Search Documents

By Frank van der Meer, Lea Quincke

"High Pressure Grinding is applied to achieve size reduction of the particles by inter-particle breakage and to generate micro-cracks in the product particles as a contributing factor in e.g. leaching or mineral liberation. As alternative to classification, a closed circuit operation for HPGR can be established by product recycling, where a proportion of the coarser edge material and parts of the center material are split-off to be recirculated to achieve a finer final (center) discharge product for subsequent processing steps as ball mill grinding or beneficiation. As a result of the product recycling, the content of fines in the feed material increases and may affect the grinding efficiency in terms of production of fines and the generation of micro-cracks in the particles. In the scope of this paper, the effects of the proportion of fines in HPGR feed on grinding efficiency and micro-crack generation were evaluated. Grinding tests were executed with different feed size distributions, from a fines-void situation (truncated feed) to a fines-abundant situation (high product recycle). The evaluation of grinding efficiency and generation of micro-cracks was done by particle size analysis, Bond Work Index tests, impact tests on HPGR feed and products, and X-ray computed tomography of single product particles. This publication summarizes the main aspects of the outcome of these investigations."

Jan 1, 2014

By A. Mainza, H. Hill, L. Bbosa

"The main objective of ore breakage characterization is to quantify the relationship between the energy supplied for breakage and the size of the resultant progeny. In this study, the ore breakage characteristics of drill core particles and crushed particles were compared. Single impact breakage tests were conducted on a basalt ore sample using the JK rotary breakage tester. The size-dependent model by Shi and Kojovic was used to fit the breakage data because the effect of initial particle size is accounted for in the model. It was found that crushed particles consistently gave a higher degree of brokenness than drill core particles and the differences were attributed to the internal structure of the particle. Drill core particles contain a lower crack density (paths of weakness) than crushed particles which have been pre-weakened during the crushing process. An increase in crack density is directly related to a decrease in the minimum threshold energy. Upon application of a stressing force above the stress threshold, particles with a higher crack density will fracture more easily because of a higher rate of crack propagation due the numerous paths of weakness available. It was therefore concluded that under the same conditions, drill core particles are more competent than crushed particles. INTRODUCTION Comminution devices have commonly been reported as being the largest energy consumers in mineral processing circuits (Napier-Munn, 2015). Cleary (1998) reported that the inefficiency of comminution devices is a result of less than 5% of the supplied energy being utilized for breakage, with the majority being expended as heat and noise. With steadily declining fossil fuel supplies and a looming global energy crisis, the mineral processing industry has increased its focus on energy reduction measures. Ore breakage characterization plays a critical role in the design and optimization of comminution circuits (Tavares and King, 1998). The main objective of ore breakage characterization is to empirically quantify the relationship between the energy supplied for breakage (specific input energy) and the size of the resultant progeny through laboratory particle breakage tests (Napier-Munn, 1996). Commonly used laboratory breakage devices include the Drop Weight Tester (DWT), Split Hopkinson Pressure Bar (SHPB) and more recently, the JK Rotary Breakage Tester (JKRBT). Typically, a standard single impact breakage test procedure consists of a matrix of experiments on particles in four to five narrow size fractions each tested at low, medium and high energy levels. The resultant progeny of each test is sized to obtain a particle size distribution (PSD) from which the degree of breakage, usually in the form of a t10 value (percentage of the progeny material that passes 1/10 of the feed size) can be obtained for each size fraction and energy level (Napier-Munn, 1996)."

Jan 1, 2018

By Mahdi Shevrini, Hamed Haghi

"In this research, the operation of screen classifying in silica processing circuits was investigated and modified by replacement of available trommel screens with teetered bed separator (TBS). In addition the effect of the mentioned replacement and addition of attrition scrubber on quality of final product, impurities removal, recovery and production rate were inspected. Considering screen efficiency problems to achieve certain particle size distribution, hydraulic classifying system was selected instead of trommel screens. Application of suggested plan improved quality and particle size distribution of produced silica significantly. Optimization of size classification in process circuit resulted in increase in production rate up to 21% (from 67% to 81%), silica recovery (from 68.35% up to 83.11%) and relative enhancement in removal of impurities such as Fe2O3 and TiO2. After optimization and stabilization of grinding and size classification section, industrial attrition scrubbing tests were carried out and the best solid percent and retention time were determined i.e. 70% and 6 minutes, respectively. Using sodium carbonate during attrition scrubbing, has major effect on removal of surface coating and staining especially sharp increase in clay removal; therefore 2 kg/t of sodium carbonate can be optimistic point of industrial procedure for this silica processing plant. It should be mentioned that application of attrition scrubbing which is followed by screw classifier for de-sliming were useful for better cumulating of particles in the range of appropriate liberation degree (+106-300µm) and efficient removal of metallic (iron and titanium oxides) and non-metallic (clays and feldspars) impurities."

