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By D. C. R. Espinosa, P. Aliprandini, J. A. S. Tenório, M. M. Jiménez Correa

"Nickel and cobalt are the main value metals in nickel laterite ore. Cyanex 272 is an extractant used to separate nickel from cobalt present in leach solutions. Previous studies demonstrated the extraction of cobalt, magnesium and manganese at pH 5 using Cyanex 272 as extractant, while nickel remained in aqueous solution. However, it is difficult to separate cobalt from a solution containing magnesium and manganese. One possibility to change the metals’ behavior during the solvent extraction process is to change the mixture of extractants used. In order to study the solvent extraction of cobalt from a solution containing manganese, magnesium and nickel, a mixture of two extractants was investigated. Cyanex 272 (CY) and Versatic 10 (VC) were selected as extractants in the organic phase. The extractant concentrations used were: 20% CY; 15% CY, 5% VC; 10% CY, 10% VC; 5% CY, 15% VC; and 20% VC. In all cases, kerosene was used as a diluent, at 80 vol%. The synthetic leach solution used in this study was prepared according to the composition of a typical nickel laterite leach solution. The pH value of the solution used was 5, and the aqueous/organic ratio used in solvent extraction testwork was 1/1. The study has shown that the composition of the organic extractant mixture did not increase cobalt separation.INTRODUCTION Sulfide and laterite deposits are the main sources of nickel. However, production from nickel sulfide ores has been decreasing over the years, relatively speaking, increasing the focus on the exploitation of laterite nickel ores (McDonald & Whittington, 2008). Laterite ore deposits are found in tropical and subtropical regions. A characteristic of laterite ores is the presence of a complex and heterogeneous mixture of metals (Crundwell, Moats, Ramachandran, Robinson, & Davenport, 2011; Georgiou & Papangelakis, 1998; Gupta, 2003; Kesler & Simon, 2015; Moskalyk & Alfantazi, 2002; Oliveira, 1990). Nickel concentrations in laterite ores are typically 1–2% (Dalvi, Bacon, & Osborne, 2004)."

Jan 1, 2017

By D. M. Muir

Many plants produce iron(II)/(III) waste liquors which must be treated by neutralisation and precipitation to remove the iron. Iron can be precipitated as crystalline goethite or jarosite by controlled oxidation at low pH and as magnetite by controlled oxidation at high pH, but only at elevated temperatures (>70°C). This study focuses on the characterisation and settling properties of the iron oxides produced at ambient temperatures using various neutralising agents in order to improve the performance of thickeners. It was found that two-stage addition of caustic to FeC12 solutions produced a fast settling material characterised by Mossbauer spectroscopy and XRD as maghemite and magnetite. However, lime and magnesia additions resulted in more ferrihydrite formation and much lower settling rates because of the enhanced oxidation of Fe(II) by air. Settling rates decreased significantly as the proportion of Fe(III) to Fe(II) in the liquor increased. The mechanism of iron oxide precipitation is discussed together with some reasons for the different behaviour of the neutralising agents.

Jan 1, 2006

By X. S. Fan, T. R. Feng, D. Chen

To meet the flotation process requirements, the large-scale flotation cell must be designed for sufficient pulp mixing, reasonable air dispersion and solid suspension, which is very difficult to design for super large-scale flotation cell. Hence, the flotation cell scale-up and optimization for a short period is a challenge for super large-scale flotation cell design. Computational fluid dynamics simulation has been applied in flotation cell study, which is effective, timesaving and low cost in the study of the flow field distribution for super large-scale flotation cell. This paper demonstrates the flow field characteristics in the 600m3 flotation cell by CFD. The flotation cell model is meshed with hexahedral grid and the high mesh quality assures the computational precision. MRF model, namely a steady-state approximation, ensures that individual cell zones can be assigned different rotational speed. Euler-Euler approach is chosen for multiphase flow simulation to treat different phases as interpenetrating continua. Numerical simulation of single phase, two-phase and three-phase are investigated respectively. Results suggested that the flotation cell has the apparent upper and lower flow circulation. In condition of the impeller rotation, the air is dispersed reasonably. In addition, the solid phase volume concentration distribution in the cell has a little difference.

