天津市政污泥热解及燃烧动力学特性的分析

利用热重分析仪,在氮气和空气气氛下分别对天津市政污泥进行热分析实验,并采用热重、微分热重、差示扫描量热等方法分析了市政污泥的热解特性及燃烧特性.实验结果表明城市污泥燃烧热反应可分为4个阶段:水分蒸发析出、污泥有机挥发成分析出燃烧、污泥有机质及固定碳燃烧、燃烧残余物及难分解物的分解.在实验条件下,污泥样品着火温度为277.5,℃,燃尽温度为540,℃.建立了天津市政污泥燃烧动力学模型,采用连续两方程拟合的方式,得到了上述主要阶段的表观活化能Ea和指前因子A.

Analysis of Pyrolysis and Combustion Kinetics Characteristics of Tianjin Municipal Sewage Sludge

In order to study the pyrolysis and combustion kinetics of Tianjin sewage sludge,thermal analysis of Thermogravimetry(TG),Differential Thermogravimetric(DTG)and Differential Scanning Calorimetry(DSC)were conducted with a thermal gravimetric analyzer in both nitrogen and air atmosphere.Experimental results show that the whole combustion process of sewage sludge could be divided into four stages:water evaporation,evaporation and sequential combustion of sludge volatiles,combustion of organic matter and fixed carbon,and the thermal decomposition of residues.Ignition temperature of the sludge samples was observed to be 277.5,℃ and the temperature for complete burning was 540,℃.In this research,the mathematical model was established for the pyrolysis and combustion process of Tianjin sewage sludge and the apparent activation energy Ea and pre-exponential factor A were determined in the above main stages and by using the continuity equation fitting method.