复杂难选铁矿石悬浮磁化焙烧-高效分选技术

针对传统铁矿石磁化焙烧技术与装备存在焙烧产品质量差、产能低、能耗高和环境污染严重等问题,创造性提出了一种"预热-蓄热还原-再氧化"悬浮磁化焙烧新工艺。该工艺具有原料适应性广、焙烧产品质量均匀、回收率高、生产能耗低、无污染等特点,适合处理赤铁矿、褐铁矿、菱铁矿及其混合型难选铁矿石。通过多年的潜心基础研究与技术攻关,形成了非均质矿石颗粒悬浮态流动控制、蓄热式高效低温还原、铁物相精准调控与余热同步回收等一系列关键技术,建成了500 kg/h复杂难选铁矿石悬浮磁化焙烧-高效分选半工业试验平台。酒泉钢铁(集团)有限责任公司建成了165万t/a的粉矿悬浮磁化焙烧工业化生产线,为难选铁矿资源的高效利用开辟了新途径。     

铁矿石焙烧-磁选探索性试验研究

通过对新疆地区某难选铁矿石的还原焙烧选矿试验进行研究,论述了还原焙烧-磁选选矿技术的可行性。同时,针对目前疆内的资源情况,提出难选贫矿的磁化焙烧技术的发展方向。     

贫杂难选铁矿高效生态化利用的现状与前景

分析了我国贫杂铁矿石以及超贫表外矿等资源的特点,综述了高效选矿-深度还原一体化技术、流态化磁化焙烧、低品质难选矿转底炉制粒铁等贫杂难选铁矿资源高效利用方法的发展现状,同时分析了各种贫杂铁矿利用技术的优缺点,提出贫杂难选铁矿资源高效生态化利用的可行途径为深度还原同时生产胶凝材料     

块状铁矿石竖炉磁化焙烧的工艺优化

竖炉磁化焙烧是处理难选红铁矿较有效的方法。通过对弱磁块矿竖炉磁化焙烧的试验研究,提出了更加科学、高效的竖炉磁化焙烧理论,在现有鞍山式竖炉的基础上,通过高效控制铁矿石竖炉磁化焙烧还原气氛,对竖炉磁化焙烧工艺进行了优化。结果表明：还原气体H2体积分数提高到12%±1%,同时降低CO体积分数,提高块矿焙烧还原温度,可获得最佳的磁化焙烧效果;通过独立设置铁矿石磁化焙烧还原煤气系统与加热煤气系统,可实现还原煤气的成分、流量、压力灵活调节;通过减少还原煤气总量,将矿石还原煤气量降低至1400～1600m3/h,降低竖炉的生产成本;通过独立的还原煤气系统,提高还原煤气中焦炉煤气比例,将H2体积分数控制在12%±1%,矿石磁化率控制在2.33左右,降低了竖炉磁化焙烧煤气消耗,提高矿石磁化焙烧质量;为保证还原煤气降低用量后的压力和喷出的均匀性,将还原煤气喷出塔的出口面积缩小50%,使矿石能够充分、均匀地完成还原。     

安徽褐铁矿的磁化焙烧-磁选工艺

针对安徽某低品位褐铁矿石,采用磁化焙烧-磁选工艺进行了实验研究,对该矿的原矿进行了岩相分析,并对磁化焙烧-磁选工艺参数进行了优化.结果表明,该矿属低磷硫的低品位褐铁矿,褐铁矿与脉石矿物的镶嵌关系较为复杂,结晶水含量高,属难选矿石.对铁品位48.01%的原矿,在850℃、内配煤5%(质量分数)的条件下,磁化焙烧15min,焙烧矿磁化率达到最佳值,褐铁矿几乎全部转化为磁铁矿,这由X射线衍射结果证实.该褐铁矿通过磁化焙烧-磁选工艺可获得品位62.94%、回收率87.99%的铁精矿.     

低品位褐铁矿的磁化焙烧

针对河北宣化某难选褐铁矿石,采用SEM和XRD对原矿物性结构及成分进行了分析,并运用磁化焙烧-磁选工艺进行了实验研究并对磁化焙烧-磁选工艺参数进行了优化。物相分析结果表明,该褐铁矿与脉石矿物的镶嵌关系较为复杂,SiO2含量高,运用常规的选矿方法难以分选提纯。实验结果表明,磁化焙烧-磁选工艺可以较好地完成该铁矿石的提纯。对该褐铁矿原矿在焙烧温度为950℃,焙烧时间为15min,配煤量为5%,焙烧矿粒度为150μm和磁场强度为60mT的条件下,可以得到精矿产率为43.68%,铁精矿品位为53.98%,铁回收率83.91%,wSiO2为13.9%的良好指标。     

