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By V. Aprahamian, T. Cheng, M. Tangen, R. Beauprie

The Royal Canadian Mint has implemented significant process additions since 2005. Installation of a whole new highly automated silver refining circuit has allowed recovery of physical silver from gold and silver dorés . To complement this change, a small Top Blown Rotary Converter has been in operation. On the gold refining side, a new hydrometallurgical process to recover precious metals from Miller Chlorination slag has been developed. Finally, new systems have been put in place to improve treatment of waste water, wet and dry fume and dust.

Jan 1, 2011

By A. H. Winckers

"CAMIRO, The Canadian Mining Industry Research Organization, formerly known as MITEC, is a collaborative research organization of Canadian Mining Companies. It is comprised of Exploration, Metallurgical Processing and Mining Divisions.The Metallurgical Processing Division (MPD) has the mandate to contribute to the profitability, competitiveness, safety and growth of the Canadian mining industry by improving the efficiency and effectiveness of mineral processing and extractive metallurgy in an environmentally conscious manner through the development of innovative technology by managing cooperative industry focused research programs.Current membership includes about ten Canadian mining companies. Past research has largely focused on base metal mineral processing. The Division wants to expand its research base to include all areas of mineral processing and extractive metallurgy.Past performance and plans for the future will be highlighted in the presentation."

Jan 1, 1998

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the LaJoya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein(BPV) type, with a signi?cant amount of the gold reserves contained in the oxide cap.Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"Abstract - The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the La Joya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein (BPV) type, with a significant amount of the gold reserves contained in the oxide cap. Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By M. Dupuis

In the present study, the heat balance of the Hirakud smelter aluminium reduction cell has been accurately assessed using only a surface thermocouple and a pyrometer, As it is well known that using a single linear or quadratic relationship to estimate the heat flux from the measured surface temperature does not provide the accuracy required to close the cell heat balance, this approach was not used in this study, Instead, the fundamental natural convection and radiation heat flux equations were used systematically for each measurement point, Practically, this means that the ambient air temperature and at least one ambient radiative temperature must also be known in addition to the surface temperature for each measurement point. Sometimes, the radiative heat flux could not be accurately estimated using a single ambient radiative temperature, In those cases, a more accurate estimation based on two ambient radiative temperatures and corresponding view factors has been used instead, It turns out that although at least three temperature measurements are required to estimate a single heat flux, it takes a lot less time to make those temperature measurements using a pyrometer than directly measuring the heat flux using an expensive heat flux meter, Furthermore, no loss in accuracy was detected when using this approach as the cell heat balance could be closed within 5%, the level of accuracy typical of cell heat balance assessment using heat flux meter.

Jan 1, 2004

By D. R. Pyke, R. S. Middleton

"Three main types of base metal sulphide mineralization are present in the Timmins area:(1) -Massive and stringer-type copper-zinc deposits occurring mainly in pyroclastic rocks, as typified by the mines of Kam-Kotia, Jameland and Canadian Jamieson, or within or close to possible breccia pipes as shown by the Genex and Kidd Creek mines. With the exception of the Kidd Creek mine, all of these orebodies occur northwest of Timmins (Kamiskotia area) and appear to lie within or close to a major center of volcanic activity characterized by a thick accumulation of felsic pyroclastic rocks and subordinate epizonal intrusions. The margins of the rhyolitic pile are interfingered with mafic volcanics; overlying sedi-ments mark the termination of a vol-canic cycle. The copper-zinc deposits in the Kamiskotia area are confined to a particular stratigraphic unit. Ore-bearing solutions were probably derived from the intrusive complex of the volcanic pile.(2) -Porphyry copper deposit of the Mcintyre mine. The deposit occurs in a quarz porphyry intrusion related to the volcanism in the area (Hurst, 1936). Mineralization was probably introduced at the time of intrusion, and subsequently redistributed within the porphyry during deformation. (3) -Massive and disseminated nickel mineralization, associated with serpentinized alpine-type ultramafic intrusions, as shown by the Alexo, McWatters, Hart, Inco and Texmont deposits. The nickel mineralization occurs at or near contacts of the serpentinites with felsic or mafic volcanics, or sulphide-bearing iron formations. The nickel deposits south of Timmins are confined to a particular stratigraphic unit along the margins of domical-shaped structures which appear to outline former volcanic centers. Sulphurization as pro-posed by Naldrett (1966) appears to be a workable hypothesis for the formation of some of the deposits."

