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By W. Curlook, V. G. Papangelakis, M. Baghalha

A pressure acid leaching process has been developed for the extraction of metal values, nickel, copper, cobalt and zinc, from base metal smelter slags. The basic concept contemplates cooling the smelter slags through solidification sufficiently slowly to induce a good measure of crystallization; and subsequently, after fine grinding, to pressure leach such slags at around 250°C while applying oxygen overpressure, utilizing smelter byproduct sulphuric acid. High levels of extraction of the slags' metal values are thereby achieved. It has been shown that if the same slags are quenched thereby producing an amorphous structure, the resulting metal extractions are very low. The process is applicable to smelting furnace throwaway/discard/dump slags, as well as to in-process converter slags. By extracting the bulk of the residual base metal values in the throwaway/discard/dump slags, the resulting leached residues are rendered virtually benign vis-à-vis the external environment.

Jan 1, 2004

By Gerald R. Larocque, Donald F. Grenville

"IN APRIL, 1965, the employee relations department (then called the personnel department) was established as a separate function within the company. Its aims and objectives were to hire an effective work force to operate the open-pit mine and the mill, which were at that time under development and construction. It was also directed to develop a sound policy for employee relations to assist the company in maintaining a stable and properly motivated work force, which included the establishment of satisfactory wage rates and fringe benefits, safety, fire protection and security. During the 8 years that the department has been in existence the scope of the company's operations has expanded to include a zinc plant and an underground mine. The work force has enlarged accordingly and now totals 1,680 employees working at the two sites, separated by 34 road miles. To cover the employee relations functions the department has a total of 29 members at the two sites. The department is organized under a superintendent, who has an employee relations supervisor, a safety director and a fire chief reporting directly to him. The employee relations supervisor, with 2 employment officers and 2 clerks, handles hiring, first-stage employee grievanoos, terminations, employee records, and the organization of company-sponsored functions and meetings. Safety, training and security are the responsibility of the safety director, who has 3 safety supervisors, 16 security men, 1 first-aid attendant and one hearing conservation technician to service the two sites. The fire chief operates as a one-man section responsible for plant-wide fire inspections and fireoriented training. Although"

Jan 1, 1974

By C. P. Browning

Copper, as far as we know, was the first metal used by man, and due to the fact that it occurs in many places in the 'native' state, and also to the ease with which it may be shaped, it has played an important part in the evolution of civilization. Copper tools with inscriptions dating back to 6,000 B.C. are known in Egypt, where the metal probably got its start as a useful material in human hands. Just how far back the use of copper in Canada dates is difficult to say, but it was in use by the Indians in the Lake Superior country long before the arrival of the first white man. For many generations the Eskimos also have used copper derived fr0m deposits of the native metal found in the Coronation Gulf district. Due to the metal's many unique qualities, imperishable with age, ancient implements and utensils are apparently as good today as when they were made, having withstood the onslaught of time probably better than objects of any of the other base metals. Copper alloys so well with other metals that today it is second only to iron in its industrial value. Even at the beginning of the eighteenth century the world's production of copper was probably not more than seven thousand tons a year, with Great Britain producing three-fourths of this. One hundred years ago the mines of the United States, Chili, Mexico, Canada, South Africa, Australia, and Tasmania, which now produce about nine-tenths of the copper of the world, were totally undeveloped. Ln 1926 the world production of copper was approximately 1,658,000 tons, which was seventy thousand tons greater than in the preceding year; but growing demand absorbed the increased production, so that the stock of rough copper throughout the world is comparatively small. Of this huge tonnage of the metal, Canada produced four percent, two-thirds of it emanating from British Columbia, nearly one-third from the Province of Ontario, and the balance from Quebec.

