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By A. G. B. Hayes, C. L. Renzoni

"AbstractThis paper provides a rough outline of economic expectations for the near future and then goes on to discuss their effect on the expected demand for metals, using zinc, copper, nickel and aluminum as detailed examples.IntroductionMINING, as you are all painfully aware, is a cyclical business. We believe that it will remain so as long as there are economic cycles.The fortunes of the industry are tied to those sectors of the economy where decisions can be postponed until more favourable times: automobiles, housing, appliances, inventory building and capital spending. Over the past two years, while U.S. GNP fell by 3.8%, automobile production declined by 31 %, from 9.7 million units in 1973 to 6.7 million in 1975. Housing starts plummeted some 43% from 2.1 million units in 1973 to 1.2 million in 1975. Little wonder that U.S. copper consumption fell by 37% and zinc consumption by 38% over the same period.With the rest of the world's economies moving in unison with that of the United States, it is also not surprising that times have been tough for mining.Arthur Burns, chairman of the U.S. Federal Reserve, contends that each recession sows the seeds of its own recovery. The worse the recession, the better the subsequent recovery. If this is true, then the lot of the mining industry should improve significantly over the next two to three years."

Jan 1, 1977

By Z. Luo, China University of Mining & Technology, C. Duan

"The magnetic separation removal rate of pyrite could be improved effectively by increasing the susceptibility of pyrite. The electromagnetic characteristics and absorption response performance of high-sulfur fine coal were studied in strengthening the susceptibility of pyrite. In the process of treating the sample through the microwave, electromagnetic energy could be converted into heat energy due to dielectric loss and magnetic loss. The RL(dB) was evaluate the performance of absorption response of coal. The microwave improved the susceptibility was in ultra-high frequency region, which is the most natural resonance. The absorption fine coal to microwave was strengthened and microwave energy was improved by adding the magnetite powder with double loss characteristics as the microwave absorber. The dielectric properties and permeability characteristics of the fine coal trend were investigated by maxing magnetite powder. The microwave absorption in different coal thickness was surveyed through the reflection of energy loss.INTRODUCTIONMicrowave desulfurization is one of the most important research directions (Haque, 1999; Makul, Rattanadecho, & Agrawal, 2014; Su, Tang, Zhang, Jing, & Bai, 2014). The working principle of microwave absorption response can be briefly described as the interaction of the sample with microwave energy, which will result in the microwave energy converting into heat energy loss (Keangin & Rattanadecho, 2013). For specific samples, the polarization effect includes multiple polarization mechanisms(Meikap, Purohit, & Mahadevan, 2005). Different polarization mechanisms have different occurrence time and dominant mechanisms. Meantime, energy consumption will be occurred during the process of polarization effect (Chelgani & Jorjani, 2011; Rowson & Rice, 1990) . The absorption of microwave energy in the fine coal is a process of electromagnetic response (Znamenácková, Lovás, Mockovciaková, Jakabský, & Briancin, 2005). Microwave transfers the electromagnetic waves into the heat energy by microwave dielectric loss and magnetic loss for achieving the absorption of microwave energy in the treatment of samples (Lee, Kim, Kim, Chung, & Kim, 2004). The additive magnetic medium is Fe3O4 belonging to microwave energy absorber of double loss medium (Uslu, Atalay, & Arol, 2003)."

Jan 1, 2016

By G. E. Veins

This paper summarizes an investigation in which beneficiated ilmenite ore was smelted in a continuous, three-phase, 250 kv.a., open-top electric furnace. Minus %. inch ore was smelted, using the standard method. Fine ore, in the order of minus 14 mesh, was smelted in the briquetted form by the open bath method, and in the unagglomerated form by the cold dry-top method. The latter was shown to be superior. The data obtained .are discussed at some length. During the investigation, slag aver-aging 82.5 per cent Ti02 was produced over a period of 87 hours, the maximum being 85 per cent. Such slag should .be particularly attractive for the production of titanium tetrachloride, from which titaniurn metal is produced. The advantages of using paper-mill bark for producing a furnace charge of low bulk density, as required in cold dry-top smelting, were emphasized.

