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By S. G. Shabestari, S. Saeidinia, P. Mokarian

"The experiments were conducted to investigate the influence of various process parameters in rotary degassing of aluminum alloy AS5U3G. Degassing was carried out by use of argon inert gas. The flow rate of the gas was investigated in the range of 12 to 21 L/min., 350 to 500 rpm rotor speed, 6 to 12 minutes degassing time, and 755°C to 780°C melt temperature. Degassing efficiency was evaluated through measuring the density of RPT samples. By optimizing the process parameters, RPT sample density was increased up to 2.73 g/cm3, which guaranties the production of high-quality aluminum castings. Tensile strength and elongation were increased considerably by degassing process. Scanning electron microscopy (SEM) shows small size and well-distributed microporosity. IntroductionOne of the major problems associated with the casting of aluminum alloys is the formation of gas porosity. Aluminum and its alloys are very susceptible to hydrogen absorption. Because solubility is much lower in solid state than liquid state, hydrogen atoms leave their position during solidification and combine together to form hydrogen molecules. These micrometer- scale cavities, called microporosity, cause the reduction of mechanical properties, particularly strength, ductility, fracture toughness, fatigue resistance, pressure tightness, and corrosion resistance (Laslaz, 1991; Jorstad and Rasmussen, 1993; Sigworth and Wang, 1994; Korasani, 1996; Anson and Gruzleski, 1999; Zhang et al., 2000). To avoid these problems and produce good quality castings, it is necessary to remove hydrogen from the melt. Several methods are available for degassing aluminum melt. One of them is a rotary degassing system using inert gas, e.g. Ar or N2. Various thermodynamic and kinetic factors govern the removal of hydrogen from molten aluminum (Anderson, 1987; Sigworth, 1987; Pignault, 1993; King and Reynolds, 1995). These are some parameters that affect degassing efficiency. Some of them are discussed here and some are examined in this project."

Jan 1, 2004

By J. E. Udd, L. P. Geldart, B. B. Dhar

"Solutions for the stress distributions around simulated underground openings have been limited to calculations of boundary stresses for simple openings in which the boundaries may be expressed in mathematical terms. Studies involving circles, ellipses and ovaloids are re-ported in the literature.The stresses on the boundary of an opening and those at a distance from it in the medium are of concern to the engineer. The former may be related to the greatest concentrations of stresses encountered; the latter have a bearing on the identification of the ""zone of influence"" of the opening.Recent advances, in the form of a derivation for the stresses at a distance from an opening of elliptical shape, together with a solution derived previously for stresses in depth around ovaloidal openings, have been combined with computer programming techniques to provide complete solutions for a wide range of cases and variables. Some typical results which, it is hoped, may have some application to the design of underground openings are given herein."

Jan 1, 1970

By Paul Billingsley

NICKEL Plate mountain coincides closely with that portion of the Hedley mining district which is of economic interest. From it has come almost the entire past production, and the active mines of the present epoch, Nickel Plate-Sunnyside and Hedley Mascot, lie in a compact group near its summit. The Hedley district, which is 210 miles due east of Vancouver, is situated in the Okanagan range of southern British Columbia, where this rather gentle uplift is deeply dissected by the canyons of the Similkameen and its tributaries. The region is essentially part of the Interior Plateau of the Province (Figure 1), but is adjacent to easterly elements of the Coast Range. The Similkameen canyon, 4,000 feet in depth and frequently less than 4 miles from rim to rim, traverses the district from northwest to southeast. The deepest and narrowest portion of the canyon lies between Hedley and Keremeos, 18 miles to the southeast. At Hedley, an important tributary, Twenty Mile creek, enters from the north in a bold canyon, making a focus of unusually rugged topography. Nickel Plate mountain occupies the sector to the east of this junction (see Figure 2) and its flanks are ringed by the cliffs of Twenty Mile canyon on the west and by those of the Similkameen canyon on the south. On the east, it slopes gently to the hanging valley of Eighteen Mile creek, and on the north, with only slight loss of elevation, it merges into the moderately hilly surface of the plateau.

