摘要
随着生活垃圾焚烧处理方式的不断推广,焚烧飞灰的产生量也不断增加。按照我国固体废物分类方法,焚烧飞灰属于危险废物,必须进一步处置才能进入填埋场或资源化利用。本文分析了飞灰物理化学特性,论述了常规处置技术(水泥固化、化学药剂稳定化、酸溶剂提取和熔融固化等)存在的问题。将原始飞灰直接应用于水泥、混凝土或路基材料,飞灰中高含量的重金属和盐类会产生新的环境问题。飞灰水洗可以高效去除其中的可溶性盐类,水洗飞灰在焙烧后重金属的浸出浓度远低于原始飞灰烧结后的相应浓度,飞灰水洗-焙烧技术具有很好的应用前景。
In China, incineration becomes more and more popular to treat municipal solid waste, during which a lot of fly ash is generated. As hazardous waste, fly ash needs further treatment before landfill or reuse. This paper analyzes the physical and chemical characteristics of fly ash and discusses the issues from conventional treatment process including cement stabilization, chemicals stabilization, acidic solvent extraction and melting. When fly ash is directly used for cement production, concrete and road pavements, it will cause new environmental issues due to heavy metals and salts that fly ash contains. Water-washing can remove most of the soluble salts and the concentrations of heavy metals in leachate from baked water-washed fly ash will be much lower than that from baked original fly ash. The technology of washing-and-baking has a good promising prospect for fly ash utilization.
出处
《四川环境》
2008年第1期61-65,共5页
Sichuan Environment
关键词
垃圾
焚烧飞灰
重金属
资源化
浸出
MSW
incineration fly ash
heavy metals
utilization
leachate
