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以者海铅锌中和渣和水淬渣为研究对象,利用原子吸收和原子荧光分光光度法测定其重金属(As、Pb、Cu、Zn、Cd、Cr)的含量,采用BCR连续提取法研究了重金属元素的形态分布特征,利用单因子污染指数法、潜在生态风险评价指数法和风险评价编码法对该铅锌渣中重金属的超标水平及生态风险进行评价。结果表明:(1)参考土壤环境质量三级标准,中和渣中的Cd、Zn、Cu超标倍数分别为215、20.6和4.65,水淬渣中的Cd、Zn、As超标倍数分别为11.51、8.62和3.075,中和渣中Cd、Zn、Cu和水淬渣中Cd、Zn污染程度较严重,水淬渣中的As也存在轻度污染性,对生态环境存在威胁。(2)中和渣中Pb、Zn及Cr的主要形态为可还原态,Cd和Cu的主要赋存形态为弱酸提取态,As的残渣态所占比例最大;水淬渣中的Pb、Cd、Cr、As主要赋存于残渣态,Cu和Zn的主要形态分别为可氧化态和可还原态。(3)潜在生态风险评价结果表明,中和渣中Cd和Zn分别处于很高和高生态风险等级,水淬渣中Cd处于偏高生态风险,其他几种重金属则表现为低生态风险。铅锌渣RI值介于183.81~5357.58,为中等-严重生态风险,Cd的风险贡献率最高。(4)风险评价编码法研究表明,中和渣中Cd和Cu分别处于极高和高风险级、Cr和As处于中等风险级;水淬渣中Cd、Zn、As均处于中等风险级,其他重金属处于低风险级,并且中和渣和水淬渣的RAC值顺序为Cd>Cu>Cr>As>Zn>Pb和Zn>As>Cd>Cr>Cu>Pb。
The content of heavy metals (As, Pb, Cu, Zn, Cd, Cr) in sea-lead-zinc neutral slag and water quenched slag was studied by atomic absorption spectrometry and atomic fluorescence spectrometry. The BCR continuous extraction method The morphological distribution characteristics of heavy metal elements were determined. The single factor pollution index method, the potential ecological risk index and the risk assessment coding method were used to evaluate the levels of heavy metals and the ecological risk in this lead-zinc slag. The results showed as follows: (1) With reference to the third grade soil environmental quality standard, the over-standard times of Cd, Zn and Cu in neutralization residue were 215, 20.6 and 4.65 respectively, and the over-standard times of Cd, Zn and As in water- 8.62 and 3.075. Cd, Zn and Cu in the neutralized slag and Cd and Zn in the water quenched slag are more seriously polluted, and As in the water quenched slag is also slightly polluted, which poses a threat to the ecological environment. (2) The main forms of Pb, Zn and Cr in the neutralization slag are reducible, while the main storage forms of Cd and Cu are weak acid extractables, and As is the largest proportion of As; the contents of Pb, Cd , Cr, As mainly in the residual state, the main forms of Cu and Zn were oxidizable and reducible. (3) The results of potential ecological risk assessment showed that Cd and Zn in middle-residue were at very high and high ecological risk level respectively, while Cd in water-quenched residue was at high ecological risk while other heavy metals showed low ecological risk. The RI value of lead-zinc slag ranged from 183.81 to 5357.58, which was intermediate-serious ecological risk, with the highest risk contribution rate of Cd. (4) According to the risk assessment coding method, Cd and Cu in the neutralization residue are at extremely high and high risk levels, while Cr and As are at intermediate risk levels. Cd, Zn and As in the water-quenching residue are at intermediate risk level, while others The heavy metals were at a low risk level, and the order of RAC values for neutralized slag and water quenched slag was Cd> Cu> Cr> As> Zn> Pb and Zn> As> Cd> Cr> Cu> Pb.