孔鑫,刘建国,刘意立,赵克,袁进,岳秀萍.基于高压挤压预处理的生活垃圾干湿分离处理工艺不同场景综合效益分析[J].环境科学学报,2020,40(9):3445-3452
基于高压挤压预处理的生活垃圾干湿分离处理工艺不同场景综合效益分析
- Analysis of comprehensive environmental benefits in different municipal solid waste treatment scenarios based on dry-wet fraction separation through high-pressure extrusion pretreatment
- 基金项目：国家自然科学基金项目（No.51908396）；山西省应用基础研究项目（No.201801D221338）；陕西省自然科学基础研究计划（No.2020JQ-374）；宁波市科技计划项目（No.2018B10023）
- 孔鑫
- 1. 太原理工大学环境科学与工程学院, 太原 030024;2. 清华大学环境学院, 北京 100084
- 赵克
- 北京环境工程技术有限公司, 北京 100101
- 袁进
- 太原理工大学环境科学与工程学院, 太原 030024
- 岳秀萍
- 太原理工大学环境科学与工程学院, 太原 030024
- 摘要：目前，生活垃圾分类已经在我国逐渐成为一种"新风尚"，但现阶段以厨余组分为代表的湿垃圾和可燃组分为代表的干垃圾分离效率仍然有限，使得后端生物处理技术难以高效运行，同时也降低了垃圾焚烧厂的能源回收率，这些问题已成为制约我国生活垃圾分类持续推进的瓶颈.本文在前期对高压挤压预处理的研究基础上，利用生命周期清单分析的方法，从温室气体排放、净能源产生、污染物释放、资源回收和垃圾减量等方面，对高压挤压预处理后"湿垃圾厌氧消化+沼渣填埋+干垃圾焚烧发电"、"湿垃圾厌氧消化+沼渣土地利用+干垃圾焚烧发电"和"混合垃圾焚烧"3种处理场景开展对比分析，评估3种场景的综合环境效益，阐明预处理作用与意义.结果表明，处理每吨原生垃圾，两种基于高压挤压预处理的生活垃圾干湿分离处理场景可分别减排温室气体218.84和264.08 kgCO2-Eq，远高于混合垃圾焚烧工艺（169.68 kgCO2-Eq）；在净能源产生方面，两种干湿分离处理场景较混合垃圾焚烧场景约少10%，但同样会削减焚烧过程产生的有毒污染物.此外，利用"湿垃圾厌氧消化产生的沼渣进一步脱水后进行土地利用"这一场景处理每吨生活垃圾，不仅能够实现约160.7 kg的资源回收，而且垃圾整体减量率达到93.4%，是一种适合我国国情的垃圾处理方式.
- Abstract：Nowadays, garbage classification has become a ‘new fashion’ in China. However, at the present stage, the limited separation of wet waste (represented by kitchen waste) and dry waste (represented by combustible waste) resulted in low performance of subsequent biological treatment, as well as low energy recovery rate of waste incineration plant. These problems have become the bottleneck limiting the continuous promotion of garbage classification in China. Based on the previous study of high-pressure extrusion pre-treatment, the present study further comparatively analysed three different scenarios of ‘wet waste anaerobic digestion-dry waste incineration-digestate landfilling’, ‘wet waste anaerobic digestion-dry waste incineration-digestate land-utilization’ and ‘mixed waste incineration’. Specifically, their respective comprehensive environmental benefits were evaluated from aspects of greenhouse gas emission, net energy generation, pollutants releasing, resource recovery and waste reduction using the method of life cycle inventory analysis. This study further clarified the significance and effects of pre-treatment on municipal solid waste treatment in our country. The results showed that two scenarios using high-pressure extrusion could respectively reduce greenhouse gas emission by 218.84 and 264.08 kgCO2-Eq when dealing with one ton raw waste, which was far higher than that of scenario of raw waste incineration (169.68 kgCO2-Eq). For the aspect of net energy generation amount, it was about 10% less in two dry-wet separation scenarios compared with the raw waste incineration scenario, however, fewer toxic pollutants were released in the former two scenarios as well. Furthermore, when one ton raw waste was disposed in scenario of ‘wet waste anaerobic digestion-dry waste incineration-digestate land utilization’, it could not only recover about 160.7 kg fertilizer, but also achieve the entire reduction rate of 93.4%, which is a favourable scenario for waste situation in China.
