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By Y. Héroux, A. Chagnon, M. M. Savard

"Résumé- Le gîte de Pb-Zn de Gays River s'accompagne d'anomalies des propriétés de la matière organique (MO) et des assemblages de minéraux d'argile (AMA). L'association entre la minéralisation, la distribution de la réflectance de la MO et des AMA suggère que ces traceurs peuvent servir à l'exploration des sulfures de métaux de base dans cette région.A l'emplacement du gîte, la réflectance varie considérablement (0,80% à 1,88%), pouvant même afficher une baisse avec l'enfouissement, ce qui est interprété comme une altération chimique de la MO. Les valeurs les plus élevées s'accompagnent localement de quelques textures en mosaïque et délimitent une anomalie thermique au centre sud de la région. Parmi les minéraux des argiles identifiés, l'illite et la chlorite sont terrigènes alors que la smectite, la kaolinite et la corrensite sont authigènes et, à l'instar de l'altération de la MO, résultent des nouveaux équilibres chimiques créés suite à la précipitation des sulfures.Abstract- The Gays River Pb-Zn ore deposit is associated with anomalies defined from the characters of the organic matter (OM) and from the clay minerals assemblages. The relationships be­ tween these anomalies and the mineralization at the mine suggest that these parameters can be used as new guides for the exploration for base-metal sulfides in this area.The vitrinite reflectance (RJ shows a wide range of values (0.8% to 1.88%) and exhibits an anomalous suppressive effect with depth of burial at the mine site, suggesting a chemical alteration of the OM. The highest R, values are associated with mosaic textures and outline a thermal anomaly at the south-center of the studied area. Among the identified clay minerals, illite and chlorite are terrigenous, whereas smectite, kaolinite and corrensite are authigenous and, like the alteration of the OM, are due to the new chemical equilibria resulting from the precipitation of the sulfides."

Jan 1, 1994

By W R. Honeywell

Two series of laboratory flotation tests were carried out to study the treatment of Faraday ore by two-stage flotation. First the acid-consumers and then the uranium minerals were floated. On ore ground in the Faraday mill grinding circuit, and using Faraday mill water in the flotation step, a recovery in the flotation concentrate of from 91 to 93 percent of the uranium was obtained in 45 to 50 per cent of the weight at a grade of 0.24 per cent U30s. The saving of acid in leaching the uranium-bearing flotation concentrate, as compared to leaching the whole ore, ranged from 30 to 46 per cent. The average over-all extraction resulting from flotation and leaching of the flotation concentrate was 88.1 per cent. The best collector for the acid-consumers was sodium oleate. Acintol F A-1 emulsion was the best collector for the uranium minerals, and, in the uranium flotation step, an acid pH in the slurry was found to be necessary. The reagent costs were estimated to be 22 to 26 cents per ton of ore.

Jan 1, 1963

By H. Saari, D. Y. Seo, J. Beddoes, T. R. Bieler

Prior work on effects of lamellar orientation on creep rates and other mechanical properties have shown that having lamellae parallel to the tensile axis provides optimal creep resistance and good strength. Consequently, a directional solidification system was used to examine the effect of solidification rate on the development of crystals with lamellae parallel to the growth direction. The nominal chemical composition of TiAl ingots was Ti-46A1-2Mo-2Nb (at%) and the ingots were 20 mm in diameter and 180 mm long. The master alloy bars were placed in a high purity yttria mold on a copper chill plate and raised into the hot zone of a Bridgman furnace. The alloys were melted and then directionally solidified at withdrawal rates of 4, 8, and 12 mm/min. As-cast specimens were sectioned at positions of 4, 22, 66, 111, and 155 mm from the bottom of the ingot to evaluate microstructure and crystallographic texture as a function of distance from the bottom of the ingot. The directionally solidified microstructure consists of continuous columnar grains with fully lamellar structure, a network morphology of primary 13, yttria particles, and interlocked columnar boundaries. For all three ingots, the texture at 4 mm shows many peaks, with isolated strong peaks, and a slight tendency toward <111> plane normals within about 20° of the cylindrical axis. At 155 mm, all specimens showed substantially stronger clustering of <111> orientations near the cylinder axis, with the strongest clustering of poles occurring for the 8 and 12 mm/min specimens. Analysis of diffraction peaks indicates that strongly compressive residual stresses in the radial direction are present in the casting. The combined microscopy and texture analysis provides more complete understanding of the processes of directional solidification of TiAl alloys.

