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By Art Hamilton

Abstract -The Zn-Pb-Cu-Ag ore deposits of the Boundary and N-5 zones near Bathurst, New Brunswick, occur in a polydeformed volcano-sedimentary sequence that is part of the Ordovician Tetagouche Group. Massive and disseminated sulfides are hosted by an argillaceous to cherty sedimentary sequence that is stratigraphically underlain by a siliceous fragmental unit and is overlain by a feldspar-rich crystal tuff and related tuffaceous rocks. The deposits have a low iron sulfide con­ tent relative to that of most stratabound sulfide deposits of the Bathurst-Newcastle mining district. The ore is commonly associated with chlorite- and talc-rich sediments. The N-5 deposit is considered to be the fault-displaced extension of the Boundary deposit. The Boundary deposit is estimated to contain 891 000 t grading 3.310Jo Pb, 7.96% Zn, 0.32% Cu and 44 g/t Ag; the estimate for the N-5 zone is 330 000 t grading 3.24% Pb, 7.15% Zn, 0.33% Cu, and 37 g/t Ag. The ore is processed at 1000 tpd at the Heath Steele mill.

Jan 1, 1992

By DONALD E. BARNETT

Since the days of early settlement ew Brunswick has produced a variety of industrial minerals but it is perhaps only the recent discoveries of significant reserves of potash that have elevated the meaning of industrial minerals in their contribution to the provincial economy. With potash production commencing in July 1983, the role of industrial minerals will increase significantly to the value of mineral production in the province.

Jan 1, 1984

By E. G. Bazeley

The paper reviews the scope, timing and financial impact of this significant project, which involves the supply and transportation of nearly 4 million tons per year of bituminous coal and lignite from sources in British Columbia. Alberta and Saskatchewan to Ontario Hydro's generating stations. The critical factors involved in the selection and utilization of these coals are discussed in relation to the three types of coal to be utilized initially. The paper then deals with each of the significant project elements to be undertaken by the various companies involved in the mining and movement of the coal, beginning with production at the mine through rail shipment to Thunder Bay, train-to-ship terminalling, shipment by lake vessel from there to the generating station, and finally blending the bituminous coal with United States coal prior to combustion. The review discusses the key features of the facilities involved in each case and the status and timing of the project elements , which are phased for the start of coal shipment by mid-1978. The paper concludes with some observations on the capability of the project to handle increased tonnage s and the challenges facing the movement in terms of quality , quantity and cost.

Jan 1, 1978

By Silvana Costa

The quality of life in remote mining communities is a significant factor that impacts the mining industry?s ability to attract and retain high quality workers in remote areas. The rapid growth of mining development, along with the shortage of skills and training globally are reflected in an increasing need to identify the ideal conditions for employee wellbeing and investigate ways to improve quality of life of miners and their families in remote locations.

May 1, 2007

By E. R. Hughes

Introduction Situated 182 miles east of Vancouver, on the Kettle Valley branch of the Canadian Pacific railway, the Princeton coal field is readily accessible to the Coast markets. The area covers approximately forty square miles and present indications are that the deposits should contain at least 300,000,000 tons of coal. Comparatively little development has yet taken place in this coal field. Since the commencement of recorded output, the collieries operating in this area have produced 1,640,518 tons of coal. The coal field proper includes only the Tertiary deposits adjacent to the town of Princeton and does not include the Coalmont or Nicola deposits. Production has never been on a large scale. The largest annual output from any property was 81, 780 long tons mined at the Granby colliery in 1940. Coal output was first recorded in 1909 and since that time fifteen properties are reported to have either mined coal or to have done prospecting or development work; of these, only two are presently active. However, none of the properties now inactive were closed because their coal resources were exhausted. The accompanying key map shows the extent of the Princeton coal field, and the location of the coal mines and prospects in this field General Geology The Princeton field is underlain by rocks of Oligocene age and is one of the series of more or less isolated Tertiary lake basins in which coal, or lignite, has been found in the interior of British Columbia. Resting on the Nicola group rocks of Triassic age, the Princeton sedimentaries consist of sandstones, conglomerates, shales, bentonite, bentonitic clays, and several seams of coal. Tertiary volcanics occur both above and below the stratified rocks and in places they have been thrust through the overlying measures. In some areas, the coal has been burned to a red ash as the result of vulcanism, while in other parts some of the moisture has been driven from the coal, thus improving the grade. The field can best be described by dividing it into two areas: the Southern area, lying to the south of the town of Princeton, where most of the mining has been done; and the Northern area, to the north of Princeton, where very little development has taken place.

