高磷鲕状赤铁矿添加脱磷剂还原焙烧脱磷机理(英文)

高磷鲕状赤铁矿是一种典型的难处理铁矿石,采用常规的选矿方法难以得到较好的提铁降磷指标。采用添加脱磷剂还原焙烧,然后对焙烧产物进行两段磨矿磁选来处理此类矿石,获得了较好的选别指标。实验结果表明,铁的品位从43.65%(原矿)提高到90.23%(磁选精矿),磷含量从0.82%(原矿)降低到0.06%(磁选精矿),铁的回收率达到87%。采用XRD、SEM、EPMA等分析方法对焙烧产物进行脱磷机理研究。结果表明,在还原焙烧过程中,原矿中有20%的磷灰石生成单质磷随气体挥发,80%的磷灰石没有参与生成单质磷的反应,仍以磷灰石的物相存在于焙烧产物中,而通过磨矿磁选被脱除到尾矿中。磁选精矿中少量的磷以磷灰石的形态存在。在焙烧过程中,加入的脱磷剂与原矿中的脉石矿物(SiO2、Al2O3)反应生成铝硅酸钠,此反应部分破坏原矿的鲕状结构,充分改善焙烧产物中矿物的单体解离程度,有利于后续的磨矿磁选。     

Coupling relationship between multicomponent recovery of rare earth tailings

About 90%rare earth minerals and many other valuable minerals are heaped as iron tailings without comprehensive utilization.In order to comprehensively recover these valuable minerals,in a view of the valuable ore type of Baotou Steel tailing and embedded features,valuable components flow and their respective recovery coupling relationship in beneficiation flowsheet were analyzed;process flows and parameters which could give consideration to four kinds of components were determined.TFe,rare earth oxide(REO),niobium and fluorite recoveries could reach 72.70%,81.84%,78.58%and60.18%in low-intensity/high-intensity magnetic separation,respectively.High-intensity magnetic concentration was treated by REO direct flotation;the recovery is75.43%,on the base of which Fe could be separated completely from Nb.The underflow was treated by reduction roasting-low-intensity magnetic separation.And the relationship between the recoveries of these valuable components was also discussed.     

山东某含金磁黄铁矿浮选尾矿磁选回收试验研究

山东某含金磁黄铁矿原矿金品位1.60 g/t,硫品位1.86%,属含金硫铁矿。矿石性质研究结果表明,部分以磁黄铁矿为载体的金,矿物含量为0.96%,金品位8.25 g/t,原矿金分配率5.25%。生产流程对以磁黄铁矿为载体的金矿物的回收水平仍有提高空间。为了解决这一问题,开展了从生产原矿和生产尾矿中回收以磁黄铁矿为载体的金的对比试验,结果表明,磁选不宜用于原矿、重选不宜用于尾矿中载金磁黄铁矿的回收;尾矿磁选流程可以实现含金磁黄铁矿的有效富集,最终选择全粒级磁选工艺流程,获得了金品位1.52 g/t,硫品位2.87%的含金磁黄铁矿。尾矿金、硫回收率分别为52.09%、62.93%,对原矿回收率分别为12.27%、18.56%,实现了以磁黄铁矿为载体的金矿物的综合利用。     

铁锰多金属矿综合利用新工艺

以生物制剂KZSH01作为还原剂与铁锰多金属矿发生氧化还原反应,研究了铁锰矿的细度和还原剂的含量对还原效果的影响,考察了还原过程中温度和物相的变化,探讨了H2SO4用量对Mn和Zn浸出效果的影响.结果表明:生物还原剂KZSH01可使铁锰矿中93.0%MnO2转化为MnO,90.0?2O3转化为Fe3O4;Mn和Zn的浸出率均大于90.0%;Fe的磁选回收率大于85.0%,79.0%Pb和82.5%Ag富集在渣中.     

Application of suspension magnetization roasting as technology for high-efficiency separation of valuable iron minerals from high-iron bauxite

A technology for suspension magnetization roasting?magnetic separation was proposed to separate iron minerals for recovery. The optimum parameters were as follows: a roasting temperature of 650 °C, a roasting time of 20 min, a CO concentration of 20%, and particles with a size less than 37 μm accounting for 67.14% of the roasted product. The total iron content and iron recovery of the magnetic concentrate were 56.71% and 90.50%, respectively. The phase transformation, magnetic transition, and microstructure evolution were systematically characterized through iron chemical phase analysis, X-ray diffraction, vibrating sample magnetometry, X-ray photoelectron spectroscopy, and transmission electron microscopy. The results demonstrated the transformation of hematite to magnetite, with the iron content in magnetite increasing from 0.41% in the raw ore to 91.47% in the roasted product.     

