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By A. Miura, G. Granata, C. Tokoro, A. Fuwa

"The high copper demand as well as the lack of new high-grade deposits, are pushing the copper industry to process low-grade and refractory ores containing chalcopyrite. However, for a quantitative dissolution of copper from the chalcopyrite, the leaching performances still need to be improved. In the present research, we studied and optimized the iodide-assisted leaching of chalcopyrite in H2SO4-Fe2(SO4)3 media. The evolution of surface species during leaching was determined by x-ray photoelectron spectroscopy (XPS) and mineral liberation analysis (MLA). Inductively-coupled plasma spectrometry (ICP-MS) was used to determine the dissolved copper. Significance of experimental results was assessed by statistical analysis while a kinetic analysis of the leaching process was performed by fitting the experimental data with the Shrinking-core model. Results showed the significant positive effect of iodide on copper extraction rate. In the presence of KI, the dissolution rate of copper was almost double than in the parallel experiments without KI. Whether using KI or not, elemental sulfur was generated on the surface of the leached chalcopyrite. Nevertheless, in the presence of KI, the passivation layer did not arrest the leaching. Analysis revealed that the leaching rate was limited by the chemical reaction control step.INTRODUCTION Due to the large demand of copper, processing low-grade ores containing copper sulfides such as chalcopyrite (CuFeS2) has become unavoidable (Watling, 2013). Since ores with CuFeS2 may also contain appreciable amounts of arsenic that cannot be smelted, and because low-grade ores are uneconomic to smelt, the hydrometallurgical technologies are crucial for recovering the copper (Dutrizac, 1978). Sulfate-based processes are attractive because of the lower operating costs and because the sulfate ion is more suitable in case copper would be recovered via electrowinning. In ferric sulfate solution, chalcopyrite undergoes oxidation due to the large amount of Fe(III) and dissolution due to the presence of the sulfate ion (Majima, et al., 1985). The leaching reaction in ferric sulfate medium can be represented as in (1):"

Jan 1, 2017

By B. R. Richards, B. G. W. Robinson

"This paper shows how metal values can be profitably won from a comparatively small and remotely located but high-grade orebody. To do so is not uractical for a large mining company, with its necessarily high overhead of services and organization essential to a large producer.To evaluate, develop and profitably exploit a limited but defined ore deposit becomes only a problem of determining the dollars required to win the dollars available. This paper will record how this was carried out during 1965 and at the same time describe the history, development and production plant of this property."

Jan 1, 1966

By R. D. Merer

The production of low- and medium-Btu gas from coal provides a more economic source of energy for most industrial users than pipeline-quality coal gas (SNG), although the latter has received more publicity. The paper reviews existing and advanced methods of coal gasification, with particular emphasis on the production of low- and medium Btu gas for industrial and utility use. Some of the ways in which coal gasification can be integrated into power cycles and industrial plant energy balances are discussed.

Jan 1, 1978

By T. R. Stanley

Introduction The purpose of this paper is to interest mining men in the economic possibilities of sand deposits suitable for modern foundry work. Many members of the profession are constantly travelling over the country and it is felt that some knowledge of the necessary properties of foundry sands will enable these men t0 recognize such deposits. It is the experience of the writer that good sands suitable for the varied work of a foundry, such as that of the Consolidated Mining and Smelting Company, at Trail, are almost impossible to obtain from western Canadian sources. It is hoped that the following discussion may arouse some interest in the search for such sands. Sands are used in foundries for two purposes. The main use is for making moulds suitable for receiving hot metal. The mould must retain the? required shape until the metal has solidified. The second use of sand in the foundry is as an abrasive in sand blasting. This is a relatively minor use, and consequently will not be dealt with in detail. Any coarse sand with a high content of quartz will serve this purpose, but round-grained sands are superior to angular types, because they have not the same tendency to shatter on impact with the casting. Sand plays an extremely important part in the successful production of sound castings. This is more evident today than ever before, due to the greater variety of castings and alloys, each of which requires special sand characteristics. Poor sand is responsible for a great many foundry troubles which formerly were attributed to bad? metal; in fact, one investigator goes so far as to say that ninety per cent of bad castings can be traced directly to the sand. Very little of the vast amount of sand distributed over the earth's surface is suitable for moulding. It is the purpose of this paper to describe briefly the properties which are essential in good moulding sand. Sand for this work must be able to withstand the wash and hydrostatic pressure of molten metal, and yet be sufficiently porous to allow the gases generated in the mould to escape.