Jan 1, 1927

By Brandt Porter, Lawrence K. Nordell, Alexander Potapor

"Improving comminution efficiencies with better machine geometries and motions, improved nip angles, rock movement control, and voids regulation among rocks are some of the next steps to better machine performance. Recent gains (~30%) using high pressure grinding rolls (HPGRS) and vertical roller mills, in theory and practice, are based on Prof. Klaus Schönert’s academic studies (1979–1996) on rock breakage physics. More recently, University of British Columbia Prof. Bern Klein’s studies (2006–present) via the Ph.D. thesis of Z. Davaanyam (2015) further validate theory with practice from laboratory measurements used in this paper.They demonstrated ideal rock compression breakage, within HPGR and vertical roller mill machines using a piston-die apparatus. Similar rock size range is used. The piston-die confine rock breakage behavior. However, these studies do not extend to larger rocks (> 75 mm), and do not demonstrate the influence of rock voids among bifurcation of rocks during comminution. Further, machines fed with larger rock sizes, such as gyratory, jaw, and cone crushers, are not designed or evaluated for geometry nip angle efficiency.Herein we illustrate a performance gain of a new comminution machine, the conjugate anvil-hammer mill (CAHM), first presented at SAG 2011 (Nordell, 2012). The CAHM machine digests rock sizes 400% larger than HPGR, improves rock grip/nip geometry, better improves rock voids, improves surface wear life > 500%, and improves rock containment and slippage during compression. In all, the CAHM machine shows 22 potential improvements over the HPGR. Most importantly, CAHM shows a 50% kWh/ton improvement compared to the HPGR. Our studies use an advanced Discrete Element Method (DEM) computer program called ROCKY. ROCKY simulates moving boundaries, surface wear mechanics, and incorporates rock breakage physics based on the fundamentals of JKMRC T10 protocol [×] with tuned A × b breakage parameters.We calibrate rock breakage in our DEM code to mimicking both UBC laboratory piston-die and HPGR comminution measurements. We then model CAHM with these known ore and machine properties. Differences are illustrated using DEM techniques on each machine, including key points of when each: use geometry; initiate bifurcation breakage; provide a map of particle size distribution by location; illustrate the importance of controlling voids to minimize agglomeration after breakage; machine performance limits; and kWh/ton benefit."

Jan 1, 2016

By Chris Rule

This paper tells the story of the rapid commercial application of stirred milling technology at Anglo American Platinum?s many Concentrators. The first stirred mill ? a 10 000 litre IsaMillTM; the largest at the time, was commissioned in late 2003. The project development work was presented at SAG 2001. This operation was ?proof of concept? and vindicated the decision to scale up the technology; allowing a rapid and extensive roll-out of mainstream regrind mills as well as several further flotation concentrate regrind mills, over the next six years. Currently 23 stirred mills are in operation with 64 MW of installed drive capacity ? this paper describes the projects? roll-out and the significant results achieved to date. Many operational problems have been solved along the way, some of these will be described. The introduction of the technology has seen a step change in metallurgical results and progressively decreasing operating costs.

Jan 1, 2012

By Tapio Leskinen, Jouko Koskinen, Timo Nlltti, Lappalainen Seppo, Pentti Vanninen

"The Courier 300 on-stream analysis system manufactured by Outokumpu has now been in operation at five of the company's concentration plants long enough to give a reliable basis for closer examination of the benefits achieved in control of these processes. The first system was installed at the Pyhiisalmi mine at the end of 1967. Since November 1970, two analyzers have been in operation at Pyhiisalmi feeding the assay data to a process computer which controls the whole plant and does the optimization of the process. In October 1970 the Courier 300 analysis system was installed at S. T. O. LESKINEN J. KOSKINEN the Keretti concentrator of the Outokumpu mine, followed soon by installations at the Vihanti Mine in May 1971, at the new Vuonos mine in November J 971 and at t he Kotalahti mine in December 1971. Since installation of the Courier analysis systems, considerable improvements have been achieved in the control and the economy of the plants. Immediate knowledge of the changes in the process and the possibility for rapid action has resulted in evener production and higher capacity and recovery. The recovery has been increased most significantly at the Vihanti concentrator, which operates on a complex ore. Consumption of chemicals has been reduced at all concentrators. Due to the fact that process control and partly also bilance analysis are not achieved by conventional methods any more, it has been possible to reduce the personnel of the laboratories drastically. Two of the plants, viz. the Pyhiisalmi and the Vuonos concentrators, are computercontrolled. The Vuonos concentrator started operation in January 1972 under computer control from the very beginning. The Pyhiisalmi concentrator has been computer-controlled since 1970. The Courier 300 analysis system was described in detail at the AIME Centennial Annual Meeting (1971). In this paper, less attention is paid to the analysis system. Only the sampling system of the Courier 300 is described in more detail. In the development of sampling equipment, effective use has been made of the company's wide knowledge of the problems involved and the test field offered by its concentrators. The sampling equipment includes secondary samplers and six basically different types of primary samplers, with which most sampling situations can be managed."

