煤灰对城市生活垃圾焚烧飞灰的熔融玻璃化特性影响  

Effect of coal ash on melting and vitrification characteristics of municipal solid waste incineration fly ash

作　　者：王镛翔 赵伟 郭金霞[1] 赵鹏龙 黄戒介[1] 张永奇 WANG Yongxiang;ZHAO Wei;GUO Jinxia;ZHAO Penglong;HUANG Jiejie;ZHANG Yongqi(State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,Shanxi Province,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001 [2]中国科学院大学,北京100049

出　　处：《化学工程》2024年第9期1-7,共7页Chemical Engineering(China)

基　　金：中央引导地方科技发展资金资助项目(YDZJSX2021C040)。

摘　　要：垃圾焚烧飞灰中因含有重金属、二噁英等有害物质需无害化处理。选取高硅铝含量的煤灰作为添加剂,开展飞灰与煤灰共熔融实验,研究煤灰对飞灰熔融特性和矿物质组成变化特性的影响,并利用FactSage模拟矿物相变化。结果表明:添加煤灰可以有效改善飞灰的熔融特性,添加质量分数为40%时,混合灰的流动温度达到最低值1 192℃。随着熔融温度升高,产物中复杂矿物成分逐渐演化为结构稳定的矿物相,并且随着煤灰质量分数的增加,产物中主要矿物相从钙铝黄长石向透辉石、蓝方石、钙长石依次转变,实验结果与热力学模拟的变化规律基本一致。当温度达到1 300℃且煤灰质量分数在20%—50%时,混合灰能够玻璃化,其中重金属Cd、Cu、Zn、Pb大部分挥发到气相中,Cr、Ni则基本被固定在玻璃体中。玻璃体浸出实验表明,玻璃体中重金属Cr、Cd、Ni、Cu、Zn、Pb的浸出质量浓度远低于国家标准,实现了飞灰的无害化处理。MSWI(municipal solid waste incineration)fly ash contains harmful substances such as heavy metals and dioxins,which requires harmless treatment.High-silica-alumina content coal ash was chosen as an additive to conduct co-melting experiments with fly ash,the effect of coal ash on melting characteristics and mineral composition changes of MSWI fly ash was studied,and FactSage was utilized to simulate mineral phase changes.The results show that adding coal ash can effectively improve the melting characteristics of MSWI fly ash,with the lowest flow temperature of the mixed ash reaching 1192℃when the addition mass fraction is 40%.As the melting temperature increases,the complex mineral components in the products gradually evolve into structurally stable mineral phases.Moreover,with the increase of coal ash mass fraction,the main mineral phases in the products change from gehlenite to diopside,hauyne,and anorthite in turn.The experimental results are consistent with the changing rules of thermodynamic simulation.When the temperature reaches 1300℃and the mass fraction of coal ash is between 20%-50%,the mixed ash can be vitrified,with most of the heavy metals Cd,Cu,Zn,and Pb volatilizing into the gas phase,while Cr and Ni are mainly fixed in the glass.Leaching experiments on the glass show that the leaching mass concentrations of heavy metals Cr,Cd,Ni,Cu,Zn and Pb are much lower than the national standards,achieving the harmless treatment of fly ash.

关 键 词：生活垃圾焚烧飞灰 煤灰 熔融 玻璃化 

分 类 号：X705[环境科学与工程—环境工程]