Leaching kinetics of antimony-bearing complex sulfides ore in hydrochloric acid solution with ozone

The leaching kinetics of Sb and Fe from antimony-bearing complex sulfides ore was investigated in HCl solution by oxidation–leaching with ozone. The effects of temperature, HCl concentration, stirring speed and particle size on the process were explored. It is found that the recoveries of Sb and Fe reach 86.1% and 28.8%, respectively, when the reaction conditions are 4.0 mol/L HCl, 900 r/min stirring speed at 85 °C with <0.074 mm particle size after 50 min leaching. XRD analysis indicates that no new solid product forms in the leaching residue and the leaching process can be described by shrinking core model. The leaching of Sb corresponds to diffusion-controlled model at low temperature (15–45 °C) and mixed-controlled model at high temperature (45–85 °C), and the apparent activation energies are 6.91 and 17.93 kJ/mol, respectively. The leaching of Fe corresponds to diffusion-controlled model, and the apparent activation energy is 1.99 kJ/mol. Three semi-empirical rate equations are obtained to describe the leaching process.     

Ni-SiC复合电铸层内应力实验研究

提出通过掺杂SiC颗粒来减小Ni微电铸层内应力的新方法,基于UV-LIGA工艺制作了纯镍电铸层和Ni-SiC复合电铸层,采用X射线衍射法测量微电铸层的内应力,分析SiC颗粒对微电铸层内应力的影响效果。利用L_9(3~4)正交试验考查了铸液中SiC浓度、电流密度、搅拌转速及电铸温度等工艺参数对复合电铸层内应力的影响。结果表明:掺杂SiC颗粒能有效减小微电铸层内应力,电流密度和铸液中SiC浓度对内应力的影响大于搅拌转速和电铸温度。复合电铸层内应力实验的最优工艺参数为:SiC浓度20 g/L,电流密度1 A/dm~2,磁力搅拌转速600 r/min,电铸温度50℃。     

Comprehensive Utilization of Iron and Phosphorus from High-Phosphorus Refractory Iron Ore

An innovative process of coal-based reduction followed by magnetic separation and dephosphorization was developed to simultaneously recover iron and phosphorus from one typical high-phosphorus refractory iron ore. The experimental results showed that the iron minerals in iron ore were reduced to metallic iron during the coal-based reduction and the phosphorus was enriched in the metallic iron phase. The CaO-SiO₂-FeO-Al₂O₃ slag system was used in the dephosphorization of metallic iron. A hot metal of 99.17% Fe and 0.10% P was produced with Fe recovery of 84.41%. Meanwhile, a dephosphorization slag of 5.72% P was obtained with P recovery of 67.23%. The contents of impurities in hot metal were very low, and it could be used as feedstock for steelmaking after a secondary refining. Phosphorus in the dephosphorization slag mainly existed in the form of a 5CaO·P₂O₅·SiO₂ solid solution where the P₂O₅ content is 13.10%. At a slag particle size of 20.7 μm (90% passing), 94.54% of the P₂O₅ could be solubilized in citric acid, indicating the slag met the feedstock requirements in phosphate fertilizer production. Consequently, the proposed process achieved simultaneous Fe and P recovery, paving the way to comprehensive utilization of high-phosphorus refractory iron ore.     

矿浆浓度对金矿浮选速率影响的动力学研究

采用一阶浮选动力学模型对金矿石的浮选回收率进行了拟合,以研究矿浆浓度对不同粒径金矿浮选速率的影响。结果表明,浮选矿浆浓度与金的累积品位呈反比,而与金的累积回收率近乎呈正比,低浓度比高浓度矿浆更有利于金的高效富集,高浓度矿浆下更有利于金的回收。粗颗粒金比细粒级金更适应高浮选矿浆浓度体系,其浮选回收率及累积品位均更高。实际矿石试验验证了浮选动力学拟合结果,在50%的浮选矿浆浓度中,经闪速浮选协同常规浮选工艺,可以获得金品位50.0 g/t,回收率88.93%的金精矿,获得了比单一常规浮选更好的技术指标。     

磁性Fe3O4/活性炭对电镀废水中Cr(Ⅵ)吸附性能的研究

目的获得吸附性能、磁分离性能和再生性能较佳的磁性Fe_3O_4/活性炭吸附剂(MAC)。方法通过化学共沉淀法制备出磁性Fe_3O_4/活性炭吸附剂。采用X-射线衍射仪(XRD)和傅里叶变换红外光谱仪(FTIR)对活性炭进行表征。使用磁性Fe_3O_4/活性炭吸附电镀废水中的Cr(Ⅵ),考察吸附剂用量、吸附pH值和吸附时间对吸附性能的影响,并研究了吸附动力学模型。利用磁铁对磁性Fe_3O_4/活性炭进行了回收。结果制备的磁性Fe_3O_4/活性炭中含有纯度较高的立方相磁性Fe_3O_4粒子。在温度为25℃、pH=3、吸附时间为120 min、吸附剂用量为0.15 g时,对Cr(Ⅵ)的去除率最高,达到了97.44%,吸附动力学符合拟二级动力学模型。电镀废水中共存阳离子会使吸附性能增强,共存阴离子会使吸附性能降低。磁性Fe_3O_4/活性炭的回收率达93.58%,6次解吸-再生后,吸附量仍较高,为27.17 mg/g。结论磁性Fe_3O_4/活性炭吸附剂对电镀废水中的Cr(Ⅵ)具有较高的去除率,吸附剂回收方法简单,回收率高,具有较好的应用前景。     