Jan 1, 2014

By Robert Snow, Shibo Zheng, Wenyi Song, Xiaoqing Ma, Patrick Zhang

Numerous phosphate mineral depressants have been reported in the literature for use during anionic flotation of dolomite from carbonate fluorapatite in slightly acid circuits. In one part of this research, laboratory flotation experiments were conducted to compare the effectiveness of phosphate depressants to process ground, deslimed high-MgO Florida phosphate pebbles. Ten potential phosphate depressants were evaluated during laboratory anionic flotation of dolomite from phosphate in a slightly acid circuit using a sulfonated oleic acid soap plus oil as the dolomite collector. Eight of the depressants have been used by various investigators with foreign and domestic carbonate-phosphate ores. Four of the depressants were found to be reasonably effective during the current flotation study, namely: sodium tripolyphosphate (STPP), sodium hexametaphosphate (SHMP), tetrasodium pyrophosphate (TSPP) and diphosphonic acid (DPA). Without depressants, the sulfonate collector required to produce cell underflow phosphate products containing <0.80% MgO and MgO/ P2O5 ratio <.033 was 1.13 kg/ton of flotation feed at a flotation pH range = 5.5-6.0. Using this collector level with 0.91 - 1.36 kg/ton of feed of STPP, SHMP or TSPP yielded phosphate products analyzing 0.73-0.92% MgO and MgO/ P2O5 ratios = .027-.034 at 90.0-96.8% P2O5 recovery. Similar grade phosphate products were obtained using DPA as the phosphate depressant at 84.1-87.5% P2O5 recovery. When no depressant was used, a similar grade phosphate product was obtained at only 65.9% P2O5 recovery. Another part of the research aimed at reducing MgO content in the final concentrate from Florida phosphate plants by conducting dolomite flotation on the final concentrate. Numerous phosphate depressants were tested for this purpose, including acidic, neutral and alkaline reagents. The most effective phosphate depressant was found to be phosphoric acid, giving both high grade and recovery.

Jan 1, 2014

By F. Z. Dong

The paper is mainly about a study on the techniques of separating iron from pyrite cinder of a certain sulfuric acid plant in Shandong province. The main components of the cinder are Fe2O3 and SiO2, and the degree of liberation of iron mineral and gangue is very high. So the iron concentrate with higher degree of iron and lower grade of silicon and sulfur can be achieved by reverse flotation. The iron grade of the concentrate reaches 63% and the recovery of iron is no less than 63%. And the most important influencing factor of the flotation is the temperature of the pulp. A better guideline can be achieved by magnetic separation. The cinder is magnetizing roasted for 15 minutes with temperature of 800?, and the concentrate with the iron grade 64%, sulfur grade 0.2% and iron recovery 85% can be obtained by two stage magnetic separation. A rotary kiln has been built to deal with the pyrite cinder, and the result of the industrial magnetizing experiment and magnetic separation is satisfying.

