污泥在CO_2气氛下热解CO与CH_4的生成特性  

CO and CH_4 emission characteristics during sewage sludge pyrolysis in CO_2 atmosphere

作　　者：蔡旭[1] 黄群星[1] 王飞[1] 池涌[1] 严建华[1] 

机构地区：[1]浙江大学能源清洁利用国家重点实验室,杭州310027

出　　处：《环境工程学报》2016年第7期3779-3786,共8页Chinese Journal of Environmental Engineering

基　　金：国家重点基础研究发展计划(973)项目(2011CB201506);国家科技支撑计划项目(2012BAB09B03);国家高技术研究发展计划(863)项目(2012AA063505)

摘　　要：利用热重-红外(TG-FTIR)联用技术研究了典型市政污水污泥在CO_2和N_2气氛下的热解特性。基于TG-FTIR分析结果,采用等温模式配合法研究了CO_2气氛下污泥固定床热解过程中CO和CH_4的生成特性,建立了CO和CH_4的生成动力学机理模型,并同传统N_2气氛下污泥热解情况进行了对比,理论模型利用实际实验数据进行了验证分析。结果表明,在实验温度范围内2种气氛下CO与CH_4的生成情况有着比较明显的差异,CO_2气氛下CH_4释放浓度在峰值和总量上都要低于N_2气氛,CH_4释放峰值来得更早,释放时间更为集中,释放过程也结束得更快。相反,CO的释放浓度峰值,总量以及持续时间在CO_2气氛下都要远远高于N_2气氛,随着温度的升高,差距越来越大,CO_2的存在大大促进了CO的生成。经实验验证,理论推导所得的模型公式对于热解产物生成有着良好的预测结果。Pyrolysis characteristics of sewage sludge in a CO_2 and N_2atmosphere were studied using a thermogravimetric analyzer（ TG） coupled with a Fourier transform infrared analyzer（ FTIR）. The TG-FTIR results were fitted with a model to investigate CO and CH_4 emission during sludge pyrolysis in CO_2 and N_2. Kinetic models were developed to estimate the production of CO and CH_4,and the results indicated significantly different generation models of CO and CH_4 in a CO_2 and N_2atmosphere,respectively. The peak concentration and yield of CH_4 emission were lower in CO_2 than that in N_2. The CH_4 emission in CO_2 reached the maximum earlier and was also released more quickly. On the contrary,the peak concentration and yield of CO in CO_2 were much higher than those in N_2,and this difference increased with increasing temperature; the presence of CO_2 was a significant contributor to CO generation. After tests and verifications,the experimental emission data was fitted to theoretical predictions using the kinetic models developed in this report.

关 键 词：污泥 热解 二氧化碳 甲烷 反应动力学 

分 类 号：X705[环境科学与工程—环境工程]