Jan 1, 1957

By M. Dupuis

It has been previously demonstrated [l] that there is no obvious thermal balance related issue limiting the size of a Hall-Héroult cell. Yet, it is well known that a forced-air sidewall cooling system is part of the AP50 cell design [2], In the present study, the authors analyze the impact of thermal loading on the mechanical deformation of high amperage cell potshells. The effect of adding cooling fins or a forced-air sidewall cooling system is then assessed.

Jan 1, 2005

By M. Girard, C. Farsangi, N. Singh

"Canadian Royalties Inc. owns and exploits the Nunavik Nickel Project: a copper and nickel deposit in Nunavik, Québec. The nickel and copper concentrates are filtered by plate and frame filter presses, and are transported 100km north to Deception Bay by truck. As the site is situated in the far north, extreme weather can be detrimental to production: roads can close for significant periods of time, resulting in the concentrator using all its storage capacity. During the winter of 2017, this accounted for over 100 hours of unplanned mill downtime. Different solutions to this problem were evaluated and the most economically viable combination of solutions was determined to be the use of concentrate storage containers and upgrading the plate size of the existing nickel filter press. By satisfying new, increased utility requirements, the cycle times would not change, but produce 30% more filter cake. Simulations were developed to determine the number of concentrate containers needed in conjunction with the upgraded press to eliminate unplanned downtime due to road closures and secure production through the winter. This paper summarises these simulations, the commissioning and start-up of the upgraded filter press, container loading procedures, and how this was put together to achieve a record 2018 winter season with a 90 percent reduction in downtime. The payback period of the project was 4 months. A specialised side-tipping trailer emptied the containers during the fall of 2018.INTRODUCTION The Nunavik Nickel Project is a nickel/copper mining project located in Nunavik, Québec. The nickel and copper concentrates are stored in stock tanks after thickening and are then filtered by plate and frame filter presses at the concentrator before being transported 100km to the shipping port at Deception Bay by trucks. The region is prone to periods of extreme weather during the winter, with winds that can reach +100km/hr and blizzards that severely limit visibility. The roads to Deception Bay are often affected by this weather, causing closures that last an average of 18hrs and as long as 72hrs. Additionally, there is a 15% chance that road closures occur within 24hrs of the last event. This has been an issue for the concentrator team since start-up in 2013, causing unplanned mill downtime every winter (Table 1) due to filling concentrate storage capacity during prolonged closures of the roads to Deception Bay."

Jan 1, 2019

By Fred G. Hewett

The Cassiar orebody is located in a sill-like serpentinite body intrusive into the Devonian-Mississippian sedimentary rocks of northern British Columbia. Subsequent intrusion of the Cassiar batholith formed the McDame synclinorium and produced chrysotile asbestos. Present information indicates an orebody of approximately 16,277,000 tons amenable to open-pit mining, but continued diamond drilling will be needed to accurately define total tonnage and grade. A program has been developed at the mine to provide the required information on a daily basis, and work is continuing on more effective dollar-value prediction methods.

Jan 1, 1978

By Leon J. Perrier

The paper describes the equipment in use, haulage grades, road conditions, tire sizes, tire performance and related problems. Various types of failures and causes, corrective action taken, tire records and reporting for control are also discussed.