Co-reduction of Copper Smelting Slag and Nickel Laterite to Prepare Fe-Ni-Cu Alloy for Weathering Steel

In this study, a new technique was proposed for the economical and environmentally friendly recovery of valuable metals from copper smelting slag while simultaneously upgrading nickel laterite through a co-reduction followed by wet magnetic separation process. Copper slag with a high FeO content can decrease the liquidus temperature of the SiO₂-Al₂O₃-CaO-MgO system and facilitate formation of liquid phase in a co-reduction process with nickel laterite, which is beneficial for metallic particle growth. As a result, the recovery of Ni, Cu, and Fe was notably increased. A crude Fe-Ni-Cu alloy with 2.5% Ni, 1.1% Cu, and 87.9% Fe was produced, which can replace part of scrap steel, electrolytic copper, and nickel as the burden in the production of weathering steel by an electric arc furnace. The study further found that an appropriate proportion of copper slag and nickel laterite in the mixture is essential to enhance the reduction, acquire appropriate amounts of the liquid phase, and improve the growth of the metallic alloy grains. As a result, the liberation of alloy particles in the grinding process was effectively promoted and the metal recovery was increased significantly in the subsequent magnetic separation process.     

吉林某金矿选矿工艺对比实验研究

对吉林某金矿进行了重选、无毒浸出和浮选3种选矿工艺对比实验,研究了磨矿细度、药剂用量、矿浆浓度等因素对选矿效率的影响.结果表明,无毒浸出工艺回收率为76.13％,重选工艺基本无优先选别作用;采用浮选工艺,在磨矿细度为-0.074 mm含量为90.52％,捕收剂异戊基黄药与丁铵黑药的药剂用量均为60 g/t,矿浆浓度为4...     

Recovery of iron from waste ferrous sulphate by co-precipitation and magnetic separation

Magnetite concentrate was recovered from ferrous sulphate by co-precipitation and magnetic separation. In co-precipitation process, the effects of reaction conditions on iron recovery were studied, and the optimal reaction parameters are proposed as follows: n(CaO)/n(Fe²⁺) 1.4:1, reaction temperature 80 °C, ferrous ion concentration 0.4 mol/L, and the final mole ratio of Fe³⁺ to Fe²⁺ in the reaction solution 1.9–2.1. In magnetic separation process, the effects of milling time and magnetic induction intensity on iron recovery were investigated. Wet milling played an important part in breaking the encapsulated magnetic phases. The results showed that the mixed product was wet-milled for 20 min before magnetic separation, the grade and recovery rate of iron in magnetite concentrate were increased from 51.41% and 84.15% to 62.05% and 85.35%, respectively.     

含铅锌难选铁矿石的矿物学及铅锌杂质产出特征

以新疆某含铁(FeT)47.04％、含Pb 0.39％、含Zn 0.30％的难选铁矿石为试样,采用化学分析、显微镜观察鉴定、EPMA和EDS等手段,考察其化学成分、铁铅锌的物相组成及铅锌杂质矿物的产出特征,探讨影响选矿工艺的矿物学因素与选矿前景.结果表明:含铁矿物中主要组合为赤褐铁矿、高达91.35％,少量磁性铁和硅酸...     

磁场诱导低维磁性碳材料对聚砜膜结构及流通特性的影响

目的 在膜的形成过程中，利用磁场力将亲水性磁性碳纳米材料吸引至膜表面，可以在膜表面附加亲水性和磁性，提高膜的渗透通量和截留率，改善膜污染问题。方法 将氧化石墨烯/碳纳米管混合溶液与Fe³⁺和Fe²⁺的混合溶液通入微反应器中预混合后，利用一步水热法引入四氧化三铁(Fe₃O₄)，制备具有优异磁性能的磁性碳纳米材料(MCN)，并将其共混于聚砜(PSF)基底中，采用磁场诱导非溶剂致相分离法(NIPS)制备磁性混合基质膜(PSF/MCN)。对MCN的形貌结构及磁性等进行表征，并通过改变PSF的浓度研究磁场作用下MCN的定向迁移对膜表面形貌结构及性能的影响。结果 亲水性磁性MCN的饱和磁化强度高达53.17 emu/g(1 emu/g=1 A·m²/kg)，表现出超顺磁性，且MCN在磁场作用下向膜表面定向移动。在相同的磁场强度下，不同聚砜浓度的膜表面表现出不同的形貌特征，并在聚砜的质量分数从15%升至17.5%的过程中，膜表面粗糙度的构成由细微密集的波动形貌转变为宽泛的浮动形貌。此外，MC...     