Jan 1, 1941

By Jeffiey B. Austin, Maurice Tagami

"The ores of the Iberian Pynte Belt are typically massive sulphide ores with very fine grained mineral textures. EuroZinc Mining Corporation is currently evaluating one of the massive sulphide deposits located near the town of Aljustrel, in South Central Portugal. The deposit contains significant grades of lead, zinc and silver. The ores are comprised solely of sulphide mineralization consisting of pyrite, sphalerite, galena and some secondary copper minerals. Liberation requirements for these ores are typically 22 to 25 microns. A selective flotation process has been utilized to produce separate lead and zinc concentrates for sale to off-site contract smelters.This paper outlines the process test results and describes the process parameters required to optimize the process parameters. Ths test program has been conducted in support of the re-opening of the facilities in Aljustrel. The 3500 tpd mining and milling facility was commissioned in 1990 and operated for 18 months before closing. The previous facility was designed to produce three products using a selective copper-lead-zinc flotation process. EuroZinc Mining Corporation is proposing to re-open the operation, selectively mining from a lead-zinc phase of the massive sulphide deposit and produce only lead and zinc concentrates.Results are presented and discussed.PROJECT HISTORY AND CURRENT PROJECT OBJECTIVESThe EuroZinc Aljustrel Project is a potential major producer of lead, zinc and silver located in the Iberian Pyrite belt of south-central Portugal. The town of Aljustrel is historically associated with mining dating to the time of the Romans. The area is rich in pyrite deposits, and sections of the pyrite deposits contain significant zones of copper, lead, zinc and silver. Mining in Aljustrel during the last century (1900’s) included a major pyrite mining operation, which produced feed for sulphuric acid production. Pynte mining operated from the 1930’s to the early 1970’s and a short-lived base metal operation from 1989 to 199 1."

Jan 1, 2000

By L. W. Hamel

"Two 35 foot diameter enviro clear thickeners were tested in series as CCD units from June until October, 1978. Up to shutdown in July, we ran with automatic bed level control via the level probes and underflow pinch valves. Despite extensive efforts, we were unable to eliminate the surges created between the units by the opening and closing of the pinch valves. Early in July, the best rake speed and gap setting were determined. After shutdown, the enviro clears were run by manually controlling the pinch valves. These efforts were successful.A few mechanical problems were encountered while operating the thickeners. New units should incorporate more support for the drive coupling and a rubber feed seal. A few modifications of the instrumentation control scheme will be required before the units can be fully automated. A less sophisticated automatic flocculant addition system will accomplish the desired results. Control of the underflow withdrawal via the pinch valve should be investigated further. Our best results were obtained by keeping the feed volume to the No. 1 enviro clear constant. Surges were controlled by opening or closing both underflow valves proportionately.Capacity of the enviro clears is dependent of many variables. The ore treated during the test program was much finer than that reported on in R & D Project Report 76-02. Conditions were never steady enough to determine best flocculant dosage or addition point(s). The lowest soluble losses were obtained at very high wash rates. The underflow densities drop but the soluble losses also drop. Regression equations were developed in order to assess the effect of the various parameters. Within the range studied, these equations will predict the performance of enviro clear thickeners as CCD units on Elliot Lake ores. Our results show that the enviro clear thickeners are a viable alternative to the conventional CCD thickener."

Jan 1, 1979

By S. H. Ward

An account of a new method of investigating the electrical .properties J the earth's crust is presented. The method, called AFMAG, employs, as a source, natural alternating magnetic fields of audio and sub-audio frequencies. Measurements of the distortion of these fields caused by geological features are made with the aid of search coil detectors at several discrete frequencies. Many results of field surveys made with the method are presented and they illustrate its advantages and limitations when applied to the search for massive sulphide mineralization. The advantages far outweigh the limitations and in fact indicate that a major breakthrough in geophysical exploration technique and instrumentation has been made.

Jan 1, 1958

By James Pirie

"The major Archean gold deposits in the Red Lake greenstone belt, which have produced over 374 million grams of gold since 1930, occur near the top of the lower komatiitic to tholeiitic mafic to ultramafic metavolcanic sequence. The upper calc-alkalic mafic to felsic rocks form three discrete and separate ediftces overlymg this lower sequence.The gold deposits are classified according to their stratigraphic or lithologic associations into:1) mafic-volcanic-hosted deposits;2) felsic-intrusive-hosted deposits; and3) stratabound deposits.Group 1 and to a lesser extent Group 2 deposits occur within zones of alteration several square kilometres in extent. The nature of this pervasive alteration can be characterized by comparison of petrochemical data from the altered rocks and their fresher equivalents some distance away. The altered rocks have substantial addition of SiO2> CO2, K2O, As and Sb and subtraction of Na20, CaO, MgO and total Fe. Cr, Ni, Co and Zr appear to have been relatively immobile. Hydrothermal alteration and gold deposition probably accompanied early fumarolic activity and continued during subsequent deformation the metavolcanic sequence, with gold eventually being mobtltzed and concentrated into major vein structures to form the present orebodies. The smaller Group 2 deposits formed by emplacement of felsic intrusions into already altered, anomalously gold-bearing mafic metavolcanics, with the heat from the intrusions setting up parasitic hydrothermal systems which mobilized the gold and deposited it along with minor sulphides in fractures in the cooling intrusions."

