Interaction between an acidic mine water and an agricultural soil material
Interaction between an acidic mine water and an agricultural soil material
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DOI：
10.1016/j.geoderma.2008.10.003
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发表时间：
2008-12
期刊：
影响因子：
6.1
通讯作者：
A. Chen;Chuxia Lin;Wenzhou Lu;Y. Ma;Y. Bai;H. Chen;J. Li
中科院分区：
文献类型：
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作者：
A. Chen;Chuxia Lin;Wenzhou Lu;Y. Ma;Y. Bai;H. Chen;J. Li
通过土柱渗滤试验，研究了酸性矿井水与农业土壤材料之间的相互作用。结果表明，在试验前期，土壤对矿山水载无机酸、Cu、Pb、Zn、Cd有明显的持留作用。约1/3的持留酸仅被土壤物理保持，而其余2/3的持留酸以物理化学或化学方式与土壤胶体结合。随着土柱深度的增加，土壤持酸量有减少的趋势。除了镉，土壤的能力，以消除这些重金属从矿井水持续时间较长，相比，无机酸。与无机酸相反，保留的重金属的浓度随深度增加而增加，这表明这些金属离子的竞争力低于主要的酸性阳离子，如Al 3+，H+和Fe 3+在上层土壤中的可用吸附位点。矿区水体中Cu、Cd、Pb主要以可交换态和氧化物结合态固定，而Zn主要以碳酸盐结合态和有机结合态固定。在矿井水渗透过程中，一些土壤中的金属被动员，并在过滤操作的后期酸性条件下浸出的土壤。与Cu、Pb、Zn和Cd不同，矿山水载Fe主要转化为胶体Fe氧化物/氢氧化物，随水向下流动。很大一部分的矿山水载锰只物理举行，可能不一定在可溶性形式，但在胶体形式。
A column filtering experiment was conducted to investigate interaction between an acidic mine water and an agricultural soil material during percolation of the mine water through the soil column. The results show that the mine water-borne mineral acid, Cu, Pb, Zn and Cd was markedly held by the soil during the earlier stage of the experiment. Approximately 1/3 of the retained acid was only physically held by the soil while the remaining 2/3 of the retained acid was either physiochemically or chemically bound to soil colloids. There was a tendency that the retained acid decreased with increasing depth of the soil column. Except for Cd, the capacity of soil to remove these heavy metals from the mine water persisted longer, compared to mineral acid. In contrast with mineral acid, the concentration of retained heavy metals increased with increasing depth, suggesting that these metal ions are less competitive than major acidic cations such as Al3+, H+and Fe3+for available adsorption sites in the upper soil layers. Mine water-borne Cu, Cd and Pb were immobilized predominantly in exchangeable and oxide-bound forms while mine water-borne Zn was immobilized mainly in carbonate- and organic-bound forms. During mine water infiltration, some soil-borne metals were mobilized and leached out of the soil under acidic conditions during the latter stage of filtration operations. Unlike Cu, Pb, Zn and Cd, mine water-borne Fe was transformed into colloidal Fe oxides/hydroxides which were carried by the downflowing water. A large proportion of mine water-borne Mn was only physically held, probably not necessarily in soluble forms but in colloidal forms.