Investigation of the leaching behavior of lead in stabilized/solidified waste using a two-year semi-dynamic leaching test.
Long-term leaching behavior of contaminant from stabilization/solidification (S/S) treated waste stays unclear. For the purpose of studying long-term leaching behavior and leaching mechanism of lead from cement stabilized soil under different pH environment, semi-dynamic leaching test was extended to two years to investigate leaching behaviors of S/S treated lead contaminated soil. Effectiveness of S/S treatment in different scenarios was evaluated by leachability index (LX) and effective diffusion coefficient (De). In addition, the long-term leaching mechanism was investigated at different leaching periods. Results showed that no significant difference was observed among the values of the cumulative release of Pb, Deand LX in weakly alkaline and weakly acidic environment (pH value varied from 5.00 to 10.00), and all the controlling leaching mechanisms of the samples immersed in weakly alkaline and weakly acidic environments turned out to be diffusion. Strong acid environment would significantly affect the leaching behavior and leaching mechanism of lead from S/S monolith. The two-year variation of Deappeared to be time dependent, and Devalues increased after the 210thday in weakly alkaline and weakly acidic environment.
Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, 430071, Bayi Road, Wuchang District, Wuhan, Hubei Province, China. Electronic address: qiangx@whrsm.ac.cn.
Qiang
Q
Xue
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China.
Ping
P
Wang
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China.
Jiang-Shan
JS
Li
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China.
Ting-Ting
TT
Zhang
ARC Centre of Excellence for Geotechnical Science and Engineering, The University of Newcastle Callaghan, NSW, 2308, Australia.
Shan-Yong
SY
Wang
D000143:Acids / Q000737:chemistry*; D003252:Construction Materials; D004058:Diffusion; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000737:chemistry*; D015233:Models, Statistical; D012037:Refuse Disposal / Q000379:methods*; D012987:Soil; D012989:Soil Pollutants / Q000737:chemistry*; D013997:Time Factors
D000143:Acids; D012987:Soil; D012989:Soil Pollutants; D007854:Lead
Diffusion; Leaching mechanism; Lead; Long-term; Stabilization/solidification