不同温度区间内污泥热解气固相产物特征

Characteristics of products from sewage sludge pyrolysis at various temperature ranges

对城市污水污泥（简称污泥）进行工业分析和热重分析，考察污泥的基本组成和热重特性；采用气相色谱（GC）检测了不同热解温度区间内污泥热解生成的气体产物成分，并利用SEM和BET分别分析了不同热解终温下裂解炭的形貌特征和比表面积。结果表明：污泥热解可以分为水分析出阶段、挥发分析出阶段和焦炭化阶段；不同热解温度区间内污泥热解气体产物的组成有很大差别，热解温度350℃后H2在热解气中的含量快速增加，CH4含量在350～450℃时达到最大值，而CO主要在热解温度为350～750℃时生成，CO2含量随着热解温度的增加迅速下降；随着热解终温的不断升高，裂解炭结构变得越来越疏松，比表面积也随之增大，750℃达到最大值55 m2·g-1。

Municipal sewage sludge （i.e. sludge） at various temperature ranges was analyzed by proximate analysis and thermogravimetric analysis methods. The gaseous components produced by the sludge pyrolysis were detected by gas chromatography （GC）, while the morphology and specific surface area of pyrolytic char measured by SEM and BET techniques, respectively. The results show that the pyrolysis process of sludge can involve water evaporation, organics volatilization and char formation steps. There are obvious differences between the gas components obtained at different ranges of pyrolysis temperature. The H2 content will rapidly increase when pyrolysis temperature is larger than 350℃, the maximum CH4 content obtained when temperature is in 350-450℃, the temperature range generated CO is mainly in 350-750℃, and the CO2 content declines for the whole range of pyrolysis temperature. With rising final temperature of pyrolysis, the char structure becomes more and＆amp;nbsp;more loose and it specific surface area increases. The maximum specific surface area of char produces is 55 m2·g-1 at 750℃.