Jan 1, 2004

By David Forrester

"At the 95th CIM Annual General Meeting in Calgary, 1993, a paper entitled “Progress on Futuristic Mining Technologies” was presented(Matthews and Sarin), in which they outlined the goal of continuous excavation of hard rock and some of the technologies being developed to achieve it. The subject continues to be featured in periodic reviews and articles in the literature, (Gertsch, 1994; E&MJ, 1995). Matthews and Sarin note the considerable success of the development and application of continuous mining technologies in the soft rock under-ground mining industry, especially those in coal and potash, with major benefit to overall production, productivity and economic viability. It is the belief that similar achievements can be realised in the underground hard rock mining which continues to drive the development of hardrock continuous mining technology.This overview has been prepared specifically for this issue of the CIM Bulletin. It attempts to tie together current advancements in continuous mining in soft rock (where remote control and automation are already well established) with the background and status of development in hard rock continuous mining. Following a brief review of key factors and machine types, soft rock aspects are discussed, then a more detailed review is given of hard rock technology, with particular reference to Canada’s HRDK Mining Research Ltd. and their key role.The mining industry has long been at the forefront of technology development, for example, the application of the early steam engine to reach reserves at greater depth for dewatering mines in the industrial revolution. By necessity, the individual characteristics of seams and orebodies dictate the mining method, continually presenting mining engineers with new challenges. One of these is the extraction process itself and the goal of replacement of the drill-blast-muck cycle by continuous excavation. Very soft rocks have always been mineable using some form of cutting, even with primative tools. However, as the challenge has been taken up, technologies have evolved to steadily increase the hardness of rock that can be mechanically excavated. It may surprise some readers that at least three machines have successfully cut and loaded rock with an unconfined compressive strength (UCS) of 250 Mpa to 300 MPa (36 000 to 43 500 psi) in field trials (Table 1)."

Jan 1, 1996

By J. R. Goode

Rare earth elements (REE) and their compounds are critical ingredients in numerous necessities of modern life including: the permanent magnets used in electric motors, generators, speaker and hard drives; high performance automobile tires; catalysts; phosphors; optical glass; etc. World production of REE in 2014 was about 110,000 t with about 98,000 t/a being “Light” (LREE) and the balance “Heavy” (HREE). Unlike other mined commodities, the majority of the LREE produced in the world is a by-product and that from a single iron ore mine in China. The balance of the LREE production comes from four REE-only mines, two in China, one in Australia and one in the USA (now on Care and Maintenance basis). The LREE operations comprise very unusual flotation processes and complex hydrometallurgical plants. In contrast, most of the HREE come from a multitude of small in-situ leach operations exploiting a single, dispersed deposit in China using hydrometallurgy alone. All of the current REE operations produce an intermediate mixed REE product that must be separated to yield the high purity, individual, REE required by the market. This paper describes the processes being used to produce LREE and HREE intermediate products and the separation plants used to make the high purity REE compounds that are key ingredients in the magnets in earbuds, turbines, and automobiles; catalysts used in the production of gasoline, and so on.

Jan 1, 2016

By Ross Byron, Ken Roberts

"During the fall of 2001 a program was initiated to determine the feasibility of improving the metallurgy in the flotation circuit at the Penhorwood Talc Concentrator located near Timmins, Ontario. Bench scale testwork led Plant staff to believe that opportunities existed to improve the flotation performance. Pilot scale testing was then conducted using two vendors and their respective cylindrical type flotation cells to indicate where these opportunities existed.The results of the test program determined that the replacement of the existing flotation circuit (roughers, scavengers and cleaners) with new flotation cells could be economically viable. Justification was due to a reduction in installed horsepower, maintenance costs and a subsequent increase in recovery and throughput while maintaining product quality. Unforeseen benefits included reagent and air reduction, accurate level control as well as improved working conditions due to the removal of the antiquated equipment and ancillaries.This paper will detail the justification, installation and implementation of the new flotation circuit. A special emphasis will explain the hurdles encountered while trying to install and commission the circuit in an operating Concentrator with minimal interruptions to production.INTRODUCTIONThe Penhorwood mine and Concentrator is 28 yrs old and has gone through many ups and downs with different owners, Johns Manville, Steetley Talc and now Luzenac. It has also been expanded twice, with flotation and grinding capacity being added in recent years.All of the concentration is completed at the mine site while the fine grinding takes place in the Timmins micronizing plant.Luzenac’s Philosophy is to be the world leader in Talc production, technology and sales, having about 70% of the current world High Grade talc market."

