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By V. S. Sastri, Elboujdaini. M.

"Economics of wear in mining industry and methods by which wear cost may be reduced will be discussed.IntroductionCanada loses more than $5 billion annually due to friction and wear (Table 1). It is estimated that about $1.3 billion, or about 25% of the losses, could be saved through better application of existing technology (Table 2). It should be noted that the costs given in Table 1 and 2 refer to 1986. The losses due to friction and wear and the savings would be much higher in 1996. Tribology combines the many branches and specialties in science and technology concerned with understanding and combatting friction and wear. Specifically, tribology is concerned with the design and manufacture of sliding and rolling bearings, piston rings, gears, cutting tools and other devices in which surfaces interact, in sliding or other relative motion. Tribology is concerned with the correct use of materials for interacting solid surfaces, with the interaction of the surfaces with the lubricants, with the chemistry, physics and use of lubricants. It is concerned with the reduction of friction and wear and the avoidance of associated failures in machinery. Similar tribological components such as bearings are used in different technologies and similar tribological problems such as abrasive wear occur in different industries. Thus, tribology is in itself a generic science and technology, concerned with the generation and dissemination of knowledge on friction, wear and lubrication, and the application of the knowledge, to a wide range of industrial products and equipment, from ploughs to space equipment, from prosthesis to engines, from washing machines to railways, from computers to power stations, from paper mills to mines. Avoidable losses due to friction and"

Jan 1, 1997

By B. Surender Mohan

Mother Earth being a treasure of minerals, it is prime duty of the mankind to preserve this natural source to ensure steady growth of the nation. Utmost care is to be taken to see that these natural resources are explored and exploited scientifically in a sustained manner to ensure that the resource base improves and last longer. In this backdrop, the topic of ?Lignite - its resource and technology options to exploit deep seated deposits? is an apt subject to be deliberated upon in the present context, where the shallow deposits may slowly get dwindled. I shall deliberate upon the resource base of lignite, production profiles of the last five decades, consumption pattern, demand / supply projections, future available technology options to exploit the deep seated deposits, growth trends of the sector etc. in my paper. With the available resource base and future technology options, I can confidentially make a statement that ?lignite will remain as cocontributor along with coal to India?s energy generation and may well maintain its same status in the 21st century too, as it has been in the later part of the twentieth century?.

Aug 1, 2013

By M. Phylli Bray

"Concurrent with the continuing demise of many Canadian mining towns is the rise of a new method of providing remote mine sites with a workforce. This is the Long Distance Commute (LDC) which uses commuter labour and requires no permanent settlements to support the mine operation. It provides a flexible and cost effective method of operation to the industry and relieves both governments and industry of the expense of building and maintaining mining towns. However, little attention has been paid to the effect on workers or their families of the LDC work schedule whereby workers spend a fixed number of days at the site followed by a fixed number of days at home. Off-shore oil rig experience would indicate that negative social impacts may be expected. Research leading to an understanding of the problems involved seems to be indicated. One innovative suggestion has been to use already established but dying mining towns as workforce pick-up points for new LDC operations further north.BackgroundUntil recently, mine towns were considered as a necessary component of mine development. This was a natural symbiosis resulting from the need to provide workforce accommodation close to isolated mine sites. The early mine communities in Canada were often just a huddle of shacks around a head frame. Gradually mining companies began to provide housing which varied from basic duplexes and quads in grid pattern layout to professionally planned and designed towns, either model company towns or the more recent suburbs-in-the-bush, the so-called ""instant towns"" of the postWorld War II era of resource development. The improvement in accommodation reflected the need to attract a stable workforce as mine operations became more sophisticated. City amenities were expected and offered in these mine towns as a way of encouraging a permanent community of mining families. Indeed in towns like Manitouwdage, Schefferville, and others, it was not unusual to find a significant percentage of two- and three-generation families apparently providing the permanent mining communities so desired by mine operators."

