[Pathways of mercury emissions to atmosphere from closed municipal landfills].
Using the automated mercury vapor analyzer and dynamic flux chamber (DFC) method, the pathways of mercury emissions to atmosphere were measured at a closed landfill in Wuhan, China. The results show that the mainly pathway is by the surface cover, and emissions from vent pipes is negligible. Average Hg fluxes during the observation period was (192.5 +/- 245.3) ng x (m2 x h)(-1), which was 1 - 2 orders of magnitude greater than that from background zone. Hg flux exhibited a clearly diurnal pattern, reaching the maximum near midday and the lowest during night. Solar radiation was the environmental factor that has highest relationship with Hg flux, with coefficient of 0.77, this indicated that photo-reduction of Hg(II) being a prominent process in the production of volatile elemental mercury (Hg(0)). Mercury concentrations in landfill gas (LFG) at different vent pipes averaged from 7.0 - 68.9 ng x m(-3), which was much lower than that of operational landfills, and the flow rate of landfill gas was very slow.
Li
Zhong-Gen
ZG
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
Feng
Xin-Bin
XB
Tang
Shun-Lin
SL
Wang
Shao-Feng
SF
D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere / Q000032:analysis*; D002681:China; D002947:Cities; D008628:Mercury / Q000032:analysis*; D012037:Refuse Disposal / Q000379:methods*
D000393:Air Pollutants; D008628:Mercury