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"The business importance of water for mining companies is unequivocal as it may affect several aspects of mining projects ranging from the life-and-death license to operate to the imperative economic viability. It is thus no wonder that nearly all mining companies acknowledge water-related risks, issues and opportunities in their respective sustainability report. Somehow, this procedure has fostered the idea that water frugality could be the sustainable solution to several water-related issues. The regular exercise of water accounting should then follow as a key strategic requirement. Water accounting is defined as the application of a consistent and structured approach to identifying, measuring, recording and reporting information about water. However, several factors discussed herein have led to the fact that some water accounts are still produced using means (hardware and software) which undermatch the value actually associated with water. The resulting fuzziness about water usage could result in missed opportunities, suboptimal operations or even lead to environmental law violations. This paper subscribes to the distinctive perspective that, once underlying concepts and practical definitions have been standardized under a supported framework, such as the openly available Water Accounting Framework (WAF) published by the Minerals Council of Australia, most of the remaining water accounting issues may be boiled down to accuracy issues and, ultimately, to how much accuracy is valued by the stakeholders. Using the latest WAF document as a baseline for best practices of water accounting and, borrowing concepts from the fields of sensor network design in the process industries and best practices of metal accounting, this paper reviews some essential accuracy issues to be considered when designing or analyzing water accounting systems in mineral processing. The current paper also includes some elements for a promising attempt to include the value of information paradigm inside the water accounting best practices."

Jan 1, 2014

By A. Deepatana

This study compares the use of an aminophosphonate chelating resin Purolite S950 and a sulphonic acid strong cation exchange resin Purolite C160H to recover nickel and cobalt from the synthetic bioleach solutions. Batch adsorption of metal citrate is performed as a function of metal citrate concentration (15~2000 mg/L) and solution pH (0.01M and 0.1M citric acid). The adsorption mechanism as inferred from the fit to Langmuir (LM), Freundlich (FM) and Redlich-Peterson (RP) models demonstrates that nickel citrate adsorbed onto C160H appears monolayer in comparison to that adsorbed onto S950 exists multilayer. In contrast, cobalt citrate adsorption onto both C160H and S950 agrees with the LM model. The results have shown that loading capacities of nickel and cobalt citrate onto C160H are 60 and 65 mg/g whereas those observed onto S950 are 16mg/g and 6 mg/g respectively. These are achieved in metal citrate prepared in 0.1 M citric acid. Resin regeneration is conducted in using 2 M nitric acid solution. The results show high efficiency of nickel and cobalt citrate elution from Purolite C160H. Findings from this study suggest Purolite C160H is a suitable adsorbent for recovering nickel and cobalt from bioleaching solutions.

Jan 1, 2014

By H. G. Hedlund

Tailings in Mining Industry can be handled in different ways. Today tailings disposal is in focus by projecting new plants as well as treating and handling of old Tailings dams.The trend today is to process minerals, detoxify the Tailings and place them as dry surface Deposition or Underground Backfill. This paper will briefly present five different Mining plants in North and Central America, where Tailings have to be dewatered for dry depositing. The Metso-Sala VPA is a filter especially developed for dewatering and drying of Mineral Concentrate and Mineral Tailings. Keywords: tailings disposal, dewatering, drying, mineral tailings

Sep 1, 2012

By S. Sarioglan

The bleaching of edible oils, industrial oils, and some chemicals may be achieved using natural and acid-activated clays. These materials remove impurities and pigments from the oils. In this work, a bentonite clay from Turkey (Somas bentonite) was activated with different concentration of H2SO4 and HCl at 70~90°C and 5~8 hours. Under these conditions several cations were removed from natural bentonite (Al, Mg, and Fe) and DTA-TGA, FT-IR curves of the solids obtained after acid treatment were examined. Treatment time and acid concentration increased the degree of destruction of the bentonite structure which was determined by ICP. Activated samples were tested in order to verify their capacity to bleach soybean oil and compared to standard commercial bleaching clays. The experimental results indicate that treated samples with H2SO4 have the same efficient in bleaching crude soybean oil with the standards and treated sample with HCl is more efficient in bleaching than the commercial products.

