Magnetic and flotation studies of banded hematite quartzite (BHQ) ore for the production of pellet grade concentrate

To identify and establish beneficiation techniques for banded hematite quartzite （BHQ） iron ore, a comprehensive research on BHQ ore treatment was carried out. The BHQ ore was assayed as 38.9wt% Fe, 42.5wt% SiO2, and 1.0wt% Al2O3. In this ore, hematite and quartz are present as the major mineral phases where goethite, martite, and magnetite are present in small amounts. The liberation of hematite particles can be enhanced to about 82% by reducing the particle size to below 63 μm. The rejection of silica particles can be obtained by magnetic and flotation separation techniques. Overall, the BHQ ore can be enriched to 65.3wt% Fe at 61.9% iron recovery. A flowsheet has been suggested for the commercial exploitation of the BHQ ore.

Effect of reverse flotation on magnetic separation concentrates

Reverse flotation studies on magnetite samples have revealed that the use of starch as a depressant of Fe-oxides has a hydrophilic effect on the surface of Fe-bearing silicates and significantly decreases Fe in the silica-rich stream when used in combination with an amine （Lilaflot D817M）. In this study, the effect of reverse flotation on the optimization of products obtained fi＇om magnetic separation was inves- tigated. Two different magnetic samples, zones 1 and 2, were milled to 〈75 btm and then subjected to low intensity magnetic separation （LIMS）. The LIMS test conducted on the 〈75 ~m shown an upgrade of 46.40wt% Fe, 28.40wt% SiO2 and 2.61wt% MnO for zone 1 and 47.60wt% Fe, 29.17wt% SiO2 and 0.50wt% MnO for zone 2. Further milling of the ore to 〈25 ~tm resulted in a higher magnetic-rich product after magnetic separation. Reverse flotation tests were conducted on the agitated magnetic concentrate feed, and the result shows a significant upgrade of Fe compared to that obtained from the non-agitated feed. Iron concentrations greater than 69%, and SiO2 concentrations less than 2% with overall magnetite recoveries greater than 67% and 71% were obtained for zones 1 and 2, respectively.

Effect of magnetic seeding agglomeration on flotation of fine minerals

Magnetic seeding agglomeration(MSA),i.e.,adding magnetic seeds and a low intensity pre-magnetization for fine agglomeration,was applied to the flotation of coal,pyrite and hematite ore slimes.Size analysis and flotation tests highlight that the MSA improved flotation recovery and kinetics of pyrite ore while causing some loss in selectivity,and in the presences of the polyacrylamide for coal and starch for hematite the agglomeration flotation was further strengthened due to the synergetic effect between the flocculants and magnetic seeds.Magnetism analyses and calculation confirmed the adsorption of magnetic seeds onto minerals,resulting in a decreased threshold magnetic field intensity for the MSA to happen.Then atomic force microscope(AFM)study found that there exists a long range force between magnetic seeds and minerals,which facilitates the adsorption of magnetic seeds on minerals.FTIR shows both the polyacrylamide and starch adsorbed onto minerals and magnetic seeds,thus acting as the bridging media between minerals and magnetic seeds,intensifying the agglomeration in flotation.Surface characterization of the MSA was understood by SEM imaging,and models of the MSA were proposed.

Flotation-Calcination-Magnetic Separation Hybrid Process for Concentration of Rare Earth Minerals Contained in a Carbonatite Ore

A hybrid process consisting of flotation and magnetic separation has been developed to concentrate multi-phase rare earth minerals associated with a carbonatite ore that contains a significant amount of niobium. The deposit is known to contain at least 15 different rare earth minerals identified as silicocarbonatite, magnesiocarbonatite, ferrocarbonatites, calciocarbonatite, REE/Nb ferrocarbonatite, phosphates and niobates. Although no collector exists to float all the different rare earth minerals, the hydroxamic acid-based collectors have shown adequate efficiency in floating most of these minerals. 92% recovery of total rare earth oxide (TREO) and niobium in 45% mass was possible at d80 of <65 microns grind size. It was also possible to reduce the mass pull to 28%, but TREO and Nb’s recovery dropped to 85%. Calcination of the concentrate followed by quenching and fine grinding to <25 μm allowed upgrading the flotation concentrate by magnetic separation. It was demonstrated that at least 87% TREO and 85% Nb could be recovered in 16% of the feed mass. The paper discusses the overall concept of the flowsheet and the experimental strategies that led to this process.