Jan 1, 1982

By Balakrishnan Nanthakumar, Marek Pawlik, Dennis Grimm

"The anionic flotation of a high-iron phosphate ore from Agrium - Kapuskasing Phosphate Operations was investigated through batch flotation tests in the presence of soda ash. The flotation data were supplemented by titration of the flotation pulp with soda ash, analysis of process water chemistry, and determination of the mineralogical composition of the ore. The results of lab tests were applied to the flotation circuit design allowing the flotation plant to efficiently process problematic ores. Process control measures (pH, conductivity) were also developed.Calcium cations and sulfate anions were identified as the dominant ions present in the process water when the difficult-to-process ores are beneficiated in the flotation plant. The concentrations of calcium and sulfate ions were consistent with the presence of a small amount of a calcium sulfate mineral in the ore although an oxidation/weathering process of iron sulfide minerals present in the ore could also be responsible for the observed water chemistry and subsequent flotation problems with the ores. The latter possibility suggests that the long-term stockpiling of such ores may have a highly negative impact on the flotation process.The role of soda ash in the flotation circuit is to precipitate metal cations from the pulp thus allowing the tall oil-based collector to selectively interact with the phosphate components.INTRODUCTIONPhosphorus minerals are the main source of this element for the production of fertilizers, and the froth flotation process is the most important technology for beneficiating phosphate ores. The flotation concentrate from Agrium-Kapuskasing Phosphate Operations (KPO) is transported to Redwater Fertilizer Operations in Alberta (also operated by Agrium) where the phosphate concentrate is converted into a phosphate fertilizer and other important chemical products. The KPO phosphate ores differ widely in mineralogy and phosphate grades, and are broadly divided on-site into three classes. The easy-to-float A-type ores do not pose any major flotation problems, but the B-type and “marginal” ores, which are quite common in the KPO igneous phosphate deposit, are not always readily-floatable using the current reagent suites and process parameters (pulp density, feed particle size, pH). In fact, marginal ores are presently considered impossible to process by flotation. A-type ores contain normally more than 15% P2O5 and less than 8% ferric oxide equivalent (Fe2O3). B-type ores are approximately of the same P2O5 grades as A-type ores but their iron content may reach 30% Fe2O3. Any material containing less than 15% P2O5 is rejected as waste rock."

Jan 1, 2008

By Staff

Introduction As the Sherritt Gordon property is still in the development stage, . it is rather difficult to write a proper account of the mining methods and milling practice that will be used. While the general scheme of operation will remain the same, there will undoubtedly be many minor changes to meet special conditions which we cannot forsee at the present time. Most of the work accomplished to date has followed the usual routine of preliminary development in the Canadian North. However, we have learned a few things which might be of use to others operating under similar conditions. The most important of these is the saving in power cost made possible by the use of Diesels as against steam power when using wood fuel, and the movement of freight by tractors when rail transportation is not available. Location The property i6 located about 90 miles north of The Pas, or 40 miles northeast of the Flin Flon mine. A branch line from Cranberry Portage, on the?C. N. railway, between Flin Flon and The Pas, connects the property with the outside.

Jan 1, 1930

By D. J. Hallbom

This paper presents a novel methodology for the hydraulic design of mine backfill distribution systems. The ?operating range? method uses the concepts of the hydraulic grade line and equivalent pipe length to determine flows and pressures as the pipeline route and static head change over the life of the mine. The operating range method is easy to learn because it is semi-graphical and uses well-known design concepts (e.g., the hydraulic grade line) and slurry design models (e.g., the Durand deposition velocity model). However, by changing the paradigm in which these concepts are used, the operating method allows all potential pipeline cases to be analysed simultaneously without the need to know the exact pipe routing. It also allows the hydraulics engineer to quickly identify ?pinch points? and ?slack flow? zones, to estimate the effect of changing the size or length of any given section of pipe, to assess the impact of changing the material properties of the backfill slurry, to size the slurry pumps, and to size and locate rupture discs when required.