Jan 1, 2014

There is a strong demand for nickel metal due to quick development of stainless steel and new electrical materials, most of which is extracted from sulfide resources, resulting in a serious depletion of sulfide resources. Therefore, more attentions have been paying to extracting nickel from nickel laterite, which accounts for some 50% of total nickel metal production. In this paper prereducing?magnetic separation?reduction smelting process is developed to manufacture ferronickel rom two types of nickel laterite DN and GN, assaying 1.42% 1.83% Ni and 49.09% 26.08%Fetotal, respectively. Mineralogy of two types of nickel laterite was determined and optimization of process parameters was conducted to manufacture ferronickel. Prereduction?magnetic concentration process is used to upgrade low grade nickel laterite firstly, two kinds of Ni-Fe concentrates being prepared of DN assaying 2.26% Ni and 69.45% Fetotal and GN containing 2.76% Ni and 38.00% Fetotal. Finally, two types of ferronickel were produced by reduction smelting of prereduced concentrates DN and GN, DN and GN ferronickel contains 2.97% Ni and 6.58%Ni, 89.25%Fetotal and 89.95%Fetotal, respectively. The total recoveries of Ni and Fe of the two ferronickel are beyond 90% and 80%, respectively. There is significant difference in grade of magnetic concentrates and ferronickel between DN and GN laterite due to their different mineralogy, the former belongs to limonitic laterite and the latter saponite one. There are some advantages for this process to manufacture ferronickel from nickel laterite, including effectively upgrading low grade nickel laterite by prereducing?magnetic separation technique, higher throughput and lower energy available for reduction smelting section due to some 40% gangue being rejected in pre-upgrading section, and much less metallurgical coke consumption by using non-coking coal as reductant for prereducing?magnetic separation?smelting process.

Jan 1, 2014

By Xiaolu Ye

"Comprehensive utilization of Bi and Sn from the tin-associated polymetallic tailings by “gravity separation – flotation combination process” has been studied, which was verified that the novel process is an effective method to deal with the high content pyrrhotite tin-associated polymetallic tailings. In this investigation, ore property analysis and magnetism analysis of pyrrhotite were conducted to research and develop reasonable beneficiation flowsheet. The results of ore property analysis present that pyrrhotite was not closely related to bismuth and tin minerals. Particle size analysis results indicated that pyrrhotite was mainly in the form of fine particles. The magnetic analysis results show that pyrrhotite was distribution in all the three types of pyrrhotite in a single mining area, which indicated that variable magnetism of with different crystal structure pyrrhotite. The process of “low intensity magnetic separation - high intensity magnetic separation” shown an excellent adaption for the high content pyrrhotite tin-associated polymetallic ore compared with the single flotation process based on the magnetism variable of pyrrhotite. The results of whole process test indicated that a bismuth coarse concentrate assaying 5.63% of Bi at 81.77% recovery was obtained, which treat the conditions for the Bi-S separation flotation. In addition, the content of sulfur in the tin concentrate decreased from 2.5% to 1.5%, which provided a new reference for other tin-associated polymetallic tailings. INTRODUCTION Tin has been applied extensively in catalytic chemistry, gas sensors, tin plating, and plumbing. Tin-bearing polymetallic ores have been the important deposit types to recycle tin with the rapid depletion of mineral resources. The comprehensive utilization of the associated elements has been a preoccupation for the mineral processing researchers."