Jan 1, 1991

By Jamel Sgaoula

During 1998 COGEMA Resources Inc. announced that operations at the Cluff Lake mine will be suspended indefinitely by the end of year 2000 as a result of deteriorating uranium market conditions. To remain profitable, Cluff Lake mine started an aggressive cost reduction program. A cost reduction team was formed to look for ways to lower production costs. The focus of this team was to screen all areas and to come up with ideas to improve the economy of the mine and ensure the viability of the operations over the remaining three years of operations. Among the areas where significant savings were achieved are: (1) replacement of portion of cement with fly ash in backfill; (2) backfill optimization; and (3) new shotcrete plant installation on site for bulk in-house shotcrete production. This paper details the research work carried out by Cluff Lake mine on these projects and results of its application.

May 1, 2001

By H. H. Gardner

INTRODUCTION THE problem of mechanization is one of the most vital in the minds of Alberta coal operators today. In these times of constantly increasing operating costs, any way of decreasing the cost of a ton of coal must be explored to the limit. There seems no better field for such effort than the successful application of power to the mining and loading of coal. We are fortunate in having neighbours to the south who have made .remarkable progress in recent times along these lines. Higher tonnages per man have resulted in higher wages to the employee and lower cost to the employer. It might seem that our problems could be solved merely by imitating our neighbours. Unfortunately, neither practice nor experience substantiate this conclusion. It is with the purpose of reviewing our accomplishments, as compared with practice in the United States, and at the request of the Prgoramme Committee for this meeting, that this paper is written. The Committee believes that such a general discussion and comparison may well lead to further advances in our mining methods. SUMMARY OF PRACTICE IN THE UNITED STATES A visit to the highly mechanized coal mines of the United States is always most instructive and encouraging.

Jan 1, 1951

By Bern Klein

Motivation for Improved Energy Efficiency in Mining ? Canada potentially adopting Greenhouse Gas Emissions and Intensity Legislation in 2013 ? BC -Climate Action Plan and Energy Conservation Agreement in 2008 ? BC Energy Plan 2007 -BC Hydro is mandated to save 50% of new load growth ? TSM Initiative -Energy Management, Energy Reporting, Setting Energy Targets, GHG Management BC MOU for Energy Conservation Agreement -MEMPR, MABC, BC Hydro

May 1, 2010

By D. F. Sangster

"Eight volcanogenic massive sulphide districts in Canada and Japan, ranging in age from Archean to Miocene, were selected for analysis. The study revealed that: {I) each district has an average diameter of 32 km; (2) the districts contain 4 to 20 deposits each, with an average of /2 deposits; (3) the average total base metal content per district is 4.6 million tonnes, with a coefficient of variation of32%; (4) ranked in order of size, the largest deposit in each district contains, on average, 67% of the total metal and the second largest about 13 %. The remaining deposits range downward in decreasing proportions. Empirical observations such as these may be used f or evaluating the undiscovered potential of new districts as well as contributing to a better understanding of the distribution and genesis of this important class of base metal deposits. Previous WorkThe characteristic geological features o f volcanogenic massive sulphide deposits have been described by numerous authors over the past fifteen years and it is now widely accepted that these deposits comprise a major ""deposit-type."" In addition to these geological parameters, however, it is now becoming apparent that volcanogenic massive sulphide deposits show several distinctive grade-tonnage relationships. For example, Singer et al. (1975) demonstrated a slight negative correlation between copper grade and ore tonnage in their sampling of 146 volcanogenic deposits. In a study of 110 Canadian Precambrian deposits of this type, Boldy (1977) showed that the size of the modal deposit is 0.39 million tons, that of the median deposit is 1.40 million tons and the arithmetic average is 6.85 million tons. Moreover, Boldy's data show that the average grade of combined base metals (Cu + Zn + Pb) for each of the se three deposit-sizes is, respectively, 6.25%, 5.35% and 6.47%. Because the lead content of Canadian Precambrian volcanogeni c deposits is most frequently less than 1%, the total metal grade is effectively Cu + Zn . From Figure 2 in Bold y (1977), it can be seen that 83% of the deposits fall in the range of 0.l to 10 million tons ."