大冶铁矿强磁选精矿磁化焙烧热力学研究

磁化焙烧-磁选分离的技术路线,是解决菱铁矿含量较高的大冶铁矿尾矿中低品位难选红铁矿(w(TFe)=34%左右)的有效工艺.其焙烧工艺参数对工艺效率影响较大.对其热力学反应条件进行了分析,依靠碳酸铁的自身分解产物CO和还原气氛,大冶低品位含菱铁矿弱磁性铁矿能在弱还原气氛条件下,在10～0 s内完成整个磁化焙烧过程.磁化焙烧后,弱磁选精矿铁品位大大提高(w(TFe)》60%).     

贫赤铁-黄金尾渣悬浮态磁化焙烧选矿试验

针对河南黄金尾渣中低品位、难选的赤铁矿,采用悬浮态磁化焙烧-磁选工艺和阶段粉磨-磁选工艺流程对该黄金尾渣进行选矿试验,并取得了良好的效果:原矿铁品位只有27.30％,在焙烧温度750～850℃、焙烧时间2～3 s的煤基直接还原和一定的粉磨-磁选条件下,获得铁品位56.05％、回收率77.51％的铁精矿.分析了影响焙烧磁选的主要因素.     

块状铁矿石竖炉磁化焙烧工艺参数优化试验研究

本文针对镜铁矿矿物组成复杂及晶粒度较细特点,为提高铁矿石竖炉磁化焙烧的质量,从焙烧温度、焙烧粒度、还原气、焙烧时间等方面进行了气试验研究,得出了合理的铁矿石竖炉磁化焙烧工艺控制参数。     

高磷鲕状赤铁矿焙烧-磁选-反浮选试验研究

鄂西高磷鲡状赤铁矿复杂、难选。研究表明,采用还原磁化焙烧-弱磁选-阴离子反浮选流程是最现实的选别方案,可得产率56．20％、品位TFe61．88％、回收率79．95％的铁精矿,为开发同类或类似复杂难选铁矿提供参考、借鉴作用。     

黄梅褐铁矿悬浮闪速磁化焙烧试验研究

以湖北黄梅褐铁矿为主要原料,研究焙烧气氛、温度和固气比等操作条件对褐铁矿焙烧指标的影响。研究结果表明:在一氧化碳含量(体积分数)3.50%左右,反应炉温度800～950℃,固气比0.5～0.8kg/m3条件下,通过闪速磁化焙烧得到的焙烧矿,品位在33%左右,可选性良好,采用简单的选矿流程,可得到较好的选矿指标,铁精矿品位达到60.67%,回收率达到94.49%.可见新研制的闪速磁化焙烧装置对褐铁矿的焙烧效果是很显著的。     

Characterisation-Assisted Reduction Roasting of BHJ,West Singhbhum,Jharkhand, India

During the mining of high-grade iron ore, considerable amount of waste is generated. This poses a serious challenge to the environment as well as humans. But, with the depletion of high-grade ores, the Banded Haematite Jasper (BHJ) ore generated as a waste has attracted attention as an alternative source of iron. The purpose for this study is to develop the energy efficient process route for harnessing the Banded Hematite Jasper. Utilisation of the ore as a source of iron will also serve the additional purpose of getting rid of a major burden on the environment. Reduction roasting is a promising route for the beneficiation of the ore for the recovery of iron values profitably. However, no studies have been reported correlating the influence of the properties of the ore on the roasting process. This is crucial for developing a viable process route for reduction roasting. Preliminary characterization study of the sample indicated the presence of prismatic and specularity hematite grains embedded in fine grained siliceous matrix and vice versa. The ore contained 43.06% Fe, 36.54% SiO₂ and 0.21% Al₂O₃. Davies Tube magnetic separator of the ore indicated the absence of highly magnetic materials in the ore. Magnetic separation of the roasted ore resulted in significant enrichment of the ore with respect to iron. The optimized parameters for reduction roasting were 13 mm particle size, 60 min roasting time and 600 °C temperature.     