Jan 1, 2018

By Paulo Braga, Carlos Junior, Silvia França

"Lithium is the lightest of the metals, with high reactivity and great electrochemical potential. It has a low thermal expansion coefficient and high caloric value, and it forms very light and resistant aluminium alloys. These properties make lithium an attractive element for use in battery manufacture and glass and ceramics production, in addition to its applications in the aeronautic industry. Today, two sources of raw material are economically viable for lithium production: pegmatite rocks and brine. The world production, in 2012, was approximately 150,000 tons of LCE (lithium carbonate equivalent), almost triple the production in 2000. The forecasted consumption for the current year, 2013, was approximately 162,000 tons of LCE, and for 2020, it could be as much as 280,000 tons of LCE, stimulated essentially by the growth of world production of electric (EV), hybrid (HEV) and hybrid plug-in vehicles (PHEV), the batteries of which are based on Li-ions. With the growth of world demand and increasing prices, lithium minerals such as spodumene, petalite and amblygonite, once considered uneconomical for the production of lithium carbonate, are regaining their economic value. New projects to produce lithium compounds based on mineral sources are being developed in many countries, aiming to produce battery-grade lithium carbonate (99.95% Li2CO3). Although Brazil has large lithium pegmatite reserves, the domestic production of lithium carbonate and hydroxide is very low, at approximately 600 tons of LCE, which represents 0.4% of the world production. The application of these products is mostly in the grease and ceramic industries. The national lithium market is under government protection due to its potential use for nuclear purposes. Thus, the industrialization activities and import and export of ores and lithium minerals, as well as organic and inorganic products, such as metallic lithium and lithium alloys, are controlled by the National Commission for Nuclear Energy (Comissão Nacional de Energia Nuclear - CNEN). The objectives of this work to quantify the real lithium demand in the Brazilian market, considering that a large amount of lithium is indirectly imported in the form of the Li-ion batteries used in equipment such as mobile phones, cameras, tablets, notebooks and e-bikes, and to compare this demand with the current national production of LCE. Finally, some technological alternatives will be discussed, with the aim of increasing the competitiveness of the lithium industry in Brazil."

Jan 1, 2014

By S. Banisi

Thickening is the most widely applied dewatering technique in mineral processing. Thickeners are used to increase the concentration of suspension by sedimentation, accompanied by the formation of a clear liquid. As the particles get finer the thickening process encounters difficulty due to a significant change in the settling behaviour of particles. The batch settling tests of coal refuse of a coal washing plant which contained 91% particles smaller than 38µm and 0.6% coarser than 75 µm showed that the optimum feed percent solids that provided highest flux (solids handling capacity) was 4%. The flux of the pulp with the plant solids concentration (i.e., 10%) was 60% lower than that of the pulp with 4% solids. A thickener with a diameter of 22m based on the dilution of feed from solids concentration of 10% to 4% was designed. Monitoring of the thickener performance for a period of one month in the plant indicated that on average the feedrate of 25t/h (dry solids) with solids concentration of 10% could be thickened to the underflow concentration of 26.5% with a clear water overflow. It was found that the key component of the successful operation of the thickener is the dilution of the feed without which the overflow loses its clarity and the system ceases to operate under predetermined conditions. Specially designed feeding system which efficiently dissipated the energy of the incoming flow and staged flocculant addition regime are among the main contributing factors in making the design and operation of such thickener possible.

Jan 1, 2014

By L. W. Luo

Zeolite in some regions or countries of the world have been the subjects of materials for environmental remediation involving the use of removal to heavy metal ions and some organic pollutant as a sorbent because of its capacious ions exchange and huge surface area. This article addresses the equilibrium and kinetics for manganese adsorption using zeolite modified by hexadecyl trimethyl ammonium bromide (HTMAB) as a sorbent material over a range of pH between 3.4~7.2 with eight different Mn(?) solution concentrations. PHzpc (pH of zero point charge) of the sorbent was examined according to the method proposed by Tripathy and Kanungo, and a value of 6.91 was obtained. The experimental data fit langmuir?s model for the majority of pH and Mn(?) solution concentrations tested (0.92<R2<0.97). The maximal adsorption capacity, qm ascending with pH between 3.4~7.2, rise from 15.01mg?g-1 at 3.4 to 19.46 mg?g-1 at 7.2. Besides, the constant of Freundlich Kf have the same trend with qm, increases with pH ascending. And the sorption intensity, represented by parameter 1/n in Freundlich?s model, is favorable in entire range of metal ions concentration studied. Finally, kinetics data accurately fit to pseudo-second order which indicate that there must be sorption of Mn(?) behavior occurring on inner-sphere of the sorbent.

