贫细杂硼镁铁矿资源选冶过程多元矿物组分选择性分离与强化机制研究

The key of high efficiency and cleaning utilization of ludwigite resource is improving the recovery of valuable component doped in ludwigite. However, the unclear understanding of the special nature of ludwigite, the insufficient rules based on the special nature of ludwigite, and the incomplete theories on enhanced migration and effective separation, in mining and metallurgical process of ludwigite, hinder the improvement of technology on separation and extraction in production practice of ludwigite located in Liaoning, with a low grade, minisize and impure status, the fundamental work on the key scientific issues above will be conducted by combined measurement of theoretical analysis and experimental research, and using the micro and the macro-scale experimental methods. It includes three aspects, one is high efficiency separation and control theory of iron, boron micro fine minerals in a view of surface/interface, second is phase structure evolution and enhanced migration in metallurgical separation process, the third is the mechanism of external field in mineral surface/interface and the joint enhanced mechanism. Through the work above, the phase structure evolution, transmission and chemical reaction rules in complex multiphase system, the updating and transformation behavior of the surface/interface, ordered coupling and enhanced separation mechanism in multi-component and multi-field, will be revealed, which is benefit to propose a new enhanced method on improving the recovery of valuable component doped in ludwigite and provide a scientific base for high efficiency and cleaning utilization of born and iron resources in a intergrown and associated status.

硼镁铁矿资源高效利用的核心问题是有价组元回收率低，强化迁移规律和有效分离理论不完整，对资源特点与清洁高效利用之间的规律认识不足，阻碍了有价组元高效清洁分离提取及生产实践中的技术进步。本项目针对辽宁地区硼镁铁矿资源贫、细、杂的特点，以提高硼、铁有价组元回收率为目标，围绕选冶过程有价组元选择性分离提取与过程强化的关键科学问题，采用理论分析与实验研究相结合的研究方法，开展从微观到宏观尺度的铁、硼微细粒矿物高效分选的表/界面控制与分离理论、冶金分离过程有价组元矿相转变与强化迁移规律、外场对矿物表/界面作用机理与反应过程协同强化机制的基础研究，阐明多相复杂体系中有价组元矿相结构演变规律、相间传输与化学反应规律、有价矿物表/界面更新与转变行为，揭示多场多组元间有序耦合及强化分离机制，探索旨在提高硼镁铁矿有价组元利用率的过程强化新方法，为我国硼、铁等共伴生资源的清洁高效利用奠定科学基础。

辽宁地区硼镁铁矿是一种典型的硼、铁等共伴生资源，储量2.8亿吨，综合利用价值极高，但“贫、杂、细”的资源特点使其在选冶过程中硼、铁等有价组元回收率较低，目前已成为该资源开发利用的瓶颈问题。基于此，本项目立足于硼镁铁矿的矿物组成特点及研究现状，以提高硼、铁有价组元回收率为目标，提出微波强化辅助硼镁铁矿磨选，含硼铁精矿富氢短流程还原和硼精矿机械活化强化组元高效分离工艺，阐明了铁、硼微细粒矿物高效分选的表/界面控制与分离理论，揭示了冶金分离过程有价组元矿相转变与强化迁移规律，明确了外场对矿物表/界面作用机理与反应过程协同强化机制。主要结论包括：（1）高功率短时间内的微波加热更利于硼铁矿的辅助磨矿，微波处理的矿样其磨矿产品中粒度小于74μm的百分含量较原矿磨矿产品提高18.22%。经微波加热处理的矿石在磁选后，其回收产品的品位较原矿（48.56%）提高了3%-10%，铁元素回收率达到了85.83%，提高了28.23%。（2）经1170℃焙烧20min的含硼铁精矿氧化球团抗压强度为2696.3N，满足还原所需的强度要求。1000℃富氢还原30min后球团还原度为96.84%。1500℃熔分60min时，富硼渣和含硼生铁分离效果较好，含硼生铁TFe的含量为91.59%，铁的回收率为96.32%，可以作为优质的炼钢原料；富硼渣中B2O3含量为17.25%，硼的回收率为93.57%，其活性为87.34%，可以作为生产硼砂或硼酸的原料。（3）硼精矿机械活化过程中球磨参数会影响硼精矿的物理化学性质。机械活化过程中机械力越强，作用时间越长，机械活化效果越明显。机械活化使矿石表/界面性质发生改变，提高了硼精矿粉体对乙醇和水的润湿性，增大了矿石表面自由能，并增强了矿石在液体中的分散性。常压碱浸后，两阶段机械活化更有利于提高硼精矿B2O3活性，干磨20min后湿磨10min的硼精矿样品B2O3活性为89.2%，干磨40min后湿磨20min的硼精矿样品B2O3活性可达91.9%。