Jan 1, 1935

By D. D. Tannant, H. Ozturk

Thin spray-on liners are increasingly being used as rock support in underground mines. The adhesive strength between the liner and the rock surface is an important design parameter. Adhesion tests were conducted to assess the impact on adhesion of the presence of oil, water, and dust on a substrate, and the roughness and grain size of different substrates. Other factors such as curing time, loading rate, and liner thickness were also considered. Adhesion was measured using a pull test of a 33 mm diameter elevator bolt attached to an over-cored section of liner with strong epoxy. Most tests were performed using Tekflex liner material, although five other liner products were also tested. Adhesive strengths of about 2 MPa can be achieved with Tekflex under optimal conditions. Long-term creep tests showed that the adhesive strength could drop by at least 50% when the liner carries load for about a month. Where the rock surface is contaminated with dust or the rock is weak in tension, it may be difficult to reach adhesion strengths of 1 to 1.5 MPa. As the thickness of the liner increases, the adhesive strength to a substrate appears to decrease.

Jan 1, 2007

By M. Gagné, F. E. Goodwin

The mining industry represents a significant investment in infrastructure of which steel plays a key role. Many structures in a mine are made of steel including shaft structures (buntons, station steelwork and headgear); stope structures (roof supports, pipe hangers); haulageway structures (ore transfer stations, electrical stubbies); and surface structures (plant buildings, tank supports, pipe gantries, conveyor belts, stacks, stockpile structures, stairways and railings). Maintenance of structural components can often be difficult because of the environment, including those where corrosive fumes persist, or limited access, such as in shafts where access is limited, or to short maintenance shifts or where limited working space is available. Thus a cost-efficient, long-lasting and maintenance-free protection system for steel should be specified. Galvanizing provides the required high-quality, long-term corrosion protection to steel. Galvanizing provides protection in two ways, first as a physical barrier to corrosion and secondly by means of cathodic or sacrificial protection that is unique to zinc. The dual nature of corrosion protection provided by galvanizing significantly extends the service life of steel even in the most challenging environments. The unique corrosion protection properties provided by galvanized steel will be highlighted with global mining application case studies.

Jan 1, 2015

By Y. Feng

Perovskite structured oxide 15% Y-doped BaCeO3 (BCY15) has been evaluated for use as proton conducting electrolyte in SOFC with propane as the fuel and Pt as both electrodes. Under the fuel cell conditions, BCY15 exhibited high proton conductivity and good cell performances. Propylene was detected as product at the anode outlet, and the product distribution suggests that propane dehydrogenation underwent competition with cracking to lighter hydrocarbons. Stability during cell performance tests showed that there was no obvious degradation for BCY15 electrolyte during operation of C3H8-O2 fuel cell.

Jan 1, 2005

By John I. Sharpe

Masses of pyritic copper and zinc ores are entrapped along the contact zone between two volcanic groups in the Matagami area. The upper limits of the sulphide concentrations tend to form concordant contacts against lava or cherty tuffite units of the younger group; the lower extremities tend to either follow transverse structures or merge with zones of dispersed sulphides. The sulphides are deformed and intruded by folded dykes. Close relations between metallization boundaries and volcanic lithology and stratigraphy, and a preliminary investigation of the fabrics and crystallization temperatures of the sulphide masses, suggest that the copper and zinc (but; not necessarily all the iron sulphides) were emplaced at h1gh temperatures during volcanism in near-surface lithological-stratigraphic traps. Introduction T HE Matagami area is centered 120 miles north of the Val d'Or and Noranda camps in north-western Quebec. For the present purpose, it is considered to comprise a 155-square-mile area in Isle-Dieu, Galinee and Daniel townships which encompasses the main sulphide masses. Airborne geophysical surveys within this area in 1956 led to the discovery of a large sulphide body -the.

Jan 1, 1965

By Staff

The Tetreault mine, operated by the British Metal Corporation (Canada), Limited, holds a unique position in Canadian mining, being the only steady producer of zinc in Canada east of the Rocky mountains. Its importance in Canadian zinc production may be gauged with some accuracy, since, in 1927, it was responsible for over 13 per cent of the zinc output of the Dominion. In addition, it also made valuable contributions to the production of lead, silver, and gold. Location: Situated in the foothills of the Laurentian mountains, 600 feet above sea level, 20 miles from the St. Lawrence river, and 52 miles due west from the city of Quebec, the property is in the township of Montauban, county Portneuf, Province of Quebec, as shown in Figure I. The municipality of Montauban, immediately adjoining the mine, has a permanent population of 700 people and is six miles by road from Notre Dame station on the main line of the C.N. Rys. between Montreal and Chicoutimi-Notre Dame being n6 miles by rail from Montreal. Connection by 19 miles of dirt-and-gravel road with the Provincial highways' system of Quebec Province, the city of Quebec, which is distant 78 miles, can be reached by automobile in less than three hours, while the distance to Montreal by road is 16o miles .