Jan 1, 1977

By Cummings. J. B., R. Haworth

"THE OPERATION of the Potash Company of America, Ltd., at its plant near Saskatoon, Saskatchewan, is the result of many years of exploratory and development work, culminating in the construction of a shaft, milling, concentrating and other facilities necessary to the production of potash in a marketable form.The possibility that potash existed in •commercial quantities in Saskatchewan was first indicated in 1943, although it was not until mid-1946, when Bata Petroleums penetrated a potash bed at its Verbata No. 2 well near Unity that substantial in-ter.est was developed in the possible exploitation of this important mineral product.The Potash Company of America, which is the largest producer of pot-ash in the Carlsbad, New Mexico area, a district that has been sup-plying about 90 per cent of the North American potash demand, be-came interested in the Saskatchewan deposits •at an early stage. Its engineers made an intensive study of the western Saskatchewan area in 1947 and continued their review of operating problems throughout the next three years.""Potash"" is the commonly used general term applied to the minerals of potassium, of which there are several. The most common mineral forms in which it is produced are potassium chloride and potassium sulphate. The potash content of potassium compounds is ordinarily ex-pressed in terms of potassium oxide (K20) equivalent."

Jan 1, 1960

By M. Sukhram, S. A. Argyropoulos

"In the aluminum and steel processing industries there is a need for velocity sensors to measure the flow characteristics of liquid metal. This paper will present a sensor and an inverse heat transfer technique to determine the direction of velocity in flowing liquid aluminum. Experimental research work with the sensor involving liquid aluminum was conducted, using the Revolving Liquid Metal Tank at the University of Toronto, which rotates 50 kg of liquid aluminum with velocities up to 0.35 m/s. Experimental data for various magnitude of velocity demonstrate that the sensor records different thermal profiles under different fluid flow conditions. Using the transient temperature information and the inverse technique, the direction of velocity of the molten aluminum flow field can be inferred. INTRODUCTIONOur research at the University of Toronto has focused on developing invasive sensors to determine the velocity of high temperature liquid metals. High temperature in this setting is defined at VALUES (in excess of 660 °C. The discussion which will persist in this manuscript involves detecting the direction of flow in liquid aluminum using an inverse heat transfer technique. We first reported on the sensor which is used in this article in the following two publications (Sukhram and Argyropoulos, 2011a; Sukhram and Argyropoulos, 2011b). The motivation to perform this research is due to the lack of sensors available to characterize the conditions within a high temperature liquid metal reactor/vessel. A report conducted by The Minerals Metals and Materials Society (TMS Energy 2011) has suggested that the introduction of sensors into molten metal processing environments has the potential to increase process efficiency up to 15%. Such sensors will aid in the understanding of high temperature liquid metal processing operations with the goal to implement more efficient process design and practice."

Jan 1, 2012

By G. H. Agnew

When water floods are initiated after gas-oil ratios have increased, the transition period from the start of injection until" the gas-oil ratios are returned to the solution gas-oil ratio may be important for either economic or technical reasons. The transition period is longest, and consequently most critical in water floods where injection is equal to withdrawals. This paper describes a theoretical basis for predicting the behavior of such a system and outlines a procedure for making the necessary calculations. The calculation procedure is illustrated for two actual cases: a line drive water flood and a five spot water flood. In each case there is a reasonable similarity between the actual and calculated performance.

Jan 1, 1960

ONE of the morning sessions at the recent Annual Meeting was devoted to a Symposium on ways and means to expedite geological investigation, and also to promote greater prospecting activity, in Canada. It will be recalled that at the 1940 Annual Meeting, held in Winnipeg, a paper(l) prepared by Dr. G. A. Young, Chief Geologist of the Geological Survey, was presented, and was followed by a Symposium on Geological Investigations in Canada(2). On that occasion, the participants were in the main geologists, and they included the directors or other officials of each of the Provincial departments or bureaus of mines. At the Montreal meeting, the subject was discussed mainly from the point of view of the mining industry. The following pages present, in somewhat summarized form, the several contributions to that discussion.-ED. DR. J. J. O'NEILL(3), who was to have opened the Symposium, was unfortunately prevented through illness from attending the meeting. He had intended outlining the main features of his paper on The Exploitation and Conservation of Mineral Resources in a Balanced Development of Canada, presented at the last annual meeting of the Royal Society of Canada( 4). In his absence, DR.J. A. DRESSER presented a summary of the paper.