从失效有机铑催化剂中富集铑的新工艺研究

针对失效有机铑催化剂,利用还原-磨选工艺富集铑。在还原过程中,添加剂促进铁晶粒长大并富集铑,再通过磁选分离富集含铑的铁精粉。研究表明最佳工艺参数为:还原温度1200℃,还原时间6 h,添加剂配比10%,煤粉配比5%,球磨时间45 min,磁场强度1.28×105 A/m。利用X射线衍射对磁选铁精粉进行了分析,磁选后主要物相为金属铁、铑,除去了大部分脉石。最终得到铁精矿品位88.67%,回收率92.74%,铑回收率为92.08%。本工艺具有还原温度低、收率高等特点,为失效有机铑催化剂富集提供一种途径。     

废锂离子电池中集流体与活性物质的分离

针对废旧锂离子电池回收工艺中电极集流体的分离问题,根据集流体、活性物质、粘结剂的物理化学性质差异,对高温焙烧法、物理擦洗法和稀酸浸出-搅拌擦洗法分离集流体与活性物质进行研究。结果表明：高温焙烧与物理擦洗法都不能完全使集流体分离出来,而通过稀酸溶解-搅拌擦洗联合作用分离效果良好,在硫酸浓度为0.5 mol/L、固液比1：10、搅拌速度200 r/min、反应时间为40 min的条件下,可以实现正负极活性物质与集流体的分离,铝箔和铜箔可直接作为产品回收,只有极少部分进入浸出液,浸出渣用硫酸再浸,可以使钴、锂全部溶出,净化除杂后可回收钴和锂。     

Transformation of hematite in diasporic bauxite during reductive Bayer digestion and recovery of iron

The reductive Bayer digestion by using iron powder as reductant is proposed to convert hematite to magnetite and further to dissociate iron minerals from sodium aluminosilicate hydrate (desilication product, DSP) based on the differences of their surface properties. The results show that the differences of surface properties between magnetite and DSP in zeta potential, wettability and solvation trend facilitate magnetite to agglomerate, grow up and thus to dissociate from DSP. The increments of reductant amount and alkali concentration favor the transformation of hematite in digestion with the relative alumina recovery of 98.91%. Processing the resultant red mud can obtain qualified iron concentrate with iron grade of approximate 60% and recovery of about 86% through magnetic separation, resulting in reduction of red mud emission higher than 70%. The results are potential to develop a novel technology for processing high iron diasporic bauxite efficiently and provide references for comprehensive utilization of high iron red mud.     

还原剂对高磷鲕状赤铁矿直接还原同步脱磷的影响

讨论还原剂对鄂西高磷鲕状赤铁矿直接还原同步脱磷的影响,研究在固定脱磷剂用量下,还原剂用量对还原铁中铁、磷含量及铁回收率的影响,并研究其焙烧产物。结果表明:还原剂中固定碳及挥发分对还原铁中铁品位及铁回收率的影响较大,灰分对还原铁中磷品位的影响较大;当使用同一还原剂时,焙烧产物中金属铁含量随还原剂用量的增加而增加,浮氏体含量随还原剂用量的增加而降低,还原剂用量的增加会减弱脱磷剂与矿石中主要脉石矿物生成铝硅酸钠的趋势;当还原剂用量相同时,活性炭、焦炭、无烟煤和褐煤所得焙烧产物中金属铁含量逐渐增加,浮氏体含量逐渐降低;在这4种还原剂中,褐煤直接还原同步脱磷的效果最好,无烟煤和焦炭次之,活性炭的效果最差。     

Macrosegregation Behavior of Ti-10V-2Fe-3Al Alloy During Vacuum Consumable Arc Remelting Process

The effects of melting current and magnetic field in vacuum consumable arc remelting (VAR) process on the macrosegregation of Ti-10V-2Fe-3Al ingot are investigated in this paper. The results show that Fe content increases gradually from the bottom to the top of ingots along axial direction and the degree of macrosegregation is greater in the radial direction in the middle of the ingot versus the top and bottom. The macrosegregation rate of Fe element is higher with melting current of 2.6 kA than that of 1.7 kA in Ti-10V-2Al-3Fe ingot. There are two forces, buoyancy and Lorentz forces which arise from the flow of current through the pool of VAR when without magnetic stirring, but a new Lorentz force arising from the presence of external inductors occurs with adding magnetic stirring which decreases the macrosegregation rate of Fe element in Ti-10V-2Fe-3Al.