Jan 1, 1947

By Richard W. Hutchinson, Robert W. Hodder

"Pyritic massive sulphide deposits lie conformably above submarine volcanic rocks, and beneath siliceous and manganiferous iron formations. The massive bodies are often zoned, with a barren pyritic top grading downward into pyrite with sphalerite, and occasionally galena, and a chalcopyrite-rich base. They are frequently brecciated, like the lavas beneath them, which contain pyrite and chalcopyrite as coatings on joints and fractures and as dispersed grains. The lavas also exhibit propylitic, argillic and silicic alteration. These sulphide deposits appear to have formed on sea bottom from fluids escaping through the lavas during periods of exhalative and sometimes explosive volcanism. The process may be comparable to the present deposition of base metals from hot brines in the Red Sea. Some porphyry copper deposits resemble the altered, sulphide-impregnated lavas which lie beneath bodies of pyritic massive sulphide. In porphyry copper deposits, pyrite and chalcopyrite occur as veinlets and dispersed grains in intensely fractured tuffs, flows, sub-volcanic intrusions or other host rocks, characterized by propylitic, argillic and silicic alteration. Metal zoning is present; sphalerite and galena often occur in manganiferous veins peripheral to a shell of pyritic veinlets which encloses the mineable zone of chalcopyrite-bearing veinlets. This sulphide distribution appears to have formed from hydrothermal fluids escaping, either passively or violently, from solidifying magma. The fluids may be comparable to hot brines encountered by drilling in the Salton Sea area of California.There are also important differences between massive sulphide and porphyry copper deposits. The former usually occur in differentiated, mafic-to-felsic subaqueous volcanic rocks, whereas porphyry copper deposits are often associated with shallow plutons and subaerial volcanic rocks of intermediate to felsic composition. Calcic-sodic metasomatism accompanies the massive sulphides, whereas potassic metasomatism characterizes the porphyry cop.per deposits. Further, ages of massive sulphides range from Archean (Keewatin) to Tertiary, but porphyry coppers are Triassic to Tertiary in age. These similarities and differences suggest that massive sulphide and porphyry copper deposits are related tectonically and metallogenetically. The former were generated during early stages of crustal evolution, particularly in Archean time, and were repeatedly derived during early stages of younger, individual tectonic cycles. In contrast, the porphyry coppers developed during the later stages of crustal evolution - later in terms of both absolute age and relative age within younger individual tectonic cycles. They appear in younger rocks generally, and specifically in rocks involved in events of the middle and late tectonic stages of orogenic belts. The massive sulphide deposits are of early-magmatic eugeosynclinal affiliation, whereas the porphyry deposits formed in late-magmatic, predominantly subvolcanic settings at the edge of continental plates, where contemporaneous exhalative volcanism was mainly a subaerial phenomenon. Transitional types of deposits exist and are found on continental margins with flanking eugeosynclinal sequences."

Jan 1, 1972

By C. J. Edmonds, R. Bland, W. C. Ferguson, R. Whitehead

"In 1969, the Environmental Science Division of James F. MacLaren Limited received authorization from The International Nickel Company of Canada, Limited to carry out a water quality monitoring program in the Lake Shebandowan region of Ontario, where a new base metal mining and milling complex was expected to go into operation in 1972. The objective of the program is to establish base-line water quality characteristics. Fully realizing their corporate responsibility to minimize the effects of the proposed activities on the environment, Inco decided that it would be desirable to establish a program by which any change in the quality of environmental waters will be detected before detrimental conditions ensue, permitting prompt corrective measures to be taken. The program has been in progress for over two years. The waters are sampled and analyzed four to six times per year. Sampling stations are located in Lake Shebandowan and on the adjacent Gold Creek - Matawin River system. On-site analyses and measurements are made of flow, dissolved oxygen, temperature and pH. Samples also are collected for later analysis in the laboratory. These samples are analyzed for a wide range of chemical and biological characteristics. The paper discusses the extent of the sampling program, the techniques utilized and the value of such programs in maintaining the quality of the environment."

