Remediation of in-situ Leach Mining Contaminated Soil by Amendment-plant Synergism

This study aimed to remediate in-situ leach mining contaminated soil by amendment-plant synergism. The results showed that plant species exhibited ex-tremely significant effects on the concentration of nitrate nitrogen; to be specific, the concentration of nitrate nitrogen in soil planted with wheat was reduced from 692.19 mg/kg to lower than 100 mg/kg; when the mass ratio of amendment to soil reached 3：50 and the amendment particle size was 1-2 mm, the concentration of nitrate ni-trogen in soil planted with wheat was reduced to 43 mg/kg. The amendment type exhibited extremely significant effects on the concentration of ammonium nitrogen; to be specific, when the mass ratio of amendment to soil reached 10：50, the concen-tration of ammonium nitrogen in soil added with 2-3 mm zeolite was reduced from 23 593.75 to 3 300 mg/kg on day 15. Amendments and plants mainly exhibited desorption performance for sulfate radical in soil, and the amendment type extreme-ly significantly affected the concentration of sulfate radical; to be specific, the con-centration of sulfate radical in soil added with limestone increased from 370 mg/kg to 900 mg/kg on day 7.

Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching

The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

稀土矿山水系中Pb、Cd、Cu、Zn的化学形态及其迁移研究

对南方稀土矿山水系环境中Ｐｂ、Ｃｄ、Ｃｕ、Ｚｎ的化学形态进行研究，探讨４种重金属在此水系中的迁移转化规律。结果表明，ＮＨ＋４的存在容易引起ＣＵ、Ｚｎ、Ｃｄ再生污染，不利于Ｃｕ、Ｚｎ、Ｃｄ从水相向固相转化，而Ｐｂ受影响较小。

离子型稀土原地浸析采矿的再吸附问题及对策

指出了离子吸附型稀土矿原地浸析采矿过程中稀土离子再吸附现象，探讨了浸析过程中稀土离子的解吸与再吸附机理，分析了原地浸析采场稀土离子再吸附产生的原因和不恰当的注液方法对原地浸析采矿的影响，并介绍了解决浸析过程中稀土离子再吸附问题的对策．

原地浸析采矿方法在离子型稀土矿的应用及其展望

离子吸附型稀土矿是我国70年代初发现的一种宝贵稀土资源。本文概述了其成矿与富集规律及其开采方式由露采池浸工艺发展为原地浸析采矿的演变过程，介绍了露天池浸与原地浸析采矿两种方法的工艺流程及其优缺点，目前原地浸析采矿方法在离子型稀土矿山的应用简况及今后研究发展的方向．

香根草在离子型稀土堆浸矿场的修复应用研究

采用香根草对离子型稀土堆浸矿场开展修复试验,研究香根草对土壤中氨氮、总氮及重金属的去除效果,及香根草茎叶和根系对稀土元素的富集能力。结果显示,在0.5和1 m深土壤中,氨氮、总氮均显著降低;对重金属Se,Sb去除率在95%以上,Pb去除率在50%~70%之间,Cd去除率在32%~45%之间;香根草根部和茎叶对稀土元素均有富集作用,随时间推移,香根草生物量显著增加,根系对稀土元素富集能力增加,茎叶对稀土元素富集能力降低;其中Y含量最高,其次是Ce,La,Nd。通过Pearson相关性分析,可知氨氮、总氮和重金属元素间具有协同作用。