Jan 1, 1971

By M. F. Almeida

"Due to the randomness of all factors influencing the sintering operation, a two-stepped procedure is proposed to find the best way of using stocked fines at a plant producing Fe-Mn alloys for the steelmaking industry. The approach is based on the following: (1) predict the result of the sintering operation by establishing the best multilinear regression model using some of the characteristics of the loaded material; and (2) find the best solution under a minimizing cost criteria by solving a linear optimization problem using the regression equation plus constraints on the feed and product. IntroductionSome tests carried out using 20% to 30% of sinter in the material loaded into a 60 000 KVA Tysland-Hole electric furnace producing Fe-Mn alloys for the steelmaking industry indicated: (1) a meaningful decrease in the off-gas temperature and, consequently, a better energy use due to the material higher porosity; (2) more uniform heat distribution as a consequence of the electrode reaction zone enlargement; (3) an improved furnace control resulting in a smoother operation; and (4) a decrease in gas production facilitating the off-gas treatment. For some years, this plant used only the coarse fraction of the Mn ores, thus stocking all the received and own-generated fine particles. In view of the mentioned results, a strategy for increasing the use of stocked fines was formulated, including a step where it was necessary to decide which components and respective quantities should be used in the blends to be sintered (Almeida, 1984).It is well known that several factors affect productivity and energy consumption in sinter production, also influencing the product quality. Raw materials characteristics, namely chemical and size composition, affect permeability to gases and may or may not allow a deeper bed. In general, finer ores decrease permeability, increasing electricity consumption by fans, but due to their higher specific surface area, react more completely with other components in the mixture. For coke granulometry, a compromise must be obtained in order not to burn it too quickly nor to widen the flame front, therefore decreasing productivity. Decreasing coke in the blend also acts in sinter bonding, decreasing its consistency and increasing crushing and return fines. Moisture addition also influences components mixing, pre-agglomeration, bed permeability and, consequently, sintering productivity. Therefore, optimum conditions must be established for both a given sintering plant and the components in the feed (Dawson, 1993)."

Jan 1, 1998

By L. Newman, R. Wyrick, R. Berezowsky

The Stillwater Mining Company operates an integrated mines, mill, smelter and base metals refinery complex in Montana, USA for the production of a high-grade platinum group metals (PGM) bearing concentrate, nickel sulphate crystal and cathode copper from the PGM-containing nickel-copper converter matte. The complex was constructed in stages over several years, starting with the mine and the mill, followed by the smelter and finally, a base metals refinery, which was commissioned in 1996. Due to the relatively small quantity of matte production, a straightforward refinery process was initially selected to extract the base metals, which reported to a mixed nickel-copper solution for further treatment off-site, and yielded a high-grade PGM concentrate suitable for treatment in a PGM refinery elsewhere. Subsequently, as a result of increased matte production, the process was modified to separate the nickel and copper, and to produce a nickel sulphate salt and cathode copper. This paper describes the design and operation of the original and the modified processes utilized in the base metals refinery (BMR).

