淋滤试验中酸与重金属析出及镉有效态分布规律研究

设计了淋滤试验，探讨了酸与重金属的变化规律，并对试验试体分层取样，采取Tessier连续提取法进行了镉各种有效态测试，讨论了镉元素的在淋滤试验中的迁移特征。试验结果表明，土层可以抑制酸和重金属的向水相迁移；镉在试体中主要以残渣态存在于各层中，可交换态含量较高；镉可交换态含量呈现在中间层较高的现象；土壤中的残渣态镉含量及镉总含量均比废石略低。由于Cd的可交换态含量较高。并有可能因毛细作用向上迁移，复垦中应采取提高土壤PH、施加有机肥或调节土壤中锌的含量等措施，以抑制镉向植物中的迁移。

Research on ARD and Speciation of Heavy Metals in Leaching Test of Waste Rock in Copper Mines

In this paper, soil and waste rock samples are taken from Dexing copper mine. And Leaching experiment has been carried out for 6 months. Then, samples are taken from 5 layers and sequential extraction procedure developed by Tessier et al. is adopted to analyze the chemical speciation of cadmium in different soils and waste rock samples in the experiment. The results show that soil covering has the ability of restraining the release of acid and heavy metals. Cadmium in soils is dominated in the mineral species and exchangeable species in all layers. Fe-Mn oxides species and the carbonates species, organic matter species cannot be detected by the equipment. The amount of exchangeable cadmium is the highest in middle soil layer. The amount of mineral cadmium in soil layers is lower than that in waster rock layers. The exchangeable cadmium enrichment in middle soil layer may be the result of eluviation and capillarity. The enrichment should be controlled in waste rock piles reclamation.