上海市试点小区湿垃圾源头减量前后垃圾处理处置全链条碳足迹分析

Full chain carbon footprint analysis of garbage disposal process before and after food waste in-situ reduction treatment in Shanghai pilot communities

上海市于2019年7月率先开始实施垃圾分类工作,湿垃圾的分类与处理是垃圾分类的痛点问题。在小区垃圾分类站,采用食物垃圾粉碎处理器对湿垃圾进行固液分相处理是实现湿垃圾源头减量处理的试点措施。为了进一步探究在不同模式下垃圾源头减量处理前后的碳排放情况,根据联合国气候变化政府间专家委员会(IPCC)制定的《2006年IPCC国家温室气体清单指南》(简称IPCC指南(2006)),并通过生命周期法对上海市普陀区甘泉街道3个试点小区(2365户)进行传统混收混运处理和湿垃圾源头减量2种处理模式下为期1年的对比评估与分析。结果表明,与传统混收混运处理模式相比,湿垃圾源头减量模式处理1 t原生垃圾可多发电7.8 kWh,减少固体清运量0.3 t,减少净碳排放量(CO2)1.57×10-2 t。以上海市垃圾产量2.1×104 t·d-1计,该模式可多发电1.64×105 kWh·d-1,减少固体清运量6300 t,减少净碳排放量330.5 t CO2。基于固液分相的湿垃圾源头减量处理模式,对降低生活垃圾处理处置全链条碳排放具有重要作用。以上研究结果可为我国垃圾分类与处理提供必要的数据支撑。

In July 2019, Shanghai took the lead in implementing garbage classification. The classification and treatment of food waste is a serious problem in garbage sorting. At the garbage sorting station in community,solid-liquid separation for the food waste by the disposer is a pilot measure to achieve the food waste source reduction. In order to further compare the carbon emissions between two different modes, namely, traditional mixed garbage treatment mode and the food waste in-situ reduction treatment mode, 2006 IPCC Guidelines for National Greenhouse Gas Inventories, developed by the United Nations Intergovernmental Panel on Climate Change(IPCC) and life cycle method were used to perform the corresponding assessment and analysis on the data collected from the one-year investigation of pilot communities located in Ganquan Street, Putuo District,Shanghai, with 2 365 households. The results showed that, compared with the traditional mixed garbage treatment mode, the food waste in-situ reduction treatment mode could generate 7.8 kWh more electricity,reduce the solid transportation volume by 0.3 t and the net carbon emissions by 1.4×10-2 t CO2 when treating 1 t raw garbage. According to Shanghai’s daily garbage production of 2.1×104 t, it could generate 1.64×105 kWh more electricity per day, reduce the solid transportation volume by 6 300 t per day and the net carbon emissions by 294 t CO2 per day. The food waste in-situ reduction treatment mode based on solid-liquid separation played an important role in reducing the carbon emissions of domestic garbage treatment and disposal. And the research results would provide necessary data support for the classification and treatment of garbage in China.