Jan 1, 2004

By E. M. Watkin

"Land directly disturbed by hard rock mining activities in Ontario and Quebec was surveyed in 1974 as part of a country-wide assessment, (Murray 1977). Some 15, 000 hectares, or 5 7 square miles, are listed as having been disturbed by overburden removal, waste rock and tailings deposition (Table 1) in the region. That area represents sixty-eight per cent of the total area which ha1; been disturbed by mining in central and Atlantic Canada. Assessment of disturbed areas was undertaken using LANDSAT-1 and LANDSAT-2 satellite imagery. Certain limitations of the technique were recognized but the data obtained were considered a relatively acceptable assessment of the extent of disturbed areas larger than ten hectares.Approximately ten per cent of the land disturbed by mining in the two provinces has been reclaimed to varying degrees. Indeed, this proportion is correct for the country as a whole. As pointed out by Ripley, Redmann and Maxwell (1978), some of the land was disturbed long before environmental concern 01· reclamation were ever considered. In numerous instances reclamation will remain impossible until presently active operations are closed. Nevertheless, these authors feel such figures make it clear that reclamation has not been a high priority in Canada in the past. Canada is a vast country, and there has been little pressure toward efficient use of all land space. Most mining operations occur in areas distant from the country's population centres. Under these circumstances, therefore, the pressure to reduce the environmental impact of mining is much less than in the more densely populated areas of Europe and the eastern United States, where such activity can occur in or adjacent to large metropolitan areas."

Jan 1, 1980

By 13409, B. Arjang

"Ground stresses are one of the significant factors in the context of rockbursts and underground instability at some hard rock mines in Canada. Overcoring strain relief measurements using triaxial strain cells were performed at several mine sites to provide stress data for stability evaluations and mine design. Pre-mining stress determinations carried out at depths between 60 m to 1890 m resulted in the following average stress gradients:Maximum horizontal stress, s Hmax = 8.18 + 0.0422 MPa/m depthMinimum horizontal stress, s Hmin = 3.64 + 0.0276 MPa/m depthAverage horizontal stress, s Ha = 5.91 + 0.0349 MPa/m depthVertical stress, a; = 0.0266 ± 0.008 MPa/m depthThe maximum and minimum horizontal compressive stresses, with an average ratio of J.75 ± 0.45, prevail in east-west and northerly directions, respectively. Horizontal compressive stresses in excess of vertical overburden load were determined, indicating large variations in ratios to a depth of about 1000 m with decreasing trend toward depth.From present data, a particular regional zoning for the magnitude and direction of horizontal stress fields cannot be outlined.A common feature at mines with near vertical orebodies is that the maximum horizontal stress acts perpendicular to strike while the minimum horizontal stress is aligned on-strike. The vertical stress components approach the gravitational overburden load."

Jan 1, 1991

By W. Curlook

"A review is presented of a growing number of imperatives, some self-imposed, some imposed by society, which the mining and metals industry faces in carrying out its business. These imperatives bear on all activities from the exploration phase, through engineering, design, plant construction and operation, to decommissioning.IntroductionThe mining and metals industry must learn to cope with, i.e. manage, a growing number of imperatives. Some of these, such as the need for responsible stewardship of natural resources, the requirement to respect laws and regulations, the need to provide for safe and healthy workplaces, and the need to provide appropriate returns to investors of capital , have been with the industry for a long time (fable I). But the industry now faces additional imperatives that are growing in number and in importance (fable 2):• There is the growing concern about the impact of operations, not only on the workplace environment and the external environment, but also on the need to monitor not only the chemical concentrations in various effluents but to also monitor the effects of such emissions on the environment; i.e. there is a growing concern about the ""net"" consequences of operations.• There is the need for on-going improvement in productivity and safety to compete and survive in a global economy. The global business environment has become paramount.• There is the imperative to failsafe all designs, equipment and operational procedures, and having done that to provide for containment of unavoidable spills, and to have ready and in place systems for emergency response.• There is the need, indeed the imperative, to involve all employees in various quality improvement programs.• There is the imperative to face up to ""virtual elimination/zero emissions""; and• One must have waste management plans in place to cope with the need to reduce, reuse, and recycle; and• There is the need for decommissioning plans for all operations, for the restoration of business habitats to their original states (or better). Indeed, one must engage in the decommissioning exercise from day one, i.e. right from the time of design and commissioning."

