高硫煤矸石协同飞灰制备多孔玻璃物相转变机理  

Mechanism of phase transformation in the preparation of porous glass from high-sulfur coal gangue and fly ash

作　　者：许晨阳 龙孟卓[1,2] 曹建尉 王志[1] 常雅丽[1,2] XU Chenyang;LONG Mengzhuo;CAO Jianwei;WANG Zhi;CHANG Yali(Key Laboratory of Green Process Engineering,National Engineering Research Center for Green Recycling of Strategic Metal Resources,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;School of Mechanical and Electrical Engineering,China University of Mining&Technology-Beijing,Beijing 100037,China)

机构地区：[1]中国科学院过程工程研究所,战略金属资源绿色循环利用国家工程研究中心,中科院绿色过程工程重点实验室,北京100190 [2]中国矿业大学(北京)机械与电气工程学院,北京100083

出　　处：《矿冶》2024年第4期579-586,共8页Mining And Metallurgy

基　　金：河北省重点研发计划项目(21373808D)。

摘　　要：采用高硫煤矸石协同垃圾焚烧飞灰制备多孔玻璃,同时利用玻璃体固定垃圾焚烧飞灰中的Pb、Cd、Zn、Cr、Cu、Mn等重金属,实现多源固废、危废协同无害化处置和资源化利用。针对多孔玻璃轻质和高强度难以兼顾的问题,一方面,通过还原气氛抑制残碳在中低温氧化反应,使高硫煤矸石中残碳在1000℃以上与Fe_(2)O_(3)反应生成CO_(2)气体,促进熔体发泡,多孔玻璃容重由900 kg/m^(3)降低至300 kg/m^(3);另一方面,通过在配合料中添加高岭土,使多孔玻璃孔壁的主要晶相由长石转变为莫来石,莫来石独特的交联结构使多孔玻璃具有较高强度。当容重在500 kg/m^(3)时,多孔玻璃强度提升了80%。多孔玻璃重金属浸出毒性分析结果表明,各种重金属的浸出浓度远远低于规定的标准限值(5.0 mg/L),多孔玻璃中重金属Pb的浸出浓度降低至1.1×10^(-2)mg/L,其它重金属的浸出浓度也普遍呈现出显著的下降趋势,说明多孔玻璃对多元重金属具有良好的固定效果。High-sulfur coal gangue is used as the primary raw material,and in conjunction with municipal solid waste incineration(MSWI)fly ash,porous glass has been produced.The process not only immobilizes heavy metals such as Pb,Cd,Zn,Cr,Cu,and Mn found in the MSWI fly ash but also achieves the harmless disposal and resource utilization of multiple solid and hazardous wastes.This study employs two strategies address the challenge of balancing lightweight and high strength in porous glass.Firstly,by adjusting the atmosphere to create a weakly reducing environment,the premature reaction of residual carbon is hindered,allowing the residual carbon in the high-sulfur coal gangue to react with Fe_(2)O_(3)at temperatures above 1000℃to generate CO_(2)gas.Thereby the foaming of the melt can be promoted,reducing the bulk density of the porous glass from 900 kg/m^(3)to 300 kg/m^(3).Secondly,by adding kaolin to the raw material mixture,the primary crystalline phase of the porous glass walls shifts from feldspar to mullite.The unique interlocking structure of mullite crystals imparts higher strength,enhancing the strength of the porous glass by 80%when the bulk density is at 500 kg/m^(3).Toxicity leaching tests on the porous glass indicate that the leaching concentrations of various heavy metals are far below the specified standards(5.0 mg/L).The leaching concentration of Pb in the porous glass is reduced to 1.1×10^(-2)mg/L,and the concentrations of other heavy metals also show a significant downward trend.The results show that porous glass has a good fixation effect on multi-element heavy metals.

关 键 词：高硫煤矸石 垃圾焚烧飞灰 莫来石 相变 重金属 

分 类 号：X75[环境科学与工程—环境工程] TD98[矿业工程—选矿] TF01[冶金工程—冶金物理化学] TB32[一般工业技术—材料科学与工程] TB34