Jan 1, 2015

By D. L. Morgan, J. A. Butterfield

"Geological data, production trends and current projects underway suggest that enough molybdenum will be available from more diversified sources to meet the world's growing demands. The growth in molybdenum consumption has been primarily related to its beneficial effects as an alloying agent in steel. This rapid growth has been deliberately fostered by stable prices, adequate supply and application research. The molybdenum industry is now in a process of change which has been seen in several other metals, such as aluminum and nickel. As supply sources have become more diversified, the market has become more competitive. The recent drop in consumption has led to excess production capacity, accumulation of substantial producer inventories and increased market uncertainties. While consumption is expected to increase in the next two to three years, it will take some time to absorb the excess capacity and inventory. The increased proportion of by-product capacity indicates that prices may become more variable. Producer discipline will be required to prevent serious price erosion in times of surplus. Future prices may not continue to increase with inflation. For the longer term, several factors favour the increased consumption of molybdenum. Engineering requirements are becoming more severe and molybdenum alloys can help to meet these changing needs. In addition, consumers can rely on a large and increasing supply of molybdenum. A 7 per cent growth rate in consumption can probably be sustained through the next decade, but new applications and reasonably stable prices will be needed to make this possible."

Jan 1, 1972

By R. Esteban, D. Runnels, S. Girgin, J. Torrealba-Vargas

"Each mineral processing project requires early testwork to evaluate the economic potential of a deposit. The testwork needs to be efficient and it should provide enough information to obtain key parameters, first for a high level flowsheet selection at the conceptual and PEA stages and then, for later stages, to confirm the flowsheet selection and optimize the metallurgical efficiency of the plant. The testwork should consider all rock types or lithologies present, and carry out testwork for the purpose of sizing the major processing equipment.A successful project requires that the project stakeholders develop an efficient sample collection program to produce enough material for a scoping and pre-feasibility level program. This involves the participation of a team of geologists, mining and metallurgical engineers in the project, as early as possible, to define the deposit characteristics that need to be validated.The project schedule requires a close control of the testwork scope, procedures, and timing, but also the efficient analysis of results to provide indications of red flags that could impact circuit design as early as possible.In some cases, projects are put on hold due to fluctuations of the world economy until the return of more favorable conditions. In that scenario, prior data analysis of former testwork results could reduce significantly the amount of testwork required to restart a project. The paper will also present examples where the analysis of former testwork data was used to reduce the amount of new testwork in addition to presenting examples of latest projects where the above-mentioned test program approach was followed."

Jan 1, 2016

By S. Klingmann

ABSTRACT In this paper, we used data collected from the Gibraltar mine to analyze the effect of the TyreSense tire monitoring system on tire performance by reducing tire wear and preventing premature tire failure or damage. We analyzed the relationship between tire temperature, tire pressure, and tire failure or damage to help better understand the importance of controlling high tire temperature and pressure. The results enhance and expand the knowledge of the management of tire operational pressure and temperature.

Jan 1, 2014

By R. E. Dye

Introduction Research concerning all phases of hoisting practice, but more particularly the causes and prevention of hoisting rope deterioration and the improvement of safety dogs 158 for shaft conveyances, has been carried on intensively for the past three years in the Province of Ontario. Prior to the hoisting accident at the Paymaster mine on February 2nd, 1945, there had been no fatalities in the Province due to a hoisting rope failure. It was probably on this account that little original research on hoisting problems had been undertaken here and that the mining industry had been content to look to British, South African, and United States investigators for new developments in this field. Except for the Paymaster accident this might still be the case since, in any industry, it is apparently necessary for a serious accident to occur before any extensive programme of preventive research is launched. When this accident occurred, the Government of Ontario, with the close co-operation of the Paymaster officials and the mining industry as a whole, took immediate steps to determine the cause. A five-man, non-industry committee, selected from the Faculty of the University of Toronto with Dean C. R. Young as Chairman, was appointed by the Government, and a three-man Committee consisting of R. D. Parker, General Superintendent of the International Nickel Company of Canada, Limited, R. L. Healy, General Manager of Wright Hargreaves Mines, Limited, and R. E. Dye, General Manager of Dome Mines, Limited, with the latter acting as Chairman, was appointed by the Ontario Mining Association.

