垃圾填埋场大气汞的浓度和形态

Mercury Concentration and Species in the Atmosphere at Landfills

对贵阳市和武汉市的5座城市生活垃圾填埋场大气中的ρ(气态总汞)进行了测定,并分析了填埋场的大气活性气态汞、颗粒态汞、单甲基汞和二甲基汞的质量浓度分布.结果表明:5座填埋场ρ(气态总汞)为1.6～473.7 ng/m3,不同采样点的平均值为8.5～155.7 ng/m3,最高值出现在填埋场的工作面及工作面下风向区域;而封闭填埋场或运行填埋场的覆土区的ρ(气态总汞)较低.天气条件和垃圾处理活动均可影响ρ(气态总汞)水平.贵阳高雁垃圾填埋场大气ρ(活性气态汞),ρ(颗粒态汞),ρ(单甲基汞)和ρ(二甲基汞)的平均值分别为37.4,255.3,12.4和12.7 pg/m3.虽然不同形态汞的质量浓度明显高于全球背景值,但其产生的环境风险不大.

Total gaseous mercury in the atmosphere was measured at five solid waste landfills in Guiyang and Wuhan City. In addition, mass concentration distribution of reactive gaseous mercury, total particulate mercury, monomethyl and dimethyl mercury were determined at one of the landfills. The range of mass concentration of total gaseous mercury at the five landfills was from 1.6 to 473.7 ng/m^3 , with averages at different sites ranging from 8.5 to 155.7 ng/m^3 . The highest values occurred at the working face area and the downwind area, while the lowest values appeared at the closed landfill or the paved part of the operational landfill. Total gaseous mercury mass concentration was affected by the weather conditions, as well as the waste treatment activities. The mean values of reactive gaseous mercury, total particulate mercury, monomethyl and dimethyl mercury measured at Gaoyan landfill were 37.4, 255.3, 12.4 and 12.7 pg/m^3 , respectively. Although the mass concentrations of different mercury species in the atmosphere at these landfills were obviously higher than the global background mass concentration, they produced little environmental risk.