配料对焚烧飞灰电弧炉熔渣晶化行为的影响

摘要

将垃圾焚烧飞灰电弧炉熔融处理后的液态熔渣直接浇铸成型后热处理,运用同步热分析仪、X射线衍射仪和扫描电镜等方法,研究废玻璃和晶核剂(TiO2和Cr2O3)等辅助原料的添加对微晶玻璃晶化行为及性能影响.研究表明,适量掺加废玻璃对微晶玻璃理化性能有显著改善,晶核剂类型及添加比对微晶玻璃主晶相和晶化程度影响较大,微晶玻璃的理想原料配比为m(废玻璃)∶m(垃圾焚烧飞灰)=1∶1,晶核剂TiO2添加质量分数为3％,制成的微晶玻璃主晶相为透辉石Ca( Mg,Al)( Si,Al) 2O6和少量普通辉石Ca( Mg,Fe,Al)( Si,Al)2O6,抗弯强度54.96 MPa,主要理化性能达到或优于天然花岗岩和大理石,重金属浸出浓度低于国际建材环保要求限值.%To deal with the issue of municipal solid waste incineration fly ash, an ash melting treatment technology in combination with electric arc furnace metallurgical processes, was developed. The crystallization behavior of arc-melting slag form waste incineration fly ash was examined by differential thermal analysis ( DTA ) , X-ray diffractometry (XRD) , and scanning electron microscopy ( SEM). Effects of additive waste glass cullet and nucleating agent on the crystallization behaviour, physical mechanical, and chemical characteristics were investigated. The results show that adding appropriate amount of waste glass will significantly improve the properties of glass-ceramics. The type and add ratio of nucleating agent have a greater impact on its crystallization behavior. The ideal raw material for glass formula is: mixed waste glass and waste incineration fly ash at 1: 1 ratio with nucleating agent of TiO2 added at 3%. The glass-ceramics with main crystalline phase of Ca( Mg, Al) (Si, A1)2O6 and Ca( Mg, Fe, Al) (Si, A1)2O6 has bending strength of 54.96 Mpa. The physical mechanical and chemical characteristics are equivalent or superior to natural materials such as granite and marble. The leaching concentration of heavy metals is below environmentally regulatory thresholds of overseas building materials.