脱脂餐厨垃圾燃烧特性及几种动力学模型结果比较

Combustion characteristics and comparison of several dynamic model results of degreased kitchen waste

利用热重分析仪在空气气氛和不同升温速率下对脱脂餐厨垃圾进行了热重实验.依据热重实验数据,采用4种热分析动力学方法（Coats-Redfern法、Doyle法、Friedman法和分布活化能模型（DAEM））,计算脱脂餐厨垃圾燃烧反应活化能E、反应级数n及频率因子A,并进行比较.结果表明：采用不同的动力学分析处理方法,得出的燃烧动力学参数不同.利用Coats-Redfern法,脱脂餐厨垃圾在燃烧主要阶段（转化率5%-95%）可由一段二级反应过程描述,升温速率30℃/min时活化能为70.9 k J/mol.Doyle法和分布活化能模型计算得到的活化能比较接近,Friedman法计算得到的活化能数值最高.脱脂餐厨垃圾燃烧包含分子键能断裂的一系列复杂、连续反应过程,并获得脱脂餐厨垃圾的燃烧反应活化能随转化率的变化曲线.

The thermo-gravimetric analysis（TGA）were used to carry out the thermo-gravimetric experiment of degreased kitchen waste under different heating rates and air atmosphere. According to the thermo-gravimetric experiment data,the activation energy E,the reaction order n and the frequency factor A of degreased kitchen waste combustion reaction and compares were calculated by using four kinds of thermal analysis kinetics methods（Coats-Redfern,Doyle,Friedman,and distributed activation energy model（DAEM））. The results showed that the pyrolysis kinetic parameters were different by using various methods of dynamics analysis. Degreased kitchen waste could be described by a second order reaction process in combustion stage （transformation rate 5%~95%）as the activation energy was 70.9 kJ/mol at the heating rate of 30℃/min by Coats-Redfern method. The results of Doyle method and DAEM method were relatively close while Friedman method obtained the highest activation energy values. Degreased kitchen waste combustion contains a series of complex and continuous reaction processes of molecular bonds fracture,and obtains the curve that pyrolysis reaction activation energy of degreased kitchen waste is along with the change of transformation rate.