Jan 1, 1980

RISKGATE is an interactive online risk management system developed by the Minerals Industry Safety and Health Centre (MISHC; University of Queensland) to assist the mining industry in implementing continual improvement in management of major unwanted events so maximising health and safety performance. A comprehensive body of knowledge has been compiled from diverse mining industry experts for risk management of tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives, manual tasks and slips/trips/falls. This paper presents an overview of the RISKGATE body of knowledge captured specifically for the management of unwanted events that stem from the handling and use of explosives (drill and blast) within surface coal mining operations. The knowledge presented is divided into a series of initiating events (listed below) within which there are further degrees of classification based on design, operation, and management concerns. Initiating events: ? Loss of control of explosives and associated chemicals in storage on site ? Loss of control of explosives and associated chemicals during transport ? Loss of control of explosives and associated chemicals during manufacture ? Loss of control of explosives and associated chemicals during handling and blast operations ? Loss of control of explosives and associated chemicals during disposal The system guides the user in generating substantive and leading-edge controls to assist in the design, management and reporting of drill and blast operations to meet stringent internal and external requirements. From a broader industry perspective, RISKGATE provides an environment for knowledge capture and knowledge exchange to drive innovation and best practice in the identification, assessment and management of risk. By capturing operational knowledge from industry experts, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover in the coal industry.

Aug 1, 2013

By J. A. Finch, G. Labonté

"A long-standing objective has been to obtain interpretable measurements of the oxidation-reduction potential in mineral slurries. For this purpose several sensing electrodes (black platinum wire, platinum foil and spiral, gold foil and spiral, and sulphide minerals such as chalcopyrite and galena) were investigated to determine their response to the presence of sulphide minerals in the pulp, and to the addition of reagents commonly used in flotation. The observed discrepancies between the electrodes may be explained using a combination of the classical mixed potential model for complex solutions and the probability of contact between the mineral particles and the sensing electrode. It is shown from laboratory testwork that gold spirals are preferred over platinum electrodes. Finally, some of the practical aspects of using the electrochemical measurements in a plant environment are discussed.IntroductonThe interpretation of flotation of sulphide minerals in terms of electrochemical (electron transfer) processes has brought new possibilities for process control of selective flotation. Investigations on massive and compacted particulate bed electrodes have shown that the flotation of a given mineral in the presence of a collector can be controlled by the potential induced on the mineral surface. Also, phenomena such as collector less (self-induced) flotation, activation by heavy metal ions, and natural selectivity sustained by galvanic coupling during flotation might also be controlled by electrochemical means.The technique for measuring electrochemical potential in slurries is an adaptation of that used for solutions. The measurement of the oxidation-reduction potential of a solution (ORP , Redox, Eh) is usually carried out by immersing a noble metal electrode (platinum, gold or silver) and a non-polarizable reference electrode: Standard Hydrogen Electrode (SHE), Standard Calomel Electrode (SCE), or silver/silver chloride (Ag/AgCl) in the solution. (The abbreviation Eh implies the SHE is the reference electrode.) The potential difference between the two electrodes is measured using a high impedance electrometer. ASTM standard D 1498-76 (revised 1981)(1) covers the practical details of such measurements; however, it does not deal with their meaning either in complex solutions or in mineral slurries ."

Jan 1, 1988

By D. G. Klaren, E. F. de Boer

Self-cleaning fluidized bed heat exchangers have demonstrated unparalleled performance internationally for the implementation of indirect heat transfer in severely fouling fluid environments. The ingenious configuration of recirculated cleaning particles through the tubes of vertical shell and tube heat exchangers provides the ability to solve any problems that arise as a consequence of tube-side fouling during indirect heat transfer to process fluids or slurries. In most cases, the cleaning particles consist of chopped metal wire, however other process-specific materials have been used. In addition to the mitigation of fouling effects, a number of other significant benefits for slurry heating are afforded by the mode of operation of the self-cleaning fluidized bed heat exchangers. Increased turbulence at the slurry/tube interface is imparted by the action of the fluidised particles, resulting in very high heat transfers at relatively low liquid velocities. Furthermore, given the thixotropic nature of most process slurries, the action of the fluidised particles imparts additional shear to the process slurry, resulting in shear thinning effects with a consequent reduction in pressure drop and enhancement of heat transfer across the heat exchanger. The benefits provided by the self-cleaning fluidized bed heat exchanger make it the ideal option for the indirect heating of laterite nickel slurry for High-Pressure-Acid-Leach (HPAL) plants. This article explains the principle and application of the self-cleaning fluidized bed heat exchanger technology for the processing of laterite nickel and cobalt slurries in HPAL plants. It also presents an elegant method to revamp existing direct heated laterite nickel and cobalt processing plants into an indirect heated configuration employing self-cleaning fluidized bed heat exchangers.