Jan 1, 1928

By G. E. Rowan

"DURING the dark ages, the cherished dream of chemists was to find a process for converting base metal into gold. Many a wealthy-but-gullible patron lost a fortune in the search. Men who work with metals today are a bit more realistic. I haven't heard of a metallurgist who expects to develop any one alloy that will resist all corrosive media. In the field of stain-less steels, there are about forty different types of alloys that are used where corrosion is a •problem.A stainless product is ordinarily selected because it offers one or more of the following qualities:(1) Resistance to corrosion (2) Resistance to oxidation at high temperatures (3) Good mechanical properties at room temperature (4) Good mechanical properties at high or low temperature (5) Attractive appearance (6) Ease of maintenanceToday we are interested in discussing the stainless steel family of alloys because of their .ability to resist corrosion. We• will not try to explain the Theory of Corrosion. Let us assume that, when surface potential and oxide formations are properly controlled, iron will resist attack in various chemi.cal solutions. The addition of alloying elements to iron does this for stainless steels. The principal stainless alloys used by various Canadian industries are listed in the accompanying Table."

Jan 1, 1959

By Randy McMeekin, Chris Twigge-Molecey, J. Peter Blake

The project implementation phase, FEL4, is generally a complex undertaking. The project has been approved for construction and the capital has been allocated. At this point the project team comes under significant pressure to meet the safety, schedule, cost, and start-up committments. For the design team the principal tasks are to finalize detailed design, complete procurement, and issue construction contracts. Design activities must be closely coordinated with equipment and material procurement. A clear engineering plan should be based on well-defined work packages to meet construction, commissioning, and startup requirements. A range of review processes by discipline, area, and third parties assure quality. Constructability, safety, and hazard reviews are performed throughout the design process. Three-dimensional models that incorporate extensive databases help to maximize efficiency and minimize errors. Well-managed projects have a clearly accountable design team, rigorous change control processes, and well-defined workflows. Key individuals from the design team participate in commissioning, operator training, and startup.

Jan 1, 2015

By J. G. Debanne

MOST company-employed petroleum engineers have in their accounting departments punch-card computers that can perform engineering calculations thirty to three hundred times faster than desk calculators, or they can rent such machines from Computing Service centres. These machines not only eliminate the drudgery of desk calculation but also the risks of human errors. The I.B.M. t 604 punch-card computer of Texaco's accounting department in Calgary has been used for oil and gas property evaluations, curve fitting by least squares, statistical core analysis studies, unsteady-state water in-flux studies, phase equilibrium performance prediction of oil reservoirs, gravity segregation calculations, etc.

Jan 1, 1958

By C. A. Young, H-H. Huang, L. G. Twidwell

Equilibrium calculational software programs can be effectively utilized to model important parameters in aqueous and aqueous/solid systems, e.g., activity or concentration, solubility, temperature, solution pH, solution potential, and ligand complexation. In this regard, the calculational program ST ABCAL will be demonstrated. Illustrative examples for the creation of diagrams such as potential-pH, and activity or concentration-pH will be presented to demonstrate the fundamentals in real hydrometallurgical systems. Speciation, titration and mixing will be used to simulate or predict operational processes. Berkeley Pit water from a flooded abandoned copper open-pit mine will be used to illustrate the modeling process. According to analytical results the water contains about 20 important constituents. In addition to measured potential and dissolved oxygen, there are two distinctive oxidation/reduction couples. Concentration and other experimental parameters are seldom matched to each other and 12 different conditions have been identified. Water for each condition must be speciated in order to find the best-fit model. The STABCAL program will be used for the modeling calculations and the implication of the water chemistry to defining treatment opportunities will be discussed.

Jan 1, 2005

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened sorne time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too expensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By Hiwa Salimi, Foley. Stephen R, Loghman Moradi

Common water-miscible organic solvents including DMSO, DMF, methanol, ethanol, acetone and THF in combination with HCl and low concentrations of H2O2 were investigated for dissolution of gold. THF showed the best result demonstrating that gold powder could be completely dissolved in 1.5 hours in 1.0 mol/L HCl and 0.2 mol/L H2O2. No complete gold dissolution was observed for the rest of solvents even after 24 hours. The rate of gold dissolution was measured by dissolving gold wire in THF/HCl/H2O2 mixture. The rate of gold dissolution in optimised condition was 75 g m-2 h-1 at room temperature and significantly increased to 590 g m-2 h-1 by raising the temperature up to 60 oC. Although a THF/HCl/H2O2 mixture showed a slower dissolution rate in comparison with aqua regia, however the applied conditions are considerably milder which is highly promising for gold leaching in an industrial scale.