Jan 1, 2004

By David Runnels

The Mount Wright iron are mine and upgrading plant were brought on line in the fall of 1975. The mine is located near the Quebec - Labrador border some six hundred miles northeast of Montreal. This paper describes the crushing, grinding and concentrating facilities at Mount Wright, and some design: criteria used in equipment selection and flow sheet design. Also mentioned are some "asbuilt" modifications. A brief description of the over-all flowsheet is also included. Introduction IN SEPTEMBER 1970, the Quebec Cartier Mining Company started development of the Mount Wright iron ore mine. The estimated are reserve is in excess of 1,000,000 ,000 long tons of concentrates, with an average crude are grade of 31.5% Fe. The run-of-mine ore is crushed, ground and concentrated to a product having 66% Fe and 5% silica at an annual concentrate production r ate of 18.4 million long tons. The daily production rate of over 50,000 long tons of concentrate necessitates a daily mine output of approximately 250,000 long tons of material, of which 50% is waste.

Jan 1, 1977

By John J. Laffin

"Nova Scotia Department of Mines and Energy Throughout the history of Nova Scotia, trends in the production and use of its coal resources have resulted in major impacts on the economy and society of the province. Current trends in coal demand locally, nationally and internationally are having and will have an increasing positive effect on Nova Scotia over the next twenty years-in terms of energy supply, job creation and general economic development. Coal for electrical generation is an immediate and key objective of Nova Scotia's energy plan; and, in the long term, coal-derived fuels will meet the province's needs for transportation fuels. Demand for metallurgical coal is also expected to increase, especially if the merchant coke plant currently under investigation becomes a reality.Meeting these coal supply and utilization objectives in the face of increasing environmental, social and economic constraints poses a tremendous technical challenge. Work has begun on projects to expand coal production capacity and to adapt new technologies for coal preparation and utilization to the specific needs of Nova Scotia; much more work will be required in the coming decade in order to succesfully tap this resource.IntroductionThe energy problem facing Atlantic Canada has a few unique features not found in the rest of the country. Canada, as a whole, has access to a diverse mix of energy resources, including crude oil, natural gas, coal, hydro and uranium, with the result that crude oil supplies only about 40 per cent of Canada's primary demand. In contrast, foreign crude oil dominates Atlantic Canada's energy mix, supplying over 70 per cent of the primary energy demand.This results in important differences in various sectors. Nationally, about 5 per cent of the electricity is generated from oil whereas last year in Nova Scotia approximately 40 per cent of the electricity generated was from imported oil. Residential, commercial and industrial space heating, and industrial process heating in Atlantic Canada was almost 100 percent dependent on foreign oil. This is in sharp contrast to the situation in central and western Canada, which have access to secure domestic natural gas, oil and hydro electricity."

Jan 1, 1982

By W. M. Armstrong, John A. H Lund

The paper describes an investigation of some of the tensile properties of single crystal vanadium, poly-crystalline vanadium and polycrystal-line tantalum, in the range of: W°C to -196°C. Techniques employed in the preparation and testing of specimens are discussed in detail. Some results of determinations of the temperature dependence of yield stress and ductility are given, and discussed in terms of the Cottrell-Bilby Theory of yielding. At subnormal temperatures, all the body-centred cubic transition metals in the Periodic Table exhibit; a) the "yield phenomenon" in tension, b) a strong temperature and strain rate dependence of yield stress, and c) a large decrease or complete loss of ductility. The yield phenomenon (existence of an upper and lower yield point) has been explained by Cottrell and Bilby ( 1) in terms of the dislocation-locking effect

