采用管式炉热解装置,在700~1000℃温度范围内对不同含水率的生物污泥进行中高温常压热解实验,研究了加热模式、热解终温、物料含水率及升温速率对热解产物产率及气相产物组成的影响规律.结果表明:待温度达到设定温度后,迅速将物料送入反应区的加热模式有利于得到高品质燃气;高温能减少固体碳和焦油的生成,促进富氢气体产生;同时,随着物料含水率的增加,氢气体积分数从17%提高到36%,当含水率为84%时,H2+CO的含量(体积分数)达到最大值;提高热解升温速率能使气相产物产率得到相应增加.湿污泥在高温条件下进行的快速热解过程,一次性完成了污泥干燥、热解和气化,更有利于氢气组分和其他可燃气体的生成,所得气体热值高达12MJ.m-3以上.
Pyrolysis experiments for sewage sludge with different moisture contents were performed at temperatures of 700~1000℃ and at atmospheric pressure in a tubular furnace. Pyrolysis conditions,such as heating mode,final pyrolysis temperature,moisture content and heating rate were analyzed to determine how they affect the characteristics of the resulting gas,liquid and solid residue. The results indicated that high quality flammable gas could be obtained when sludge was sent into the reactor at the settling temperature; the yields of solid and liquid could be reduced at a high temperature which favored the production of hydrogen-rich gases. The H2 content of the gas product rose from 17% to 36% as the moisture content of sewage sludge increased,and H2+CO content reached the highest level at a moisture content of 84%; in addition,the gas yield could also be increased at higher heating rates. In this process,the drying,pyrolysis and gasification of sewage sludge were completed in a single thermal process,and the calorific value of generated gas could reach over 12 MJ·m-3.