Jan 1, 1941

By E. Gaucher, M. St-Amant

"Among the electromagnetic surveys performed by SOQUEM in the last three years, a certain number of the more instructive cases have been chosen to illustrate the theory of electromagnetism by field examples of: (a) The depth penetration of the TURAM as compared to the SLINGRAM (Ronka) method. (b) The limitations of the TURAM as compared to the SLINGRAM method when a conductor dips the wrong way, or when it is small in size. (c) The expression of a shallow-dipping conductor in a SLINGRAM survey. (d) The effect on the SLINGRAM survey of deep ditches or reef structures.(e) A comparison between the CRONE and the SLING-RAM method in the Abitibi clay belt, by means of field and model studies, indicating a usually better signal-to-noise ratio for the SLINGRAM method. From the above and from other experiments, different electromagnetic methods are now being used by SOQUEM, depending on field conditions."

Jan 1, 1970

By K. H. Concannon, K. I. Hindle

"The use of simulation modeling in the primary metals industry (including mining, smelting, and metals processing) is expanding as significant cost-benefits can be realized by companies employing capital intensive processes. The economic scale and complexity of operations found in this industry is well-suited to applications using this ""what-if' computer modeling technique, ranging from proof-of-concept projects to testing facility design or configuration, and determining resource requirements. More recently this technique is being used to support on-going planning and scheduling for operations using the simulation as the engine to derive the best schedule. With increased computer processing capability, deterministic models are now being developed to capture the workings of a production system or conversion process, allowing real-time monitoring and scheduling of these operations. This paper presents a sample of some recent discrete-event simulation modeling applications that demonstrate the capability and benefits of this technique in the primary metals industry. These include the use of simulation to support the long-range planning of underground mining operations; the modeling of a metals supply chain network that employs a multi-modal distribution system; the scheduling of a metals coil finishing process using a deterministic simulation model; and a more detailed description of the use of simulation to model furnace and converter aisle activities within a smelter operation in Northern Canada."

Jan 1, 2007

By J. Kouam

Al-Si-Cu and Al-Si-Mg alloys are widely used in several applications. Although they can be produced near-net-shapes, products made of these alloys very often require some machining. The purpose of this study is to evaluate the machinability of A319 and A356 under TO and T6 conditions. The machinability was assessed using during dry drilling machining process and the machinability indexes used are the chip form, the chip breakability and the cutting forces. It is found that 319 and 356 exhibit different machinability behaviors, especially in the T6-condition in terms of forces requirements, chip breakability and chip segmentation. It is also found that both the microstructure of the workpiece materials and the machining conditions significantly affect the chip formation mechanism, and therefore, the machining parameters could be selected to promote a chip form that is easily manageable in production.

Jan 1, 2011

By N. Bakhshizadeh

In this investigation, the aging effect on creep behavior of A12024-10%SiC composite fabricated by powder metallurgy was studied. P/M bars were manufactured by hot powder extrusion method at 450°C with a ratio of 16 to 1. Creep specimens were over-aged at 187 ºC for 43 h. It was found that almost full density composite with relatively homogenous distribution of reinforcing particles throughout the aluminum alloy matrix could be attained by direct powder extrusion process. Creep tests were conducted at temperatures from 275 to 325°C under stresses from 25 to 60 MPa. The analysis of the creep mechanism determined that dislocation glide was the predominant mechanism of plastic deformation. The activation energy of the creep process was found to be higher than that of lattice self-diffusion in pure aluminum.