New Technology “Flotation to Form Agglomerates and Magnetic Separation” Allows Great Breakthrough for World Low-Grade Light Rare Earth Ores

Rare earth resources are relatively scarce worldwide, but their global consumption is increasing year-by-year. At present, China has about 36% of the global rare earth reserves, but provides 90% of the world＇s supply, which has generally met world demand and promoted the development of the world economy. In order to continuously and stably supply rare earths to international markets, the Chinese Government has financially supported the Institute of Multipurpose Utilization of Mineral Resources within the China Geological Survey to study the utilization of low-grade rare earth ores. Following many years of experimental research, the project has developed a new technology entitled ＂Flotation to Form Agglomerates and then Magnetic Separation＂, which will bring a technological revolution to the world＇s light rare earth ore dressing.

Self-magnetization of pyrite and its application in flotation

Pyrite is a special weakly magnetic mineral containing Fe(II). Its self-magnetization only by adjusting slurry temperatureand pH value was able to enhance its magnetism, producing the so-called the magnetized pyrite, which was further used as magneticseeds in the flotation of pyrite ore to promote flotation recovery. Tests, such as self-magnetization, vibrating sample magnetometer(VSM), XPS, size analysis and flotation were carried out. The optimal conditions of the pyrite self-magnetization were pulp pH of11.81 and temperature of 65 °C. The magnetized pyrite was characteristic of the valence change of elemental iron, resulting instronger magnetism of the magnetized pyrite than that of the original pyrite. Then, this magnetized pyrite was applied to the magneticseeding flotation (MSF) of pyrite ore. It was found that the recovery of pyrite flotation grew with the increase of magneticsusceptibility of the magnetic seeds?the magnetized pyrite; and the proper dosage of the magnetized pyrite was 100 g/t. The reasonbehind the increased recovery lies in that the magnetized pyrite promoted the magnetic agglomeration between fine pyrite particles;and the fact that the stronger the magnetism of the magnetized pyrite, the larger the aggregate size, indicates that the agglomeration issomewhat in line with the flotation, also confirming that the MSF is more suitable for fine particles than traditional flotation.

Research on Effect of Magnetized Pulp on Coal Slime Flotation

Effect of magnetization on oxygen concentration, pH, surface zeta potential, and wet heat of flotation pulp were researched. The result shows that magnetization treatment can improve the floatablility of coal and increase the difference in wet heat among coal, refuse, and pyrite, which is favorable for slime flotation and for removing sulfur and ash from coal.

Study on the pre-treatment of oxidized zinc ore prior to flotation

The pre-treatment of zinc oxide bearing ores with high slime content is important to ensure that resources are utilized optimally. This paper reports an improved process using hydrocyclone de-sliming, dispersion reagents, and magnetic removal of iron minerals for the pre-treatment of zinc oxide ore with a high slime and iron content, and the benefits compared to traditional technologies are shown. In addition, this paper investigates the damage related to fine slime and iron during zinc oxide flotation, the necessity of using hydrocyclone de-sliming together with dispersion reagents to alleviate the influence of slime, and interactions among hydrocyclone de-sliming, reagent dispersion, and magnetic iron removal. Results show that under optimized operating conditions the entire beneficiation technology results in a flotation concentrate with a Zn grade of 34.66% and a recovery of 73.41%.

基于浮选法和磁选法的高炉喷吹煤粉利用率分析

高炉喷吹煤粉技术可降低炼铁工序的燃料成本,通过降低焦炭消耗来减少炼焦工序产生的环境污染。高炉喷吹煤粉利用率是评价煤粉对焦炭置换作用的重要指标。文章以某钢铁企业3座高炉产生的除尘灰为实验样品,利用化学纯Fe_(3)O_(4)配制不同密度的悬浊液,依次经过浮选、磁选、灼烧手段确定未燃煤粉和焦炭粉末的质量,进而计算出高炉喷吹煤粉的利用率。与现行岩相分析确定的高炉喷吹煤粉利用率进行对比,浮选法和磁选法计算出的煤粉利用率为具体数值,更加精确,可为高炉炼铁调整燃料结构和优化操作工艺提供科学依据。

