Investigation On The Characteristics Of Chloride In Landfill Leachate And Study Of Its Migration And Transformation

In the wake of developments in the world ecnomy,the population and the urbanization,our human demand for water continues to increase In rencent years.At the same time,the population of the water environment gradually increases on account of our life and production.Directly related to the human health,the problem of the groundwater pollution is the focus of the research on water environment.The recently studies have shown that landfill leachate had became one of the important source of groundwater pollution.And the degree of pollution will continue to increase as the aging of equipment in landfill and the failure of anti-seepage measure.Among the numerous pollutant in the leachate,chlorinated organic vompounds have the high detection rate and the strong toxicity.In the latest standard of the drinking wanter in China,the control of chlorinated organic compounds increased 31 species than the old standard.We can say that the existence of chlorinated organic compounds is directly related to the safety of our drinking wanter.In fact,we have detected a variety of chlorinated organic compounds including hexachlorobenzene in the investigation on groundwater surrounded the landfill.So,preventing its pollution to the groundwanter is imminent.Therefore,it is important for us to carry out chlorinated organic compounds' kinds,concentration and the rule of its migration and transformation.The major work of the paper may be summarized as the followings: summarizing the kinds and concentration of chlorinated organic compounds based on the results of previous studies;choseing hexachlorobenzene as the target pollutant;setting up simulation experiment about the landfill to explore the migration and transformation of hexachlorobenzene;using analysis software to carry out the relationship between the water quality of leachate and the migration and transformation of hexachlorobenzene.Conclusions can be obtained:(1)The author through the literature survey,discovered the kinds of chlorinated organic compounds can be roughly divided into chlorinated paraffin,chlorinated olefin and chlorinated aromatic hydrocarbons.(2)Using three dimensional fluorescence spectrum technology,the factor analysis,and principal component analysis.,we separated out of three components C1,C2 and C3.Based on previous research,we could determine the C1 and C2 as ptotein,C3 as humic substances according to the emission wavelength and excitation wavelength.Using principal component analysis,we got two main ingredients F1 and F2.F1 is mainly pritein and F2 is humic substances.Then,we analyze that when 7 to 21 days,samples is given priority to F1 and when 28 days,samples is given priority to F2.So,about a month later,humic substances became to dominate in the samples.(3)The degradation of hexachlorobenzene can be mainly divide into two ways.Firstly,hexachlorobenzene degrades to pentachlorobenzene;Then,one way along 1,2,3,5-tetrachlorobenzene to 1,3,5-trichlorobenzene to 1,3-Dichlorobenzene;another way along 1,2,4,5-tetrachlorobenzene to 1,2,4-trichlorobenzene to 1,4-dichlorobenzene.(4)The significant correlation between hexachlorobenzene,1,2,3,5-tetrachlorobenzen with HIX has shown that the degree of humification will benefit to the degradation of hexachlorobenzene and 1,2,3,5-tetrachlorobenzen.Both1,2,3,5-tetrachlorobenzen and 1,2,4,5-tetrachlorobenzene have significant correlation to pentachlorobenzene.It is consistent with both of them are the main degradation products of pentachlorobenzene.In addition,the degree of humification inhibit the degradation of 1,2,4-trichlorobenzene.