Jan 1, 1961

By E. O. Magnusson

THE orebodies of the Preston East Dome mine show a considerable variation in size,? shape, dip, and ground condition. They vary from small and large irregular masses being mined by shrinkage, cut-and-fill, and square set-and-fill mining methods to narrow veins being mined by open stoping. Standardization of mining operations has necessarily been difficult. This considerable variation in mining condition prompted the development of a bonus system which would give more equitable bonus payments through-out the mine than those obtained by the usually accepted methods of calculating mine bonus. PRINCIPLES ON WHICH THE SYSTEM IS BASED Under an incentive bonus system, performance (efficiency) and a price per unit of work done are inter-related. It is in the application of this? principle to working conditions .in the Preston East Dome mine that the system to be described differs from the standard methods of calculating mine bonus. It was found that the method of paying a fixed price per unit of work done, under the 'contract' system, gave satisfactory results in development, less satisfactory results in timbering, and results which were not satisfactory in stoping. Under the fixed price system, bonus payments, in timbering and stoping particularly, were very erratic and did not necessarily represent fair payment for the work done. A fixed price in development is satisfactory because the work done, and the conditions under which the work is done, are uniform. The drilling and blasting cycle is completed in one shift, the size of heading is con-trolled, and a minimum number of holes are required in order to obtain a satisfactory break. The performance possible under these conditions has been found to be confined to a fairly narrow range. By performance in development is meant the efficiency of the working crew as expressed in terms of the two variables of feet of advance per round and pounds of ex-plosives consumed per foot of advance. A change in rock formation, how-ever, may alter to a marked degree the performance possible, quite independent of the skill and energy of the working crew. The changes in working conditions that affect development performance from the standpoint of bonus calculation are usually easily apparent and are satisfactorily met by establishing several fixed prices.

Jan 1, 1944

By E. B. Wilson

"Although the Operations Research technique of Reliability Theory has been applied with marked success in many fields, including the Apollo spaceship programs, the concept of reliability has not been generally adopted in mining and other heavy industries. Of course, reliability, or the probability that a system will be able to operate without a failure for a given interval of time, does not require the same emphasis in mining as in the aerospace industries. Nevertheless, certain aspects of Reliability Theory can be followed advantageously. For example, reliability calculations can determine the best time to overhaul and whether to retain stand-by units.The usefulness of the pseudo-operations research technique known as Replacement Theory is more readily re-cognized by the maintenance engineers in mining and other heavy industries. One of the least complex models enables the optimum Lifetime of an asset to be determined."

Jan 1, 1970

By Eldon L. Brown

Location and History The Sherritt Gordon property is located in northwestern Manitoba, about 100 miles north of The Pas and 40 miles northeast of Flin Flon. It is connected with the Manitoba Northern railway, which runs from The Pas to Flin Flon by a branch line, 42 miles in length. The location of the property is shown on the sketch-map, Figure 2. The ore deposit was first discovered by Philip Sherlett, a Cree Indian, in 1922. In 1924 Sherlett's claims lapsed and the ground was re-staked by Carl Sherritt and Dick Madole, and was optioned by them to J. P. Gordon in the summer of 1925. Gordon re-optioned the property successively to three well-known mining groups, one of which did some surface trenching .and put down 28 shallow diamond-drill holes before dropping their option. In the latter part of 1927, a Company known as Sherritt Gordon Mines, Limited, was formed to take over the property, and preparations were made for systematic development work. Preliminary Development In order to fill-in gaps left by the original drilling, a light diamond-drill outfit was flown-in to the property from the Hudson Bay railway in the early fall of 1927. Ten shallow holes were put down before freeze-up .and a considerable amount of surface trenching was completed. Based on the results of the surface trenching and the shallow diamond-drilling, an extensive development campaign was outlined. A winter road, 90 miles in length, was cut from mileage 55 on the Hudson Bay railway, and during the winter of 1927-28 a total of 2,600 tons of freight was hauled-in to the property. This freight included four complete diamond-drill outfits, two complete mining plants, building material for two sets of camps, and supplies for one year's operations, including 105,000 gallons of fuel-oil for Diesel engines.

Jan 1, 1933

By C. O. Aksoy, P. M. Ozfirat, M. K. Ozfirat, C. Tatar, C. Pamukcu

"Temporal and other factors contributing to the occurrence of occupational accidents at an underground coal mine in Turkey between 1992 and 2000 have been analyzed. The time period of the study spanned the transition from hand-worked mining methods (1992 to 1996) to hand-worked mining methods and mechanized mining methods (1997 to 2000).The mine selected for the study employed an average of 5,835 men per year on three separate eight-hour production shifts for 302 d/y (Sundays are not worked, and there are 11 holiday days per year). Production on an annual basis averaged 190,000 tons per year between 1992 and 1996, and 300,000 tons per year between 1997 and 2000.The purpose of the study was to determine which, if any, of the factors studied contributed to the occurrence of accidents so that the mine could take the necessary steps to reduce the risk to the workforce. Regression analysis was used to determine the strength of the relationship between each factor studied and the number of occupational accidents.The strongest relationships observed were between the age of the employee, the day of the week, and the total yearly labour."

