污水污泥流化床气化焦油的化学组成分析

摘要

以空气为气化剂、并通过GC-MS分析,研究了污水污泥流化床气化时气化温度(650、750和850℃)和污泥性质对污泥气化焦油产率及其化学组成的影响.结果表明,污泥气化焦油产率随气化温度的升高而降低,且厌氧消化污泥气化焦油的产率比未消化污泥的低.污泥气化焦油中的化学组成可分为五类:脂肪族化合物、脂环化合物、芳香烃、芳香烃衍生物和杂环化合物.随气化温度的升高,A2/O工艺的未消化污泥气化生成的焦油中脂肪族化合物和脂环化合物的产率均明显降低,芳香烃衍生物的产率则有显著地提高,而芳香烃和杂环化合物的产率均先增加后减少.气化温度为650℃时,活性污泥法消化污泥气化焦油中五类有机物的产率均低于未消化污泥的,而A2/O工艺消化污泥气化焦油中芳香烃产率高于未消化污泥的,其他四种有机物的产率则均低于未消化污泥的.%The influence of the gasification temperature(650, 750 and 850℃)and sludge types on the yield and chemical compositions of tar produced by the air gasification of sewage sludge in a fluidized bed gasifier was studied by GC-MS analysis.The results show that the yields of tar decrease with gasification temperature increasing, and the yields of tar from anaerobic digestion sludge gasification are lower than that from indigested sludge gasification.The chemical compositions of tar can be divided into five categories: aliphatic compounds, alicyclic compounds, aromatic hydrocarbons, aromatic hydrocarbon derivatives and heterocyclic compounds.When the gasification temperature increases, the yields of aliphatic and alicyclic compounds in the tar from the gasification of indigestion sludge produced by Anaerobic-Anoxic-Oxic (A2/O) process decrease;the yields of aromatic hydrocarbon derivatives in the tar increase;and the yields of aromatic hydrocarbons and heterocyclic compounds firstly increase and then decrease.At 650℃, the yields of all the organic compounds in the tar from the gasification of digestion sludge produced by activated sludge process are lower than that from the indigestion sludge gasification;the yields of aromatic hydrocarbons in the tar from the gasification of the digestion sludge produced by A2/O process are higher than that from the indigestion sludge gasification;and the yields of the other organic compounds are lower than that for the indigestion sludge gasification.