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Most of automotive magnesium applications are presently produced by high-pressure die casting processes, For further expansion of the alloy usage in automobiles, novel-manufacturing processes needs to be developed, In this study, squeeze casting of AM50 alloy was carried out using a hydraulic press with an applied pressure of 70 MPa, Tensile properties and fracture behavior of the squeeze-cast AM50 were characterized in comparison with the die cast counterpart, The squeeze-cast AM50 alloy exhibits virtually no porosity in the microstructure evaluated by optical microscopy, The results of tensile testing indicate that the improved tensile properties for the squeeze-cast samples over the conventional high-pressure die-cast parts, The analysis of tensile behavior shows that the strain-hardening rate during the plastic deformation of the squeeze-cast specimens is constantly higher than that of the die-cast specimens. The SEM fractography evidently reveals the ductile fracture features of the squeeze-cast alloy AM50.

Jan 1, 2005

By L. Becze, B. Pierre, S. Di Carlo, G. P. Demopoulos

From January to June 2007, the autoclave production at the Kidd Metallurgical Site was severely affected as a result of plugged discharge lines and extensive precipitation/crystallization of sulphates that caused massive scaling in different autoclave compartments. Work was performed at McGill University to understand the root causes. The crystallization of zinc and ferrous sulphate salts was investigated in terms of solubility measurements. Scale samples were characterized using chemical and mineralogical-spectroscopic analysis. In this paper, following a description of the Kidd zinc pressure leach operation, highlights from this investigation are presented and solutions used to overcome the problem are outlined.

Jan 1, 2008

By Stanley G. Butcher

"Introduction Many operators in western Canada, with a background in the minerals industry, talk of ""coal beneficiation"", whereas the coal industry generally uses the term ""coal preparation"" . The sophisticated cleaning circuits and thermal drying units found in western Canada makes the term beneficiation particularly appropriate. This chapter uses standard coal preparation terminology(l,2J and assumes general knowledge of coal preparation unit processes and equipment(3,4,5). The geologic setting and mining methods of western Canada, described elsewhere in this volume, present for preparation run-of-mine coals which have particular problems. As a result the cost of preparation is a higher proportion of the total minesite production costs than in other coal fields . Preparation requirements are determined by the types of coals being produced and the markets in which they are sold. Western Canadian coals have a low sulphur content and do not require cleaning on this account. Prepared coal from western Canada has to be shipped vast distances -to the Pacific Rim countries and Ontario in particular -and the savings in transport costs justify the high costs of preparation. Factors which dictate selection and operation of the preparation processes are: i) Market specifications and coal rank. ii) Size distribution of particles and particularly the liability of coal and refuse particles to degrade during handling and processing. iii) Quantity and characteristics of the associated refuse. iv) Washability characteristics (the distribution of particles by specific gravity within each size fraction). v) Surface characteristics of the fines. vi) Variability of the raw coal. Where the product (coal or discard) has a high fines content special consideration must be given to dewatering, the removal of surface moisture, to give acceptable handle ability characteristics. In the severe winter climate of the western foothills and mountains thermal drying is necessary to prevent freezing of washed coal in stockpiles and railcars."

Jan 1, 1985

By A. P. Sasmito

It is well known that underground miners are exposed to one of the most dangerous working environments on earth. As mine delve deeper, the geological factor, mine position and climate condition as well as heat generation from mining machine give rise to the mine operating temperature. This, in turn, has an adverse effect on the environment and thus leads to higher operating costs. Careful estimation and design of air flow rate, spray system, cooling load and additional ventilation auxiliary equipment are of importance to ensure safety, comfort and productivity whilst maintaining low operating cost. A computational fluid dynamics simulation approach is employed to examine underground mine ventilation in a 36 m cul-de-sac of tunnel of coal mine. The model predictions in the turbulent range were validated by comparison with published data. Different turbulence models were tested to select one that yields adequate accuracy and is computationally efficient. Effects of the following parameters are evaluated: tunnel geometry, air flow rate and inlet air temperature. The objective of the simulation is to arrive at an optimal strategy for ventilation and thermal comfort at low cost.