Jan 1, 2006

By B. Krysa, J. Qiu

The zinc pressure leach plant at HBM&S's operations is now in its fifteenth year of operation. Current pressure leach operation is steady at a concentrate processing rate of around 26.5 tonnes per hour. A new cellhouse with a design capacity of 124,000 tonnes per annum and the capability of expansion of up to 154,000 tonnes per annum was commissioned in July 2001. The potential to expand the capacity of the pressure leach circuit and associated processes, as well as the purification circuit and casting plant, to meet the maximum capacity of the cellhouse has been investigated. This paper reviews current operation of the zinc plant, as well as the possibility of a capacity increase without major process modifications or major capital expenditures.

Jan 1, 2008

By H. P. Pew

THE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by T HE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by 85 miles wide, is the largest in Canada in areal extent, in the amount of oil in place and in the current producing rate. The discovery well was completed in the middle of 1953. The field has grown until its present area is 369,820 acres. There are 74 working interest owners in the field. Early in the producing history of the Pembina field a committee of operators was formed on a permanent basis. The Pembina Operators' Committee has established a permanent staff, which compiles and distributes pertinent field information on a regular basis to all participants. The Alberta Oil and Gas Conservation Board has dealt with field-wide problems primarily through this committee. Expansion of the field was rapid as shown by the number of wells completed -from 135

Jan 1, 1961

By Mathieu Dubé

Good mechanical strength of green iron ore pellets is required to avoid breakage and excessive deformation during their handling and further processing. However, green balls with good resistance to handling are often too plastic, which impacts the bed permeability in induration furnaces. Measurements of plasticity, bed void fraction and green ball sphericity as well as bed permeability were carried out on various samples of green iron ore pellets having different mechanical strength. Results show that bed void fraction, sphericity and permeability all depend, to some extent, upon green ball mechanical strength (plasticity). Understanding and controlling the mechanical strength of green iron ore pellets would then help to maximize both the productivity of the induration process as well as the quality of fired pellets through a more stable firing process. Results of research work carried out at COREM, with the objective of improving green ball characterization methods, are presented in this paper.

May 1, 2007

By H. G. Stephenson, C. W. Gregory

"This article describes the methods used for pillar extraction in the Wilson Seam at Canmore Mines, Alberta. The Wilson Seam is extremely gassy and varies in thickness between 7 and 30 ft, with an average of 12 ft. The gradient varies from 5 to 30 degrees, with an average of 15 degrees. The seam was developed using Lee Norse miners to form pillars which the company intended to extract using the same machines. Before pillar extraction commenced, an abandoned and inaccessible mine 160 ft above the Wilson had to be drained of 360 million gallons of water. When this was done pillar extraction commenced. Conditions in the mine slowly deteriorated and after 6 months the decision to withdraw the continuous miners was taken. Slusher hoists were installed to replace the continuous miners, with the result that roof conditions and safety steadily improved."

Jan 1, 1972

By Robert S. Penczak

Red Lake Gold Deposits ? Descriptive Classification (modified from Pirie, 1982) VHR Au -- Volcanic-hosted (vein & wall-rock) replacement Au deposits ~93% of camp production Q-(T) Au -- Quartz-(tourmaline) vein Au deposits ~7% of camp production Quartz-sulphide Au deposits Porphyry-hosted sulphide Au deposits Current & Significant Past Producers Camp Production 21.6 M oz / 672 tonnes Au Other Deposits / Occurrences (Intermittent Exploration

Apr 1, 2005