垃圾焚烧炉飞灰熔融处理前后的重金属分布特性

Partition of Heavy Metals for the Fly Ashes from MSW Incinerator Before and After Melting Treatment

研究探讨了熔融温度、熔融时间、碱基度对飞灰熔融处理前后重金属分布特性的影响．结果表明,熔融温度为1 200℃时Ni、Cr、Cu、As的固溶率最高,除Zn外,熔融温度对Pb、Cd、Hg挥发率影响较小．随熔融时间的增加,Ni、Cr、Cu、As的固溶率在90 min后趋于稳定,Pb、Cd、Hg的挥发率在30 min内达95％以上,接近完全挥发;碱基度较高有利于重金属Ni、Cu、As、Cr的固溶,碱基度变化对Pb、Cd、Hg的挥发率影响较小,低碱基度对Zn的挥发影响较为显著．

The influence of fly ash on partition characteristics of heavy metals before and after melting treatment was studied, including the melting temperature, melting time and the basicity. Experimental results indicate that the fixation rates of Ni, Cr, Cu and As reach the maximum at 1 200 ℃. With the exception of Zn, temperature changes have little impact on the volatilization rates of Pb, Cd and Hg. With the increase of melting time, the fixation rates of Ni, Cr, Cu and As in samples tend to level off after melting for 90 min. The volatilization rates of Pb, Cd, Hg are more than 95% and nearly reach complete volatilization in 30 rain. High basicity is beneficial to the fixation of Ni, Cr, Cu and As. The changes in the basicity of fly ash exert little influence on volatilization of Pb, Cd, Hg and Zn. Low basicity has remarkable effect on volatilization of Zn.