Jan 1, 2004

By C. Moreland

Fluidized low-temperature carbonization of coal, a recent development, offers a possibility of reducing fuel costs of coal-burning electric ?generating plants. The Research Council of Alberta have built a pilot plant and are conducting a programme to -develop a carbomzation plant for Alberta sub-bituminous coals which will produce char suitable for use as a .boiler fuel, and tar of a potentially high value as a ?chemical raw material. The economies of the process as a whole, and the value of the tar, have yet to be assessed.

Jan 1, 1958

By Barbara Hendrickson

Outline ? Canadian Regulatory Update ? Turning the Corner: Background & Status ? Implications of U.S. Waxman-Markey bill for Canada ? Federal-provincial considerations ? Current certainties and uncertainties ?Turning the Corner? as Originally Proposed ? April 26, 2007 - the Canadian federal government announced Turning the Corner: An Action Plan to Reduce Greenhouse Gases and Air Pollution (?Turning the Corner?)

May 1, 2009

By J. W. Sanger

The establishment of a central steam-heating system in Winnipeg and its inauguration in October, 1924, has attracted a considerable amount of attention. Not only does it excite the curiosity of the engineer, but it has stirred financial and civic bodies throughout Canada to such a degree that there is now a much keener general interest in this particular type of public utility than has been shown heretofore. This does not mean that we may expect a mushroom growth of central-heating systems in all our larger Canadian cities in the near future, but it does mean that the pioneer work which Winnipeg is now doing will undoubtedly be used to guide others in their judgment as to the feasibility of similar projects elsewhere. The success of the municipal hydro-electric system in Winnipeg, and the low rates for electricity resulting therefrom, was without a doubt the most important factor influencing the citizens of Winnipeg to venture into this new field. The events which led up to the central steam-heating proposal in Winnipeg are interesting.

Jan 1, 1926

By G. A. Bezuidenhout, J. Davis, S. M. Bradshaw, J. P. T. Kapusta, D. K. Chibwe

"This research work forms part of an assessment to complement the feasibility of implementing high pressure sonic injection into relatively small (2.25 m I.D by 3.66 m I.L) Peirce-Smith converters (PSC) used at Lonmin Plc. Work has been carried out to characterize the fluid dynamics of three-phase (air, matte and slag) fluid flow in these converters using Computational Fluid Dynamics (CFD) simulations. The investigation has been done to study the flow pattern of the three phase system at high air pressure injection achieving sonic velocity at the tuyere exit into the converter. The 2-D and 3-D simulations of the three phase system were carried out using the volume of fluid (VOF) and realizable k -e turbulence models to account for the multiphase and turbulence nature of the flow, respectively. These models were implemented using the commercial CFD numerical code FLUENT. A detailed study of the flow pattern has been presented in the form of contour plots and the results obtained are useful for understanding plume extension and velocity distribution, shear wall stress distribution, and phase distribution characteristics in the system. The results provide a basis for further development of sonic injection technology into relatively small industrial Peirce-Smith converters with the ultimate objective of achieving lower energy consumption, improved process efficiency and increased throughput of the converting process. INTRODUCTIONPeirce-Smith converters (PSC) have been used in copper (Cu) and nickel (Ni) making smelters for more than a century for the purpose of removing iron (Fe) and sulphur (S) chemically associated with copper-nickel mattes through exothermic oxidation reactions. This process is commonly referred to as conversion. In principle, conversion is a submerged injection process, where typically air (or oxygen enriched air), at subsonic velocity (typically < 150 m/s), is laterally blown into liquid matte (Cu-Ni-Fe-S system). Oxygen preferentially reacts with Fe and S to produce iron oxide (FeO), which is slagged off, and sulphur dioxide (SO2), which reports to the process off gas."

