摘要
采用氯化铵溶液浸洗生活垃圾焚烧飞灰,以去除Ca(OH)_(2) 和氯化物。然后使用多钨酸钠溶液作为重液对预处理后的飞灰进行密度梯度离心分离,获得不同密度级别的组分。实验重点分析了各密度组分中二噁英的碳含量、化学成分、矿物成分、粒度分布以及绝对I-TEQ浓度。研究发现,碳含量与密度密切相关。随着密度的增加,碳含量从<1.8 g/cm^(3)组分的58.47%降低到>2.7 g/cm^(3)组分的0.29%。化学成分在密度上也有一定程度的差异,密度>2.5 g/cm^(3)组分的粒径明显小于密度<2.5 g/cm^(3)组分的整体粒径。并且发现除<1.8 g/cm^(3)的组分外,每个组分的二噁英浓度都随着密度的增加而降低,这表明碳中存在大量二噁英,其中飞灰本身残留碳的二噁英浓度远大于注入的活性炭。
Ammonium chloride solution was used to leach the municipal solid waste incineration(MSWI)fly ash to remove Ca(OH)_(2) and chlorides.Then,sodium polytungstate solution was used as the heavy liquid to carry out density gradient centrifugal separation on the pretreated fly ash,and components of different density levels were obtained.The experiment focused on analyzing the carbon content,chemical composition,mineral composition,particle size distribution and absolute I-TEQ concentration of dioxins in each density component.It was found that carbon content was well related to density.With the increase of density,carbon content decreased from 58.47%in the<1.8 g/cm^(3)fraction to 0.29%in the>2.7 g/cm^(3)fraction.The chemical composition also varied to some extent in density,with the particle size of components with a density greater than>2.5 g/cm^(3)being significantly smaller than the overall particle size of components with a density less than<2.5 g/cm^(3).And it was found that except for the component with a density of<1.8 g/cm^(3),the concentration of dioxins in each component decreased with increasing density,indicating the presence of a large amount of dioxins in the carbon.The concentration of dioxins in the residual carbon of fly ash itself was much higher than that of injected activated carbon.
作者
李旭
张洪
高通
杨圣超
陆超
刘祥亮
LI Xu;ZHANG Hong;GAO Tong;YANG Shengchao;LU Chao;LIU Xiangliang(China Power Hua Chuang(Suzhou)Electricity Technology Research Company Ltd.,Jiangsu Suzhou 215123;China University of Mining and Technology School of Chemical Engineering,Jiangsu Xuzhou 221116,China)
出处
《广州化工》
2026年第2期126-130,145,共6页
GuangZhou Chemical Industry
关键词
生活垃圾焚烧飞灰
二噁英
碳含量
密度分离
municipal solid waste incineration fly ash
dioxin
carbon content
density separation
