【作者】 陈小威；

【导师】 刘文华；

【作者基本信息】 湖南科技大学 ， 化学工程与技术， 2011， 硕士

【摘要】 人类社会经济的快速发展和工业化的提高,水环境污染越来越严重,尤其是重金属的污染越来越受到人们的重视。本文以湘江株洲段表层水和沉积物为主要研究对象,开展重金属元素的污染研究。沿湘江株洲段共布置了四个地表水的监测断面（枫溪、白石、霞湾、马家河）,八个表层沉积物的采样断面,三个垂直沉积物的采样点。研究探讨了湘江株洲段地表水水质参数:水温、pH、化学需氧量（COD）、生化需氧量（BOD₅）、氨氮（NH₃-N）、总氮（TN）、总磷（TP）的变化规律,以及水环境中重金属元素（Cu、Pb、Zn、Cd、Ni、Cr、Hg、As）的污染状况。研究结果如下:1.以国家《地表水环境质量标准》（GB3838-2002）中的三类作为评价标准,分析四个监测断面水质参数的变化。全年（2010年）pH未超出标准限值,生化需氧量（BOD₅）、总磷（TP）、氨氮（NH₃-N）的浓度均未超出标准限值（BOD₅:4mg/L、TP:0.2 mg/L、NH₃-N:1.0 mg/L）,总氮（TN）的平均值是2.97mg/L。化学需氧量（COD）的变化范围为7.71mg/L～24.03mg/L。霞湾断面、马家河断面个别月份COD值处于国家地表水环境质量标准四类,属于超标的范围。2.原子吸收分光光度法测定地表水中的重金属元素（Cu、Pb、Zn、Cd）含量,以及测定八月份重金属元素的形态分布。重金属元素的含量均未超出国家地表水三类标准限值,其中Cd含量最大值达到0.0041 mg/L,与标准限值的0.005 mg/L接近。在霞湾断面,其各元素溶解态含量的大小为:Cu>Zn>Cd>Pb。3.采集S1～S8共八个表层沉积物样品,待自然风干,用混酸消解的方法处理样品,用原子吸收分光光度法、冷原子吸收法测定样品中的重金属含量。重金属（Cu、Pb、Zn、Cd）含量平均值分别是地球化学背景值的1.71、4.56、4.23、73.52倍;是八十年代湘江均值的1.73、2.25、1.71、1.96倍;是湘江底泥背景值的4.6、6.89、6.85、58.82倍。测定了沉积物样品的pH值,在7.59～8.08之间。4.共采集了三个垂直（柱状）沉积物样品（A1、A2、A3）,A1在老霞湾港下游左岸污染带大约700米的位置,分析垂直沉积物样品重金属含量。Cu、Pb、Zn、Cd的最大值分别出现在0～50cm的深度,分别达到111.69 mg/kg、253.52mg/kg、886.65mg/kg、46.10mg/kg,往下重金属的浓度逐渐下降。Ni、Cr、Hg和As含量的最大值为46.136mg/kg、78.01 mg/kg、1.65mg/kg、116.01mg/kg。采样点A2重金属（Cu、Pb、Zn、Cd、Ni、Cr、Hg、As）含量的平均值分别是:93.92mg/kg、262.85 mg/kg、697.42 mg/kg、35.94 mg/kg、30.14 mg/kg、28.50 mg/kg、1.87 mg/kg、99.22 mg/kg,A3重金属含量的平均值分别是:67.24mg/kg、161.49mg/kg、304.86mg/kg、13.65mg/kg、24.67mg/kg、58.03mg/kg、0.78mg/kg、71.19mg/kg。5.用地质积累指数法和潜在生态风险评价法对重金属的污染程度进行了评价,结果表明:在整个江段Cd的污染最重,潜在生态危害系数的变化范围为901.3～2847.15;污染级别最大,为强-极强、极强污染。两种评价方法的结果基本一致。更多还原

【Abstract】 The rapid economic development of human society and the improvement of industry make the water pollution more and more serious,especially the heavy metal pollution which was paid attention for.The present paper was based on the surface water and sediments of Zhuzhou section of Xiangjiang river and the pollution of heavy metal was carried out.Four monitoring sections （Feng Xi,Bai Shi,Xia Wan,Ma Jia He ） ,eight sections of sampling surface sediments,three sections of sampling vertical sediments were arranged along the Zhuzhou section. The variation of surface water quality parameters （temperature, pH, COD, BOD₅, NH₃-N, TN, TP） and the heavy metals pollution （Cu, Pb, Zn, Cd, Ni, Cr, Hg, As） in water environment in Zhuzhou section were stuied. The results were as follows:1. The variation of surface water quality parameters in four monitoring sections was evuluated by the third Class of the State, "Surface Water Environmental Quality Standard" （GB3838-2002）.The concentrations of BOD₅,TP,NH₃-N and the pH were not attained the state’s standard （BOD₅:4mg/L,TP:0.2 mg/L ,NH₃-N:1.0 mg/L）all the year.The average concentration of TN was 2.97mg/l. The variation of concentration of COD was ranged from 7.71mg/L to 24.03mg/L.The concentration of COD of Xia wan and Ma jiahe was the Fouth Class in months which was excessive.2. The total concentrations of heavy metal（Cu,Pb,Zn,Cd） of surface water was determined by AAS and determined the species of heavy metal in August. The total of concentrations of heavy metal was not attained the state’s third class standard.The maximum of the concentration of Cd was 0.0041mg/l which was close to the standard limit of 0.005 mg / L.The order of concentrations of dissolved heavy metal was the Cu>Zn>Cd>Pb.3. We collected eight surface sediment sampels（S1～S8） to be drying .We determined the total heavy metal By atomic absorption spectrometry and cold vapor atomic absorption with the way of Mixed acid digestion. The total concentrations of heavy metal （Cu,Pb,Zn,Cd） were respectively 1.71,4.56,4.23,73.52 times than the value of geochemical background,and were respectively 1.73,2.25,1.71,1.96 times than the value of eighties in Xiangjiang river,and were respectively 4.6,6.89,6.85,58.82 times than the background value of Xiangjiang river. The pH of sediments were between 7.59～8.08.4. We collected three vertical sediment samples（A1,A2,A3） and determined the concentrations of heavy metal.The A1 was in the left bank of the pollution belt about 700 meters from the Old Xia wan.The maximum of Cu,Pb,Zn,Cd was respectively 111.69mg/kg, 253.52mg/kg, 886.65mg/ kg,46.10mg/kg which appeared respectively at the depth of 0～50cm.The concentrations of heavy metal decreased as the depth reduced. The maximum concentrations of Ni,Cr,Hg,As was respectivly 46.136mg/kg,78.01 mg/kg,1.65mg/kg,116.01mg/kg.The average heavy metal（Cu,Pb, Zn,Cd,Ni,Cr,Hg,As） content of sampling point A2 was 93.92mg/kg,262.85 mg/kg,697.42 mg/kg,35.94 mg/kg,30.14 mg/kg,28.50 mg/kg,1.87 mg/kg ,99.22 mg/kg. The average heavy metal content of sampling point A3 was 67.24mg/kg,161.49mg/kg,304.86mg/kg,13.65mg/kg,24.67mg/ kg, 58.03mg/kg,0.78mg/kg,71.19mg/kg.5. The level of heavy metal pollution was assessed by means of Geo-accumulation Pollution Index and Potencially Ecological Risk Index.The results showed that the pollution of Cd was the most serios,and the variation of index of potencially ecological risk index ranged from 901.3～2847.15. The levels of pollution was strong-very strong,very strong which was the biggest. The results of two evaluation methods are basically the same更多还原