垃圾填埋场渗滤液中的汞及现场污水处理设施对其的去除

渗滤液一直是困扰垃圾填埋场的一个主要问题,处理不当会对周围生态环境造成严重的污染。垃圾中混入的汞淋滤进入渗滤液将会造成水体的汞污染。对贵阳市高雁垃圾卫生填埋场产生的渗滤液原液和不同处理单元过程中汞的含量进行了调查分析,结果表明该填埋场渗滤液原液中的汞含量为79.4ng·L-1,处于国内外的中低水平,就汞而言污染并不严重。经过处理,渗滤液有近2/3的汞被去除了。渗滤液原液中的汞主要以颗粒态为主,随着处理单元过程,这一比例逐渐降低。渗滤液中的汞含量与填埋垃圾汞含量、pH、以及填埋物质对汞的吸附有关。

MERCURY IN LANDFILL LEACHATE AND ITS REMOVAL BY THE ON-SITE SEWAGE TREATMENT PLANT

Leachate is regarded as one of the significant aspects to land filling operations concerning its environmental impacts, which will arouse serious pollution to surrounding environment if not properly treated. In this study, we sampled and analyzed Hg in the raw leachate and the leachate in different cells of the on-site leachate treatment plant at Gaoyan Sanitary Landfill, Guiyang, China. The results showed that Hg was relatively low in the raw leachate (0.0794 μg·L~(-1)) when compared to most landfill leachates in the world (0.05~160 μg·L~(-1)), and suggested Hg contamination was not severe indeed. After being treated, mercury in the leachate was removed by over two thirds. The majority of the species of mercury in the raw leachate was associated with particulates, and their percentage decreased gradually with the process in the treatment plant. Hg concentrations in the leachate highly depend on the mercury contents in urban solid wastes, pH, and adsorption on waste materials.