Remediation of PCB-contaminated soil using a combination of mechanochemical method and thermal desorption.
The combination of mechanochemical method and thermal desorption for remediating polychlorinated biphenyls (PCBs) in contaminated soil was tested in this study. The effects of grinding time and heating time on PCB removal efficiency were investigated. The contaminated soil, mixed with CaO powder at a weight ratio of 1:1, was first ground using a planetary ball mill. After 4 h of grinding, the total PCB concentration and its toxic equivalence quantity (TEQ) decreased by 74.6 and 75.8%, respectively. Then, after being heated at 500 °C for 60 min, the residual PCBs in mechanochemical + thermal treated soil decreased to 247 ng/g, resulting in a removal efficiency of 99.95%. The removal effect can be promoted by longer grinding time and heating time; however, increased energy consumption was inevitable. The combination of grinding time and heating time should be optimized in a practical remediation process.
State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
Zhong-Hua
ZH
Zhao
State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China. lixd@zju.edu.cn.
Xiao-Dong
XD
Li
State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
Ming-Jiang
MJ
Ni
State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
Tong
T
Chen
State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
Jian-Hua
JH
Yan
D052918:Environmental Restoration and Remediation / Q000379:methods*; D006358:Hot Temperature; D011078:Polychlorinated Biphenyls / Q000302:isolation & purification*; D012987:Soil; D012989:Soil Pollutants / Q000302:isolation & purification*
D012987:Soil; D012989:Soil Pollutants; D011078:Polychlorinated Biphenyls
Combination; Mechanochemical method; PCBs; Removal efficiency; Thermal desorption