Transfer mechanisms of contaminants in cement-based stabilized/solidified wastes.
Stabilization/solidification (S/S) processes are routinely used for the final treatment of hazardous wastes prior to land disposal. Cement-based binder systems with partial replacement of cement by pulverized fuel ash (PFA) are common. In order to predict the long-term leaching characteristics of S/S wastes, it is important to understand the leaching mechanism. This paper presents experimental results from a study that has investigated the leaching behaviour of contaminants from cement-based S/S waste forms. A novel radial leach test (RLT) has been used to study the migration of heavy metals. The results show that contaminants migrate from the inner core of the S/S waste during leaching to the sample surface and accumulate near the edge of the S/S waste. The degree of accumulation is related to the contaminant species and the Ca(OH)2 content.
Qiao
X C
XC
Key Laboratory of Silicate Materials Science and Engineering, Wuhan, University of Technology, 122 Luoshi Road, Wuhan, HuBei 430070, China. xcqiao2003@163.com
Poon
C S
CS
Cheeseman
C R
CR
D003252:Construction Materials; D006256:Hazardous Waste; D019216:Metals, Heavy; D018505:Waste Management
D006256:Hazardous Waste; D019216:Metals, Heavy