Jan 1, 2014

By F. Q. Dong

According to the principle that should be originated from nature, compatible with nature, used in nature and back to nature and based on conception of designing of eco-material, the author combined the ideas of material, environment, zoology and healthy. Properties of natural mineral materials were used to produce micro-aggregate elements by bionic method, so its components and function could accord with living environment. Eco-mineral functional materials which can adjust, purify and optimize the microclimate were reviewed. The authors pointed out the multifunction, com-pounding, the compound characteristics and integration regularities of micro-aggregates. It was the first time in the world to put forward the ?gene? technique or ?material chip? technique of manufacturing function micro-aggregates and eco-function elementary materials. The results of this re-search supported by the national ?863? Hi-tech Project, mainly including the high-efficient air purifying mineral compound material indoor, the clay elementary antibacterial materials, the masonry cement/coating/putty/compound with preventing radon radiation, environmental friendly composite functional coatings, mosquito repellent and healthcare material and zeolite-based energy-saving composite materials, were introduced. Finally, the foreground of mineral materials in the field of future advanced eco-friendly materials was also discussed.

Jan 1, 2014

By J. Y. P. Leite

In the Borborema Pegmatitic Province (Brazil) exploitations of several minerals are conducted by small producers. They use traditional techniques of gravity concentration in small-scale plants as jigs and vibratory tables. During decades the mining activity generated tailings with economic interest in particularly columbite-tantalite. Samples collected in tailing piles of a gravity plant were characterized in mineral composition, which shows in the heavy fraction the minerals spodumene, columbite-tantalite, ilmeno-hematite, garnet and cassiterite. The light fraction presents quartz, feldspar and muscovite. The degree of liberation of spodumene and columbite-tantalite were determined using optical microscopy that presents liberation in 100 µm (90% to columbite-tantalite and 100% to spodumene). Centrifugal concentrator Falcon SB-40 was used for concentration of these minerals and presents 65% recovery in mass to two stages with mass reduction about 85%.

Sep 1, 2012

The addition of copper sulfate to mineral slurries in order to ?activate? sulfide mineral surfaces for enhanced collector molecule adsorption, and hence enhanced recovery via flotation, is a com-mon mineral processing practice. It has been established in a laboratory situation that the addition of CuSO4 in conjunction with xanthate collector increases the flotation rate of pentlandite as compared to the addition of collector alone. However, it remains unclear whether the addition of CuSO4has a similar effect within mineral processing circuits. We examine here the effect of pre-activation oxidation on the copper activation of pentlandite and monoclinic and hexagonal pyrrhotite. All activation experiments were carried out at pH 9 using a total solution content of copper ions equivalent to one monolayer (0.210 -4 moles, 110-4M). Copper loss from solution was extremely rapid in all cases with less than 10 % remaining after 10s. EDTA extraction and solution analysis clearly demonstrated that copper activation was via direct surface adsorption and not an ion exchange process, as is the case for sphalerite, and that most copper on the surfaces is in the form of Cu(I). ToF-SIMS analyses of the mineral surfaces subsequent to copper activation show increased surface oxidation on increased conditioning time prior to copper activation. However, there is a significant decrease in surface oxidation on comparison of samples that have otherwise been prepared in the same manner but where one has been exposed to copper solution rather than water. This suggests that copper activation stabilises the surface and reduces the propensity for oxidation. Regardless of the length of pre-activation oxidation time only Fe(III) (no Fe(II)-S) was observed by XPS analysis, indicating a highly oxidised surface layer dominated by Fe-O-OH species. The presence of Cu(II) on the mineral surface is indicative of the formation of Cu(II)-containing precipitates and indicates non-mineral specific activation resulting in increased recovery but lower grade. Mineral specific copper adsorption, as evidenced by the presence of Cu(I), is required to improve both grade and recovery. Prolonged oxidation prior to copper activation causes a reduction in the Cu(I) to Cu(II) ratio on the mineral surfaces as compared to either fresh surfaces or surfaces oxidised for 1 minute only. This strongly indicates that the copper activation process is less effective on highly oxidised surfaces.