Jan 1, 1973

By Karen Munro

Importance of Aquatic Studies for Mining ?Aquatic habitat is usually the first area where a mine interacts with the ?real world? outside the mine footprint ?Water management is a key consideration for a mine?Effects on the aquatic environment often extend to wildlife and human uses ?There is a lot of regulatory focus on issues of water quality, fish and fish habitat

May 1, 2011

By W. E. Uren

The Dominion Coal Board was created by Statute passed on July 17th, 1947, and was brought into effect by proclamation on October 21st, 1947. It is, consequently, a comparatively young body, having been in existence for only eighteen months. Before dealing with the constitution and duties of the Board, it may be well to answer the unspoken question of why it has been considered necessary to single out coal as one specific mineral requiring the continuous attention of a specially created permanent Board. In Canada, coal has been the neglected sister of the more spectacular minerals and it comes as a surprise co many to note that in 1948 the value of the coal produced in Canada was higher than that of any other mineral with the one exception of gold. Coal touches upon our daily lives in many different places of which the public are not generally conscious. As household fuel, it is a necessity of life in this northern climate; as a source of steam, it provides the heat for most of our industries; it is the food of the 'iron horse' chat shuttles our persons and our goods across the land; it is the source of power in many parts of the country; it is the chemical reducing agent chat, in our furnaces, transmutes the metallic oxides to the virgin metal. Coal is, in fact, the indispensable mineral chat forms the corner-stone of our present structure of industrial civilization. Is it, then, such an odd thing that the provision of an adequate supply of coal should be a matter of national interest or that measures should have been taken by government co provide for a constant watch, by a permanent Board, on the supply of co al? ? The Board is the result of the recommendations of the Royal Commission on coal which made a long and detailed study of the Canadian coal problem. It is composed of a permanent Chairman and six part-time members, most of whom have had intimate contact with various phases of the industry.

Jan 1, 1949

By William E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential.INTRODUCTIONThe purpose of this paper is to describe a cost approach to the valuation of mineral exploration properties and to provide some valuation examples. The particular cost approach described is the Appraised Value Method, which is best applied to mineral properties at the exploration stage.At present there are no comprehensive regulations or guidelines in Canada which specify what approaches and methods to use for the valuation of mineral properties. In this paper, the Appraised Value Method described is one method that the writer considers to be accepted industry practice for mineral properties at the exploration stage.Mineral properties are valued for a number of reasons, including mergers and acquisitions, non arm's length transactions, pricing of initial public offering of stock, support for property agreements, litigation, expropriation, and insurance claims."

Jan 1, 2003

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 Adrian Dance

Newmont Mining Corporation?s Carlin (?Carlin?) operation processes roaster feed through a double rotator, dry grinding mill following secondary crushing. Metso Process Technology & Innovation (?PTI?) was involved in a review of crushing and dry grinding circuit operations in August 2009. A number of opportunities for increased throughput were identified in the PTI study. Extended plant trials were conducted in July 2010 to provide justification for possible circuit modifications and if needed, additional equipment. The trials confirmed that a finer crusher product would reduce the build-up of material ahead of the coarse grinding chamber in the double-rotator. Also revealed were material transport and airflow restrictions in the dry grinding circuit that resulted in a high circulating load. The secondary crushing plant demonstrated it was capable of reducing the amount of +¾? material in the mill feed thus increasing dry grinding throughput. However, wet and sticky feed affected screening efficiency resulting in low utilisation of the existing crusher capacity. The open circuit configuration also made it difficult to control crushing circuit product size. For the dry grinding circuit, changes in grinding media size, transfer grate design and increased airflow were recommended to reduce circulating load issues and increase circuit capacity. This paper summarises the crushing and grinding circuit review, the extended site trials performed by PTI and the improvements in dry grinding operation that resulted from this study.

