摘要
利用激光粒度仪、X射线衍射、扫描电镜等对华南某垃圾焚烧厂不同粒径焚烧飞灰(原灰)矿物相组成和微观形貌进行分析,同时研究其重金属浸出毒性和形态特征。结果表明:焚烧飞灰颗粒均在2mm以下,<38μm粒径占比达到68.07%;微观结构差异较大,多为不规则的疏松结构。焚烧飞灰主要化学成分为CaO、Na2O和K2O,CaO较多集中在大颗粒飞灰中,而K2O和Na2O在小粒径焚烧飞灰中含量更高;主要矿物相为氯化物和含钙矿物,含量随粒径减小而增加。焚烧飞灰重金属浸出毒性较低,仅Cr浸出浓度超出GB16889—2008生活垃圾填埋场污染控制标准的限值。在不同粒径范围内,Cr酸提取态含量较高,占总量的16.61%~23.60%,形态较不稳定。Cd和Cu可还原态比例较高,存在一定的浸出风险。Ni、Pb、As和Ba等金属残渣态所占比例较高,重金属形态较稳定。
The mineral phase composition and microstructure of fly ash(raw ash)with different particle sizes in a waste incineration plant in south China were analyzed by means of laser particle size analyzer,X-ray diffraction and scanning electron microscope.Meanwhile,the leaching toxicity and morphological characteristics of heavy metals were studied.The results showed that the incinerated fly ash particles were all less than 2 mm,and the particle size less than 38μm accounted for 68.07%.The difference of its microstructure was large,which mostly irregular loose structure.The main chemical constituents of incinerated fly ash were CaO,Na2O and K2O.CaO was mostly concentrated in large-particle fly ash,while K2O and Na2O were more abundant in small-particle fly ash.The main mineral phases were chloride and calcium-containing minerals,and the content increased with the decrease of particle size.The heavy metal leaching toxicity of incinerated fly ash was relatively low,only Cr leaching concentration exceeded the limit of Standard for Pollution Control on the Landfill Site of Municipal Solid Waste(GB 16889-2008).In the range of different particle sizes,the acid extractable content of Cr was higher,accounting for 16.61%~23.60%of the total,and the morphology was more unstable.The proportion of reducing state of Cr and Cu was higher,which had some leaching risk.The residual fraction content of Ni,Pb,As,Ba and other metals accounted for a higher proportion,and the forms of them were stable.
作者
陈清
汪屈峰
李艳
史力争
黄沅清
朱锋
海景
谢颖诗
Chen Qing;Wang Qufeng;Li Yan;Shi Lizheng;Huang Yuanqing;Zhu Feng;Hai Jing;Xie Yingshi(GZ Environmental Protection Investment Group Co.Ltd.,Guangzhou Guangdong 510330;South China Institute of Environmental Science.MEE,Guangzhou Guangdong 510535)
出处
《环境卫生工程》
2019年第4期13-18,共6页
Environmental Sanitation Engineering
基金
国家自然科学基金项目(51608223)
关键词
生活垃圾焚烧飞灰
矿物
重金属
形态分布
浸出毒性
MSW incinerated fly ash
mineral
heavy metal
species distribution
leaching toxicity
