Since municipal wastes contain refuses with high mercury contents, incineration of municipal wastes be- comes the major anthropogenic atmospheric mercury emis- sion source. In China, landfills are however the main way...Since municipal wastes contain refuses with high mercury contents, incineration of municipal wastes be- comes the major anthropogenic atmospheric mercury emis- sion source. In China, landfills are however the main way to dispose of municipal wastes. Total gaseous mercury (TGM) concentrations in landfill gas of Gaoyan sanitary landfill located in suburb of Guiyang City were monitored using a high temporal resolved automated mercury analyzer, and mono-methylmercury (MMHg) and dimethylmercury (DMHg) concentrations in landfill gas were also measured using GC coupled with the cold vapor atomic fluorescence (CVAFS) method. Meanwhile, the TGM exchange fluxes between exposed waste and air and the soil surface of the landfill and air, were measured using low Hg blank quartz flux chamber coupled with high temporal resolved auto- mated mercury analyzer technique. TGM concentrations in landfill gas from half year filling area averaged out at 665.52 ±291.25 ng/m3, which is comparable with TGM concentra- tions from flue gas of a small coal combustion boiler in Gui- yang. The average MMHg and DMHg concentrations aver- aged out at 2.06±1.82 ng/m3 and 9.50±5.18 ng/m3, respec- tively. It is proven that mercury emission is the predominant process at the surfaces of both exposed wastes and soil of landfill. Landfills are not only TGM emission source, but also methylmercury emission source to the ambient air. There are two ways to emit mercury to the air from landfills, one is with the landfill gas through landfill gas duct, and the other through soil/air exchange. The Hg emission processes from landfills are controlled by meteorological parameters.展开更多
文摘Since municipal wastes contain refuses with high mercury contents, incineration of municipal wastes be- comes the major anthropogenic atmospheric mercury emis- sion source. In China, landfills are however the main way to dispose of municipal wastes. Total gaseous mercury (TGM) concentrations in landfill gas of Gaoyan sanitary landfill located in suburb of Guiyang City were monitored using a high temporal resolved automated mercury analyzer, and mono-methylmercury (MMHg) and dimethylmercury (DMHg) concentrations in landfill gas were also measured using GC coupled with the cold vapor atomic fluorescence (CVAFS) method. Meanwhile, the TGM exchange fluxes between exposed waste and air and the soil surface of the landfill and air, were measured using low Hg blank quartz flux chamber coupled with high temporal resolved auto- mated mercury analyzer technique. TGM concentrations in landfill gas from half year filling area averaged out at 665.52 ±291.25 ng/m3, which is comparable with TGM concentra- tions from flue gas of a small coal combustion boiler in Gui- yang. The average MMHg and DMHg concentrations aver- aged out at 2.06±1.82 ng/m3 and 9.50±5.18 ng/m3, respec- tively. It is proven that mercury emission is the predominant process at the surfaces of both exposed wastes and soil of landfill. Landfills are not only TGM emission source, but also methylmercury emission source to the ambient air. There are two ways to emit mercury to the air from landfills, one is with the landfill gas through landfill gas duct, and the other through soil/air exchange. The Hg emission processes from landfills are controlled by meteorological parameters.