May 1, 2007

By E. G. Kearnery

Introduction It is believed that the present paper will be of some interest, not because of any outstanding features of Renabie milling practice but because Renabie is the first gold mining property in a newly explored area - in Leeson and Rennie townships, Sudbury district, Ontario - to reach the production stage. The Renabie mill was originally designed by the General Engineering Company (Canada), Limited, as a 300-ton plant and went into operation in June, 1947, treating an average of only 128 tons a day for the balance of that year. Toward the end of 1948 the capacity of the plant was expanded to 450 tons a day, and the tonnage treated was gradually increased from the 1947 figure to the point where 420 tons a day was averaged for the first nine months of 1949. Description of Ore In general, the outstanding gangue component of Renabie ore is white quartz, which comprises at least 80 per cent of its total bulk and in some sections considerably more. Virtually all the gold occurs in very finely divided state; only very rarely has free gold coarser than 325 mesh been observed. The ore has a very low sulphide content, ranging from about 0.50 to 1.00 per cent by weight. The gold occurs both free in the gangue and ? locked in sulphides, the proportion of one to the other varying considerably from one orebody to the other. Pyrite is by far the most abundant sulphide, followed by galena, which, however, appears to be entirely absent in some of the orebodies. Minor amounts of pyrrhotite, chalcopyrite, chalcocite, and sphalerite have been noted. The ore appears to be entirely free, or almost so, of minerals containing arsenic, antimony, or molybdenum, and in general it could be described as free milling. The various hindrances to extraction of the gold which have been met with are believed to be due largely to the very finely divided state of the metal and to its intimate association with the sulphides and gangue. The ore contains silver, with the gold-silver ratio about 3:1.

Jan 1, 1950

By Glen A. White

The level of impact and mitigating measures that are forecast in an environmental assessment (EA) for a new, or significantly modified, metallurgical processing facility or mine are taking on increasing importance during the subsequent life of the facility. The basic premise is that one is authorized to operate within the envelope defined by the approved EA. Operations inevitably change as they develop and mature, and at some point, one is faced with the prospect of re-doing the original EA work. This can lead to significant development delays. Cameco Corporation (Cameco) has played a major role in developing the northern Saskatchewan uranium mining industry over the past decade. Through the EA process, the company has developed ideas on what works well in generating approvals that give the operator some future flexibility. Early introduction of concepts for potentially different mining and processing methods, as well as contingency plans if things do not work out exactly as predicted in the original EA, can make subsequent regulatory approval for change a more efficient process. One must also preserve the principles of open consultation upon which the EA process was originally based. As such, involvement and support from local communities and other stakeholders is required to ensure the long-term success of the EA process.

May 1, 2004

By Jos. Kalbhenn

PART of the plan of re-allocation evolved by the engineers of the Dominion Steel and Coal Corporation in 1932 to retard the rapid advance of the submarine workings seawards was the opening of Dominion No. 20 Colliery, in the Harbour seam, by a pair of cross-measure tunnels from the workings of an older mine working the Phelan seam, which lies 430 feet below the Harbour seam. The tunnels, 8 ft. by 13 ft. in size, were started away from the old workings of Dominion No. 2 at a point 1.5 miles beyond the shore line and were driven on a rising grade of 1 per cent for a distance of 5,335 feet, tapping the Harbour seam at a point 2 ¼ miles off-shore. For transportation and ventilation, shafts and roadways already existing in the Phelan seam were made use of during the stages of development and up to the present time. One of the two tunnels served as a main haulage road and an intake airway, and the other as a return airway and travelling road. However, as the workings of this new colliery expanded, the need for additional airways arose as was anticipated when the plans for the development were formulated. To meet this need, work was started on October 1st, 1942, to establish a new opening between Nos. 2 and 20 Collieries in the form of a vertical shaft to provide a passageway for the ventilating air current of some 250,000 cubic feet per minute on its return to the upcast shafts in No. 2 Colliery, thus making both tunnels available for intake airways. In the interest of safety, speed, and economy, the shaft was raised from the Phelan to the Harbour seam. It is 20 ft. by 12 ft. in size and, with the exception of three timbered compartments across the narrow end, is untimbered. One of the three timbered compartments housed the ventilating tubing and pipe lines, the centre one served as a cage-way for hoisting men and material during the operation of raising, and the third one contained a ladder way. The rest of the shaft was filled with debris during the period of shaft raising.

Jan 1, 1944

By G. H. Charlewood, J. W. McBean

"One hundred years after being developed, the diamond drill is still an essential tool in mineral exploration. The basic principle is unchanged, but the technique has been revolutionized, particularly in the past fifteen years. The cost of core drilling has not kept pace with the rising cost of living. The price of machinery, supplies and labour in drilling has doubled and trebled since 1946. Some of the techniques which have made it possible to hold the price line are described."