Jan 1, 2012

By Pierre Pelletier, Christian Pichetie, Dany Pelletier

"IntroductionDuring 1994, Barrick Gold Corporation, or American Barrick at that period, acquired Lac Minerals Ltd. properties. One of them was the Bousquet Complex. The Bousquet Complex is divided into three distinct sites: one mine (Bousquet 2), one mill (Est-Malartic Division) and one analytical chemistry laboratory (Les Terrains auriferes).The Bousquet 2 orebody was discovered in 1986. An extensive drilling program was initiated during 1987. Its purpose was to define the orebody extent. At the end of 1997, gold production from Bousquet 2 mine reached 1 290 000 oz of gold from a cumulative tonnage processed of 4 175 000 M t.From 1980 to 1990, the Est-Malartic mill was used for the treatment of ore from the following mines: Bousquet 1, Doyon, Francoeur (Richmont mines), Buckshot and 1-20 stope. At present, the mill receives ore from the Bousquet 2 mine.HistoryThe Est-Malartic mill is located close to the town of Malartic in northwestern Quebec. The mill has been in production since the mid-1930s processing mainly clean, free mill gold ore. Active mining from the Est-Malartic mine ceased in 1979 and the mill was switched to custom processing of ore from La Mine Doyon located some 45 km to the west. This custom processing arrangement continued until 1987 when the expanded mill at Doyon became available to process all of the Doyon production. In 1987, Lac Minerals commenced development of a second mine at the Bousquet site located 40 km west of Malartic. This mine, Bousquet 2, is the down dip extension of the La Ronde mine developed by Agnico Eagle. During pre-feasibility evaluations, it was determined that it would be economically more attractive to modify the existing Est-Malartic mill than building a new facility on site. The Est-Malartic mill modifications for processing the high-copper/gold ore from the Bousquet 2 mine began in late 1989 and new circuits were commissioned in mid-1990. Modifications included the addition of both gravity and flotation concentration circuits to recover coarse, free gold and the copper. The existing leaching circuit continued to operate on the copper flotation tailings with some minor modifications to the solution handling systems. A S02/Air cyanide destruction circuit was also added at that time."

Jan 1, 2000

By G. W. Sparkes

The use of CR-39 plastic polymer as a solid state nuclear track detector in the textural analysis of radioactive minerals in geological samples was first described by I.R Basham in 1981. CR-39 autoradiographs provide a detailed, high-resolution image of the in situ distribution of the radioactive minerals within geological samples on both the macroscopic and microscopic scales. This technique is an inexpensive and effective means of obtaining detailed textural information that provides insight into the style of mineralization, its relationship to primary and secondary structures in the host rock, and its association with particular geological features or mineral phases. Although this technique does not provide any information on the identity of the minerals responsible for the radioactivity, the resultant autoradiographs can be used to select regions for further detailed analysis such as petrography, microprobe analysis, or SEM imaging. This paper summarizes the procedure and outlines the appropriate time and materials required for both the exposure and etching of the CR-39 with respect to the intensity of the radioactivity emitted by the geological samples.

Jan 1, 2013

By W. Dingley, G. R. Hoey

"AbstractWear of six types of grinding balls was compared with and without corrosion inhibition in grinding Ni-Cu sulphide and hematite ores in laboratory ball mills. Forged steel balls (Rc 60 to 65) and three types of white cast iron balls (Rc 50 to 65) were susceptible to corrosive wear and two types of stainless steel balls [AISI Type 440C (Rc 65) and AISI Type 302 is; 35)] were relatively immune. The relative wear rates of the five types of hard balls (Rc 50 to 65) were dependent on the corrosivity of the ore. Ranking of the hard balls with respect to wear resistance was consistent for the sulphide and hematite ores in the presence of corrosion inhibition, whereas their ranking was different for the two ores in the absence of inhibition.The electrochemical potential of the grinding balls was measured during grinding and was found to be a useful measurement for assessing the susceptibility of an alloy to corrosive wear. Reduction of ball wear for forged steel and white cast irons with corrosion inhibition was concomitant with a shift of ball potential to less active values. Ball potentials in the presence of inhibition were indicative of non-corroding metal surfaces.IntroductionA PREVIOUS STUDY by the authors (1) showed that corrosion inhibitors - sodium nitrite, sodium chromate and sodium metasilicate - reduced wear of forged steel grinding balls by up to 49% in grinding Ni-Cu sulphide ore. Although the mechanism of wear reduction was not elucidated, it was concluded that corrosion must play a significant role in the wear of grinding media. Remark and Wick (2) of Battelle Pacific Northwest Laboratories have also evaluated corrosion inhibitors for the reduction of metal wear using abrasive and n on- abrasive te sting procedures. Their research was sponsored by 16 companies throughout the world. Preliminary results indicated that anodic inhibitors prevent from one-fourth to one-half of the loss due to corrosion."

