风化壳淋积型稀土矿开发的现状及展望

Prospect and Development of Weathered Crust Elution-Deposited Rare Earth Ore

风化壳淋积型稀土矿是中重稀土的主要来源,它的开发一直受到稀土工业的极大关注。评述了风化壳淋积型稀土矿的成矿原因、矿床特征、稀土矿物在矿体垂直剖面中的组成和分布,以及矿石含水的多样性、酸碱缓冲性、吸附离子的稳定性和吸附离子的可交换性等理化性质。阐述了稀土离子在风化体系中的迁移富集规律和所形成的稀土配分特征。介绍了池浸、堆浸和原地浸出三代浸取工艺演化过程的科技进步,探讨了稀土浸出机制及浸出过程的强化,比较了几种浸取剂的浸取效果,简述了前两代工艺留下的采矿区和堆场区的植被恢复与土壤修复。结合原地浸出工艺的生产实际,提出了今后开发风化壳淋积型稀土矿的发展方向。

The weathered crust elution-deposited rare earth ores are the principal sources of medium and heavy rare earth, and its development has being closely noticed by the industry of rare earth. In this paper, the metallogenic causes, characteristics of mineral deposits, and the composition and distribution of rare earth minerals in the vertical section of ore bodies were discussed. The diversity of water content in ores, the buffer of acid and alkali, the stability of adsorbed ions, and the exchangeability of adsorbed ions were also discussed in this paper, which showed the rules of the migration and concentration of rare earth ions in weathering systems and the characteristics of rare earth distribution. This paper, moreover, introduced the technological progress in the evolution process of the third-generation leaching process of pool leaching, heap leaching and in-situ leaching. It described the leaching mechanism and the enhancing of leaching process, comparing the leaching effects of several leaching agents. Vegetation restoration and soil restoration in mining and storage areas left by the previous two generations of technology were briefly described. Finally, the directions of developing the weathered crust elution-deposited rare earth ores, combined with the production practice of in-situ leaching process, were suggested.