Jan 1, 1948

By Peter Hood

Data on world-wide geophysical activity in mining exploration programs are collected annually by the Society of Exploration Geophysicists' Geo-physical Activity Committee as part of a continuing service to the industry. The data are obtained by sending out questionnaires to all organizations which are known to be carrying out mining geophysical work; the organizations canvassed include mining companies, contractors, government departments and universities. The questionnaire is divided into three sections; namely, ground methods, airborne methods and research. The data compiled from the questionnaires show that world-wide utilization of mining geophysical methods reached a new high in 1967 with total expenditures of (U .S.) $32,323,240. This was divided as follows: ground methods, $18,106,785; airborne methods, $10,-123,405; and research, $4,093,050. For the ground methods, most money was spent on the induced polarization technique ($5,681,780); electromagne-tic methods were second in reported expenditures ($2,010,900). The total reported geophysical line mileage flown was 1,275,072 line miles, with aeromagnetic surveying being the most popular airborne method. The total amount spent on aeromagnetic surveys was $5,832,564 for 895,420 line miles. This gives an average cost of (U.S.)$6.50 per line mile.

Jan 1, 1968

By K. Hardy

As part of Inco's $115 million Fluid Bed Roaster SO2 Abatement Project, a new weak acid treatment plant (WATP) was constructed to treat bleed solutions from the Copper Cliff Smelting Complex gas-cleaning circuits. The WATP produces an iron-arsenic co-precipitate, termed "basic ferric arsenate" (BFA), which requires disposal in an environmentally acceptable manner. Following analysis of many potential options, the short-listed disposal alternatives were: A) Co-disposal of the BFA?gypsum sludge with rock tailings, a portion of which would be used in mine backfill, with the remainder being sent to the tailings area, and B) Co-disposal of BFA?gypsum sludge with pyrrhotite tailings in the tailings area. Testwork showed that the addition of BFA?gypsum sludge to mine backfill samples increased the uniaxial compressive strength (UCS) of the backfill for most samples, especially those at lower binder content ratios. Extensive analysis was conducted on samples taken from the Copper Cliff tailings area, where BFA?gypsum sludge from Inco's Copper Refining Electrowinning Department has been co-deposited with pyrrhotite tailings since 1990. Pore water samples from these areas contained very low arsenic concentrations, indicating that the arsenic had remained stable in that environment. Ultimately, co-deposition with pyrrhotite tailings was chosen as the preferred option for the disposal of BFA?gypsum sludge from Inco's new WATP.

Jan 1, 2006

By J. R. Goode

ABSTRACT Aurora Energy Ltd. is considering a 10,000 t/d process plant to produce 97 million lb (43,998,460 kg) of U3O8 over a 17-year project from uranium deposits in coastal Labrador. This paper summarizes the test work, mostly done by SGS Mineral Services in Lakefield, Ontario, and the economic studies supporting flowsheet selection. The proposed flowsheet includes semi-autogenous grinding (SAG) and ball milling, acid leaching using air/SO2 as an oxidant, and resin-in-pulp (RIP) extraction of uranium from the leached slurry. Other unit operations examined include ore sorting, heap leaching, liquid- solid separation, solvent extraction, and nanofiltration for eluate upgrading. We also review the extensive environmental test work and studies that were completed.