Jan 1, 1977

By Jean-Pierre Birat, François Hanrot, Gérard Danloy

Global warming presents an enormous challenge to the steel industry, which is both carbon-intensive and energy efficient. Lean production can provide some short-term emission mitigation, at the level of the Kyoto requirements. In the middle term, more use of scrap will also help alleviate emissions. But to reach much larger reductions in GHG emissions, on a par with the likely targets that will be set after the Kyoto period, the steel industry will have to imagine new production paradigms, which constitutes its most formidable challenge for the years to come. Carbon capture and sequestration, processes leaner in carbon use, electricity and hydrogen from green sources will have to be added together in a patchwork of process routes, which will have to be developed at great risk in the next decade, hopefully through broad international cooperation.

Jan 1, 2004

By Shichang Liu, Hongli Jia, Zhaolian Wang, Maotang Liu, Ltd. Shandong Huate Magnet Technology Co., Fengliang Liu

"Introduce and promote a latest technology and equipment for magnetite. It’s featured of purifying concentrate, lowering tailing grade, high concentrate recovery rate and stable operation. HUATE® New Style Elutriation Electromagnetic Separator is an equipment to obviously upgrade magnetite. The slurry is fed into separation area through feeder. Generated by excitation coil, the working magnetic field distributes specially in separation area. Under the combined effect of the background field, excitation and demagnetic field and gravity, the mineral particles float downwards in the form of magnetic chains, and interact with the rising water. The gangue, non-magnetic particles, lean intergrowth,etc will be discarded as tailing via overflow tank and pipe. While the magnetic will be discharged from concentrate pipe. Its grade is 2%-10% higher than that of traditional magnetic separation equipment. It adopts the technologies of transformer oil cooling, alternative and uniform pulsation magnetic field controlling the tailing grade, larger drum feed-in device, more uniform umbrella scattering discharge and stabler output current, and realizes lower coil temperature raise, stabler magnetic field, more uniform discharge, effective isolation of weak-magnetic area from non-magnetic area, more obvious upgradation and recovery rate and lowering tailing mFe%. It’s more suitable to purify and thicken the high grade and ultrafine iron powder. Compared with traditional elutriation equipment, it adopts new technologies in removing impurities, operation, large-scale, process simplification, water-saving, remote control, etc. It optimizes the comprehensive beneficiation index, expands its application scope, reduces resource wastes and increases economic benefits.INTRODUCTIONMagnetite accounts for a comparatively great proportion in various iron resources. As it’s a kind of strong magnetic mineral, we must adopt the weak magnetic separation equipment in magnetic separation process to realize removing Si and lowering impurities. While it cannot do very well to use the common weak magnetic separation equipment in the final cleaning to remove Si and lower impurities. At present, the plants, adopting single magnetic separation process to realize cleaning and removing Si and lowering impurities, are in the minority. Most magnetite plants adopt the flotation separation process to remove Si, lower impurities and purify the concentrate. Though with stable indexes and high Fe recovery rate, the flotation process is very complicated, high-cost and with lots of environmental pollution. If adopting the weak magnetic separation equipment can realize removing Si, lowering impurities and the final cleaning, the magnetic separation process should be the primary choice."

Jan 1, 2016

By J. B. Mitchell

Using digital image correlation the evolution of strain and strain at the onset of localisation resulting in a hot tear has been determined for alloys AA6111 and Al¬0.5wt% Cu during solidification. High resolution images of hot tear formation and growth were captured during a constrained bar test that incorporated a glass window above a central hot spot region. The images were analysed using digital image correlation software to measure the evolution of displacement and strain based on tracking the motion of discrete features on the as-cast surface of the sample. Temperature data was also acquired with a thermocouple cast into the sample in close proximity to the hot tear. The interval starting from the point immediately after solidification shrinkage ends (the metal pulls away from the glass) and finishing when the first sign of a crack or hot tear is visible to the eye was used to determine strain data. The minimum strain at which strain localisation occurs was found to be 0.0069 in AA6111 and 0.0021 for A1-0.5%Cu.

Jan 1, 2007