Jan 1, 2014

By A. O. Gapchich, T. N. Matveeva, N. K. Gromova

"Tin sulfide ores and aged man-made products obtained after their processing are distinguished by a complex material composition and uneven impregnation of sulfide minerals (chalcopyrite, galena, arsenopyrite, etc.) and tin ore (cassiterite). Enrichment of such ores is performed through sophisticated multistage schemes using not only gravitational methods, but also gravity flotation, flotation, magnetic separation techniques. Tin ores also contain rare and precious metals (indium, scandium, silver), characterized by fine dispersity and microscale to nanoscale fineness of mineral formations. During flotation concentration these metals are extracted along with the main ore minerals into concentrates (tin, copper, tungsten, etc.), however, up to 10-20 % of them are lost with final tailings. The aim of the work is an experimental study of the modification of the surface of sulfide minerals and cassiterite by stable metal-collector complexes to increase extraction of fine tin, silver, copper and other metals from complex tin ores. Triamide cyanuric acid (TCA) was studied as a thin silver flotation modifier. Thermophilic polymer with a functional group of phenylphosphine TMPPh was used as a selective flocculant. For experimental studies of the physical and chemical effects of collecting agents on the surface of minerals the following analytical techniques were used - the analytical scanning electron emission ASEM (LEO 1420VP INCA OXFORD ENERGY 350) and laser (KEYENCE VK-9700) microscopy, measurements of electrode potentials of mineral anthills by potentiometric titration, monomineral and pulp flotation. New data on formation of the adsorbed layer of DBDTC on the surface of chalcopyrite, galena and arsenopyrite were obtained, and the dimensions of the reagent films and the strength of their adsorption. The indiscriminateness of cassiterite to DBDTC ensures its selective separation into a chamber product during the flotation of sulfides. It is shown, that modification of the sulfide surface by stable complexes Me-DBDTC and Ag-TCA-TMPPh will increase the recovery of non-ferrous metals and silver into a collective sulfide concentrate and will provide a high-quality tin concentrate for flotation of tin sulfide ores.The studies were perfomed with the aid of the Russian Science Foundation (Project No. 17-17-01292).INTRODUCTIONTin sulfide ores and aged man-made products obtained after their processing are distinguished by a complex material composition and uneven impregnation of sulfide minerals (chalcopyrite, galena, arsenopyrite, etc.) and tin ore (cassiterite). Enrichment of such ores is performed through sophisticated multistage schemes using not only gravitational methods, but also gravity flotation, flotation, magnetic separation techniques. Tin ores also contain rare and precious metals (indium, scandium, silver), characterized by fine dispersity and microscale to nanoscale fineness of mineral formations. During flotation concentration these metals are extracted along with the main ore minerals into concentrates (tin, copper, tungsten, etc.), however, up to 10-20 % of them are lost with final tailings. In this regard, it seems advisable to use new varieties of flotation reagents in order to increase extraction of finely dispersed tin, silver, copper and other non-ferrous and precious metals from multi-metal tin ores (Bocharov and Ignatkina, 2007; Khanchuk etal., 2012; Wu and Zhu, 2006; Yusupov etal., 2016)."

Jan 1, 2018

By A. Makavetskas

"The purpose of the research is to study the mineralogical features of the structure of the wall accretion formed during melting on the working surface of the walls of metallurgical aggregates and adversely affect the stability of the lining of blast furnaces (BF). We presented the results of studies of the material composition of lining and wall accretion of the furnaces of blast furnaces of the metallurgical plant specializing in the smelting of ferromanganese, nodular and pig iron. It is established that the garnissage is an aggregate of layered texture, formed as a result of the crystallization of slag and metallic melts. Refractory calcium and magnesium silicates and aluminosilicates (minerals of the melilite group, leicite, olivine group minerals) and amorphous glassy oxide solid solutions of variable composition crystallize from the slag melts in the upper part of the hearth. In the slag matrix, inclusions of carbon (amorphous and graphite) and products of crystallization of metallic melts of alpha-iron, iron carbides and / or manganese are observed. Evidence of carbon evolution (in the form of graphite) is precisely in the crystallization of metal melts, there are significant differences in the structure of carbon in coke and in the garnissage. The conducted studies confirm that it is impossible to obtain reliable information on the material composition of new formations in the blast-furnace process without using a complex of modern methods of technological mineralogy.INTRODUCTION The formation of the wall accretion (garnissage) - a solid protective layer as a result of smelting products crystallization on the inner (working) surface of the liner. This is due to the design of blast furnaces with a high-efficiency heat sink using copper coolers and the use of carbon blocks with high thermal conductivity in the lining. The objective of the study was research of the material composition of the lining and wall accretion of the blast furnace hearth of one metallurgical plant that specialized in smelting ferromanganese, nodular and pig iron, to assess the effect of new formations for stability of the lining of blast furnaces (BF)."