Jan 1, 1973

By M. J. Slater

Ion exchange using resins is one of the few processes capable of reducing ionic contaminants in effluents to very low levels. Continuous fluidized-bed ion exchange is an advantageous technique for processing dirty effluents and thin slurries. It also reduces resin inventory and equipment cost compared to fixed packed beds. A simple continuous fluidized-bed unit has been investigated for treating effluents and its performance is described. Breakthrough curves were first obtained from static fluidized fixed beds; these data were then used to determine the required operating conditions for a periodic-flow, countercurrent fluidized-bed ion exchange system. A waste stream, containing about 56 ppm copper, was treated in the continuous system using an extraction fluidized bed depth of 203 cm and a flow rate of 1.22 cm3/ cm2s (900 gph / sq.ft) to yield an effluent containing less than 0.02 ppm copper. A generalized design method is proposed for similar chemical systems.

Jan 1, 1978

By W. K. Gummer

"THE LOCATION of Canada's present aluminum industry is determined by availability of hydroelectric power, and ready access to ocean transport facilities. The chief raw material for the production of the metal is imported by ship over several thousand miles of water. In times of freedom of shipping and uncontested movement this provides the industry with its cheapest method of operation. However, during the early part of the last decade the general conditions of ocean and rail transportation were such that interest in the treatment of materials other than bauxite was greatly stimulated. This was the case not only in Canada, of course, but in most other countries.Canada has no deposits of bauxite and much research was carried out on other aluminous materials, chiefly silicates, in an effort to develop more or less economic and feasible methods of treatment. In the United States, this research was considerably more extensive. Some projects were early shown to be of little or no value, whereas others, including the widely publicized lime-sinter and soda-lime-sinter methods, became important. In North America, however, apart from the application of the sinter method to the hitherto waste-product (red mud) of the normal Bayer plant operation, none of these processes contributed appreciably to the production of aluminum during the war. In certain European countries, on the other hand, largely because of their situation with regard to bauxite deposits, they had a more general application, and Germany, for example, produced alumina from clay, ashes, and slag by at least four methods."

Jan 1, 1952

By W. L. Murphy

The Star Lake property, located 115 km northeast of La Ronge, Saskatchewan is underlain by metamorphosed andesitic tuffs and flows which have been intruded by the dioritic to granitic Star Lake Pluton. Gold mineralization on the Star Lake property was first discovered at Ru h Lake by E. Beveridge in 1959 and by M. and E. Hird in 1961. In 1960 E. Partridge discovered Kahn 18 and Kahn 28. In 1982 the SMDC-Starrex joint venture completed geophysical and geochemical urveys including magnetics, VLF, IP/Resistivity, vegetation, bulk till and oil sampling, followed by drill testing of pecific targets. To date the most ignificant depo it is the 21 Zone which contain drill indicated reserves of 230,000 tons grading 0.5 oz/ton Au . The 21 Zone con ists of quartz with 5-10% (locally > 30%) drusy pyrite, minor chalcopyrite and trace amounts of scheelite, chalcocite and arsenopyrite. The 21 Zone is enclosed by a 25-50 m wide band of mylonitized monzonite. The mylonite occurs in the central portion of a 300 m wide northeasterly trending zone of brittle deformation .

