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动力煤的绝热燃烧温度ta是煤粉锅炉热力计算中最重要的参数之一。绝热燃烧温度与炉膛出口烟气温度之差(ta t’f’)决定了炉膛受热面(包括水冷壁和屏式过热器)的吸热量。文中计算了158种中国动力煤的绝热燃烧温度并且讨论了动力煤的特性参数对绝热燃烧温度的影响。计算结果表明:随着低位发热量数值的提高(Qnet,ar10.84~29.49 MJ/kg)),中国动力煤的绝热燃烧温度从1 458℃提高到1 959℃,理论绝热燃烧温度ta0大约比绝热燃烧温度ta高254~352℃。低位发热量数值对绝热燃烧温度有近似线性的正面影响。对于中国动力煤而言,w(Car)是影响Qnet,ar的最重要正面参数,w(Mar)是影响Qnet,ar的最重要负面参数。此外,由煤的w(Vdaf)决定的过量空气系数对ta具有非线性的负面影响。
Thermal coal adiabatic combustion temperature ta is one of the most important parameters in the thermal calculation of pulverized coal boilers. The difference between the adiabatic combustion temperature and the flue gas temperature at the exit of the furnace (ta t’f ’) determines the amount of heat absorbed by the furnace’s heating surface, including the water wall and the screen superheater. In this paper, the adiabatic combustion temperatures of 158 kinds of Chinese thermal coal are calculated and the influence of the parameters of thermal coal on adiabatic combustion temperature is discussed. The calculation results show that the adiabatic combustion temperature of China’s thermal coal increases from 1 458 ℃ to 1 959 ℃ with the increase of the lower heat value (Qnet, ar10.84 ~ 29.49 MJ / kg). The theoretical adiabatic combustion temperature ta0 is about Adiabatic combustion temperature ta 254 ~ 352 ℃. The low calorific value has an approximately linear positive effect on adiabatic combustion temperature. For China’s thermal coal, w (Car) is the most important positive parameter affecting Qnet, ar, and w (Mar) is the most important negative parameter affecting Qnet, ar. In addition, the excess air coefficient determined by the w (Vdaf) of coal has a non-linear negative effect on ta.