基于“双碳”目标下污泥处置方式碳排放量分析——以广州市为例

Analysis of carbon emissions of sludge disposal methods based on the"dual carbon"target——Taking Guangzhou as an example

通过分析广州市城镇污水、污泥产量及各处置方式城镇污泥量,并针对土地利用、建材利用、焚烧利用和卫生填埋等4种不同处置方式,计算污泥处置过程中的碳排放量,依据往年数据,构建多元回归模型,预测未来广州市碳排放量。结果表明,截至2020年底,广州市共有污水处理厂63座,处理能力为774万m^(3)/d,城市污泥年产生量为104.78万t(含水率为80%,下同),处置方式主要以建材利用和焚烧发电为主,二氧化碳当量约为1690.97×10^(6) kg CO_(2-eq),以黄浦、白云和荔湾区排放最多。同时,预测2030年广州市城镇污泥产量将达到2059.05万t,与此同时二氧化碳当量将达到34134.48×10^(6) kg CO_(2-eq),较2020年增长1918.63%,因此为了“双碳”目标的实现,必须继续优化城镇污泥的处置方式。

By analyzing the output of urban sewage and sludge in Guangzhou and the amount of urban sludge by different disposal methods,the carbon emissions in the sludge disposal process are calculated for four different disposal methods including land use,building material utilization,incineration and sanitary landfilling.Based on the data from previous years,a multiple regression model to predict future carbon emissions in Guangzhou is constructed.There are 63 sewage treatment plants in Guangzhou at the end of 2020,with a treatment capacity of 7.74 million m3/d,and an annual urban sludge production of 1.0478 million tons(with a moisture content of 80%,the same below).The main disposal methods are building materials utilization and incineration for power generation.The emission of greenhouse gas is about 1690.97×10^(6) kg CO_(2-eq),with the most emissions in Huangpu District,Baiyun District and Liwan District.It is predicted that the output of urban sludge in Guangzhou in 2030 will reach 20,590,500 tons.In addition,carbon emissions will reach 34134.48×10^(6) kg CO_(2-eq),increasing of 1918.63%compared to 2020.Therefore,in order to achieve the"dual carbon"goal,it is necessary to optimize the disposal of urban sludge.