原矿焙烧-焙砂氰化工艺处理鹿峰金矿矿石研究与实践

采用原矿焙烧-焙砂氰化浸出工艺处理鹿峰金矿难选冶金矿石，金的回收率达80％，选矿吨矿综合成本为70无左右，技术指标较好，经济效益显。     

某褐铁矿磁化焙烧-磁选工艺的探讨

通过对某复杂褐铁矿进行磁化焙烧-磁选工艺条件的研究,在最佳焙烧温度750℃,焙烧时间50min,还原剂用量7％的磁化焙烧条件下,采用探索实验流程获得了铁精矿品位56．59％,铁回收率为74．60％的良好指标,对开发同类型矿石具有借鉴意义。     

Magnetic properties of low-grade hematite ore after magnetizing reduction and reoxidation using a fluidized bed

Magnetizing roasting via a fluidized bed,which was recognized as an efficient method for beneficiation of low-grade iron ores,has attracted much attention in China recently due to the fluctuation of the international iron ore market.In order to examine the effects of magnetic properties on the separability and to optimize the operating parameters,magnetic susceptibility and coercivity of a low-grade hematite after magnetizing reduction and reoxidation under different conditions were investigated.It was found that the magnetic susceptibility of roasted ore increased with reduction degree and particle diameter to different degrees.The magnetite was re-oxidized to maghemite when the temperature was below 400℃,and the magnetic susceptibility decreased slightly.The recovery efficiency decreased notably with the particle size for very fine grains although no significant change was found in magnetic susceptibility.The coercivity and remanence of roasted ores decreased with increasing roasting temperature.The scanning electron microscope(SEM) study showed that more cracks were produced by the reoxidation of reduced ores,which could possibly favor the intergranular fracturing and the liberation for further treatment.     

红土镍矿选择性还原焙烧过程中的相变转化

针对传统选矿方法难以回收低品位红七镍矿中有价金属镍的问题,采用选择性还原焙烧法研究了不同焙烧温度以及不同焙烧时间条件下红土镍矿(Ni品化为1.49%)中发生的微观结构变化以及相变转化.通过X射线衍射、扫描电镜及X射线能谱分析等测试手段分析表明,在不同焙烧温度及不同时间条件下经选择性还原后的红土镍矿中,镍氧化物逐渐被还原成镍铁合金相,铁氧化物主要转变成浮氏体相,硅酸盐主要以橄榄石形式存在.最后通过还原焙烧磁选试验证实,还原剂为烟煤,添加剂为NCS,两者用量分别为原矿质量的2%和7%,在1200℃条件下焙烧50min,磁选分离得到镍铁产品中镍品位为9.78%,镍的回收率为92.06%,镍铁回收率差为62.51%,实现了红土镍矿中镍铁的选择性还原.      

Metallization of siderite ore in reducing roasting

The behavior of the initial ore and the concentrate of magnetoroasting beneficiation during metallization under the conditions that are close to those for reducing roasting of iron ores in a rotary furnace is studied in terms of works on extending the field of application of Bakal siderites. A difference in the mechanisms of the metallization of crude ore and the roasted concentrate is observed. The metallization of roasted concentrate lumps is more efficient than that of crude siderite ore. In this case, the process ends earlier and can be carried out at higher temperatures (1250–1300°C) without danger of skull formation.     

Tin and zinc separation from tin,zinc bearing complex iron ores by selective reduction process

Abstract

Tin, zinc bearing complex iron ores are typically intractable and have not been efficiently utilised in China. In this investigation, the process mineralogy of the tin, zinc bearing iron ores and reduction behaviours of iron, tin and zinc oxides by CO were investigated. A selective reduction roasting process was initially developed to separate tin and zinc from the complex iron ores. Under optimum conditions, most of the tin and zinc were effectively removed from the iron ore pellets, and the roasted pellets could be used as high quality ironmaking burdens for large scale blast furnaces.     

铷的应用及提取工艺研究进展

近年来，由于铷优良的物理化学性能，铷不仅在电子器件、特种玻璃、医药等传统领域有着重要用途，而且在磁流体发电、离子推进发动机等新型能源科技领域也显现出无限的活力。铷主要存在于矿石和盐湖卤水资源中，从含铷矿石中提铷比较成熟的工艺主要有硫酸分解法和焙烧分解法，传统的矿石提铷工艺存在流程复杂、污染大、能耗高等问题，对实现“双碳”目标构成严峻考验。分析表明，溶剂萃取法和离子交换法在解决盐湖卤水等液态资源提铷方面更具有发展前景。盐湖卤水提铷工艺简单，能耗低，无矿石分解过程，避免了大量固体废渣的产生，环境友好。文中在分析各类含铷矿石以及盐湖卤水资源特点的基础上，简述了铷资源在各领域的用途，综合介绍了硫酸分解法、碳酸盐焙烧法、氯化焙烧法、溶剂萃取法以及离子交换法等关键提铷技术的工艺研究现状及优缺点，展望了清洁环保、高效提铷的发展方向。