Aug 1, 2013

By S. Foged

Umicore and MWH jointly demonstrated that mechanical dewatering of goethite and neutralised tailings significantly increased the life of a 30 ha tailings pond and improved the operation of the pond. Umicore operates one of its zinc production plants in Balen, Belgium. As part of its production process, an excess of neutralised and goethite¬containing tailings is generated. These have historically been stored inside large lined ponds. As the storage area of the current goethite pond was nearing its capacity, Umicore studied the potential for an extension to the existing embankment. However, this extension would face intense regulatory scrutiny, because the environmental and safety impacts were considered important. Together with Umicore, MWH suggested and investigated an alternative treatment approach consisting of mechanical dewatering prior to storage. A feasibility study was prepared where wet storage was compared to dry storage. Differences in safety risks, environmental impacts and economic costs were outlined. The study demonstrated that the life of the tailings pond could be increased from 6 to 22 years, seriously reducing the environmental impacts and safety risks at no significantly higher cost than would have been incurred with the continued operation of the existing pond. The results of the study are presented in this paper.

Jan 1, 2006

By R. B. Harkness

Many of us are familiar with the history of oil in the Province of Ontario, but for the benefit of those who have never heard the story I will repeat it. In 185 7 J. H. Williams, of Hamilton, an old-country Scotchman, who had the advantage of experience gained from the primitive methods used for refining the oil collected at seepages in Roumania, heard of the "gum beds" along Black creek in Enniskillen township, Lambton county. He erected a small plant in the bush and refined illuminating oil, where the village of Old Springs now stands. The labor of collecting this thick ?gummy substance from the sluggish water of the creek, prompted him to dig a well, the next year ( 1858), in the hope of obtaining a greater quantity. When his excavation reached a gravel bed on top of the rock, oil, resembling "lubricating oil of commerce", rose several feet. Several of these wells were dug and his refining business flourished. The following year the Drake well, in Pennsylvania, was drilled into rock, resulting in an oil find which encouraged one James Shaw to make a similar attempt on Black creek. With a spring-pole drill he completed his well in the spring of 1861 to a depth of 160 feet, and at that depth struck a gusher that flowed uncontrolled for several days. Great excitement followed and the village of Oil Springs had a mushroom growth. The Petrolia field was discovered in 1865. Lick followed up the Thames with a spring-pole rig testing the formations along that river and discovered the original Bothwell field in 1865. During the sixties wells were drilled in many counties in southwestern Ontario.

Jan 1, 1924

By W. D. Watson

"Early in mine development at Quintette Coal Limited major problems were encountered with the fleets of primary equipment which seriously hampered production. These major fleets (cable shovels, hydraulic shovels, hydraulic drills and electric trucks) have consequently been the focal point of maintenance efforts. Some were prototypes in the Canadian mining scene and brought with them new concerns to test their skills. The problems were studied and the category and areas which were having the greatest impact on the reliability of the equipment were determined. Once defined, priorities were established and a program was initiated which was designed to accomplish a resolution. Resulting from implementation of this systematic approach, over the past three and one-half years, the fleets are now giving good reliability and industry standard availabilities. Along with these significant achievements, cost per operating hour on some of the equipment fleets has decreased substantially and continue a downtrend through 1987. This paper identifies the problems and describes the resolutions. IntroductionIn the early years of the mine development, Quintette Coal Limited (QCL) experienced production shortfalls due to problems with the major excavator and haulage fleets. A large fleet of hydraulic excavators had been purchased, and QCL was among the first northern users of all hydraulic blasthole drills. They were also using some prototype equipment and encountered problems which were not common on other types of equipment or were unknown.Because of these unique problems and lack of experience from other mines to draw on, an analytical approach was taken to areas and associated causes of the delays affecting the availability and reliability of equipment. This was done by dividing the equipment downtime into seven classifications of delays, i.e. maintenance, electrical, hydraulic, mechanical, damage, service and preventative maintenance, and tires; and then each was expressed as a percentage of total downtime. Subsequently each of the delay classification was divided into categories e.g. electrical to six categories - wheel motors, main alternator, relays, cards, no propel, lighting and 24 V system. Then, the basis for further study had been established.From this preliminary analysis of historic records, it was possible to determine the areas which were causing the majority of the downtime. These areas were then analyzed to evaluate causes and to determine possible solutions to the problem s. This paper addresses the major fleets, their problems and eventual solutions. Plea se bear in mind that the over-all objectives were to increase physical availability and reliability."

