城市污水污泥焚烧处理环境影响分析

以城市污水污泥为研究对象，应用生命周期评价方法分别对干化焚烧、污泥与煤混燃发电、污泥与生活垃圾掺烧发电3种焚烧处理方式的生命过程进行清单分析，以获得各处理方式的能耗及其对环境的影响.结果表明，处理1.0 t湿污泥，填埋处理的能耗和总环境负荷均最低，分别为2.24kg （以标准煤计）和46.55×10-3标准人当量(PET).污泥直接干化处理能源消耗最大，达到了111.12 kg（以标准煤计）.污泥与垃圾或者与煤掺烧发电由于利用固体废弃物化学内能，降低了化石燃料消耗.这两种掺烧处理方式的环境排放都以酸化和富营养化为主，对局地性的影响占据首位，因此，污泥焚烧处理仍需加强尾气净化设备的投入，以减少酸性气体及二噁英的排放.

Environmental impact assessment of sewage sludge incineration treatments

Life cycle inventories of sewage sludge during traditional landfill handling and three incineration treatment processes (drying-incineration treatment, co-combustion with coal and co-incineration with municipal solid waste for electricity generation) were collected and analyzed by means of LCA (life cycle analysis) to determine the energy consumption and environmental effects. Landfill handling has the lowest energy consumption (2.24 kg standard coal) and total environment impact loading (46.55×10-3, PET) for 1.0 t wet sludge. Drying-incineration treatment requires the largest energy consumption, about 111.12 kg standard coal. Due to the recovery of the internal chemical energy of sewage sludge, the consumption of fossil fuel is decreased by co-incineration with municipal solid waste or with coal. The environmental emissions during these two co-incineration processes are mainly acids and nutrients, which play a significant role in the local regional impact. Therefore, flue gas purification during the sludge incineration process still needs to be emphasized, so as to further decrease the acid gas and dioxin emissions.