细粒浮选体系中颗粒间静电及范德化相互作用

本文系统研究了颗粒间范德华及静电相互作用，浮选剂的吸附对矿粒间范德华相互作用的影响，捕收剂在矿粒表面的吸附使矿粒间范德华吸引势能减小，起泡剂在气泡表面的吸附使矿粒与气泡表面范德华排斥能减小，根据ＤＬＶＯ理论，解释了矿粒在水中及稀电解质溶液中的凝聚行为。     

试论干式磁选的某些特点

强磁场磁选机的磁场梯度很大,因而磁场力Hgradh很不均匀。就单层感应磁极的强磁选机而言,磁场力随离开感应极的距离而迅速下降。在这类不均匀磁场中,由于不同粒度的矿粒对感应磁极(如齿极)的相对位置不同,所受磁场力差别极大。对微细矿粒来说,由于磁性物料和非磁性物料非选择性粘附,以混杂的集合体存在。无论这些集合体进入磁性或非磁性产品,对磁选指标都有不利影响。     

细粒浮选体系中颗粒间静电及范德华相互作用

本文系统研究了颗粒间范德华及静电相互作用，浮选剂的吸附对矿粒间范德华相互作用的影响。捕收剂在矿粒表面的吸附使矿粒间范德华吸引势能减小，起泡剂在气泡表面的吸附使矿粒与气泡表面范德华排斥能减小，根据ＤＬＶＯ理论，解释了矿粒在水中及稀电解质溶液中的凝聚行为。     

影响粉末流化的本征作用力及其调节

本文归纳了人们对粒间力的分析和计算，指出了影响颗是作用进而影响其流化质量的各种因素，并从改善微细物料流化质量的角度，综述了近年来国内外流化微细物料的诸多措施，将其旭结为两大类型：外力场方法与本征途径，以作为进一步探求微细物料流态化的研究基础。     

安徽铜山前山南矿段矿石工艺矿物学特征

通过对铜山前山南矿段的矿石进行工艺矿物学研究,查明了矿石的化学组成、矿物组成、矿石结构构造、主要矿物的嵌布特征以及金的赋存状态。金矿物以银金矿为主,少量自然金,主要包裹于黄铜矿、斑铜矿、辉铜矿中,形态不规则,微细粒。     

微细粒孔雀石乳浊液单纯矿物与赤铁矿浮选行为研究

本文研究了微细粒孔雀石乳浊液浮选行为。详细地考查了中性油种类、乳化剂种类、中性油与乳化剂配比,溶液 pH 等因素对浮选结果的影响,从而揭示了微细粒孔雀石乳浊液浮选基本规律。并给出了人工混合矿(微细粒孔雀石和微细粒赤铁矿)的乳浊液浮选分离结果。     

广西天等贫氧化锰矿石的选矿试验研究

天等锰矿石属高硅、低磷贫氧化锰矿石，矿物结晶粒度微细。选矿试验中进行了洗矿、强磁和重选流程研究，试验结果表明，洗矿效果较好，当原矿含锰１６．８５％，经一段洗矿后，可获得含锰２９．７７％，锰回收率为８６．２７％的锰净矿。     

安塞西区延长组长6储层孔隙结构特征及评价

根据岩心观察、岩矿薄片、铸体薄片及扫描电镜等分析结果,认为安塞两区长6油层组储层岩石以细粒长石砂岩为主,其次为中-细粒、中粒及粉-细粒、粉粒长石砂岩,该储层主要储集空间类型有沸石溶孔、粒间孔和粒内溶孔(长石溶孔、岩屑溶孔).主要的孔隙组合类型有粒间孔-溶孔型、溶孔-粒间孔型、粒间孔型及复合型等.研究区反映孔喉特征的各种参数变化较大,砂岩孔喉分布不均,孔喉配置关系主要为中孔-细喉型和小孔-微细喉型.     