Jan 1, 2014

By Chenyang Zhang, Zhigang Yin, Jianyong He, Yuehua Hu

"A lot of floatation reagents (collectors, inhibitors and regulators) for the beneficiation of copper ores have been well developed in the past century. However, it is still unclear about the micro interaction mechanism of these flotation reagents with copper ores. In this paper, the interaction mechanism of these flotation reagents with the copper atom on chalcopyrite has been systematically investigated by first principle DFT (density functional theory) calculations. Thirty-four specific common functional groups linked with the same hydrocarbon chain (ethyl) are optimized at a B3LYP/def2-TZVP level, the solvation effect was included with the SMD solvation model. The analysis of the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and nature bond orbital (NBO) charge of these reagents reveals their potential applications to other types of copper-bearing mineral. Further investigation of the thermodynamics calculations gives more reliable data to screen collectors or inhibitors for copper-bearing mineral. The flotation results from carefully reviewed literatures are in good agreement with the calculation results. This work might also shed new light on the development and discovery of highly efficient and selective flotation reagents with low cost based on the computational methods.INTRODUCTION Froth flotation,(Shean & Cilliers, 2011) a mineral processing approach, is applied to efficiently enrich valuable minerals from the mixture, which is achieved according to the dictinctive surface properties of minerals. In the past century, researchers have develped an aboundant of flotation reagents by extraction or synthetize, and many carefully selected reagents might die in the bench tests or the pilot tests before the pratice.(Bulatovic & SrdjanM, 2007) Generally, it involves a lot of cost and tedious works by conducting flotation tests to screen flotation reagents. Flotation reagents have been boomed robustly with the developing of the organic synthesis.(Liu, Yang, & Zhong, 2017) Reseachers found the specific properties of a reagent are determined by its functional groups and the length of the hydrocarbon, where the functional group is assigned as the adsorption site to adsorb onto mineral surfaces and the hydrocarbon chain is called as a hydrophobic group."

Jan 1, 2018

By X. Y. Liu

A culture-independent approach based on 16S rRNA gene clone library was used to analyze the bacterial community change both associated to the solids and in the liquid phase during pyrite bioleaching process. Phylogenetic analyses of 16S rRNA fragments revealed that the retrieved se-quences mainly related to genus Leptospirillum, genus Sulfobacillus and genus Acidithiobacillus. During the bioleaching process, genus Leptospirillum trends to grow associated to the solids while major of genus Sulfobacillus were in the liquid fase, only accounting little portion in the solids. Genus Acidithiobacillus can grow both on the solids and in the liquid phase, but accounting high portion on the solids.

Jan 1, 2014

By V. A. Chanturiya

The results of development of new collecting reagents selectively interacting with the metals of platinum group (MPG) are presented. A new approach to the concentration of the platinum minerals from the fine grade platinum containing products with the use of cloud point polymers for the first time proposed for this purpose is discussed. An original method for the investigation of complexing reagents with the platinum under flotation conditions developed by authors is described. The influence of the complexing reagents on the xanthate adsorption and on the electrochemical properties of the platinum arsenide surface (sperrylite) as well with the interaction mechanism between the reagent and metallic platinum were investigated by means of the modern physical and physicochemical methods of the solid and fluid phase studies. The results of tests of some complexing reagents with the rich copper-nickel ore in the cycle of nickel-pyrrhotite flotation are given. The data obtained makes it possible to mark the complexing reagent containing phosphine group as the most effective additional collector for MPG. Cloud point polymers containing thioamide, aminosulphide, and phosphine functional groups were examined. It is shown that all the reagents tested increase the platinum and palladium extraction to the nickel-pyrrhotite concentrate without quality loss. Platinum containing particles flocculate selectively.

