The Pollution Analysis Of Heavy Metals And Its Risk Evaluation In Liao River

ABSTRACT:The research of this essay is focused on petrochemical and chemical industries、Dongzhou River、Hun River, Taizi River, Shen-Fu Irrigation in Liao River. The pollution characteristics of heavy metal in water, suspended solid and surface sediments had been analysed. Index of geo-accumulation and potential ecological risk of heavy metals in surface sediment was assessed by the method of potential ecological risk index.This research shows the rule of adsorption about the heavy metal.Those provides scientific basis for the control and treatment of Rivers. The followings are conclusions:(1) Distribution characteristics of13kinds of heavy metals in water during three seasons and suspended solids and surface sediment of petrochemical and chemical industries, Cr、Cd、Pb、Hg, As were better than Grade Ⅰ,and in some sections Cu、 Zn was worse than Grade V.Ba, Se、Ni、Co、Fe were better than Grade V。In NO2Oil industry there were significant accumulations of Cd、Se、Co、Ba、Pb、Hg、 Ni in surface sediments,Cr、Co、As、Zn didnt have any accumulation. In Acrylic fiber industry there were significant accumulations of Cd、Se、Co、Hg、Ba、Zn、Hg、Ni in surface sediments,Cr、Co、As、Pb didnt have any accumulation. In Qingyang Chemical industry there were significant accumulations of Cd、Se、Cu、Hg、Ba、Pb、 Ni in surface sediments, Cr、Co、As、Zn didnt have any accumulation.(2) Distribution characteristics of13kinds of heavy metals in water and suspended solids of Dongzhou River in flood periods and non-flood periods were studied. Cr、Cd、 Hg、As、Se were better than Grade I all the times. Pb、Cp、Ba、Al、Ni、Co、Fe、 Zn were almost better than Grade V. There were significant accumulations of Cd、Hg、 Se、Pb、Co、Zn、Ba、Cu、As in suspended solids,Cr、Zn、Ni、Co、Pb didnt have any accumulation.(3) In Hun River Cr、Cd、Hg、As、Se were better than Grade I all the times. Pb、 Cu，Ba、Al、Ni、Co、Fe、Zn were almost better than Grade V.There were significant accumulations of Se、Cd、Hg、Al、Ni、Ba in suspended solids, Cr、Co、Zn、Pb didnt have any accumulation.(4) In Taizi River Cr、Cd、Hg、As、Se were better than Grade I all the times. Pb、 Cu、Ba、Al、Ni、Co、Fe、Zn were almost better than Grade V.There were significant accumulations of Cu、Ba、Hg、Cd、Se、Ni、As、Cu、Ba in suspended solids,Cr、 Cr, Co didnt have any accumulation. (5) Distribution characteristics of13kinds of heavy metals in surface sediments. There were significant accumulations of Ba、Pb、Cu Co、Ni、As、Hg、Cd、Se、Cu in surface sediments, Cr、Zn、Sb didnt have any accumulation.(6)Use BCR sequential extraction method Determination heavy metals of surface sediments in Shenfu irrigation area. Cd、As were almost based In exchangeable and carbonate-bound. Cd、As were almost based In exchangeable and carbonate-bound. Pb were almost based In Fe-Mn oxides. Ni were almost based In Organic and sulfide bound. Cr、Cu were almost based In Residual. Results indicated:Igeo classify are between0-3, and the contamination levels are from non to middle, and potential ecological risk of heavy metals in sediment exhibits light to middle, with Cd as priority risk. Various heavy metals pollution degree from high to low is:Zn>As>Pb>Cu>Cr>Cd. Cd>Cu>Pb>Se>Hg. Individual potential ecological risk factor in descending order of heavy metals is Cd>Hg>Cu>Pb>As>Cr.