1986—1987年国内外微细粒分选进展述评

微细粒物料的分选和处理一直是选矿研究的主要课题。近两年来,国内外在此领域的研究有增无减。对微细粒回收存在的问题、分选的某些途径及发展作了进一步的分析和评述。 为了从根本上解决物料粒径微细,用常规的选矿方法难以分选的问题,在如何利用矿粒的界面特性,通过适当的方法使微细物料增大其表现粒径的研究方面做了大量的工作。这些方法归结起来有选择性絮凝、剪切絮凝浮选、油团聚及载体浮选等。     

一种新型摇床面选别钽铌矿石的工业试验研究

研究微细矿粒和床面的表面电性的作用,并利用它们间对分选有益的作用,采取措施,来达到提高分选效率的目的是细粒重选的一个发展方向。试验采用自制的一种新型材质的波形床面进行钽铌选别的工业试验,获得了较好的选别指标,－０．０３８ｍｍ粒级钽铌精矿粒级回收率达到６１．７５％。     

Recovery of Fine and Ultrafine Mineral Particles by Electroflotation – A Review

Fine and ultrafine particles are successfully recovered by flotation when fine bubbles are present. Electroflotation is a technique in which fine bubbles are generated by the electrolysis of water. This article reviews the experimental studies into mineral recovery by electroflotation and the potential application of electrolytic bubbles in the recovery of fine and ultrafine mineral particles. The literature reveals that electroflotation resulted in better recoveries of ultrafine particles (e.g. dolomite, magnesite, and pyrite) as compared with dispersed-air flotation because electrolytic bubbles are smaller in size and are more active than those generated during dispersed-air flotation.     

电子显微技术在矿物材料研究中的应用

电子显微技术为矿物深加工、矿物材料制备过程中表征微观结构及物化特性提供了先进测试手段与科学的分析方法。本文介绍了电子显微镜测试技术在超细矿物粉体颗粒观测、矿物粉体表面改性、橡胶塑料填料、结晶学、粘土矿物学以及微生物矿物加工新技术中的应用。     

Recovery Improvement of Fine Magnetic Particles by Floc Magnetic Separation

The performance of floc magnetic separation (FMS) has been compared with wet high-intensity magnetic separator (WHIMS). This study was performed on low-grade iron ore slime contained 59.58% Fe with 4.57% silica and 3.78% alumina. Detailed characterization data indicated that a substantial amount of the slime was below 20 µm in size. Beneficiation studies indicated that the FMS process is effective to recover fine hematite and goethite particles, compared with the conventional magnetic separation. In conventional magnetic separation, the extent of the fluid drag force exceeds the magnetic force exerted on ultrafine particles. Thus, ultrafine magnetic particles were usually not recovered effectively by magnetic separators, resulting in the loss of valuable ultrafine slime particles. The FMS process significantly increases the magnetic force on the ultrafine iron ore in the form of hydrophobic flocs in a magnetic field, thus the ultrafine particles can be picked up effectively as magnetic concentrates. The FMS process improved the Fe recovery from 37.35% to 79.60%.     

Nanocrystalline Ni coatings strengthened with ultrafine particles

In this study, nanocrystalline Ni powders and thermally sprayed coatings, containing ultrafine AlN particles, were synthesized and characterized. The results indicated that the presence of AlN particles in the powders drastically decreased the dimension of agglomerates formed by cryomilling and increased the surface roughness of the agglomerates. The AlN phase was broken down into ultrafine particles of approximately 30 nm in size. These particles were dispersed in the Ni matrix and enhanced the development of a nanocrystalline structure in the Ni matrix during cryomilling. Selected-area diffraction patterns, obtained from transmission electron microscopy (TEM) and X-ray mapping with scanning electron microscopy (SEM), confirmed the presence of AlN particles in the coatings. The presence of AlN particles also led to an increase in the amount of NiO phase that was distributed in the coating, in the form of ultrafine, round particles. AlN particles increased the microhardness of the Ni coating by approximately 60 pct. Indentation-fracture results also indicated that the fine, dispersed AlN particles raised the apparent toughness of the Ni coating. The synthesized Ni coatings containing ultrafine AlN particles were characterized as equiaxed nanocrystalline grains with an average size of 24 nm, in which twins were observed. The increase in microhardness resulted from both grain refinement and the presence of ultrafine particles. The latter played the primary role in strengthening.     