Jan 1, 2018

By G. Semenchenko

Heterotrophic microorganisms Pseudomonas aureofaciens, microscopic fungi Fusarium sp. and their combinations with some chemical substances were used for gold leaching from refractory ore and flotation concentrateof Akbakaj deposit. All biological additives raised the speed of noble metals dissolution. The best results of gold extraction from ore were in the presence of bacteria or their associations with other solvents and from flotation concentrate in the presence of fungus - 30 % of additional amount of gold. The maximum extraction of gold speed value was during the first 8 hours of process. The electronic-microscopic researches of the ore samples showed almost complete decay of pyrite and arsenopyrite under bacteria influence whereas at chemical leaching most of these minerals stayed uncrushed. The presence of microscopic fungi in flotation concentrate during leaching provided full distraction of pyrite, but some crystals of antimony and arsenopyrite were undestroyed. During cyanide leaching of flotation concentrate there were accumulation of antimony and incomplete pyrite decomposition. Keywords: gold bioleaching, bacteria, fungi, complex solution

Sep 1, 2012

By E. V. Zelinskaya, A. E. Burdonov

"In the raw aluminum production processon electrolyzers with self-baking anodes, during technological operations, flow-regulated treatment and adjustment of the electrolyte chemical composition produced by diesel and floor-rail technology, alumina and fluoride salts are spilled through the ventilation grilles of the electrolysis body aeration channels, leakage in the equipment, machinery and motorized machinery construction elements. As a result of this, a part of the bus station and the level of ± 0 (the basement room with supporting curbstones and columns, on which electrolyzers are installed) are covered with technological raw material. This leads to an increase in the conductor (bus) resistance, contact connections deterioration, cell insulation failure and raw materials loss. For example, at the enterprise ""Rusal-Bratsk"", as a result of the activity, up to 420 tons per month of alumina-containing wastes that are unfit for use in the electrolysis process are formed due to the alumina substantial contamination with salts of iron and silicon, which significantly reduces the technical and economic parameters of the electrolysis process. The main scientific problem is the processing (cleaning) of alumina-containing waste having a complex mineralogical composition of the material, its contrast and structure, from oxides of iron and silicon, using ""dry"" separation methods. In the performing the work process, qualitative indicators of the influence of external factors (air humidity, precipitation, sunlight, temperature difference) on the physicochemical processes components interaction during the raw materials storage are established. On the basis of laboratory tests, it is established that alumina-containing raw materials can be separated and photometric and gravitational separation methods used. A mathematical model of the motion of particles of primary and prepared alumina-containing raw materials in a cascade-gravity classifier was developed. The criteria and factors characterizing the alumina-containing material, as well as influencing and determining the maximum material enrichment, are established."

Jan 1, 2018

By Kari Moen, John Rasmus Leinum, Jarle Hjelen, Terje Malvik

"Automatic identification and characterisation of mineral raw materials and beneficiated products are of major importance in mineral processing. However, minerals show great variety in their composition and physical and chemical properties. Industrial minerals may contain the same elements in about the same amount. In these cases backscatter electron imaging or chemical analysis are not sufficient to identify the minerals. Another problem arises when micro textures are not detectable in traditional imaging or the grain size is smaller than the X-ray spatial resolution.As a supplementary technique in these cases, application of crystallographic information by electron backscatter diffraction (EBSD) in the scanning electron microscope (SEM) may be a suitable method. By means of EBSD, diagnostic mineral information can be achieved if indexible patterns are provided.Until now EBSD has not been used frequently on geological samples for mineral and micro structure discrimination.The technique has been demonstrated on three Norwegian mineral raw materials and one Italian marble and shows that it has some advantages compared to traditional techniques."

Jan 1, 2003

By H. R. Manouchehri

"In mining and minerals industry, except profitability, there are some crucial factors that represent components in economic machinery of a mine and related activities. These are sustainability and minimizing environmental impact factor. Environmental concerns combined with the water and energy availability and related costs, as well as public license to operate all contrive to demand for more efforts targeting sustainability. Mining industry is highly energy-intensive (estimated to consume 6-7% of total world’s energy), with varying the energy efficiency across the industry resulting in significant costs. Size reduction is the main energy consumer contributing to almost 50% of the total energy used in mining. That means efforts must be made to introduce energy efficient comminution flow-sheets and machineries for sustainable development. Since the crushers are more energy efficient than mills, it is logic to push down-sizing in crushing stage(s) as far as technically possible. That has been strategy for Sandvik Mining and Rock Technology in supplying advanced and effective crushers to provide fine crushed product for subsequent milling stage. Lowering the energy consumption and related costs as well as increasing throughput have been the main objectives in design and development of comminution circuits and related machineries. Inefficiency in comminution technology, particularly in grinding, has long been regarded as a major area for investigation and development, especially when production of fines and ultra-fines are considered. In an attempt to explore the potential of fine crushing and its effects on subsequent milling process the fine crushing performance of Sandvik’s conventional cone crusher and Vertical Shaft Impactor (VSI) in pilot scale to define the energy consumption and circulating load in fine crushing. Tests were conducted to obtain fine crushed products at P = 2 mm in a close circuit. Furthermore, the crushed products were characterized and compared by grind-ability, morphology, and surface area measurement tests. Finally, the energy consumption to grind the crushed products to specific grind size was calculated."