Jan 1, 2012

By R. Khanna, K. Hyun Ko, A. J. Berkovich, J. Hook

"The co-pyrolysis of synthetic polymer polyethylene terephthalate (PET) and agricultural wastes (naturally occurring polymer-macadamia nut shell) was investigated in the temperature range 473K to 1273K using a horizontal furnace with an aim to understand their thermal degradation under isothermal conditions. In-depth characterization of pyrolysis residues was carried out using x-ray diffraction (XRD) and solid state nuclear magnetic resonance (NMR) for carbon structure, and through determination of the concentration of unpaired electrons using electron paramagnetic resonance (EPR). In previous studies, it has been found that PET thermally decomposes ~ 650K-700K, releasing (~80 wt % of initial weight) gaseous products due to random chain scission. In the case of macadamia nut shell, three types of byproduct can be obtained from pyrolysis: char, tar and gaseous products. In the co-pyrolysis of macadamia nut shell with PET in 50-50 wt% ratio, total product weight ratio could be modified with the addition of PET acting as a hydrogen source. This is because a recombination of thermal cracking products of cellulose could be suppressed by hydrogen from PET, which will later lead to an enhancement of tar formation. In addition, pyrolysis around 673K is sufficient for bond cleavage to occur in cellulose and lignin leading to the formation of negatively charged activated carbon with high surface area, providing bonding sites for volatiles evolving from PET. Therefore the co-pyrolysis may be able to enhance the product yield (tar/char/solid carbon residue) along with a reduction in the release of gaseous products. During the co-pyrolysis, temperature was found to have a significant influence on the kinetics of thermal degradation and solid residual by-products after co-pyrolysis.INTRODUCTIONPlastics are being used worldwide in a wide range of applications in the modern society; their usage has resulted in increasingly a massive waste problem. The production of most synthetic plastics requires hydrocarbons that are produced from petrochemicals derived from fossil oil and natural gas, a non-renewable source (Speight 2011). Currently, plastic manufacture utilizes ~4% of world oil and gas production, and it is expected to drive further increases in petroleum demand by 1-2% due to their large volume of manufacture (Hopewell, Dvorak et al. 2009). Landfilling and incineration of plastic waste are the two main routes to plastic waste management (Encinar and González 2008). In Australia, only 10% of waste plastics were recycled in 2006 (White and Hyde 2011). This means that large amount of fossil fuels from plastics has either been simply burned for energy recovery or buried in the ground. There is an urgent need for developing alternative avenues for recycling waste plastics. Our group at UNSW has carried out extensive research on the recycling of waste polymers as carbon resource in steelmaking including slag foaming and carbon dissolution from waste plastics into liquid steel at 1600°C; the effect of basic plastic characteristics such as chemical composition, structure, bonding network etc. was examined (Sahajwalla, Rahman et al. 2009)"