Jan 1, 2007

By R. Burnette

Gold has been mined from a variety of deposit types that range in age from Archaean to Recent. The large variability in the geological settings of the gold deposits implies transport and concentration of gold by magnetic, hydrothermal and sedimentary processes. The factors that control the concentration of gold at certain sites and the grade estimation thereof remain major topics of debate. Due to the complex nature of the Witwatersrand Basin a mineralogical study, including mineralogical, petrographic and geochemical investigation was launched on TauTona Mine in order to characterize the various reef facies. The aim of the investigation was to determine if a correlation could be found between macroscopic characteristics of the reef, hanging wall and footwall, and the microscopic nature of the ore (especially gold grade). Petrograpgic and mineralogical results indicate that a correlation exist between gold, detrital and hydrothermal sulphides, uraninite, carbon, detrital heavyminerals and phyllosilicates. No correlation exist between gold and Mg, Fe or S. It appears that clast supported reef is of higher wade than matrix supported, but more work is suggested. No correlation exists between reef thickness and grade. The reef samples had the lowest phyllosilicate content compared to the hanging wall and footwall samples with pyrophyllite the most dominant. All of the correlations diagrams showed significant scatter and suggests a multi- factorial mineralization model. Gold distribution is also controlled by sedimentary features and thus it is not possible to select a single model for the formation and distribution of gold. It is evident that both sedimentary and hydrothermal factors influenced the mineralization and gold distribution on TauTona mine. It is thus essential that all related theories be incorporated in the development of a grade prediction model.

Jan 1, 2011

By Bruce W. Smith

Non-contacting, radioisotope density and level gauges are discussed. The characteristics of the more commonly used isotopes, the techniques of detection and the methods of presenting information are reviewed. The gauge parameters of accuracy, response time and long-term stability are tabulated with reference to calibration techniques and operating requirements. Automatic control systems, both pneumatic and electrical, are used in conjunction with density gauges on filter feeds, and in thickener underflow and heavy media processes. These systems are described. Procedures for installation, start-up and operator training are outlined, along with considerations of preventative maintenance and service requirements. Typical gauge system costs, including capital expenditure, installation, start-up and service, are presented, wherever possible, in order to provide a basis of comparison with more conventional systems.

Jan 1, 1964

By David Burchell

Duckbill mining is probably the simplest method of loading coal mechanically at the face in underground mines. It is a means of reducing the amount of physical labour required to produce a ton of coal. In effect, it is merely shaker conveyor mining brought up to date with the addition of a self-loading head or 'duckbill' on the end of the conveyor line. Any mechanical device used to load coal is a means of supplanting the human muscles as the medium for getting the coal off the floor into the transportation equipment. There can be no argument with the conclusion that a man can lift so much and no more. He can load more tons of coal on a low conveyor, because the lift is less, than he can in a pit car two, three, or even four feet high. Thus it follows that, if the lifting operation is entirely eliminated, the man should be able to produce even more coal. A mechanical operation is essentially a multiplication of physical strength. Although there are various ways in which coal can be loaded at the face by mechanical means, there is, perhaps, none more adaptable than shakers equipped with duckbills. This is particularly true for thin seams and in mines having heavy, tender top conditions which require close timbering. However, as we are discussing duckbill mining, we will make no further reference to any other type of equipment. The first, and to date the only, mine in eastern Canada to adopt a system of mechanical loading at the face is the Franklin mine of the Bras d'Or Coal Company, Ltd., at Bras d'Or, N.S. An experimental Goodman shaker conveyor with a self-loading head, or duckbill, was installed in this mine in 1940. Since that time other units have been placed in operation so that, today, this mine is completely mechanized. The method of operation 1s room-and-pillar. The operation is carried on in a 42-in. seam, which lies 420 feet beneath the Sydney Main or Harbour seam in the Sydney Mines basin. The slopes bear N.25 30'E., dip 10 per cent seaward, and are about 6,000 feet in length. The physical conditions of this seam do not make it particularly adaptable for complete mechanization as it contains a large amount of foreign material, such as clay intrusions or wash-outs and iron pyrites. These clay intrusions, known locally as 'troubles', vary in thickness from a few inches to as thick as eighteen feet and usually replace the coal to the full height of the seam.