Jan 1, 1986

By Paul Armstrong

THE first discovery of lead and zinc ore on Calumet island was made in 1893 by John Lawn, who then staked a portion of the property now owned by Calumet Mines, Limited. His discovery was developed by James and Calvin Russell, who are said to have shipped a few tons of sorted ore, averaging 39 per cent zinc, 13 per cent lead, and 11 oz. silver per ton. In 1898, the property was being operated by the Grand Calumet Mining Company, who mined and shipped, for treatment in a Belgian smelter, 1,100 tons of ore averaging 32 per cent zinc, 9 per cent lead, and an unreported content of gold and silver. After some indecisive exploration by an American syndicate in 1907, the property lay idle until1910, when the Calumet Metals Company-later reorganized as the Calumet Zinc and Lead Company-re-commenced exploration. After sinking an 85-foot shaft-the McDonald shaft-and doing a few hundred feet of drifting and cross-cutting, this Company, in 1912, erected a 150-ton daily capacity gravity-concentration plant, in which some 800 tons of ore, mined from the McDonald shaft and Bowie pit, were milled. Owing to very disappointing mill recoveries, the property was shut clown and-after several years of idleness-in? 1916 the mill and mining plant were destroyed by fire and the Company went into bankruptcy. In 1918, an unknown operator shipped to an Omaha, Nebraska, smelter 22 tons of ore, probably sorted from the dumps of the Ste. Anne shaft and Galena pits, averaging 44 percent lead, and 0.26 oz. gold and 61 oz. silver per ton. The British Metals Corporation (Canada), Limited, in 1926, optioned the property. They unwatered the McDonald shaft and, after doing an additional 300 feet of cross-cutting and drifting on the 85-ft. level, estimated there were some 33,000 tons of ore between this level and the surface. Surface exploration, including trenching, on other showings on the property gave discouraging results and the option was dropped.

Jan 1, 1941

By K. G. Chipman

IN 1936, the Department of Mines and Resources was formed by the amalgamation of the former Departments of Mines, Interior, Indian Affairs, and Immigration. In the amalgamation, the Geological Survey and the Topographical Survey became the major divisions of the Bureau of Geology and Topography, which is a part of the Mines and Geology Branch which, in turn, is a part of the Department of Mines and Resources. The Topographical Survey was formed by combining the former Topographical Division of the Geological Survey and the air and ground mapping sections of the former Topographical and Air Survey Bureau of the Department of the Interior. The latter organization, previous to 1933, had been known as the Topographical Surveys Branch of the Department of the Interior. The amalgamation of 1936 definitely placed on the Topographical Survey the responsibility for the original mapping required for the development of our natural resources. The war has brought upon us the situation where all work has had to be in the furtherance of the war effort. With decreased staff and limited appropriations, the mapping on those scales which are directly concerned with the natural resources has been confined to the search for oil and strategic minerals. The reconstruction period will produce a different situation, with different problems. The past is behind us and it is necessary to prepare for the future. First, we should consider briefly a few general principles in the making and using of maps, then take stock of what we have, see what the needs are, and consider how we are to meet these needs.

Jan 1, 1944

By D. W. Euler, D. G. Brophey

"In an attempt to address the issue of rising labour costs, and to improve productivity, a laser-based system to guide underground LHDs and trucks has been developed. This comprehensive system is known as the Opti-Trak system.Essentially, the vehicle is equipped with front and rear-mounted lasers which scan a reference strip mounted on the drift back. The vehicle follows this reference strip and in addition, based on reflective bar codes mounted beside the reference strip, initiates certain functions (i.e. dump cycle, speed change, brake check, etc.). Any programming that is drift-specific is handled by the positioning of the reference strips and bar codes. Consequently, the vehicle can easily travel to many different haulageways or branches, providing the reference strip and bar codes are in place.The advantages of this system are an immediate elimination of haulage operator costs and an increase in available hauling time to 7 hours out of an 8-hour shift as compared to the typical 5Y2 out of 8 hours that a manned haulage system offers.This paper describes the Opti-Trak system and the benefits to be realized from automation of mine haulage requirements."