Jan 1, 1988

By F. K. McKean

Abstract A discussion of the difficulties involved in the production of a clean molybdenite concentrate introduces the paper. There is a brief description of the various methods for producing molybdenite that will fit marketing specifications, and it is shown how these methods are nor suited to the milling of ores containing small quantities of bismuth and copper. A process that was developed in the ore testing laboratories of the Bureau of Mines at Ottawa for the La Corne mill of the Molybdenite Corporation of Canada is described in derail and some results from pilot plant operation of this milling scheme are tabulated. A description of the La Corne mill, where the writer supervised the introduction of the process on a commercial scale, adds to the interest of the paper. In conclusion, there is a review of the conditions necessary for proper operation of the flowsheet. An attempt is made to show how the process might be satisfactory in other problems similar to that at the La Corne mill. Introduction The production of a molybdenite concentrate, free from impurities and high in grade, has been a difficult task when milling some types of ore. Whereas ordinary flotation techniques will produce acceptable concentrates of the baser sulphides, in many cases they will not serve in the treatment of molybdenite, for this mineral must be of optimum grade and purity to bring the best prices, or to find a market at all . Faced with the necessity of meeting stringent specifications, the mill operator has been forced to employ expensive processing methods, and to be satisfied with low recoveries, in order to make grade with his product. The most objectionable and common impurities found with molybdenite are: (a) gangue minerals and iron sulphides, which lower the grade; and (b) copper, bismuth, or antimony, which are deleterious in the final uses of the molybdenite products. It is difficult, and sometimes impossible, to market a concentrate with over 0.5 per cent of any of the latter impurities, or with a grade much below 90 per cent MoS2. Various methods, which have been highly successful in specific applications, have been developed to meet the problem of producing a suitable concentrate. All of them, however, have certain defects precluding their use when treating ores of a nature different from the one for which they ? were designed. The writer has developed a process for molybdenite ores having an objectionable impurity content. A description of the procedure involved, and of the La Corne mill of the Molybdenite Corporation of Canada, where the process has been adopted, should be of interest to flotation operators.

Jan 1, 1947

By J. D. Wright

This paper describes current milling practice at Endako Mines Ltd., a molybdenum producer in central British Columbia. The various steps in the crushing, grinding and flotation of the ore are outlined, with emphasis on the metallurgy of the latter operation. Tailings disposal and concentrate assaying methods are also described.

Jan 1, 1969

By James G. Lyons

All machines vibrate and make noise. An increase signals impending trouble. Vibration and noise analysis allows the condition of the machine to be determined without costly interruption in service for disassembly and physical inspection.

Jan 1, 1977

By W. G. Hubler

It has been within only the last two or three years that enough progress has been made in preferential flotation to warrant metallurgists in recommending the installation of commercial-sized plants for the treatment of copper-zinc-iron ores. Until the new processes had been worked out successfully, the treatment of this type of ore had proved a stumbling block in the path of metallurgical progress. Separation of lead-zinc ore is comparatively simple. A lead-zinc ore low in iron may be separated and concentrated by gravity con-centration, provided it is not necessary to grind too fine. Owing to the specific gravity of chalcopyrite and sphalerite being so nearly the same, however, their separation by gravity concentration is out of the question. Complex lead-zinc-iron ores in which the several minerals are intimately associated, requiring fine grinding to free them, have been successfully treated by flotation for the past fifteen years. Galena is easily floated, and its flotation, unlike that of chal¬copyrite, is not affected by the reagents used to inhibit the flotation of sphalerite and iron sulphides. When an attempt was made to use the methods of lead-zinc se-paration on copper-zinc ores, it was found that the depressant re-agents added to inhibit the flotation of the iron and zinc minerals would, under certain conditions, depress a large part of the copper. It was also recognized that, in the grinding of copper-zinc ore, soluble salts were generated which were detrimental to flotation unless properly controlled. The main part of this paper will be a discussion of solutions in the grinding circuit in relation to the pro¬duction of soluble salts and their effect on flotation.

