不同污泥处理与处置工艺的碳排放分析

Analysis on Carbon Emission from Different Sewage Sludge Treatment and Disposal Processes

对我国现行的主流污泥处理与处置技术路线:生物干化/土地利用工艺和热干化/焚烧工艺的碳排放进行了计算和收支分析。结果表明,生物干化工艺的CO2直接排放量和碳足迹量均较低,而热干化/焚烧工艺的CO2排放量和碳足迹量分别为生物干化的5.33和4.94倍。将干化污泥用作草坪基质具有一定的碳减排和碳汇增加功能,CO2减排量和吸收量分别达到68.7和648kg/t。从碳净排放量看,热干化/焚烧工艺表现为高碳排放特征(372.9 kg/t),而生物干化/土地利用工艺具有碳减排效应(-643.6 kg/t),符合当前的政策背景与产业导向。

The current technology roadmaps of sewage sludge treatment and disposal in China are bio-drying/land utilization process and heat drying/incineration process. Carbon dioxide emission from the processes was calculated and its emission budget was analyzed. The results indicate that the carbon dioxide emission and carbon footprint of bio-drying/land utilization process are lower, and those of heat drying/incineration process are 5.33 and 4.94 times those of bio-drying/land utilization process respec- tively. Using dried sludge as lawn substrate can reduce carbon emission and increase carbon sequestra-tion, and the amounts of carbon dioxide emission reduction and absouption are 68.7 kg/t and 648 kg/t respectively. Considering net carbon emission, the heat drying/incineration process is characterized by high carbon emission of 372.9 kg/t, while the bio-drying/land utilization process has carbon emission reduction effect （ -643.6 kg/t）. The later meets the current policy and the future trend.