Jan 1, 1947

By M. B. Mansur, A. S. Guimarães, A. J. M. Santanilla, D. C. R. Espinosa, J. A. S. Tenório, R. A. Pini

The separation of Ni and Co from sulphate medium containing Mn, Mg, Cu and Ca was carried out by solvent extraction. The object of this study was to investigate the synergistic effect using phosphinic acid (Cyanex 272) and carboxylic acid (Versatic 10) and their mixtures in kerosene. The extraction percent of each metal ion was found to increase with increasing pH and extractant concentration. Co was preferentially extracted over Ni under the same extraction conditions. The separation factors of Ni/Co increased with the use of the synergistic systems investigated.

Jan 1, 2014

By M. Abumiya, N. Onodera

"The synthesis of large scorodite particles in non-ferrous metallurgical industries usually requires a high-cost operation involving heating and high-pressure autoclaving. To overcome these obstacles, an atmospheric-pressure process for scorodite synthesis (DMSP®) was developed, in which ferrous ions were oxidized by oxygen gas in the presence of pentavalent arsenic ions. This process gives scorodite of good crystallinity with particle sizes as large as 15-20 µm. The solutions used for scorodite synthesis in the DMSP® are prepared from various residues containing arsenic from non-ferrous smelters. The solutions may be contaminated with Cu, Sb, and Bi, for example, and therefore the effects of such impurities on the formation of crystalline scorodite need to be investigated. In this study, the effects of Cu, Sb, and Bi contaminants on the formation behaviors of scorodite particles in the DMSP® were investigated systematically.INTRODUCTIONThe synthesis of crystalline scorodite (FeAsO4·2H2O) is a suitable method for arsenic (As) stabilization and storage of As-containing by-products such as flue gas dusts in non-ferrous smelters. It is expected that the formation of large, highly-crystalline scorodite particles would be an ideal method for avoiding the release of arsenic to the environment. Generally, autoclave methods under pressurized oxidation conditions at temperatures above 100°C have been used for the formation of arsenic minerals such as scorodite. However, the autoclave method requires sealed vessels that are resistant to high pressure, heat and acids. This process is also unfavorable on account of the high construction expenses, and high running costs as a result of vapor heat loss. Processes for synthesizing scorodite under atmospheric conditions at temperatures below 100°C which do not need an autoclave have therefore been extensively investigated (Demopoulos, Droppert, & VanWeert, 1994; Demopoulos, 1996; Demopoulos, Lagno, Wang, & Singhania, 2003; Droppert, Demopoulos, & Harris, 1996; Filippou & Demopoulos, 1997).Recently, Fujita et al. (Fujita, Taguchi, Abumiya, Matsumoto, Shibata, & Nakamura, 2008a, 2008b, 2009; Fujita, Taguchi, Kubo, Shibata, & Nakamura, 2009; Fujita, Taguchi, Shibata, & Nakamura, 2009) developed a new method for producing large scorodite crystalline particles with improved filtration and washability properties at normal atmospheric pressure and temperatures below 100°C. In the new method, oxygen gas (O2) is blown into solutions containing a high concentration of arsenic ions (As(V)) and ferrous ions (Fe(II)). The Fe(II) ions were subsequently oxidized to ferric ions (Fe(III)), resulting in the formation of large scorodite particles. High supersaturation of solutes such as Fe(III) will result in excessive nucleation, and the formation of poorly crystalline phases. The scorodite formation must therefore be conducted in a manner that avoids the critical supersaturation level being exceeded. It is supposed that the oxidation of Fe(II) to Fe(III) by O2 gas in the new method suppressed the supersaturation of Fe(III) during scorodite formation. The low Fe(III) supersaturation resulted in formations of highly crystalline scorodite particles of size of around 20 µm. In June 2008, based on the developed process described above, DOWA began experiments to verify the industrial capability of a plant with a capacity of 30 MT/month of As. It was successfully proven that it is possible to produce crystalline scorodite industrially on a commercial scale. This process was named and trademarked as DMSP® (Kubo, Abumiya, & Matsumoto, 2010)."

Jan 1, 2012