Jan 1, 2012

By D. Duffy, V. Papangelakis

"MgCl2 brines present a number of potential advantages for the processing of saprolite ores for nickel production. With a chloride system it is economically requisite to recover hydrochloric acid, which can be performed in a more energy efficient manner by precipitation and subsequent decomposition, as compared with conventional pyrohydrolysis. In addition, concentrated MgCl2 solutions enhance the activity of acid used, allow atmospheric leaching at elevated temperature and inhibit magnesium dissolution, which reduces acid consumption and increases metal selectivity. Leaching and iron control experiments have been conducted in concentrated MgCl2 brines, up to 4.5 m, to determine the most amenable process conditions. INTRODUCTIONChloride metallurgy has received an increasing amount of attention in recent years, especially with respect to the treatment of nickel laterites. Although the limonitic fraction can sometimes be economically treated by High Pressure Acid Leaching (HPAL), acid-consumption problems are encountered with the higher magnesium content of the saprolite fraction. As magnesium does not hydrolyze under HPAL conditions, as iron and aluminum do, any sulphuric acid used to leach magnesium is subsequently neutralized and wasted. In addition, this magnesium must later be disposed of in some fashion, further complicating the process. The most common method used to process saprolite is the Rotary Kiln-Electric Furnace (RKEF). This uses a kiln to dry and preferentially reduce nickel, before sending the calcine to an electric furnace. Although nickel recoveries are high, and the problems of acid consumption are avoided, the capital and energy costs associated with this process are high (de Bakker, 2011).The problems outlined above have led to the investigation of an atmospheric chloride process for the treatment of saprolite ores. The use of a chloride system presents a number of advantages, but also a few limitations. Metal chlorides tend to be very soluble, with a few notable exceptions (silver, mercury and lead), allowing for smaller processing equipment through more concentrated solutions. This solubility also serves to reduce the potential for scale formation. In addition, a hydrochloric acid leach is more aggressive than a comparable sulphuric acid system, and the activity of the hydrogen ion can be augmented by further chloride addition (Peek, 2011). This activity augmentation in concentrated chloride systems, first reported by Jansz, has repeatedly been referenced as a motivating factor behind chloride hydrometallurgy (Jansz, 1983; Harris and Magee, 2003; Harris et al., 2004; Demopoulos et al., 2008; McDonald and Whittington, 2008; Demopoulos, 2011; Peek, 2011; Verhulst and Lakshmanan, 2011). This activity increase allows a similar amount of acid to perform more in a concentrated solution than in a dilute solution, decreasing overall acid requirements. As such, much focus has been placed on leaching in concentrated chloride systems, or brines, using calcium, magnesium or sodium as the cation (McDonald and Whittington, 2008)."

Jan 1, 2012

By Arthur Barnes, Mika Muinonen, M. J. Lavigne

"The carbothermic reduction of chromite ore to produce high carbon ferrochromium is among the most energy intensive metal extraction processes performed, due not only to the highly endothermic nature of the reduction reactions but also the very high operating temperatures required for the smelting operation to separate the chrome-containing alloy from the discard slag.KWG Resources and XPS have collaborated over the last 3 years in developing a patented (Winter) processing alternative to the traditional smelting operation in which all processing takes place in the solid state at temperatures many hundreds of degrees lower than those required for liquid processing. Amongst the attractions of the process are much lower capital costs, as well as reduced operating costs, particularly of energy.A techno-economic study on the new process identifies a reduction in overall energy consumption of 70% against conventional processing and approximately 40% lower than the current best practice. By utilising more natural gas than coal based energy sources, the KWG process is able to show an overall 50% reduction in greenhouse gas emissions compared with the most energy efficient current practice. The impact of the new process on future processing is therefore regarded as highly significant, with global energy reductions equivalent to the effect of completely eliminating energy demand from a country the size of Italy.The study concluded that the potential for this process to completely revolutionise the global ferrochrome industry should not be underestimated. Its impact reaches far beyond exploitation of a regional natural resource."

Jan 1, 2015

By Mike Fontaine

The success of a project is defined by meeting the financial performance objectives of the business case within a stipulated timeframe. Early in design, little information is normally available; the uncertainty introduces risk to the project outcome. Using a range of risk management tools and techniques, a project can be developed from front end loading phases 1 through 3 (FEL1–FEL3), and project implementation (FEL4) and then into operations with an optimized probability of success. For every project element, the risk management framework embodies: establishing a context; assessing risk (identify, analyze, and evaluate); and treating risk. Embedded within design activities, this process mitigates or eliminates risks. Monitoring and control, as well as extensive communication and consultation with stakeholders, is integral to the risk management process.