微细粒矿物疏水团聚浮选新技术研究进展

微细粒矿物由于粒径小、质量轻,在浮选过程中难以与气泡充分矿化,导致回收率显著降低,限制了矿物资源的高效利用。为解决这一问题,研究者提出通过增大颗粒表观直径以提高颗粒与气泡碰撞概率,从而增强矿化效率的策略,这一策略已在一定程度上通过载体浮选、油团聚浮选和絮凝浮选等传统技术得以实现。然而,传统技术在实际应用中面临工艺复杂、成本高、操作稳定性差等挑战,限制了其在大规模工业化生产中的应用。近年来,微纳米气泡及外场(如超声驻波场和磁场)强化实现的疏水团聚技术引起了广泛关注。这些新技术通过创新矿化机制,显著提高了微细粒矿物与气泡的结合效率。微纳米气泡通过其高比表面积和独特的物理化学特性,增强了微细粒矿物颗粒的聚团效应和与浮选气泡的结合效率,从而显著提高浮选回收率。超声驻波场技术通过声辐射力驱动颗粒聚集,增加颗粒表观直径,进一步优化了矿化效果。磁场技术则通过加入磁性颗粒,使微细粒矿物在外加磁场的作用下形成较大聚集体,从而增加颗粒与气泡的碰撞概率,显著提升浮选效率。这些新兴技术不仅提高了浮选回收率,还在操作稳定性和经济效益方面展现出明显的优势。

安徽某磁铁矿选矿试验

安徽某铁矿TFe品位39.23%,有用矿物主要为磁铁矿,分布率为82.63%,主要有害杂质SiO_(2)含量17.56%。为了回收利用该磁铁矿,利用磁选—阶段磨矿—磁选工艺系统地研究了磨矿细度和磁选磁场强度对分选指标的影响。试验结果表明:在一段磨矿细度为-0.076mm50%,一段磁选磁场强度为159.15 kA/m,二段磨矿细度为-0.076 mm95%,二段磁选粗选及精选磁场强度分别为143.24,111.41 kA/m的条件下,获得了铁品位63.50%、铁回收率82.92%的铁精矿;采用细筛工艺,可获得产率50.55%、铁品位63.82%、铁回收率82.70%的铁精矿;对磁选尾矿进行浮选回收硫矿物探索试验结果表明,浮选回收硫的效果较差,难以获得高品位的硫精矿,尾矿硫矿物回收利用价值较小。

酒钢悬浮焙烧磁铁矿选矿工艺优化研究

对酒钢悬浮焙烧磁铁矿进行了磨矿-选矿工艺优化研究。采用110 mT低场强磁选机预提精、中矿再磨后采用磁选富集抛尾、富集精矿经阳离子反浮选,最终获得TFe品位60.06%、SiO_(2)含量5.17%、金属回收率84.27%的综合精矿;与原工艺指标相比,精矿TFe品位提高了1.96个百分点,金属回收率提高了1.38个百分点,SiO_(2)含量降低了1.06个百分点。

乌干达某铁铌多金属矿石中铌与重晶石的回收试验

乌干达某铌多金属矿原矿风化严重,矿石性质复杂,属极难选多金属矿,矿石TFe品位为39.78%,REO品位为1.79%,Nb_(2)O_(5)品位为0.62%,BaO品位为7.68%;主要脉石矿物为石英、长石和高岭石等。为了高效回收利用该矿石资源中伴生的铌和重晶石,以现场磁选铁尾矿为对象,采用重磁联合预富集、反浮选分离铌与重晶石的工艺流程进行了选矿试验。试验结果表明:现场磁选铁尾矿采用1次摇床重选、1次弱磁选、1粗4精1精扫2扫闭路浮选流程处理,最终可获得Nb_(2)O_(5)品位7.33%、回收率41.94%的铌精矿,BaSO_(4)品位94.23%、回收率50.98%的重晶石精矿。研究结果可作为现场开展伴生铌和重晶石回收工艺改造的依据。

某铁尾矿回收钛选矿工艺研究

某选厂选铁尾矿中TiO_(2)的含量为8.96%。为综合回收该选铁尾矿中的TiO_(2),通过矿石性质研究,查明了TiO_(2)的存在形式和主要产出形式,在此基础上,开展了系统的选矿工艺研究,开发了“强磁选预富集—强磁精矿浮选再富集”选矿工艺技术,可以获得TiO_(2)品位45.26%、回收率76.42%的钛精矿产品。研究成果为该选厂综合回收选铁尾矿中的钛资源提供了技术支持。

