废轮胎热解半焦CO_2气化反应动力学

GASIFICATION KINETICS OF WASTE TIRE CHAR WITH CO_2

利用热重 差热 (TG DTA)分析仪对废轮胎热解半焦进行气化反应的研究。反应气体为CO2 ,在 2 0℃～ 110 0℃温度范围内以不同的加热速率 ( 10℃ min ,3 0℃ min ,5 0℃ min)对各种热解条件下制得的废轮胎半焦进行气化动力学研究 ,分析了升温速率、制焦条件等对半焦气化反应特性的影响。得到废轮胎热解半焦与CO2 气化反应的动力学参数。建立了废轮胎半焦CO2 气化反应一级动力学模型 ,模型与实验结果吻合良好。

Gasification of char obtained from pyrolysis scrap tires with CO 2 was studied in details. Thermogravimetric study was carried out under the condition of the constant CO 2 pressure with different heating rates(10?℃/min,30?℃/min,50?℃/min)in a wide temperature range of 20?℃～1?100?℃. The sample was obtained from an extra-heating rotary kiln where tires were pyrolyzed under various operation conditions. The gasification took place at the temperature over 800?℃ and the activity energy ranged between 248?kJ/mol and 383?kJ/mol. The influence of heating rates and pyrolysis condition on reaction rate of char gasification was discussed. The temperature of pyrolysis shows remarkable effect on char gasification. The higher pyrolysis temperature is, the lower activity of gasification reaction is, owing to high temperature decreasing the surface area of char pores, whereas rotating speed of rotary kiln has little influence on gasification of the char pyrolyzed from waste tires. There was a shift to high temperature with increasing heating rate. A one-stage reaction model of char gasification with CO 2 was proposed, which agrees well with the experimental data.