Jan 1, 2014

By Evvie Chockalingam

Acid mine drainage (AMD) is a perennial problem particularly in abandoned mines, occurring due to the oxidation of sulphidic mine wastes. AMD is usually characterized by high concentration of dissolved metal ions, sulphate and low pH. The efficacies of substrates such as rice husk and the bark of Eucalyptus tereticornis (Sm.) are assessed for the removal of metal ions such as iron, zinc and copper from acid mine water obtained from an abandoned copper mine. Over 99 % of Fe, 98 % of Zn and 95 % of Cu removal could be achieved from acid mine water, with a concomitant increase in the pH value by three units using rice husk as an adsorbent. With respect to tree bark as an adsor-bent, about 96 % of Fe, 75 % of Zn and 92 % of Cu could be removed from the acid mine water with an attendant increase in the pH value by two units. The free energy of adsorption of the metal ions onto rice husk and tree bark is found to be negative in both the cases, while the adsorption process is endothermic in the case of rice husk and exothermic for tree bark. The adsorption process is found to adhere to the Lagergren pseudo-first order rate equation. The reduction of sulphate con-centration in the acid mine water is achieved using a typical sulphate reducing bacteria namely De-sulfotomaculum nigrificans. Desorption experiments indicate that about 88 % of Zn, 87% of Cu and over 77 % of Fe could be recovered from rice husk and over 70 % of Fe, 82 % of Zn and 77 % of Cu could be desorbed from the metal loaded tree bark using 5 M HCl. The possible mechanisms of metal ion and sulphate removal from acid mine water using rice husk and tree bark are discussed.

Jan 1, 2014

By M. Saghaeian, R. Hejazi, R. Barreiro, M. Tavousi, M. Ahadi, O. Asghari

"Banded iron formations are the major iron source for producing high grade concentrate. BIF are generally lower grade and more difficult to extract. In order to know how best to process BIF ore, it require comprehensive knowledge on ore bodies even in the early stages of the mining process. Geometallurgy combines geological and mineral processing information and allows for higher flexibility in response to changes in the plant feed when mining different parts of the ore. This can lead to economic benefits, owing to improved plant operation, yet is time consuming and correspondingly costly. The main focus of this paper work has been to develop a comprehensive geometallurgical testing framework for developing Yogi BIF low grade magnetite deposit located at Western Australia. In order to provide successful geometallurgical mapping, was collected data from several different disciplines (geology, chemistry, mineralogy) and parameters (physical properties, metallurgical response and geotechnical measurements) during drilling activities and test work. The investigation shown magnetic separation behavior of material had high variation and is most important element in the proper design of ore beneficiation plant. This paper provides an improved and efficient magnetic separation test methods used for the investigation of separation behavior and variability of the Yogi Ore deposit and evaluates their applicability and potential in the geometallurgical context. In this paper a small-scale magnetic separation has been developed that allows estimating from single pass separation test using small amounts of sample material. Verification of the evaluation method and validation was done with different mineral systems."

Jan 1, 2018

By Georges Delemontex, Nigel Grigg

"Pre-concentration of precious metal and base metal ore types is becoming more relevant with the discovery, development and operation of many lower grade deposits around the world. The fluctuations in metal prices and currencies expose many mines to risks especially dealing with low and variable ore grades. Pre-concentration, the process of concentrating the valuable metal into a smaller mass yield, effectively results in the introduction of higher feed grades to milling circuits. Gangue rejection, the removal of lower S.G. waste rock from the circuit, not only results in higher downstream grades but also potentially removes harder, non-valuable mineral, providing significant power savings within the circuit. The pre-concentration or ‘gangue rejection’ process offers a number of benefits when considering the treatment of marginal ore deposits, especially if it can be performed at a coarse crush size; these benefits include a reduction of the operating costs and the feed of more metal units to the mill. Gekko Systems has effectively utilized the Inline Pressure Jig (IPJ) to pre-concentrate the valuable metal, achieving high primary recoveries into a range of mass yields resulting in upgrade ratios between 2 and 10 times. This paper explores: the benefits of pre-concentrating ‘marginal’ ore deposits prior to the milling circuit; the selective rejection of ore types that may affect either the recovery or comminution process; and also looks into the potential to effectively reduce the ‘cut-off’ grade when considering the mine planning process. Case studies of projects using the IPJ to pre-concentrate and reject gangue are also included. Pre-concentration and gangue rejection provide the potential to develop marginal ore deposits, thus providing higher grades, less gangue and more metal at a lower operating cost to producers."

