风化淋积型稀土尾矿残留浸取剂演变及稀土迁移模型

The pollution caused by the rare earth ore leaching, in-situ leaching and heap leaching tailings of weathered crust rare earth ore in Longnan Country of Jiangxi Province is put forward in the investigation. Residue leaching agents, and occurrence characteristics and content of rare earth elements were analyzed through a combination of field sampling and laboratory, and traditional and modern analysis methods. Information database of pollutant distribution in different leaching tailings were constructed. By simulating in-situ leaching and heap leaching technology in laboratory, residue leaching agents and the secondary products, as well as the occurrence characteristics and spatial distribution of rare earth elements in different tailings were analyzed. Based on a combination of geostatistics regionalization theory into data mining technique and logarithmic Kriging and triangular mesh interpolation method, the migration and evolution models of residue agents and rare earth elements in different leaching tailings were made up respectively, and the mechanisms were also explored. Based on the Laplace transform and Fourier sine transform theory, Dynamo technology was applied to build a leaching system-chain multiple component transformation models. Leaching changes and evolution model were revealed. And then, scientific basis could be provided for rare earth leaching process improvement and environment governance, and the bottleneck problems of cleaner production and sustainable development of rare earth mining could be also solved.

针对风化壳淋积型稀土矿浸矿引起的污染控制问题，以江西省龙南县足洞风化壳淋积型稀土原地浸矿、堆浸尾矿为研究对象，通过实地采样与实验室模拟，传统与现代分析手段相结合,分析尾矿中残留浸取剂、稀土元素等的赋存特征和含量；构建不同浸矿工艺尾矿中污染物分布信息数据库；通过实验室模拟原地浸矿、堆浸工艺，分析不同浸矿工艺尾矿中残留浸取剂及其次生物、稀土元素的赋存特征及空间分布。基于地统计学区域化变化理论引入数据挖掘技术结合对数克里格与三角网格联合插值法，分别构建不同工艺浸矿尾矿中残留浸取剂、稀土元素的迁移与演化模型。探索不同浸矿工艺尾矿中残留浸取剂、稀土元素的迁移演变机理；基于Laplace变换和Fourier正弦变换理论，引入Ｄynamo技术构建浸矿系统链式多组分迁移转化模型。明确浸矿系统的库流变量关系，揭示迁移与演变规律。为稀土浸矿工艺改进、环境治理提供科学依据，解决稀土开采清洁生产和可持续发展的瓶颈

项目的背景：针对风化壳淋积型矿山原地浸矿、堆浸引起的矿山酸化及沙化环境恶化，导致山体滑坡现象严重，矿区流域氨氮超标，农田土壤酸化和板结，农田废弃；或农田土壤氨氮过剩，导致水稻只开花不结果。.主要研究内容：以江西省龙南县足洞风化壳淋积型稀土原地浸矿、堆浸尾矿等为研究对象，通过现场采样、调查和实验室模拟，明确了原地浸矿、堆浸浸矿工艺尾矿的土壤理化性质；基于地统计学原理，结合数据挖掘技术的克里金插值和网格插值法，构建了稀土元素与残留浸取剂及次生物空间分布模型，并揭示了不同浸矿工艺尾矿中其空间分布规律；基于LAPLace变换、Fourier正玄理论，Dynamo技术构建了浸矿环境系统动力学模型，明确了浸矿系统的库流变量关系，开发了稀土元素含量分析系统软件，揭示了稀土元素和残留稀土浸取剂及其次生物迁移与演变规律，发现了尾矿边坡稳定性、滑坡与浸矿液在矿体中的渗流优先通道相关性。.重要成果、数据及科学意义：开发《尾矿中稀土元素分析系统》软件，对尾矿中稀土元素及赋存形态、含量及空间分布规律的分析结果为稀土矿的有效开发，优化离子型稀土原地浸矿工艺提供了科学的依据；有关尾矿中残留稀土浸取剂及其次生（硝态氮，氨态氮、硫酸根离子）的赋存空间分布规律为尾矿的精准治理提供科学依据；设计发明的砂质型矿山土壤采样器、砂质型矿山动力深层土壤采样器补充了现有土壤采样器对砂质矿山或尾矿库采样器的不足；本项目研究结合原地浸矿布浸矿液注入井的分布，对场地调查方法进行了优化，提出了依据新采样布点法，补充了国家有关现场调查的采样方法；有关尾矿中浸取剂“优先通道”为预判尾矿边坡稳定性、山体滑坡提供科学的依据。