Jan 1, 1931

By E. L. Martheleur

A general expression for the electric power generated or consumed in a direct-current circuit is obtained by multiplying the reading of a suitable voltmeter connected across the terminals by the reading of an ammeter connected in the circuit. by the reading of an ammeter connected in the circuit. When alternating currents are considered, the product of the volts and amperes as obtained for direct currents does not generally represent the true energy involved; it is greater than this true energy and should be multiplied by a certain factor which may have any value between zero and unity, according to the conditions of the circuit. This factor is called the power-factor of the system, and expresses the ratio of the true energy over the apparent energy. For a three-phase system the expression of the apparent energy is [\/ 3 x E x I; ] while the expression of the true energy, that is, energy suitable for mechanical work, is [v? 3 x E x I x cos A.] The total current of a circuit corresponds to the reading of an ammeter connected in the circuit; it is the resultant of two currents. The first of these is in phase with the voltage, and is that portion which really produces mechanical work; the second is always in quadrature with the voltage, that is it may lead or lag the voltage by 90° according to the condition of the circuit. This second current does not produce any sensible work, and for this reason is sometimes called wattless current or reactive current.

Jan 1, 1924

By J. R. MacDonald

MINING literature contains very few descriptions of operations producing as little as 25 to 30 tons of ore per day. The purpose of this paper is to discuss the gradual development of a mining method for such a small-scale operation at the No. 2 mine of Central Patricia Gold Mines, Limited, and in doing so to review several systems of stoping applicable to narrow ve1ns. MAIN ECONOMIC FACTORS TO BE CONSIDERED (1) Overhead.-The outstanding feature of most mines operating on a single narrow vein is chat of small daily tonnage. The reason for this low output can be readily understood. The strictly limited ore-reserves present a condition unfavourable for a policy of large initial expenditures, with the result that the capacity of the plant provided must be governed by the? amount of ore in sight at the time when mill construction is planned. This is immediately reflected in the cost per ton, there being relatively few tons over which to distributed the more or less static charges, such as hoisting, heating, supervision, administration, pre-production expenses, and other write-offs. (2) Development.-In mining this type of orebody, the main factor contributing to high costs is unquestionably the small tonnage of ore made available by a given amount of development. Thus, for example, from the data tabulated below it can be seen chat, assuming a 12-in. vein and a drifting cost of $9.00 per foot, the development charge for this item alone would be 71 cents per ton. Add to this the charges for raising, cross-cutting, shaft-sinking, and pumping, besides charges arising from development in waste, and the figure will be very considerably higher than 71 cents.

Jan 1, 1941

By Eric Barnard, Andreas Nashitati, John Tero, Guy Deschênes, Setta Mbalamba, John Rajala

The Otjikoto Mine, owned at 90% by B2Gold Corporation, is located 300 km north of Namibia’s capital city of Windhoek. The reserves from the open pit mine, estimated at 25.9 million tons with an average grade of 1.28 g/t Au, contain gangue minerals, pyrite and pyrrhotite, and have an estimated 10 year mine life. The feasibility study included an optimisation of gold leaching using CSTR for the original design. The results of the test work were used to establish the design criteria. Gravity tails from three composites (drill cores), representing the major ore types, were used. The XR3 sample (gravity tails) contained 0.32 g/t Au, while the XR2 and XR1 gravity tails samples (used for variability) contained, respectively, 0.30 g/t Au, and 0.47 g/t Au. The optimum leaching conditions were: a pre-treatment of 7 h at pH 10.5 with 100 g/t lead nitrate, DO > 5 ppm followed by cyanidation at 300 ppm NaCN, pH 10.0, DO > 5 ppm for 48 h. The gold extraction was 91.5% (97.2% overall extraction gravity/leach) and the cyanide addition was 0.57 kg/t NaCN. Increasing the DO to 16 ppm did not show any economic benefits. No pre-treatment or a 4-h pre-treatment reduced the gold leaching kinetics. The XR2 and XR1 gravity tails samples had gold extractions of 92.9% and 92.3%, respectively. At the plant scale, an 11 h pre-treatment is used followed by 42 h cyanidation with 250 ppm NaCN and an average DO of 8 ppm and 230 g/t lead nitrate in 2016. The cyanide addition was 0.49 kg/t NaCN. The commercial operation started on February 28th, 2015. The overall gold recovery and production were 98.4% and 145,696 ounces for 2015 and 98.1% and 166,286 ounces for 2016. It was found that retention times, gold content of leach residues and cyanide addition are comparable for the lab and the plant. Details of the Otjikoto process flowsheet are discussed in this paper along with the results of the lab leach optimisation test program and the plant leach circuit performance and improvements.

