垃圾焚烧飞灰熔融渣特性分析

研究了熔融固化产物--熔融渣的特性.结果表明:熔融渣的主要成分为CaO,Al₂O₃和SiO₂,其含量占总质量的99%左右,而SO₃,K₂O,Na₂O和Cl在熔融渣中的含量明显降低,其质量分数分别从原始飞灰中的10.74%,8 58%,3.81%和20.59%降低到0.17%,0.04%,0.23%和0.11%;熔融渣中碱性氧化物和酸性氧化物的含量基本相同,碱度接近于1.0;重金属Cr和Zn的固定率较高,分别为94.2%和81 7%,而Cu,Pb和Cd的固定率较低,分别为31.4%,14.5%和24.6%;采用美国TCLP方法测试的熔融渣中重金属浸出量均低于国家危险废物浸出毒性鉴别标准限值. 

Characteristics of Melting Slag of Fly Ash from Municipal Solid Waste Incinerator

The properties of melted slag,which is the product of melting and solidification,were studied.The experimental results show that main compositions of melted slag,i.e.CaO,Al_2O_3 and SiO_2,account for 99% of the total mass,but the mass fractions of SO_3,K_2O,Na_2O and Cl elements decrease from initial 10.74%,8.58%,3.81% and 20.59% to final 0.17%,0.04%,0.23% and 0.11%,respectively.In melted slags,alkaline oxide content is basically similar to that of acidity oxide,and the alkalinity is close to 1;the fixed rate of heavy metals Cr and Zn are higher(94.2% and 81.7%),but those of Cu,Pb and Cd are lower,which are 31.4%,14.5% and 24.6%,respectively.The TCLP was conducted to study the heavy metal leachate concentrations,and the results showed that the leachate contents were lower than the regulatory thresholds of the standard of hazardous waste toxic identification.