Jan 1, 1992

By J. Budac, R. Kofluk, S. Mankasingh

Stainless steels such as 316L or 304 are normally relatively resistant to attack by nitric acid. However research at Sherritt International’s Fort Saskatchewan Operation reveals that when the stainless steel is immersed in an aqueous system in which nitric acid is used to dissolve metals such as cobalt or nickel, the steel can be seriously corroded. Sherritt is patenting a simple process for arresting the corrosion via the use of copper. This process is expected to substantially eliminate corrosion in processes where nitric acid is used to dissolve metals attached to a stainless steel substrate.

Jan 1, 2014

By J E. Gordon

For many years, it has been known that certain loud noises may, with prolonged exposure, temporarily or permanently damage a person&apos;s hearing ability. Pneumatic rock drills, al-though among the offenders, have, until recently, remained unaltered and unrestricted as to noise output. Now, there are drills available with higher rates of penetration and yet with noise levels reduced to those of previous models or less. Use of such drills, when proved to be superior in noise attenuation and of acceptable performance, should be encouraged in order to reduce future hearing losses to a minimum. People Have the Right to Hear P ERHAPS the earliest recognized indication of hearing loss due to industrial noise was the deaf-ness developed by the workmen in boiler factories. Here, the vibration set up in the shells by the riveting hammers gradually deteriorated the workmen&apos;s hearing, especially those whose job it was to hold the dollies inside the drum, where the sound is greatly intensified by reflection

Jan 1, 1963

By John A. Herbst, Xiangjun Qiu

"Prediction of wear on a microscale level in mineral processing equipment turns out to be a challenging undertaking. This is particularly true for cases in which the objective is to use such predictions for wear parts design. The key to obtaining such predictions has turned out to be the use of physics based models along with phenomenological constitutive equations. In this paper, two components of the HFS tool set, one for particles (DEM) and one for slurry (MPF), are used for modeling. These tools are applied to the simulation of wear of SAG/AG shell lifters/plates and wear in slurry pumps. In each case wear predictions are validated with plant measurements.INTRODUCTIONHigh Fidelity Simulation (HFS) has emerged as an important tool set for mineral processing plant equipment design and optimization (Herbst and Potapov, 2003; Herbst and Nordell, 2002; Herbst and Lichter, 2006). This tool set consists of Discrete Element Modeling (DEM) of particle motion, Multi-Phase Flow (MPF) for liquid motion, discrete grain breakage (DGB) for particle fragmentation and discrete grain liberation (DGL) for mineral liberation (Campbell, Potapov and Tsuji, 1997; Ferzinger and Peric, 1997; Potapov and Campbell, 1996; Herbst and Potapov, 2005).Three sample snapshots of basic HFS illustrating the use of each of the various types of mineral processing equipment are shown below.Figure 1 shows a snapshot of a DEM simulation of ball charge motion in a commercial scale Vertimill. DEM simulation involves simultaneous solution of Newton’s Laws of Motion for 400,000 balls."