新型捕收剂DPY-4反浮选酒泉铁矿焙烧后的磁选精矿

酒钢选矿厂铁矿石矿物组成复杂、矿石品位低、共伴生成分较多,其磁选精矿铁品位低、石英等脉石矿物含量高,属于难选铁矿石,酒钢选矿厂采用反浮选流程处理焙烧磁选精矿。新型常温反浮选捕收剂DPY-4可提高铁矿石的品位及回收率,为难选铁矿石的高效反浮选药剂。为研究该捕收剂对该矿石分选的有效性,进行了系统的选矿试验和机理分析。对石英和磁铁矿进行纯矿物浮选条件试验,在DPY-4浮选体系下,当pH=5、温度25℃、DPY-4用量为20 mg/L、抑制剂玉米淀粉用量40 mg/L时,石英和磁铁矿的回收率分别为92.51%和4.46%。针对酒钢选矿厂悬浮磁化焙烧后的三段磁选精矿进行反浮选试验,在矿浆温度25℃、DPY-4用量300 g/t、玉米淀粉用量600 g/t、pH=9.5时,获得的开路浮选精矿铁品位60.48%、铁回收率69.24%,闭路浮选精矿铁品位58.35%、铁回收率94.05%、SiO_(2)含量为4.62%。DPY-4不仅捕收能力强,而且选择性优异,这主要是因为DPY-4在石英表面能发生强烈的吸附作用,包括物理吸附和氢键吸附,玉米淀粉在石英表面吸附较弱,而对磁铁矿的作用相反。

安徽某高砷含金硫精矿硫砷分离试验研究

针对安徽某含金硫精矿砷含量较高(达5.05%),无法销售的问题,进行了砷硫分离试验。结果表明,以活性炭为脱药剂,石灰为pH值调整剂,ZJY-7为抑制剂,丁基黄药为捕收剂,2^(#)油为起泡剂,优先浮选黄铁矿,浮选尾矿磨细至-0.074 mm占82.37%,经过1粗1扫磁选分离毒砂和磁黄铁矿,获得了可销售的含硫52.16%,含砷0.48%,含金1.86 g/t,硫回收率14.32%的硫精矿1,含硫35.81%,含砷0.63%,含金0.61g/t,硫回收率64.08%的硫铁精矿2和含砷16.46%,含金8.14 g/t,砷回收率91.25%,金回收率80.22%的含金砷精矿,合计硫回收率78.40%。试验结果可为同类矿山处理高砷含金硫精矿提供参考与借鉴。

酒钢肃南宏兴矿业铜尾矿中有价元素回收试验研究

酒钢肃南宏兴矿业铜矿石中伴生有价元素Fe、Ba,Fe主要以菱铁矿的形式赋存、Ba以重晶石的形式赋存,浮选选铜后有价元素Fe、Ba富集于尾矿中。试验确定铜尾矿有价元素回收工艺为强磁选-悬浮焙烧-磨矿-弱磁选回收铁精矿,强磁选尾矿浮选回收重晶石。采用此工艺,在铜浮选尾矿含Fe 10.8%、BaO 4.7%的情况下,试验回收铁精矿含Fe 56.4%,回收重晶石含BaSO 488.79%。由于Fe回收只需新建强磁选和脱水工序,强磁选回收铁矿粉进酒钢选矿厂现有悬浮磁化焙烧选别系统即可,投资小、易实施。

江西某脉石英制备4N5级高纯石英砂试验研究

利用江西某脉石英岩心矿石制备高纯石英砂,探究了磨矿时间、磁选、擦洗、矿浆pH值对高纯石英砂纯度的影响,确定最佳试验条件,采用4段磁选-2段擦洗-2段水洗-2段浮选-2段脱药-焙烧-水淬-酸浸工艺,得到的最终产品石英砂SiO_(2)含量(质量分数,下同)达到4N5级,总杂质含量为54.84μg/g,其中Al元素含量为16.76μg/g,Na元素含量为5.83μg/g,K元素含量为6.46μg/g,Fe元素含量为17.50μg/g。该工艺对对脉石英矿物制备高纯石英砂具有一定指导意义。

酒钢悬浮磁化焙烧技术配套工艺及设施浅析

悬浮磁化焙烧-弱磁选是酒钢集团选矿厂处理镜铁山式难选铁矿石的新工艺,该工艺于2018年应用于选矿厂,取得铁精矿品位55%,回收率86%的良好指标。但由于悬浮炉配套系统的不稳定,如磨矿粒度、压滤后精矿水分、泵及管道运输易堵塞等,影响悬浮炉的正常生产。主要探讨了悬浮炉配套工艺预先筛分、磨矿分级、磁选、浮选、过滤系统的设备对悬浮炉的影响。