Jan 1, 2018

By R. L. Pascual, W. J. Whiten

"The froth flotation process is not well understood. Both flotation models, and the parameters used to describe the stream flows are not well defined. They in fact vary considerably in different applications. This creates difficulties is designing a simulation program suitable for use by plant personnel, consultants, and researchers. In addition to simulation, an effective simulation program can be expected to provide a range of other services.This paper shows how a process circuit simulator can be designed with sufficient flexibility to satisfy these needs, and discusses some of the additional services."

Jan 1, 2003

By A. Usov

The studies carried out by the Russian researchers and those carried out jointly within some contracts with scientific organizations and companies of other countries, show that the electric pulse disintegration of materials (ED), proposed and investigated in detail in Russia (Kalyatsky, et al, 1980; Usov et al, 1987; Semkin et al, 1995; Usov and Tsukerman, 2000; Kurets et al, 2002) has been widely recognized and developed abroad (Andres, 1995; Inoue et al, 2000; Biela et al, 2008). The Russian and international journals and the proceedings of the conferences dealing with the electric pulse disintegration pay great attention to the principal principals of selective disintegration of materials. There is no, however, any information concerning both the technical means developed to implement the technique and the assessment of their performance, which would be necessary in objective assessment of the industrial use of the technology. The results of long-term studies of the technique and technologies of electric pulse disaggregation by research institutes such as Research Institute of High Voltages (Tomsk), Kola Science Centre of RAS (Apatity), Institute "Mekhanobr"(S.Pertersburg) described. Exploratory stands and technological installations are developed to carry out pilot tests and operations under production conditions. Basic circuits and classification of technical means electric pulse disintegration of the materials are proposed, the analysis of transportation schemes and classification of the material in the disintegration apparatus are given, construction of chambers for continuous stadial disintegration of ores and materials are presented. The features and technological efficiency of electric pulse disintegration of various types of ores, and the spheres of effective use of the method have been determined. Keywords: electropulse disintegration, disintegration machines, chambers of comminution, stadial comminution.

Sep 1, 2012

By A. Bahrami

Andalusite, silimanite and kyanite are polymorphs of aluminosilicate known as kyanite group. Minerals of this group are used in refractory. Sarband andalusite deposit is located in Markazi province in Iran. Mineralogical studies showed that the main minerals of this sample are andalusite (5%~10 %), mica, quartz and feldspar. Processing of the samples was carried out using two sizes, i.e. +500 µm and -500 µm. In the processing of +500 µm scrabble test was carried out on -4750 +500 µm and -2380 +500 µm. For -500+300 µm shaking table and magnetic separation were applied. For -300 µm fraction, flotation was carried out. The results of this tests showed that the processing of Shazand andalusite was not possible, because silica and iron impurities were diffused inside the andalusite mineral grains.

Jan 1, 2014

By M. A. C. Goes

Over the last twenty years CETEM has been involved in the preparation and certification of reference material from ores, concentrates and related materials for use in analytical laboratories associated with mining, metallurgy and earth sciences. CETEM provides reference materials from mineral samples, not available from the existing sources, to meet the needs of the mining and mineral industry. CBPA-1 and CBPA-2 respectively are samples of copper sulphide ore and flotation concentrate, both originated from Sossego Mine, located in Pará State, Brazil. The batch characterization was carried out by a collaborative measurement program with participation of 20 industrial, commercial and government laboratories from South America, North America, Europe, Asia and Africa. The certificates and report were issued in December 2007 (http://www.cetem.gov.br/ mrc/ing). The objective of this paper was to describe the procedures for material preparation and the collaborative approach involving a collaborative interlaboratory measurement program to certify CBPA-1 and CBPA-2.

Jan 1, 2014

By H. Tiefel, M. Schneider, T. Neesse, J. Regler, J. Dueck, F. Donhauser

In practice the advantages of high-quality hydrocyclone separation are often reduced due to varying feed suspension properties, solids concentrations and particle size distributions. Control systems of large hydrocyclones are usually fitted with controllable underflow nozzles, which is not practical for small hydrocyclone batteries. Therefore, a new control system for a battery of hydrocyclones with a nominal diameter of 150 mm was invented at the LUR in cooperation with AKW Apparate und Verfahren GmbH & Co. KG. This process was developed for bentonite slurry regeneration associated with tunnel excavation using bentonite slurry as a transport aid and lubricant.