Jan 1, 2007

By B. Misra, B. S: Sastry, Kollu S. Rao

"This paper reports the results of a finite element study of the geothermal heatflow into dry mine airways. For isotropic and unsteady state conditions the heatflow into mine airways is studied for a range of surface heat transfer coefficients between rock and air, and age of the airway. Dimensionless temperature gradient values are presented in tables for different values of Boit and Fourier numbers and the results are compared with Starfield tables and Gibson algorithm. It is found that Starfield tables have consistently over-predicted the G values with errors ranging from 2% to 10%. The differences between results obtained from the finite element study and the G values calculated from Gibson&apos;s approximation method are mapped. The small error values over a large range of Fourier and Biot numbers confirm the suitability of Gibson&apos;s algorithm to rapidly calculate G values for estimating the heat transfer from surrounding rock to mine air.IntroductionIn many underground mines heat is a major problem, and the provision of acceptable working conditions requires considerable expenditure on ventilation systems. The rational design and operation of these systems depend upon an understanding of the various sources of heat in the mine. The natural source, i.e. geothermal heat, contributes up to 80% of total heat added to mine air and it is difficult to analyze and predict the heat owing to a number of influencing variables. The problem of geothermal heat flow has been studied by many investigators (Goch, 1940; Starfield, 1966; Hemp, 1987; Amano et al., 1982; McPherson, 1986).The primary concern of this paper is to develop a better ready reference dimensionless transient temperature table for estimating heatflow at any stage of mine airway life."

Jan 1, 1994

Caterpillar Inc The world&apos;s largest manufacturer of construction and mining equipment, diesel and natural gas engines and industrial gas turbines. Technology leader in logistics, construction, transportation, mining, forestry, energy and electric power generation.

Aug 1, 2013

By Burns Sutherland

Although some mine hoisting systems incorporating steel wire ropes on drum hoists experience completely dependable performance on the hoist ropes for many years, other rope records illustrate an erratic behaviour pattern and, as such, become a source of concern to the operator. This paper describes the causes of the difficulties most commonly encountered and incorporates methods of providing preventative or corrective maintenance. When such a program is utilized wisely, within the allowable limits of shaft time available, it can be the means of avoiding many unforeseen circum-stances and of reducing operating costs, as well as rope costs, to a mini-mum.

Jan 1, 1970

By Leonard A. Wolff

"The 1980sfor the mining industry can be characterized as the survival of the fittest. High interest rates, low commodity prices, foreign subsidized competition and decreasing ore grades have contributed to a streamlining of the domestic mining industry in the United States, leading to the shutdown of operations or large cutback of work forces. The purpose of this paper is to look at the impact of a layoff on the employees of what was once a major uranium producer in south central Wyoming, twenty months after the final layoff and mine shutdown. INTRODUCTIONDecember 19, 1985, was the date of the final of three successive layoffs over a two-month period, leading to the complete shutdown of Petrotomics Company, a subsidiary of Getty Minerals Company. The final shutdown was due to a combination of depressed U3O8 prices and the takeover of Getty Oil Company by Texaco in January 1984.The layoffs affected 104 employees and included mine personnel, mill personnel and staff. Both hourly and salary workers were involved. The operation was considered non-union, however, a few mill hourly employees were unionized. At the completion of the layoffs. only a handful of employees remained for administrative and miscellaneous functions.For Getty employees, the terms of the merger agreement provided a generous level of separation benefits. The terms that were insisted upon by Mr. Petersen, Chairman of the Board for Getty Oil, stipulated that employees receive one month of severance pay, for each full calendar year of employment up to a maximum of two year&apos;s pay. This was the forerunner of what is now commonly known as the ""tin parachute”. All but the union employees of Petrotomics received these separation benefits. Union employees were covered by their separate, less generous, contract.Much of the literature that has been published in recent months has centred around the effects of layoffs on remaining employees, or the psychological effects on the severed employee. This study will emphasize the economic impact and ramifications due to a layoff, using the Petrotomics employees as a case example."

