基于分类的张家港市生活垃圾典型处置情景环境效益分析

为系统揭示生活垃圾分类和末端处置匹配对全过程管理环境效益的改善，按照张家港市日均生活垃圾产量1850 t计，基于生命周期评价方法和实测垃圾组分数据，通过测算污染物排放的直接总环境影响潜值和电能回收量折算后的总环境影响潜值，分析和预测了垃圾分类典型情况和不同末端处置能力匹配情景下的张家港市生活垃圾处置环境效益.垃圾分类后厨余垃圾的平均厨余组分质量占比（厨余垃圾纯度，95%）较未分类小区（66%）提高了29个百分点，其他垃圾中的厨余组分质量占比（41%）则降低了25个百分点.末端处置能力现状情景下，厨余垃圾分出量为150 t·d^-1时，直接总环境影响潜值随厨余垃圾纯度提高逐渐降低，较垃圾未分类时（3.41×10^-10，以PET₂₀₀₀计，下同）减少约10%；厨余垃圾分出量大于150 t·d^-1时，厨余垃圾分出量和纯度不断提高，分流厨余垃圾的填埋处置将导致污染排放增多，直接总环境影响潜值逐渐增加.生活垃圾处置环境效益的提升不仅依靠分类效果的改善，也依靠末端处置能力的匹配.末端处置能力规划情景下，生活垃圾分类后直接总环境影响潜值（1.73×10^-10~2.40×10^-10）均低于末端处置能力现状情景.厨余垃圾处置能力充足，相同厨余垃圾纯度下，直接总环境影响潜值随厨余垃圾分出量增加而降低.末端处置能力现状情景下电能回收量折算后的总环境影响潜值为-0.89×10^-10~-0.39×10^-10，高于末端处置能力规划情景（-2.13×10^-10~-1.82×10^-10）.结果表明，末端处置能力按规划扩建后，垃圾分类效果持续提升利于提高全过程管理的环境效益.从全过程角度协同提升垃圾分类效果与末端处置能力匹配程度，能有力改善环境效益.

Environmental Benefit Analysis of Municipal Solid Waste Typical Disposal Scenarios in Zhangjiagang City Based on Classification

The aim of this investigation was to reveal the municipal solid waste (MSW) environmental benefit improvement when MSW classification and terminal disposal matched from the perspective of MSW integrated management. According to the average daily MSW production of 1850 t in Zhangjiagang City, by calculating the direct total environmental impact potential converted from the pollutant emission (DTEIP) and the total environmental impact potential after the conversion of power recovery, the environmental benefit of MSW disposal under scenarios in which the typical MSW classification procedure matched with various terminal disposal capabilities were analyzed and predicted based on the life cycle assessment (LCA) method and MSW composition data collected from Zhangjiagang City. The average proportion of food components in food waste (purity of food waste, 95%) increased by 29 percentage points after MSW classification, compared with that of unclassified communities (66%), whereas the average proportion of food components in residual waste (41%) decreased by 25 percentage points. Under the scenarios based on the current situation of terminal disposal, when the food waste separation amount was 150 t·d^-1, the DTEIP would gradually decrease with the increase in food waste purity, which decreased by approximately 10% compared with that of the unclassified scenario (3.41×10^-10 in PET₂₀₀₀; the same applies hereinafter). When the food waste separation amount was above 150 t·d^-1, as the separation amount and purity of food waste gradually increased, the disposal of separated food waste by landfill would lead to increasing pollution. The improvement of the environmental benefit of MSW disposal depended not only on the improvement of the MSW classification efficiency but also on the matching degree with the terminal disposal capacity. Under the scenarios based on the terminal disposal plan, the DTEIP (1.73×10^-10-2.40×10^-10) was lower than that of the current terminal disposal scenarios after MSW classification. When the food waste disposal capacity was sufficient, and the purity of food waste remained stable, the DTEIP decreased as the food waste separation amount increased. The total environmental impact potential after the conversion of power recovery in the scenarios based on the current situation of terminal disposal was -0.89×10^-10- -0.39×10^-10, which was higher than that in the scenarios based on the current situation of terminal disposal (-2.13×10^-10- -1.82×10^-10). The results indicated that the continuous improvement of the MSW classification effect greatly promoted the environmental benefit from MSW integrated management after the terminal disposal capacity expanded according to the plan. Synergistically promoting the matching degree of the MSW classification effect and terminal disposal capability can significantly optimize environmental benefits from the perspective of MSW integrated management.