生活垃圾与煤混合燃烧特性及动力学分析

Combustion characteristics and kinetic analysis of living garbage and coal blends

利用热重分析仪对生活垃圾与煤混合试样的燃烧特性及热反应动力学进行了实验研究,考察了不同配比混合试样的着火温度、燃尽温度、最大燃烧速率及最大燃烧速率温度等燃烧特征参数,并用Coats-Redfern积分法对其进行了燃烧动力学分析,确定了燃烧动力学方程,求出了反应活化能Ea及指前因子A。实验结果表明:生活垃圾与煤混合燃烧时均保持各自的燃烧特性;混合燃料中随着生活垃圾掺量的增加,热重曲线向低温区转移,燃尽点逐渐降低,综合燃烧特性指数明显增大,生活垃圾能改善煤的燃烧性能;生活垃圾及其与煤混合燃烧出现两个燃烧阶段,分别遵循二级和一级反应机理,煤燃烧只出现一个燃烧阶段,遵循一级反应机理;混合燃料燃烧反应活化能Ea与指前因子A存在动力学补偿效应。

Experimental research on combustion characteristics and thermal reaction dynamics of Living garbage and coal blends was conducted with thermo-gravimetric analyzer. The combustion characteristic parameters such as ignition temperature,burnout temperature,maximum combustion rate and peak temperature at maximum weight loss rate of samples in different ratios were investigated by thermo-gravimetric analysis. Besides,using the Coats-Redfern integral method,the combustion dynamics equations were determined and activation energy（ Ea） and pre-exponential factor（ A） were calculated by the combustion dynamics analysis for samples in different ratios. The results illustrate that living garbage and coal keep their own individual combustion characteristics in blend combustion. With the increase of dosage of living garbage in the mixed fuel,thermo-gravimetric curve gradually shifted to low temperature zone,burning point reduced,the comprehensive combustion characteristic index increased obviously,and living garbage can improve the combustion performance of coal. There are two combustion phases when living garbage are mixed burning with coal fuel,respectively following the second and the first order reaction mechanism. Only one combustion phase is observed in coal burning and follows the first order reaction mechanism. Activation energy（ Ea） and pre-exponential factor（ A） occur kinetic compensation effect in blend combustion.