Jan 1, 1967

By A. Bamber

Canadian leadership in a global mining context will depend not only on entrepreneurship and best practice but also on technological innovation. This paper argues for more ambition and commitment to R&D for technological innovation in Canadian mining. It focuses on underground hardrock mining, where past R&D initiatives have simply not stood the test of time, and it is important to examine why. Concerns arise because industry’s commitment to R&D has not been sustained over time. Innovation through exploration, processing, and environmental technologies has been more significant. Meanwhile, R&D capacity and synergies in government institutions and universities have not been exploited. There is a need for more commitment, coordination, and collaboration by industry, governments, and universities. This paper examines some corporate models that have achieved sustainable innovation, along with some that have not. A strategy for innovation is discussed that relates to culture, commitment, coordination, and collaboration.

Jan 1, 2005

By Ish Grewal

The ACACIA Reactor - Introduction What is it? The Acacia Reactor is a fluidized bed high intensity cyanide leaching system. Purpose for its existence? The Acacia Reactor was developed to treat high grade gold concentrates generated from primary gravity concentration systems. Why intensively cyanide leach a gravity concentrate? Current secondary upgrading processes, such as tabling, create significant losses of fine gold that is initially recovered in the primary gravity concentration units. Additional benefits include improved security and a reduction in health hazards associated with calcining.

May 1, 2002

By J. E. Dutrizac, J. B. O'Reilly

"Zinc is a relatively abundant element which occurs as both high-grade sulphide ores {sphalerite ZnS) and oxide ores which the ancients collectively termed ""calamine"" (smithsonite ZnC03 and/ or hemimorphite Zn4Si201(0H)2 - H20 and/ or hydrozincite Zn5(C03) 2(0H)6). Although oxidic zinc is readily reduced by carbon, the process becomes thermodynamically viable only at - 1000°C, and at this temperature the zinc is released as a vapour (B.P. 907°C). Casual cooling of the vapour results in its re-oxidation by excess combustion air or even the carbon monoxide product of the reduction reaction. ZnO + C = C09,, + Zn vapom Only fairly rapid quenching of the zinc vapour and the isolation of the reduction products from the combustion gases will yield metallic zinc; these conditions were not produced deliberately until the advent of distillation technology. Until quite recently, the principal use of zinc was in brass manufacture; galvanized iron was not discovered until the 19th century and zinc casting alloys are a relatively recent invention. As will be seen, brass could be produced without recourse to a pure zinc intermediary, and the discovery of brass preceded that of zinc by many centuries. The purpose of this paper is to outline the discovery and early development of both zinc and brass with special reference to the European scene."

Jan 1, 1999

CORPORATE SOCIAL RESPONSIBILITY CSR is about how companies manage the business processes to produce an overall positive impact on society. - Indentured work, sexual slavery, fair trade, organic growing, business ethics, environmental issues, ?Right to know -Right to decide?, AIDS activism, civil society - Balancing stakeholder issues - Government responses Who are the bad guys? Where are the threats?

May 1, 2010

By The Honourable George Prudham

"I AM PLEASED indeed to be present with you here today and to be taking part in the proceedings of your convention. You have been greeted and welcomed to the Province by Premier Manning who is also provincial Minister of Mines and Minerals, and to this City by Mayor Hawrelak. As Minister of Mines and Technical Surveys in the federal government and as Member of Parliament for Edmonton West, I have been asked to share the honour of extending greetings and a cordial welcome to all.It is a happy coincidence that this representative national gathering, indicative of the growing strength and significance of a great basic Canadian industry, is taking place in the Macdonald Hotel, the new addition of which marks another important step forward in the progress of this City and district.This happens to be the third national convention of the C.I.M. that I •have had the pleasure of attending and I trust that I am not presumptuous in expressing the hope that I will have the opportunity of attending many more conventions of the Institute in my present capacity.Dr. Kidd has bestowed on me a high honour by asking me to be Co-Chairman of this Inaugural Session of the Convention and thus to share with him the responsibility of presiding over the proceedings of this afternoon."

Jan 1, 1953

By F. D. Forgeron

"ONE OF THE FIRST DOCUMENTED APPLICATIONS of soil geochemistry in the Canadian Shield was that carried out by Chisholm in the Kenora district in 1949. This survey proved successful in outlining sulphide-associated gold veins utilizing cold-extractable metals. Since then, mining companies, government agencies - both provincial and federal - and universities have conducted soil investigations. Some of the results are documented in publications, others are on open file in provincial and federal mines departments and, unfortunately, many other investigations with both successful and unsuccessful results are buried in company files or have been discarded. This paper deals with soils within the scope of chemical studies of overburden in the Canadian Shield. The subject is a broad one and some definition is required. The soil investigations discussed herein are those aimed at the testing of specific targets more or less in the source area. This definition distinguishes soil investigations from other overburden studies which commonly monitor metal accumulations at some substantial distance from the metal source. Naturally this distinction is relative, because in many instances there is overlap."

Jan 1, 1971