生活垃圾焚烧飞灰在饰面砖中资源化应用技术

REUSE OF MSWI FLY ASH IN MAKING OF GLAZED TILE

分析了飞灰的性质,利用飞灰、红泥及缸砂研制饰面砖,研究了飞灰对饰面砖性能及微观结构的影响,并对其安全性进行了评价。结果表明:飞灰主要化学成分是CaO、SiO2、Al2O3,构成SiO2-Al22O3-金属氧化物体系,可用作饰面砖的原材料;当飞灰掺加量为20%时,饰面砖表现出良好的性能:抗压强度19·2MPa,吸水率7·2%,表观质量达到一等品要求;与飞灰相比,饰面砖中重金属浸出能力大大降低:As、Pb、Ni、Cr、Cu、Hg、Cd水平振荡浸出毒性未检测出,Zn的水平振荡浸出值下降到飞灰中的0·014倍,Hg、Cd有效浸出毒性未检测出,As、Pb、Ni、Cr、Cu、Zn的有效浸出毒性分别下降到飞灰中的0·056、0·001、0·067、0·058、0·056、0·029倍。

MSWI fly ash was used to make glazed tile based on analysis of its characterization,together with red argil and cylinder sand.Besides,influence of fly ash on performance and microstructure of glazed tile as well as its environmental risk were studied.It is found that major chemical constitution of fly ash is CaO,SiO_2 and Al_2O_3,featuring an SiO_2-Al_2O_3-metal oxides system,which can be used as the raw material of glazed tile.When 20% fly ash is used,glazed tile presents nice performances:compression strength being 19.2 MPa,water-absorption rate being 7.2%,presentation quality standing in the grade one category.In addition,leaching,in accordance with the HVEP standard,from glazed tile,of As,Pb,Ni,Cr,Cu,Hg and Cd can't be detected,and that of Zn is reduced to 1.4%,in comparison with fly ash.While,leaching,in accordance with the ALT standard,from glazed tile,of As,Pb,Ni,Cr,Cu and Zn is reduced respectively to 5.6%,0.1%,6.7%,5.8%,5.6% and 2.9%,compared with fly ash,and that of Hg and Cd can't be detected.