【摘要】 针对上海市污水污泥,以提高热解气体、抑制热解焦油为目标,利用两段固定床反应器,研究二次热解温度对污泥一次热解挥发分的热解特性的影响。利用气相色谱定量研究不同二次热解温度下热解气中H2、CO、CO2、CH4的含量变化。利用全二维气相色谱-飞行时间质谱联用仪(GC×GC-TOFMS)定性研究不同二次热解温度下热解油化学组分。结果表明:二次热解温度高于600℃时,热解气体产率明显增加,液体产率明显减少。这表明,在仅改变上段固定床二次热解温度的条件下,一部分污泥热解油通过高温二次热解转化为气体。其中CH4是受二次热解影响最大的气体,相比于一次热解,当二次热解温度高达700℃时,CH4的累计释放量增加了7.0倍,这表明热效应明显促进了污泥热解挥发分的脱甲烷反应。为了更好地揭示污泥热解油转化成热解气的机理,运用GC×GC-TOFMS分析污泥热解油中上千种化合物。我们猜测长链脂肪含氮化合物主要通过脱甲烷反应产生CH4。酮类通过脱羧反应生成CO。更多还原

【Abstract】 The sewage sludge was pyrolyzed in a fixed bed reactor at a heating rate of 10 ℃and a final temperature of 700 ℃,and the resultant volatiles were allowed to be secondarily cracked through a tubular reactor in a temperature range of 500⁷00 ℃.The thermal effect on the cracking of tar was investigated.It was found that the thermal effect was catalytically active for the tar cracking at 600⁷00℃.CH₄ was dominantly affected among the secondary pyrolysis gas,indicating that the second reaction dramatically influenced the demethylation.In order to reveal the mechanism of transforming pyrolysis oil into gas,we used the GC×GCTOFMS to analyze thousands of compounds in the pyrolysis oil.Long chain aliphatic amides,nitriles generated CH₄ through demethylation,while ketones produced CO by decarboxylation.更多还原