Jan 1, 1989

By Xing Jin, Dan Graffi, Glenn MacPherson, Dan Rioux

"The complexity of a modern flotation circuit makes it susceptible to disturbances such as changes in feed, ore mineralogy, equipment degradation, poor measurements and faulty instruments. Good measurements and a robust control system are critical to create and maintain a stable and optimum flotation process.This paper focuses on the development and implementation of process control applications in the flotation circuits at Xstrata Nickel’s Strathcona Mill ( referred to as the mill hereafter ) in Sudbury, Ontario. Following the path of ‘stabilize-improve-optimize’, basic controls to stabilize process variables such as flotation cell pulp level, air and reagent addition rates, cleaning-column feed and wash-water rates have been established. Factors such as best practice in pulp level and valve position measurement, feedforward control and the application of an appropriate control philosophy, have contributed to the significant reduction in process variability. For instance, standard deviation reduction of 79% for the Ni impurity in the column Cu concentrate grade was experienced and is shown. The variability reduction of the flotation circuits’ key process-variables paves the way to further improve and optimize flotation performance. A grams-per-metal unit reagent addition control scheme has been improved upon, particularly for different operating scenarios and better robustness. In addition, following significant stabilization of the primary controls and columns feedrates, Cu/Ni separation cleaning-column bias-control (cascaded to the wash-water rate) and hold-up control (cascaded to air flowrate) have been developed and tested. This strategy – from stabilization to optimization - is expected to achieve a more consistent control of final concentrate grades and improve recoveries.INTRODUCTIONFlotation is considered the most important and value-added process in the milling metallurgical plant and is still undergoing continuous evolution to treat greater tonnage and different ores (Wills, 2006). Starting over three decades ago, with the advent of on-line slurry content analysis devices, flotation automatic control has received persistent interest and a large number of applications have been reported (Thwaites, 1983, 1986 ; Mckee, 1991). Bergh and Yianatos (2011) reviewed different aspects of process control in flotation circuits and have evaluated the applicability of model predictive control to the process. Mckee (1991) analyzed the difficulty in developing lasting/robust process control applications for flotation circuits and stated that the path of stabilization-refinement-optimization would more likely lead to successful flotation circuit process control. Best practice on column process control was discussed by Bouchard, etc. where a multi-layered approach was proposed, provided that the measurement of column process variables ( i.e. bias, froth depth, hold-up, etc. ) are measured reliably (Bouchard & Thwaites, 2008). Wills (2006) stated that the best practice for flotation automatic control starts with fulfilling basic control objectives, such as stabilized flotation cell level, air flow, pH, reagent flow etc., before considering more advanced, or even optimal, control of metallurgical targets, which are more closely linked to economic performance."

Jan 1, 2013

By H. W. Parsons

Several low-temperature, dry chlorination processes for the treatment of sulphide minerals are reviewed, in a chronological order. These processes include the following: the Swinburne-Ashcroft, Baker-Burwell, Maim, Comstock-Wescott (Aldermac) and the Mitterburg Mining Process. Dry chlorination investigations at the Canadian Mines Branch (now CANMET) and the U.S. Bureau of Mines are discussed, as is a proposed process by the South Africa National Institute for Metallurgy. The techniques used in the process are discussed, as are the shortcomings, problems and failures of the methods.

Jan 1, 1978

By C. E. Ells

Current knowledge of the behaviour of inert gases in metals is reviewed, with particular emphasis given to the phenomenon of the growth of gas-filled bubbles.

Jan 1, 1960

By H. C. Gunnings, C. O. Swanson

"The Sullivan mine; at Kimberley in southeastern British Columbia; is the largest silver-lead-zinc mine in the Empire and one of the largest in the world.The original discovery was made in 1892 by four prospectors. Until 1899, when the branch line of the Canadian Pacific railway from Cranbrook to Kimberley was completed, little work was done on the property. In 1900, systematic development was started, and during the next 3 years 5,000 tons of ore was shipped to the smelters at Nelson and Trail. By 1903, some 300,000 tons of ore was developed, and a smelter was started at Marysville, about 5 miles from the mine. However, this smelter closed down in 1907 because of metallurgical difficulties after treating 75,000 tons, and the property came under the control of the American Smelting and Refining Company. An option on the property was taken in 1909 by the Consolidated Mining and Smelting Company of Canada, who exercised their option in the following year. During the next 5 years by selective mining and sorting 188,000 tons of high-grade ore was produced and shipped to Trail. This tonnage came from the upper levels, about 4,600 to 4,800 feet in elevation. At the same time, deep drilling down to the 3,900-foot level showed the presence of an immense body of complex ore. In 1915, the main adit-the 3,900-foot level-was started, and by 1919 this had been driven a distance of 2 miles to develop the ore above this level. Meanwhile, progress was being made in overcoming the milling problems. An interesting account of this work was written by the staff ( 4). In 1923, the first unit of the present concentrator was erected, with a capacity of 2,500 tons a day, and thereafter the rate of production increased rapidly. In 1934 it was around 8,000 tons a day, and to date a total of about 30,000,000 tons of ore has been sent to the mill. In recent years, a considerable part of the production has come from levels between the 3,900-and 3,350-foot, which were opened by an internal incline shaft started in, 1930. In 1942, tin was added to the products separated at the concentrator."

Jan 1, 1954