Jan 1, 2015

By Robert B. Parsons

"A t last the legal red tape which has tied up flow-through share financing has been cut. New rules effective for deals signed after 1986 simplify flow-through financing by removing the necessity f or cumbersome agency relationships. But there is no free lunch-the new rules require increased government reporting. And beware federal tax reform promises to have a good look at the new flow-through share rules. IntroductionFlow-through shares have always worked better in theory then reality as an effective financing tool. The concept is straightforward: a transfer of risks, tax deductions, and potential returns. But the mechanics of the old flow-through rules made the transfer of risk impractical to impossible by placing the responsibility for incurring Canadian exploration expense (CEE) on investors. The new rules are significantly more realistic, shifting that responsibility to the issuing corporation. However, every silver lining must have a few clouds around it. In the case of the new flow-through rules, the more obvious negatives are increased reporting requirements and reductions in CEE eligible for flow-through by amounts of assistance received. The new rules are effective for deals signed after 1986, however, so a few old-style deals are still around. Practical Difficulties with Old RulesThe old rules which applied to investments in flow-through shares were structured so as to make it the responsibility of the investor, rather than the issuing corporation, to perform the Canadian exploration expense for flow-through. Since most investors had neither the expertise nor the inclination to incur the CEE, this requirement necessitated the use of cumbersome arrangements whereby the investors would appoint an agent (usually the issuing corporation) to incur CEE on their behalf. Although the issuing corporation might consequently be the party which actually spends the flow-through share funds on CEE, the awkward legal structure of such an arrangement made the investor the ""principal"" incurring the CEE. As such, the requirements of the old rules were met and the investors could receive their flow-through share s."

Jan 1, 1987

By J. E. Udd, L. B. Geller

"Mine-shaft wire-rope discard regulations include, among other criteria, a limited amount of permissible loss-of-breaking-strength (LBS). Currently, this parameter is estimated on the basis of non-destrutive-testing (NDT) with electro-magnetic (EM) type instruments. This paper analyses the accuracy with which these estimates have, so far, been obtained in practice.It concludes that while certain types of testers have produced better results than others, the desired accuracy level has not been attained. Also discussed are the putative reasons for this situation, and appropriate actions that the mining industry might wish to take."

Jan 1, 1990

By Michael Magerstädt

Material loss by abrasion of contact surfaces of pipes, chutes, pumps, and other equipment in contact with ore is one of the main reasons for downtime of mining operations. Abrasion protection materials in use range from expensive tungsten carbide overlay to hardened steels, ceramics, as well as polymers, particularly polyurethanes (PUR). This paper describes abrasion protection products made from High Performance Polyurethane Elastomers. An interior pipe coating was developed that exhibited outstanding abrasion resistance and an extremely high adhesion to steel. Years of field testing in oil sands tailings as well as applications in slurry lines (e.g., phosphate slurries) have proven the performance of this material. A proprietary field joining process was developed and successfully applied in the field. This joining process requires only one field weld per joint very similar to the joining of uncoated pipe. No internal re-coating is necessary adding savings during pipe laying to the significant savings of reduced down time. Using the building-kit chemistry of polyurethane synthesis, similar high performance elastomers were used to extend the life time of ball mills. An intelligent system was developed in which wear parts contain sensors reporting the actual wear thereby optimizing maintenance interval leading to significant cost savings for the operator. Test data as well as field experience with High Performance PUR Elastomers for abrasion protection in mining are presented.

Aug 1, 2013

By The Mine Staff

THE PROPERTY of the Lamaque Mining Company, Limited, ?is located in the Town of Bourlamaque, seventy miles east of Noranda, in Bourlamaque township, Abitrbi county, north western Quebec. Gold production commenced at Lamaque in April, 1935, with an initial mill capacity of 250 tons per day. The capacity was doubled in November of the same year, and in December, 1937, it further increased to 1,200 tons per day. During the war years the mill operated at a reduced tonnage, but in 1951 milling units were added along with complementary crushing and shop facilities to bring the capacity to 1,500 tons per day. Finally, in 1953, the capacity was raised to 2,000 tons per day, which rate is being maintained at the present time. The total production at Lamaque from April 2nd, 1935, to December 31st, 1956, has been 9,168,901 tons of ore from which 2,208,168 ounces of gold was recovered. The total value of this production , excluding E.G. M.À.*, was $77,869,653.

Jan 1, 1957

By Roger M. Jones

This paper comments on developments in bulk shipping which will be of direct interest to those who are considering the shipment of dry bulk minerals out of Nova Scotia by water. Various conveying systems, and the slurry system of loading, are considered, and the role of deep water ports as a catalyst to other industries is stressed.

Jan 1, 1971