Jan 1, 2015

By K. Mayhew, R. Bruce, A. Heidel, G. P. Demopoulos

"Teck and Aurubis are working together to commercialize a technology for the processing of copper arsenic sulphide concentrates that is economic and sustainable with regards to the environment and community. The pressure hydrometallurgical approach is a desirable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. A test work program was carried out where a range of copper concentrates with varying arsenic grades was processed under CESL leach conditions. This paper discusses the stability character (in terms of arsenic) of the resulting residues and their mineralogy. The basic ferric arsenate sulphate phase (BFAS; otherwise known as type 2) was identified as the main arsenic carrier. All CESL residues demonstrated high stability (<1 mg/L As) through a range of aggressive (pH and ORP) environmental leach conditions.INTRODUCTIONArsenic deportment and control in the copper industry needs an integrated approach involving each stage of the value chain, i.e. exploration, mine operation, refining process and mine closure. Teck Resources Limited (Teck), Canada’s largest diversified mining company and Aurubis, Europe’s largest copper producer, have formed a partnership to advance the application of CESL copper-gold technology for the development of high arsenic bearing copper resources (Bruce et al., 2011).Among the options for arsenic control in the metallurgical treatment of copper concentrates is the precipitation of ferric arsenate, which is widely accepted as the most suitable method for stabilizing arsenic (Ferron and Wang, 2003). The pressure hydrometallurgical approach to processing arsenic bearing copper concentrates is a favorable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. Under CESL pressure leaching conditions (150 °C, 1380 kPa) high copper extraction and arsenic (V) fixation is possible.Within the pressure leach autoclave, arsenate and ferric iron react to form scorodite type phases. The precipitate formed under CESL conditions is dependent on the Fe (III) /As (V) ratio and the tenor of cations and anions, particularly excess sulphate (Gomez et al., 2011a). Previous studies on CESL residues have found arsenic to be present as crystalline scorodite (FeAsO4.2H2O) (Bruce et al., 2011), basic ferric arsenate sulphate (BFAS: Fe(AsO4)1-x(SO4)x(OH)x·(1-x)H2O, where 0.3<x<0.7), and/or arsenate adsorbed on to hematite (Gomez et al. 2011b). Although not a focus of previous work, scorodite was the predominant precipitate formed when the concentrate Fe/As was <1.5 (Mayhew et al., 2010), and BFAS was the predominant precipitate when the concentrate Fe/As was >10 (Gomez et al. 2011b)."

Jan 1, 2012

By C. Doyle, J. Brennan, C. Díaz, J. Hrepic, K. Cushnie

"In 1991/1992, INCO undertook a successful R&D program aimed at extending the lining lives of the top blown rotary converters (TBRCs)at its Copper Cliff Nickel Refinery (CCNR) and the electric furnace at INMETCO. At the laboratory scale, this effort was divided into three phases. In the first part, mineralogical work was performed on six refractories that were either currently being used to line these vessels or were considered suitable alternatives. In the second part, this mineralogical knowledge was used to help determine the compositions of slags that would not corrode the bricks at the operating temperature (1600°C) of the above furnaces. Finally, several important properties of the six refractories were measured to complete their evaluation as candidate linings. This paper reports the results of all three phases of the laboratory scale R&D work.The mineralogical work showed that rebonded fused grain magnesite-chrome (RFG-MC) bricks consist principally of periclase with minor amounts of free chromite and trace quantities of silicates monticellite and sometimes olivine. The bricks are principally held together by periclase-periclase direct bonding. Of note, the bulk of the chromite exists as exsolved precipitated blebs within the periclase grains. These likely redissolve at high temperature.Slags on the periclase liquidus coexist stably with these refractories. Examples are presented using CaO-MgO-Al2O3-SiO2 slags at~1600°C.Finally, the two refractories manufactured using close to 100% fused grain material generally outperformed the others in terms of physical properties and certainly were superior in their resistance to slag penetration damage."

Jan 1, 1997

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 A. G. Doll

The Bond low energy impact (crushing) work index test is specified to be performed on rock specimens between 50 mm and 75 mm in effective diameter. NQ-diameter drill core, frequently used in mineral exploration programs does not meet that specification, it being 45 mm diameter or less. This paper reports the effect of performing the impact test on contiguous sections of HQ diameter and NQ diameter core, exploring the hypothesis that the contiguous intervals give equivalent results in spite of the core diameter difference.

Jan 1, 2012