Destruction of DDT wastes in two preheater/precalciner cement kilns in China.
The destruction of DDT formulations and DDT contaminated soil was conducted by feeding wastes into the flue gas chamber at the kiln inlet of two different preheater/precalciner cement kilns in China. The concentration of DDT, PCDD/PCDFs and HCB were measured in the flue gas of the main stack, in the solid material under baseline conditions and when feeding DDT-wastes. The destruction efficiency and the destruction and removal efficiency for DDT were in the range of 99.9335%-99.9998% and 99.9984%-99.9999%, respectively. The emissions of PCDD/PCDFs and HCB in the flue gas varied in the range of 0.0019-0.0171 ng I-TEQ/Nm(3) and 0.0064-0.0404 μg/Nm(3), respectively. The emission factor for PCDD/PCDF and HCB varied from 0.0137 to 0.0281 μg/ton and from 17.32 to 109.34 μg/ton of clinker, respectively. The concentration of PCDD/PCDFs and HCB in solid samples decreased as follows: cement kiln dust, 4.1-5 ng I-TEQ/kg and 0.70-0.71 μg/kg, respectively; >raw meal, 0.82-0.97 ng I-TEQ/kg and 0.18 μg/kg, respectively; >cement clinker, 0.09-0.22 ng I-TEQ/kg and 0.14-0.18 μg/kg, respectively. This study indicates that the feeding of DDT and POPs-wastes to the lower temperature part of a cement kiln system possibly to create a buildup of trace not-destroyed compounds in the system and might cause emissions; the technical feasibility and the environmental acceptability of this practice need to be investigated thoroughly.
Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Dahai
D
Yan
Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing 100035, China. Electronic address: peng.zheng@mepfeco.org.cn.
Zheng
Z
Peng
Foundation for Scientific and Industrial Research (SINTEF), PO Box 124, N-0314 Oslo, Norway.
Kåre Helge
KH
Karstensen
Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Qiong
Q
Ding
Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Kaixiang
K
Wang
Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Zuguang
Z
Wang
D002681:China; D003634:DDT / Q000032:analysis / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D017745:Incineration; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*
D012989:Soil Pollutants; D003634:DDT
Cement kiln; DRE/DE; Emission factors; POPs