超细粉末的组织结构分析：高分辨电镜的应用

介绍了超细粉末组织结构研究中高分辨电镜的应用现状和存在的困难;给出Fe超微颗粒的组织结构和高分辨点阵图象;指出高分辨电镜的应用,将提供有关超细粉末组织结构的重要科学信息。     

Recovery Enhancement of Ultrafine Wolframite through Hydrophobic Flocs Magnetic Separation

The recovery of ultrafine wolframite (<10 μm) by using flocs magnetic separation was investigated. Magnetic-separation results showed that recovery was closely correlated with the particle size of wolframite, where ultrafine particles were difficult to capture. Hydrophobic particles induced by octyl hydroxamic acid (OHA) could generate flocs, which enlarged the apparent size of particles. Furthermore, the recovery of ultrafine wolframite by flocs magnetic separation was higher than that by conventional magnetic separation. These findings indicated that the recovery was related to the increase in the magnetic force due to the particles’ size induced by hydrophobic flocculation.     

Zeta potential of the surface of ultrafine sulfides and floatability of minerals

The results of experimental investigations into the zeta potential of ultrafine sulfides (chalcopyrite, tennantite, galenite, sphalerite, pyrite, and pyrrhotine), the floatability of monomineral fractions of sulfides of the floatation coarseness (–0.1 + 0.05 mm) in a mechanical flotation machine, and the floatability fine particles of sulfide (–0.044 + 0.010 mm) in the Hallimond tube are presented. The preparation procedure of ultrafine powders and sulfhydril collectors to measure the zeta potential is presented. Zeta potentials of the surface of mineral particles and insoluble forms of sulfhydril collectors are investigated in the pH range from 2.0 to 12.5 (an acidic medium was formed by using H₂SO₄ and basic one by using NaOH or Ca(OH)₂), and various values of zeta potentials are found for sulfides in the sodium hydroxide and lime medium. Zeta potentials for all sulfides are negative in the NaOH medium at pH > 9.5, they are positive (1–18 mV) in the Ca(OH)₂ medium at pH > 11, and zeta potentials for chalcopyrite are positive in the studied range \(p{H_{Ca{{\left( {OH} \right)}_2}}}\) 9.0–12.5. The values of the isoelectric point in the medium of sulfuric acid and sodium hydroxide are as follows: for chalcopyrite—pH 6.5 and 8.8, for tennantite—pH 3.0, for sphalerite—pH 5.1 and 6.4, for pyrite—pH 3.1 and 8.9, and for pyrrhotine—pH 7.0. In the lime medium, the value for tennantite and sphalerite pH 12.0, for galenite—pH 11.2, for pyrite—pH 9.5 and 11.2, and for pyrrhotine—pH 9.5 and 12.1. Measurements of zeta potentials of ultrafine sulfide particles give the opportunity to refine the interaction mechanism of sulfhydril collectors with sulfides and associate the nonselective recovery of final tailings of sulfides in the highly alkaline lime medium with the contribution of the electrostatic component during the adhesion of ultrafine sulfide particles on bubbles and their mechanical carryout into the froth product.     

Thermodynamic Stability of Ultrafine Monodispersed Colloidal Particles of Basic Yttrium Carbonate

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Effect of colloidal agents in iron ore pelletizing

ABSTRACT

Organic binders have been used to replace bentonite in the pelletizing process of iron ore. In this research, colloidal agents were evaluated in a pelletizing process comparing their influence with the behavior of Peridur® and bentonite. Bench tests were carried out to identify the effects of binders and dispersant on the dispersion degree of mixtures, and their influence on the liberation/flocculation of fine particles. The results show that the dispersant acts on the fine particle content of the iron ore by removing ultrafine particles that are adhered to the surface of coarse particles, making the ultrafine available to the medium.     

超细金属颗粒的特性和应用

按当今新观点,将超细颗粒分成三个等级来处理,以澄清世上一些对其命名和概念所引起的混乱状况。通过对其表面效应、体积效应(包括量子尺寸效应)及对原子簇幻数结构的详细描述,可释明超细金属颗粒之所以具有不同于一般块、粒状金属的诸多特异性能。还着重介绍了超细金属颗粒在宇航、原子能、军事、电子、化学、冶金等工业及医学、生物工程方面的最新应用成果。