Jan 1, 2012

By W. P. Campbell

THE investigation herein described had its beginning in the chemical laboratory of the Department of the Interior, Calgary. After the transfer of the natural resources to the Province of Alberta in 1930, the laboratory was closed and the investigation discontinued, but in 1933, with the permission of the Director of the Mines Branch, the work was again taken up and brought to completion. OBJECT OF THE INVESTIGATION The object of the investigation as originally planned may be stated as follows : (1) To determine the chemical composition of the limestone formation underlying Turner Valley gas field. (2) To identify 'beds' in the limestone, if such existed, with definitecharacteristics which would mark them from immediately overlying and underlying measures. (3) To relate information acquired on the composition of the limestone to the occurrence of oil and gas in the particular section examined. Definite information was lacking as to the exact chemical composition of the limestone and of its variations in composition at various depths. The formation was generally referred to in the field as the 'dolomitic' limestone, but the depth to which the dolomitized zone extended and the degree to which the limestone generally had become dolomitized were not known. Jn the drilling and logging of wells, the recognition of suitable 'markers' in the various formations is a matter of some importance. Markers are generally relatively small but widespread members of a formation, which have some characteristic property, of colour, composition, or form, by which they may be identified, and with them, consequently, the formation of which they form a part. In the formations above the limestone in Turner Valley, a number of well defined and easily recognized markers are known to geologists, drillers, and others interested in the field. Many of these markers Hand out in sharp contrast to adjoining measures and are therefore easily recognized; in others, the contrast is less sharp, with consequent difficulty in identification.

Jan 1, 1937

By L. E. Fischer

The background for the 630-million-dollar-plus iron ore project at Kudremukh is outlined. The system and plants for mining, crushing, concentrating, transporting via a slurry pipeline, filtering and shiploading 7.5 million metric tons of iron ore per year are fully described. The mode of operation and the problems encountered in such a transfer of North American technology to developing countries are analyzed. Difficulties encountered during construction are discussed and the progress milestones made over a two-year period are enumerated.

Jan 1, 1979

By T. Bhambhani, Mukund Vasudevan, Partha Patra, D. R. Nagaraj, P. Somasundaram

Selective Ni separation from ultramafic ores rich in serpentines has been a huge challenge in the mineral processing industry, and therefore highly inefficient. Analysis of the root causes of the challenges and consequent development of robust processing solutions were the main goals of the Cytec-Columbia. University-Vale Joint Development Program. In this context, the subject of this paper is limited to one of the key findings of this research program which is the influence of fibrous serpentines on grade-recovery characteristics. Specifically, the poor flotation behavior is characterized by an atypical reverse C-shaped grade-recovery curve.

Jan 1, 2011

By Erwin L. Zodrow

"IntroductionThrough an extensive coal sampling project in the Sydney coalfield of Nova Scotia during 1981 - 1984 involving a majority of the mineable coals (Zodrow, 1985, Fig. 1), a sizeable inventory on trace, minor and major metals was established. In this paper, results of studying the inventory are summarized, concentrating mainly on the relationship that exists between metal variations and thickness of coal channel samples (i.e. trends) and on explaining the trends in geochemical and sedimentological terms. As an over-all conclusion the Everglades peat of Florida is proposed as a modern-day analogue to Upper Carboniferous peat swamp development that took place in the Sydney Basin.Data InventoryFor this study 17 channel samples were cut , 8 cm to 14 cm channel width and 8 cm to 10 cm depth, from 10 successive coals which in stratigraphically descending order are as follows: Point Aconi (3), overrider Lloyd Cove (2), Lloyd Cove (2), Stubbart (2), Harbour (4), Backpit (I), Phalen (,I), Shoemaker (1) and McAulay (I), where bracketed values signify the number of channel samples cut from a seam (Zodrow, 1985, Fig. I). Each channel sample was subdivided by 15 em incremental length yielding a total sample size of 137 for analysis. By appropriate modern techniques these samples were analyzed to determine concentration levels for 32 chemical elements and ash content, the average results of which are presented in Table 1.Tests were also made for Pd, Pt, Ga, Nb, Cd, Cs, Sm and W but their concentration levels in many instances hovered on the lower detection limits that were used and on this accounts are excluded from discussion. Ashing, when necessary for the determination of concentration levels, was done for 12 hours at a temperature not exceeding 450°C. Concentration levels for the elements are reported in reference to whole-coal or whole-coal equivalents and discussed on this basis. In the course of the analyses, lower detection limits received careful attention."