Jan 1, 2017

By Alfred W. G. Wilson

THE state of development of its iron and steel industries serves as a 1eading index to the general condition of a nation's business affairs. In this paper, the authors present an economic study of the progress of this group of industries in Canada for the decade 1927-1936. The statistical data and most of the tables which accompany this article have been com-piled by John Casey, Statistician, Bureau of Mines; the text and some of the computations have been prepared by the seni0r author. The principal source of statistical information has been the publications of the Dominion Bureau of Statistics; where other sources have been consulted, they are noted in the text. All weights are given in short tons. Records for the years 1913 and 1918 are also presented in the group of tables dealing with iron ore and pig iron; they will serve as a basis for comparison with nearly normal years in the two decades prior to 1927-36, which included the abnorma1 years of the Great War. GENERAL REVIEW At the beginning of the decade under review, this group of industries had returned to almost normal production, as determined by pre-war conditions. Iron ore consumption showed a steady increase between 1927 and 1930; a marked decline began in 1930 and reached its culmination in 1932, when the recorded consumption of ore was 293,353 to11s, about 16 per cent of the average consumption during the first four years of the decade; the last four years of the decade show a gradual increase in consumption; the amount of ore used in 1936 was still slightly below the amount used ten years before, in 1927 (see Table 1, top).

Jan 1, 1938

By Grant J. Goddard

"The Iron Ore Company of Canada (IOC) has been in operation for over 30 years. Today, and in the future, technology and its application will play an ever more critical role in the company’s business success.The Carol Mining and Concentrating (CMC) division of IOC is energetically applying technology today to enhance performance and results, and is aggressively exploring opportunities to apply technology to support improved business results in the future.A critical area of focus is the application of technology to maintenance management performance. CMC has taken a “back to basics” approach to the fundamentals of maintenance management in 1995 and 1996. In parallel, the mine is aggressively implementing its Vision 2000 maintenance integration plan. This plan is targeted at levering the energies applied to sound maintenance management fundamentals as the company moves to a fully condition based maintenance approach.This paper discusses some of the strategies, key technologies and objectives of theVision 2000 maintenance integration plan at the mining operations of IOC."

Jan 1, 1996

By S. G. Luckey, N. R. Harrison, F. Nadeau, U. Brüx

"The adoption of tailored-rolled or tailor-welded blanks (i.e. TRB/TWB) in the automotive industry has been known to offer great potential for the optimization of weight, function, cost and complexity. Vehicle light weighting can further be achieved by using high strength aluminum alloys like the 7xxx-series. 7xxx-series alloys are capable of delivering specific strengths equal to or greater than high strength steels. However, room temperature formability of this aluminum class is limited, so one approach to forming 7xxx-series alloys is by hot stamping. Hot stamping utilizes an elevated temperature blank and the high pressure stamping contact of the forming die to simultaneously quench and form the sheet. This paper explores the initial feasibility of tailored thickness material for body-in-white applications when processed under hot stamping conditions.INTRODUCTION Steel tailor-rolled blanks (TRB) or tailor-welded blanks (TWB) have been used within the automotive industry as a method of reducing weight, expanding material utilization, and decreasing overall part/assembly cost (Ganeasan et al., 2015; Merklein et al., 2014; Hirt et al., 2005; Kridli et al., 2000). The production of such tailored thickness materials has resulted in over $2.5 billion (2016) in combined industry sales (Mubea, 2018). As automakers begin to adopt the manufacturing practices traditionally reserved for steel such as tailor rolling/welding with greater enthusiasm for vehicle light weighting, there exist an opportunity to expand the material database to extend beyond the traditional aluminum alloys found in current production. High strength aluminum alloys, i.e. 7xxx-series, are ideal for structural automotive applications due to their high specific strength; however, they have limited room temperature formability. Hot stamping, another manufacturing practice used by the steel industry, can be used to form these high strength materials. The combination of tailoring the thickness of a sheet material and hot stamping provides an opportunity for significant weight saving within an existing manufacturing footprint. This paper explores the potential and challenges of this approach when applied to structural body-in-white components. The methods for tailor rolling, tailor welding and hot stamping are described and applied to the production of a 7075 aluminum alloy B-pillar. The results are discussed in terms of feasibility and weight savings."

