低品位钒钛磁铁精矿直接还原—磨选工艺研究

发布时间：2018-03-02 10:24

本文关键词： 低品位钒钛磁铁精矿铁颗粒长大强化还原磁选分离　出处：《昆明理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：钒钛磁铁矿是我国的重大特色战略资源,远景储量可达400亿吨,是一种以铁、钒、钛等多种金属共伴生的矿产资源,具有很高的综合利用价值。随着我国优质钒钛资源的逐年减少,对外依存度逐年增大,加强超贫钒钛磁铁矿资源高效、清洁、综合开发利用,对提高我国资源保障量、促进钒钛产业可持续发展具有重大意义。目前我国对钒钛磁铁矿的研究工作大多偏重于高品位钒钛磁铁矿或者高铬型钒钛磁铁矿,有关超贫钒钛磁铁矿综合开发和利用的研究报道较少,辽西地区的钒钛磁铁矿由于铁含量低而钒钛含量高,具有非常高的综合利用价值,本文以辽西地区超贫钒钛磁铁矿选矿后得到的低品位钒钛磁铁精矿为原料,系统开展了低品位钒钛磁铁精矿直接还原、强化还原、过程强化、磨选分离的研究,实现了低品位钒钛磁铁精矿中铁与钒/钛的高效分离,取得了以下创新性成果:(1)系统研究了低品位钒钛磁铁精矿直接还原过程中铁、钒、钛的还原行为,获得了铁、钒、钛的迁移规律。结果表明:通过控制C/Fe摩尔比和还原温度,可使低品位钒钛磁铁精矿中的钒不被还原而随钛进入钒钛渣。获得优化的还原条件:C/Fe摩尔比为1.2,还原温度1200℃,还原时间120 min。添加复合添加剂可使低品位钒钛磁铁精矿的金属化率达91.3%,铁、钒、钛的回收率分别达到96.2%、85.4%、88.6%,使用水淬冷却强化可脱去还原产物中39.5%的硫。(2)直接还原过程中金属铁颗粒长大的研究表明:提高还原温度可以促进直接还原过程中金属铁颗粒的长大,但是过高的温度不利于铁钒磁选分离,因此比较适宜的还原温度为1200℃。添加钠盐可以破坏铁橄榄石和铁尖晶石的矿相结构,生成低熔点的物质,改善了金属铁相的扩散条件,从而可以得到粒径较粗的铁颗粒。复合添加剂的不同的阴离子的共同作用,相比单一的钠盐添加剂,促进铁颗粒长大的效果更加明显。(3)深入探究了磨矿细度和磁场强度对铁钒钛的回收率的影响,发现随着磨矿时间的增加,粒度越来越细,回收率不会随着粒度的变小而提升,获得最适宜的磨矿时间为30 min,粒度为14 μm,磁场强度为100 mT,铁的回收率为94.67%,品位为97.31%。
[Abstract]:The major characteristics of vanadium titanium magnetite is our strategic resources, prospective reserves of up to 400 tons, is a kind of iron, vanadium, titanium and other metals were associated with the comprehensive utilization of mineral resources, has a very high value. With the development of high quality vanadium resources in China decreased year by year, the foreign dependency increases each year, to strengthen the ultra poor vanadium titanium magnetite resources efficient, clean, comprehensive development and utilization of resources, improve our security, is of great significance to promote the sustainable development of vanadium and titanium industry. At present our country of vanadium titanium magnetite mostly focuses on the research work of high grade titanomagnetite or high chromium vanadium titanium magnetite, and the related reports by ultra poor vanadium titanium magnetite comprehensive development is less. In the western area due to low levels of iron and vanadium titanium magnetite vanadium content is high, has the very high value of comprehensive utilization, in order to get western Liaoning ultra poor vanadium titanium magnetite ore. Low grade vanadium titanium magnetite concentrate as raw material, system to carry out a low grade titanomagnetite direct reduction, strengthening reduction, process intensification, grinding of separation, to achieve an efficient separation of low grade titanomagnetite in iron and vanadium / titanium, has obtained the following innovative achievements: (1) the system of low grade vanadium titanium magnetite the direct reduction process of iron ore, vanadium, titanium reduction behavior, the iron, vanadium, titanium migration. The results showed that by controlling the molar ratio of C/Fe and reduction temperature, the low grade titanomagnetite in vanadium and titanium with can't be reduced into vanadium titanium slag. Reducing conditions optimization: C/Fe molar ratio 1.2, reduction temperature of 1200 DEG C, the reduction time of 120 min. composite additive can make metal of low grade titanomagnetite rate reached 91.3%, iron, vanadium, titanium recovery rate reached 96.2%, respectively, 85.4%, 88.6%, the use of water quenching can be enhanced Remove the reduction product of 39.5% s. (2) research on direct reduction of iron in the process of growing up shows that the increase of the reduction temperature can promote the direct reduction of iron in the process of growing up, but the high temperature is not conducive to the separation of Fe-V, so it is suitable the temperature of 1200 DEG. Adding sodium salt can destroy the structure fayalite and hercynite mineral phase, producing low melting point metal material, improve the iron phase diffusion conditions, so as to obtain the coarse grain size of the iron particles. The interaction of compound additives of different anions, compared to single sodium additives, promote the grain growth effect is more obvious. (3) the in-depth study of the effect of recovery of grinding fineness and the strength of the magnetic field of Fe-V titanium ratio, with the increase of grinding time, more and more finer, the recovery rate will not improve as the size of the smaller, get the most The suitable grinding time is 30 min, the grain size is 14 mu m, the magnetic field strength is 100 mT, the iron recovery rate is 94.67%, the grade is 97.31%.

【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD95

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