[Comparison of fixation effects of heavy metals between cement rotary kiln co-processing and cement solidification/stabilization].
Both cement rotary kiln co-processing hazardous wastes and cement solidification/stabilization could dispose heavy metals by fixation. Different fixation mechanisms lead to different fixation effects. The same amount of heavy metal compounds containing As, Cd, Cr, Cu, Pb, Zn were treated by the two kinds of fixation technologies. GB leaching test, TCLP tests and sequential extraction procedures were employed to compare the fixation effects of two fixation technologies. The leached concentration and chemical species distribution of heavy metals in two grounded mortar samples were analyzed and the fixation effects of two kinds of technologies to different heavy metals were compared. The results show the fixation effect of cement rotary kiln co-processing technology is better than cement solidification/stabilization technology to As, Pb, Zn. Calcinations in cement rotary kiln and then hydration help As, Pb, Zn contained in hazardous wastes transform to more steady chemical species and effectively dispose these heavy metals compounds. Cr3+ is liable to be converted to much more toxic and more mobile Cr6+ state in cement rotary kiln. And so Cr wastes are more fit for treatment by cement solidification/stabilization technology. The work could provide a basis when choosing disposal technologies for different heavy metals and be helpful to improve the application and development of cement rotary kiln co-processing hazardous wastes.
Zhang
Jun-li
JL
Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China. zhangjl03@mails.tsinghua.edu.cn
Liu
Jian-guo
JG
Li
Cheng
C
Jin
Yi-ying
YY
Nie
Yong-feng
YF
D004784:Environmental Monitoring / Q000379:methods; D004787:Environmental Pollution / Q000032:analysis / Q000517:prevention & control; D006256:Hazardous Waste / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods*; D015203:Reproducibility of Results; D017640:Silicates / Q000032:analysis* / Q000737:chemistry
D006256:Hazardous Waste; D019216:Metals, Heavy; D017640:Silicates