Jan 1, 2018

By M. Turek

Cost management in the conditions of increasing competition and unforeseen market turbulence constitutes one of the key areas of the enterprise?s activity. In the last two years the demand for hard coal on the domestic and global market of non-renewable resources has increased significantly. Polish hard coal mining industry, as an industry in the stage of decline, received a chance for rejuvenation. However, one of the most significant conditions of seizing this opportunity is the rationalization of mining costs and improvement of production effectiveness. Due to the significance of this issue, the main objective of the paper is to identify the possibilities of improving the production effectiveness in the hard coal mining industry. In order to meet such an objective, in the first part of the paper we measured effectiveness in the Polish hard coal mines in years 2006- 2011. The research encompassed three out of five mining enterprises operating in the country. Then based on the received results, guidelines concerning the improvement of effectiveness of production were created, taking into consideration infrastructural, technical, economic and organizational determinants. Furthermore, opportunities and threats for improving the production effectiveness, stemming from the external conditions have also been indicated.

Aug 1, 2013

By M. N. Pons, E. Benizri, B. Laubie, A. Bani, Université de Lorraine LRGP, P. Kidd, A. J. M. Baker

"Serpentine (i.e. ultramafic) outcrops in Europe cover more than 10,000 km2 and have a low-fertility and low-productivity, making them unattractive for traditional agriculture. In general, these areas are slowly abandoned by local farmers, affected by strong rural exodus and landscapes undergo a process of closure. However, ultramafic landscapes have the potential to provide multiple ecosystem services that can contribute to Europe’s goals towards insuring food security, production of renewable raw materials and renewable energy. Phytomining (agromining) aims at cultivating metal hyperaccumulator plants that are able to accumulate Ni and other strategic elements from metal-rich soils and transport them to the shoots (>1%), which can then be harvested as a bio-ore. Such metal-rich biomass can be used to recover highly valuable metals, e.g. nickel (Ni) and also to produce energy (heat, electricity). Nickel agromining can thus offer an eco-efficient alternative to classical pyro- or hydrometallurgical processes without disturbing the soil cover and the geology from soils and rocks that would be considered as low grade ores or sterile material for conventional mining methods.Phytomining agroecosystems can lead to better soil resource efficiency and can offer a fully integrated, new agromining agriculture that could cover thousands of km2 in Europe, benefit local communities with a sustainable rural development and provide a wide array of ecosystem services which will need to be optimised under a life cycle assessment methodology:1. Production of bio-sourced metal products2. Production of energy biomass3. Restoration of soil fertility for conventional agriculture (Ni stress)4. Limiting Ni intake by local populations and farmers5. Use and conservation of local biodiversity (plant and soil fauna and microflora) as cultivated ecosystems6. Store carbon in cultivated soils7. Enhance pollination activity at landscape level.Nickel agromining could therefore change the economical balance in historically-disadvantaged ultramaficregions of Europe"

Jan 1, 2016

By W. J. Bennett

WHEN Dr. Horace Fraser, your President, invited me to speak to you today I advised him in confidence that I was leaving my present positions on April 30th. In the circumstances it seemed to me that this audience might prefer to have as its speaker one who wo.uld J1ave a continuing association with the atomic energy programme. Dr. Fraser was kind enough to suggest that my re-marks might he of special interest to you, since I would be able to sum up my views on the atomic energy programme. I hope that I will not disappoint him or you on that score. I am particularly pleased that my last public appearance in my present positions should be at the Annual Convention of the C.I.M. since, as all of you know, a very important part of my work has been in the mining field. As it happens, my first public address on the subject of atomic energy and its raw material -uranium -was made at your Annual Convention in Montreal in April, 1949. It seems fitting that my final address should also be made at this convention -nine years later.

Jan 1, 1958