Jan 1, 1986

By Donald Carlisle

"IntroductionTHE OPINION is held by many persons outside the mining industry, and by some within it, that mine •operators customarily find it advantageous to mine •only the richer parts of orebodies and to leave behind, perhaps permanently, leaner material which could be mined only at a lesser profit. This opinion and the inference which might be drawn from it that 'gutting' of mineral resources is a common feruture• of the mining industry are prejudicial to the intertsts of the industry and deserve careful scrutiny. Oddly enough, a theory of mine economics which gives much support for the opinion was advanced first by members of the mining profession itself, has been repeated •several times in mining literature, and to my knowledge has never been adequately refoted.According to the theory, selective mining of the rich ore first on a large scale will yield substantial gains and these gains do not merely reflect the desire of 'money minded investors' for a quick return but derive from the logical application of compound interest rates and the concept of ;present value. W. O. Hotchkiss and R. D. Parks (1) illustrate the reasoning with a hypothetical example in which an orebody of 4,000,000 tons may be mined either in its entirety in forty years at $1.00 per ton profit or selectively with the recovery of only the richest half in twenty years at $1.50 per ton profit. They show that, with Hoskold rates of 4 and 8 per cent, the present value of profits from mining only the richer 2,000,000 tons exceeds the present value of profits :from mining the whole orebody by about 20 per cent."

Jan 1, 1953

By P. M. Dranchuk

"""PLANET EARTH seen from space appears as a fragile and limited life-supporting system in a vast emptiness. That such a view is, in fact, an accurate one is now more widely accepted than it was not long ago, before Earth's problems of over-population, overconsumption, limited resources and environmental degradation attained the limelight. The danger is that a government and public now deluged by doomsday prophecies and bemused by equally confident reiterations that technology will cure all may hesitate in coming to grips with the problem, in the hope that, given time, it will go away."" With these words, Preston Cloud begins a recent editorial, in Science(l), in which he presents a brief resume of some of the findings of the Committee on Resources and Man of the National Academy of Science-National Research Council(20.Their report, which is based on a two-year study by an extremely competent group and consists of some 250 pages of text, is even more far-reaching and sobering than the report on Energy Resources(3). It begins by quoting Sir Macfarlane Burnet as follows:""There are three imperatives: to reduce war to a minimum; to stabilize human population, and to pre-vent the progressive destruction of the earth's irreplaceable resources.(4)"

Jan 1, 1971

By H P. Tardif

This paper briefly describes some of the phenomena encountered when materials are submitted to extremely high pressures, such as those produced by the detonation of an explosive charge placed in contact with the material. It was found that extensive changes take place in the? microstructure of iron and steel. Diffusion-controlled processes, such as the transformation of lamellar pearlite, the recrystallization and grain growth of ferrite, and the homogenization of the pearlite-ferrite structure, can take place within micro-or milliseconds. Mechanical twins can propagate without deviation from ferrite to pearlite, thus indicating a proeutectoid ferrite-pearlite-ferrite orientation relationship. The propagation and interaction of intense stress waves in materials was demonstrated with the use of Armco iron. Finally, a comparison is made of the damage produced in metals by the formation of craters made by explosive shock and by hypervelocity impact. D DRING the last few years, exceptional development has taken place in the field of explosive metallurgy, i.e., the