Jan 1, 2014

By X. H. Li, F. Xie, Q. Zhang, Z. H. Shen, S. Mao

"There is abundant rare-earth element(REE) in our country, but it is very fragmented in the earth's crust, and it is very difficult to mining or mining cost is extremely high. There are few of industrial value rare-earth deposits. There is a lot of concomitant rare-earth deposits, and the comprehensive utilization value is high. There is very rich carlin-type gold resource, associated with a certain amount of REE in the southwest of Guizhou province. In order toutilize comprehensively the resources, this paper conducts the study on the occurrence characteristics of REE in the ore. By the chemical analysis, the gold grade is 3.35g/t, the organic carbon 0.81%, the total REE 0.022%, which is a high carbon fine disseminated gold ore. By the optical microscope and XRD analysis, the major minerals are quartz, pyrite, calcite, limonite, arsenopyrite, mica, kaolinite, clay minerals, etc. In addition, there is a large amount of carbonaceous materials, such as organic carbon, graphite, which is harmful on leaching of gold. By the scanning electron microscopy analysis, there are thorium, lanthanum and neodymium, ytterbium, persimmon and other REE in the ore. Gravity separation shows that REE could be enriched to lighter material mainly, which indicates that REE disseminate closely with lighter materials.INTRODUCTION Carlin-type gold ore is important gold resource in the world, which are mainly distributed in Nevada and its vicinity, as well as the two Golden Triangle of Yunnan, Guizhou, Guangxi and Sichuan, Shanxi, Gansu province in China(Su W.C. et al.,2009; Xia G.X.,1996).Guizhou carlin-type gold ore is the second largest gold resource in the world(Muntean J L et al.,2011), distributing along the southwestern margin of the Yangtze plate, mainly mineralizing in the neopaleozoic-early mesozoic(Xie Z J et al.,2017). Many large gold deposits have been found in southwest in Guizhou in twentieth century, such as Zimuyou,Getang, Lannigou, Shuiyindong and Laowanchang gold deposit, and so on, and the gold reserves reach over 100 tons(Xia Y. et al.,2009).There is a certain amount of rare-earth resource in the carlin-type gold ore in the southwest in Guizhou province, and the current researches might mainly focus on characteristics of REE from the angle of geological mineralization(AnanyevY.,2015), not from the angle of separation and enrichment."

Jan 1, 2018

By E. Alldén Öberg

In 2004, LKAB decided to start a basic engineering study in expanding its existing production lines at the Malmberget mine site. It was expected that some of the production lines would become bottlenecks with reference to capacity. In this study, the sorting plant is examined and the results show that several unit operations will be limiting under current operating conditions. An additional purpose with the study was to investigate how replacement of some machines would influence performance and if production plans for the coming years might be achieved. Steady-state simulations using the software Modsim? were extensively used to study process performance for different operating conditions, such as iron content and size distribution in run-of-mine ore. Model parameters were derived from pilot plant data and when possible from ex-isting circuits. A complication for the simulations was the lack of relevant data and therefore some of the initial results were only indicative. The result shows that installation of new screens would give a much better operation, but also new crushers would be an improvement. This, since they can be run with full crusher chamber and tighter CSS. During 2007, most of the proposed remedies were implemented and the result is that the bottle-necks are gone, and the grades and material balances are even better than what was envisioned from the simulations.

Jan 1, 2014