Jan 1, 2003

Results of the study of chloride ion concentration effect to osmium-187 sorption from wastewater of copper smelter with use of foreign anionites of different basicity and structure are presented in the work. It was found that the increase of chloride ion concentration in the wastewater helps to increase recovery of osmium using anionites regardless of their nature. The ways to intensify the process are proposed. The method for osmium elution from the anionites with potassium iodate solution was developed. It was shown that the method lets to recover up to 99% of osmium from the anionites. Recommendations for selection of eluents for better recovery of osmium from the anionites were elaborated. Keywords: wastewater, osmium, anionite, sorption, chloride ions, eluent, recovery

Sep 1, 2012

By R. C. Miranda

Flotation is an operation widely used in mineral processing because of its aptitude to recover minerals of interest very efficiently. Flotation is often responsible for making possible the exploitation of mineral deposits of low concentration. In flotation various processes phenomena occur, some of which have still not been explained scientifically. Due to this fact, there are no models that can be widely applied in flotation control. Thus, in most cases, the control is done by experienced operators who are able to visually classify the types of foam into different categories and each one of them is associated with an operating actuation. In this situation, image analysis is configured as a solution that has already been employed in several ways. In this paper, a control strategy based on the colour of froth on a direct flotation of a nonferrous metal is presented. Moreover, the paper reveals the theoretical basis of the method, the critical points, difficulties and improvements that can be implemented. Data of grade were collected from the mineral of interest and RGB (red, green and blue) data of final concentrate of the froth. The mineral grade was collected and analysed during one month of operation and RGB was obtained using a camera. It was verified that the red colour showed the same trend of the grade curve in the concentrate. Thus, the use of this online data in optimising control was introduced. The laboratory grade is used to calibrate the colour set point. Therefore, it was possible to monitor in real time the trend of enrichment and depletion of a non-ferrous mineral in a flotation. It was possible to establish an online control strategy based on simple data acquisition. The result was an increase of 10% on production.

Sep 1, 2012

By D. Johann, E. Zanetti, I. A. S. Brum, P. M. Zancan, A. F. Castro

"This study was done from a sample of coal mined at the Vale-Mozambique mine, located in Moatize district, Tete Province. The aim of this work is to analyze the reagent system in the flotation of coal fines belonging to the Upper Chipanga layer (UC). Among coal processing methods, flotation stands out as one of the most important for the concentration of this material, in particular in the treatment of fine particles. The total feed of the Vale-Mozambique processing plant is 8,000 tph of coal, where 10% of this feed corresponds to the fine fraction that feeds the flotation circuit. The material used in this study had a particle size of 96% smaller than 0.25 mm. The reagents used in the flotation tests were betacol and diesel oil as hydrophobizing agents and MIBC as frother. The range of betacol concentrations in the first test phase was 200 g/t to 500 g/t, and in the second phase 200g /t to 500g /t while diesel oil and MIBC were kept constant at 300 g/t. The immediate analysis followed the Brazilian standards NBR 8289, NBR 8293, NBR 8290; and NBR 8299. The results showed that it is possible, from a feed with ash content around 22.84%, to obtain products with levels below of 10% ash, with a mass recovery around 50%. The recovery of carbonaceous matter was also evaluated and presented positive results. Complementing this study, the effect of H2O recovery was evaluated and it was observed that for the concentrations of betacol the recoveries ranged from 6 to 9%, and for diesel oil plus MIBC were 4 to 7%.INTRODUCTION Considering the increase in population and energy consumption as humanity has been living along the last decades and the consequent demand for non-renewable natural resources, it is clear the challenge of the mineral industry in the search for new technologies and improvement of the existing ones. This challenge is justified by the need for better industrial results and to meet the market specifications, taking into account the reduction of deposits with higher contents and the need for beneficiation of more complex ores, lower levels and lower release granulometry. Usually in these situations, processes already well-established as the gravimetric (Sampaio and Tavares, 2005) have not good results."

Jan 1, 2018

By Robert Dunne

A review of the current ?state of the art? of refractory gold treatment will be provided. This will include a global perspective of the refractory processes that are being practiced, where they are and some discussion on why the processes were selected. Some discussion on the challenges that face the refractory gold industry will also be provided.

Sep 1, 2012