低挥发分煤燃烧特性及NO_x生成规律的试验研究

Experimental Research on the Combustion and NO_x Generation Characteristics of Low Volatile Coal

利用热天平对低挥发分煤的燃烧过程进行了研究,确定了低挥发分煤的燃烧特性。采用固定床反应器,系统研究低挥发分煤的NOx释放规律。试验结果表明:低挥发分煤的着火温度较高,可燃性较差,稳燃和燃尽性能尚可。随着温度的升高,低挥发分煤的NOx转化率随之降低;对于低挥发分煤而言,存在一个最佳粒径,在此粒径下煤种的NOx转化率最小,不同煤种的最佳煤粉粒径各不相同;当氧浓度增大时,煤种的NOx转化率也相应增加。试验结果与实际锅炉燃烧情况比较吻合,对于锅炉燃烧过程中NOx的控制有一定的参考意义。

Thermogravimetry analysis was used to study the combustion process of low volatile coals in order to ascertain the combustion characteristics of low volatile coals.The paper studied the NOx release characteristics of low volatile coals in a fixed-bed reactor systematic.Experimental results show that the ignition temperatures of low volatile coals are higher than the bituminous and lignite,low volatile coals have poor flammability,but the stable combustion and burn performance can still be.As the temperature increases,emission amount of NOx decreases.There is an optimum particle size for low-volatile coal,which has the minimum conversion rate of the NOx,and the optimum particle size varies with the different coal pulverized.When the oxygen concentration increases,the NOx conversion rate increased accordingly.The result coincide with the actual situation for boiler combustion,which has some guiding significance for controling the emission NOx in combustion process.