulate atmosphere of flue gas.And at the same time NO were measured.Using ignition value in the judgment degree of difficulty for the ignition of pulverized coal has better sensitivity.x1 and the burnout time accord with exponential function,x2 and the burnout time accord with linear function in different temperatures.The model was used to predict the ignition characteristics of pulverized coal at different temperature,and it indicates the model has a high accuracy.Combustion experiments of pulverized coal were conducted in high-temperature atmosphere on self-made bench which could achieve thermal gravimetric measurement at constant temperature.Combined parameters x1 and x2 of proximate analysis and ratio KT1T2 of burnout time were introduced,so as to analyze the influence of proximate analysis and temperature on the burnout characteristics,and build the prediction model about the time needed for burn-out.Results show that the qualitative judgment of burnout time is uncertain based on the proximate analysis;x1?x2 and the burnout time accord with quadratic function in different temperatures.Temperature rise helps to improve the burnout characteristics of pulverized coal;With the same temperature rise,the higher initial temperature,the smaller the increase of early burning weight loss rate;The ratio K T2 T1 of all pulverized coal almost equal at constant temperature T1?T2;The ratio KT1T2 is related to the temperature,and conforms to the linear relationship with logarithmic temperature at constant temperature T1.The model was used to predict the burnout time of pulverized coal at different temperature,and it indicates the model has a high accuracy rate to predict the time needed for burn-out.Considering concrete components of volatile,volatile and coke burning at the same time,NO generation process model is established.NO generation of five kinds of coal are simulated under different temperature,the simulation n results with the experimental results are consistent,the reliability of the model has a certain.