球型热载体回转窑褐煤热解过程的传热模型

Model of heat transfer of lignite pyrolysis with solid ball heat carrier in rotary kiln

为了了解热载体球煤粉热解过程的传热机理,建立了热载体球回转窑褐煤热解的传热模型并进行了模拟。结果表明:在热载体和煤的初始温度分别为973.15K和373.15K,煤粒径为6mm,热载体与煤质量比为6时,在330s后系统温度达到平衡,约786K。煤颗粒密度的变化以及热解气与热载体对流换热对系统的温度变化的影响较小,反应热对传热速率和平衡温度影响较大。

The model of heat transfer had been established and the model simulation was conducted to under- stand the heat transfer mechanism of the lignite pyrolysis with solid ball heat carrier in rotary kiln. The results in- dicated that the temperature maintains equilibrium at about 786K after 330s, at the initial temperature of solid ball heat carrier and coal particles 973.15K and 373.15K, respectively; the mass ratio of heat carrier to coal was 6; the particle diameter of coal was 6mm. The density change of coal and convective heat transfer had little effect on the temperature. However, heat of reaction of coal pyrolysis had great effect on the temperature.