高钒钛低品位磁铁矿表观还原动力学与复杂反应界面关系实验验证

As it is shown that the reduction regular pattern of Liaoxi high-vanadium-titanium low-grade magnetite is greatly different from that of ordinary vanadium-titanium magnetite from preliminary laboratory experimental results, it is guessed that the overall reaction rate and reaction interface (“reaction zone”) should be commonly controlled by the reaction interface of multiple oxides involving in the reduction at the same condition. What’s more, as the micro-heterogeneity of the minerals causes the reaction interface to be complex, interactive and irregular, it is guessed that the interlaced and jagged reaction interface can be amended by adopting “Probability Interface Model” through experimental methods, thus the closer factual reduction process can be further actually expressed. Consequently, taking Liaoxi high-vanadium-titanium low-grade magnetite as the object, this project focuses on the physical and chemistry problems of the mineral phases, factual reaction interface and apparent reduction kinetics including the establishment of reduction equation and mineral phases of the single oxide, the establishment of reduction equation and mineral phases of complex oxides, the interactive influence and coupled reaction regular pattern in the reduction process of different oxides, the reduction product layer mass transfer and interface diffusion regular pattern, the modelling of “Probability Interface Model” and amending for the factual reaction interface. This project will help to make clear the relation between the apparent reduction kinetics and complex reaction interface for Liaoxi high-vanadium-titanium low-grade magnetite and enrich and perfect the reduction theory of vanadium-titanium magnetite.

实验室初步研究结果表明辽西高钒钛低品位磁铁矿的还原规律和普通钒钛磁铁矿差别较大，故猜想在同样的还原条件下，有多种参与还原的氧化物的反应界面协同控制着该矿总的反应速度及反应界面（“反应带”）。又由于矿物微观不均匀性，导致反应界面的复杂性、交互性、不规则性，故猜想通过实验的方法，采用“概率界面模型”对交错的、参差不齐的反应界面进行修正，更净真的表达接近实际还原的过程。因此，本项目以辽西高钒钛低铁型磁铁矿为研究对象，研究该矿还原过程的矿相、实际反应界面及表观动力学等物理化学问题，包括：简单氧化物还原反应方程的建立与矿相研究，复合氧化物还原反应方程的建立与矿相研究，不同氧化物还原过程的交互影响及耦合反应规律研究，还原产物层传质及界面扩散规律研究，“概率界面模型”的构建及对实际反应界面的修正研究。本项目将明晰辽西高钒钛低品位磁铁矿表观还原动力学与复杂反应界面的关系，将丰富完善钒钛磁铁矿的还原理论。

2008年新近发现的200亿吨高钒钛低品位磁铁矿相较攀枝花、承德等地钒钛磁铁矿，资源特殊，还原规律等存在较大差别，而针对该类钒钛磁铁矿在相关方面的系统研究处于空白。在同样的还原条件下，有多种参与还原的氧化物的反应界面协同控制着该矿总的反应速度及反应界面。项目以该矿为研究对象，在研究工艺矿物学的基础上，获得了高钒钛低品位磁铁矿氧化球团的制备过程参数，开展了高钒钛低品位磁铁矿氧化球团的还原行为、表观动力学及过程矿相等研究，为将来可能的实际生产应用提供理论支撑和技术参考。明晰了有价组元TiO2、Cr2O3等对铁氧化物还原的具体影响及不同组元影响下还原过程的矿相变化，建立了相关的表观动力学方程，研究了还原过程的界面变化。研究了有价组元对铁氧化物还原的影响叠加，实现了与高钒钛低品位磁铁矿还原的比对，并构建了相关的还原动力学模型，开展了表观还原动力学与复杂反应界面关系的相关验证，为高钒钛低品位磁铁矿的高效还原、综合利用提供了理论支撑和技术依据。项目完成期间，发表相关学术论文7篇，获授权发明专利5项，培养研究生2名、本科生1名，参加国内学术会议7次、作学术报告6次。