研究了生活-农业混合型垃圾焚烧飞灰与单一生活垃圾焚烧飞灰(简称混合型飞灰与单一型飞灰)热处理过程中的重金属挥发特性与稳定化效果,并结合FT-IR、XRD检测手段对稳定化机理进行了探讨。结果表明,单一型飞灰中重金属的挥发性普遍高于混合型飞灰,垃圾源氯含量对重金属的挥发性有明显影响。飞灰中Mn、Cr不易挥发,Zn、Cu较易挥发,Pb、Cd挥发性很强,热处理温度超过1 000℃时挥发率都超过50%。800℃为相对最优的热处理温度,兼顾了热处理过程重金属稳定化与抑制挥发。800℃以上时飞灰形成了稳定的硅酸盐结构体系,是重金属热处理后难以浸出的主要机理。
The volatility and the stabilization of heavy metals in flyash in municipality agriculture mixed waste incineration( Type A) and municipal solid waste incineration( Type B) were investigated. And the heavy metals stabilization mechanism was studied by using FT-IR and XRD. The results indicate that the volatility of heavy metals is higher in type B than that in type A,and is significantly affected by the content of chloride in waste source. The volatility of heavy metals in fly ash varies in a sequence of Mn,Cr Zn,Cu Pb,Cd. More than 50% of Pb and Cd are volatilized when the temperature exceeds 1 000 ℃. The relatively optimal thermal treatment temperature is 800 ℃ and the heavy metals stabilization is higher and the evaporation rate is lower. The primary mechanism of heavy metals stabilization is the formation of stable silicate structure system above 800 ℃.