不同温度下污泥水蒸气气化合成气的生成特性

Characterization of Syngas Production from Municipal Wastewater Sewage Sludge Steam Gasification at Various Temperatures

采用小型管式气化炉开展不同温度下污泥水蒸气气化实验,分析温度对污泥气化冷煤气效率η_l、污泥碳转化效率η_c、有机相转化效率η_v、以及气化合成气生成特性的影响规律。结果表明:气化温度对η_l、η_c、η_v均具有显著影响,提高温度有利于污泥蕴藏的化学能更多地转化为富氢合成气的化学能,促进污泥碳和有机组分气化反应发生,从而提高污泥能源转化率;气化温度从650℃提高至1 050℃,气相产物产率从38.5 g/100 g DSS(干污泥)增至57.9 g/100 g DSS,其中H_2和CO生成总量最高;另外,延长污泥高温气化停留时间,能够显著增加合成气中H_2生成量。

A series of sewage sludge gasification experiments were carried out using an external heat-pipe electric furnace evolved with high temperature steam as gasification medium. Influences of gasification temperature on cold gasification efficiency ηl of the sludge,carbon conversion efficiency η_c,organic phase conversion efficiency ηv,and syngas production characteristics were investigated. The results show that the ηl,ηcand ηvvalues increased evidently as the gasification temperature increased. An increased gasification temperature is helpful to convert the chemical energy of sludge into the chemical energy of the generated syngas and to improve the conversation efficiency of C and organic substances. The syngas field is increased from 38.5 g/100 g DSS to 57.9 g/100 g DSS when gasification temperature varied from 650 ℃ to 950 ℃.The contents of H2 and CO were the highest among all the detected components of syngas,and the content of CO2 was decreased as the temperature increased. Meanwhile,it can be noted that an extended residence time is more beneficent to produce more amounts of H2.