生活垃圾分类处理方式的生态效率评价

中国生活垃圾产量大、增速快,若处理方式不当会给环境和社会带来巨大危害,近年来提倡的垃圾分类处理方式是垃圾减量化的关键一环.综合考虑垃圾处理对环境、能源、经济和社会四方面影响,构建适用于垃圾处理的3E+S生态效率评价模型.将垃圾源头分类、末端分类处理方式纳入垃圾处理生命周期中构建4种生活垃圾处理情景.结果表明,混合收运+末端分类的处理情景具有潜在最优生态效率,分类收运+焚烧的处理情景由于源头分类、收运环节更为复杂导致其总环境影响潜值最大,且生命周期成本最高.对比考虑或不考虑社会成本计算得到的生态效率表明,社会成本的加入显著影响生态效率.源头分类是影响生活垃圾分类处理生态效率的敏感性因素,通过降低垃圾源头分类单元过程多余的环境排放和成本或推广使用以末端机械化分类（PGAS）技术为代表的低污染低成本的垃圾分类新技术,都能够提高垃圾处理的生态效率.

Eco-efficiency assessment of municipal solid waste sorting treatment mode

The production of China's municipal solid waste (MSW) is large and grows rapidly. If not handled properly, it will bring great harm to our environment and society. In recent years, the waste sorting treatment mode advocated by government is a key link of waste reduction. The "3E+S" evaluation model of eco-efficiency was established by comprehensively considering the impact of waste treatment on environment, energy, economy and society. Four kinds of waste treatment scenarios were constructed by integrating the waste source sorting and terminal sorting into the life cycle of waste treatment. The results showed that S3 (mixed collection and transportation + terminal sorting) had the potential optimal eco-efficiency, while S2 (source sorting and transportation + incineration) had the largest potential environmental impact and the highest life cycle cost due to the more complex of the process of source sorting and transportation. Moreover, the sensitivity analysis of source sorting on the eco-efficiency showed that source sorting was indeed an important factor affecting the environmental and economic performance of waste treatment. Reducing redundant unit process on source sorting of waste or promoting the use of terminal sorting technology (PGAS) which was as a representative to the new waste sorting technology of low pollution and low cost, can improve the eco-efficiency of waste treatment.