Jan 1, 1964

By Shiqiang (Rob) Hui, Jiaren (Jimmy) Jiang, Rees Llewellyn, Yongsong Xie

Wear has been estimated to cost the Canadian mining/mineral processing industry over $15 billion per year mainly for repair/replacement of worn parts in 2013. The associated production loss is difficult to quantify but add considerably to the problem. The Canadian oil sands sector which has to deal with extremely abrasive and erosive solids, has traditionally incurred extremely severe and often unique attack. Demonstrable progress in mitigating the wear problems has been achieved through materials development, more informed materials selections, and better component and operation condition designs. An integral contributor to these advances is a long-term collaborative research partnership between NRC and the mining/supply industry. In this paper, this continuing collaboration will be described. A main focus is to identify degradation mechanisms occurring in the most severe and important service applications and to correlate these findings with laboratory test data. Relevant abrasion and erosion (often combined with corrosion) properties have been established and correlated with composition and microstructures for all classes of resistant materials ranging from relatively soft elastomers to ultra-hard ceramics. A comprehensive wear properties database has been compiled. This capability has been instrumental in facilitating the development of improved materials, optimizing materials fitness/selection for service, wear failure analysis, and quality assurance.

Jan 1, 2015

By S. P. Lowe

Introduction In the following pages a general description is presented of the concentrator and cyanide plant of the Hudson Bay Mining and Smelting Company, Limited, at Flin Flon, Manitoba, together with some account of the steps which have led to the adoption of the present practice. For an account of the preliminary test-work and pilot-mill operation, the reader is referred to a recent paper by R. E. Phelan on the History of Flin Flon Mine up to Construction (1). Additional notes may be found in a paper which the writer presented at the Annual Meeting of the Institute in 1930 (2). The first ore was crushed in the present plant on July 1st, 1930, and the first ball-mill was started one month later, on August 1st. Since that time, production has been continuous with the exception of one month lost during a strike in the summer of 1934. There have been no major changes in equipment or methods of treatment since the present plant was built, but many minor changes have contributed to the improvement in results obtained and to the increase in capacity to the large tonnage now being milled. The accompanying flow-sheets indicate the equipment used in the several plants, with the average life and repair cost. As originally built, the concentrator was to treat 3,000 tons per day, but the capacity has been increased to 4,400 tons. The methods adopted to make possible this increase in tonnage will be referred to below. It was the intention to produce two classes of ore: (1) a heavy sulphide, and (2) a disseminated ore. The mill was consequently divided into two sections, each adapted for most efficient treatment of one particular type of ore. However, it was soon found that it would be impossible to mine the two classes of ore separately, so it was decided to treat open-pit ore, which varies greatly in character, in the sulphide section, and underground ore, which is fairly constant, in the disseminated section. This segregation is still maintained.

Jan 1, 1935

"Option pricing is used in finance for valuing options to buy (or sell) shares at some future date because it provides a convenient framework for quantifying values subject to uncertainty. As one of the main sources of uncertainty in mining is the price (sales) of the metal, this approach can also be used for valuing mining projects.The first part of this paper reviews options and option pricing; the second part presents the approach developed by Brennan and Schwartz (1985) for using option pricing to value natural resources. Several applications of this methodology have been published; these are described. From a mining point of view, the assumptions made by Brennan and Schwartz are too simplistic. The weaknesses are discussed with a view to improving an apparently promising new way of assessing the value of projects. IntroductionThe collapse of the British merchant banking group, Barings, has highlighted the risks that can be incurred by speculators and arbitragers in the futures and options markets. But this negative attention on futures and options should not make us forget their positive aspects. They can provide producers and consumers of metals with more predictable sales prices. The introduction of the new traded average price options, TAPOS, by the London Metal Exchange in January 1997 is a response to this need. Equally important, the theory that the finance industry has developed for valuing options provides an interesting framework for valuing mineral projects as well. While this paper was being revised, the South African gold mining house, JCI, announced that it was using a methodology based on option pricing for valuing the mineral rights to deeplevel gold resources (see Box 1)."

Jan 1, 1997