Jan 1, 1994

CONSTRUCTED WETLANDS (CWs) ?Human-Constructed ?Built Specifically to Remove Contaminants ?Can Treat a Wide Variety of Wastewaters Including Stormwater(SW) ?Three Major Kinds ?Pond Wetlands ?Free Water Surface Wetlands (FWS) ?Sub-Surface Flow Wetlands (SSF) ?HSSF & VSSF

May 1, 2009

By W. C. Whittaker

COMPLETED in November, 1943, at a cost of over $1,500,000, Elk River colliery of the Crow's Nest Pass Coal Company, Limited, has been laid out and equipped for an ultimate annual production of 1,000,000 tons and replaces the recently closed Coal Creek plant, which has been operated by the Company for the past forty-five years. The project has involved the opening of mines in three seams, the construction of a complete set of colliery buildings, including a modern preparation plant of 360 tons per hour capacity, and the laying out of the necessary yard tracks and spur connecting the new development with the Company-owned Morrissey, Fernie and Michel railway, which, in turn, connects with the Canadian Pacific railway at Fernie. The colliery is three and a half miles east of Fernie, B.C., near the southern end of the Crow's Nest coal field, which contains the largest and most important body of coal in the Province of British Columbia. The coal-bearing horizon is the Kootenay formation, present in the form of a syncline covering an area of 230 square miles. Most of the coal seams occur in the lower 2,000 feet of the formation, the covering beds being largely coarse sandstones and conglomerates of great thickness, the presence of which accounts largely for the preservation of the coal measures. James McEvoy, in the report of the Geological Survey of Canada for the year 1900, states that the basin appears to contain a fairly constant coal content of nearly 172 feet in 23 seams of a thickness of one foot or over. Coal has been mined in the Fernie district since 1897 and the first shipments were made from Coal Creek colliery in the following year, over the then newly constructed British Columbia Southern railway. Since that time, a total of over 16,000,000 tons of coal has been produced, an average of 350,000 tons per year. The7ears of peak production were 1910, 1912, and 1913, with an all-time high of 924,000 tons in 1913. The lowest output in the history of Coal Creek was that for the year 1933, when only 60,340 tons were produced, the colliery being closed for some months. Present production from Elk River colliery averages 1,150 tons per day, the output being considerably less than it could be were sufficient man-power available.

Jan 1, 1944

By Peter A. Hacquebard

"Two continuous coal zones occurring in a 2500f t (762 m) thick section of the Upper Carboniferous Pictou Group (Westphalian C and D) have been encountered in five offshore wells drilled f or oil and gas in the Gulf of St. Lawrence. They correlate, by means of fossil spores, with thick coals of the Mabou and Inverness coalfields situated at the eastern margin of the Basin. Therefore, the presence of a large submarine coalfield of at least 18000 sq mi. (46 620 km'] is indicated. This compares with an estimated size of 14 000 sq mi. (36260 km' ) for the Sydney Coal Basin.Accessibility is provided only by the small onshore parts of the Mabou and Inverness fields, because farther offshore the coals lie too deep to be mined (below 4 OOO f t ([ 219 m)).Two near-shore coal exploration wells indicate that at Mabou Mines the younger Inverness coals occur at a mineable depth to at least 5 km from land. A structure contour map of this area shows a reserve of 125 million tons in two Inverness equivalent seams that are 8.5 ft (2.6 m) and 4.5 ft (f.4 m) thick. The Mabou coals, however, reach too great a depth close to shore to possess mineable resources.A structure contour map of the Inverness submarine area, based on mine data and one off shore seismic profile, indicates inferred mineable resources of 160 million tons, in two seams that are 7ft (2.1 m) and 4.5 ft (f.4 m) thick . A detailed deep seismic survey will be necessary to substantiate the structure and resource estimates"",Maceral and coal quality percentage diagrams of five column samples of these seams (the 7 Foot and 13 Foot Seams of Inverness Equivalents) show a bright banded coal, high in reactive macerals, which will produce a weak coke unsuitable f or metallurgical purposes. A thermal coal with a rank of H. V. ""B"" Bituminous (0.64% Ro) is present, averaging 12000 btu llb (6 660 kcai/kg), 10% ash and 6% sulphur, of which 60 to 80% is derived from pyrite.Microlithotype profiles of the major Mabou and Inverness coals show characteristic successions that can be used f or seam identification and proved valuable f or structural interpretations.The time of faulting in the major fracture zone on the eastern margin of the Gulf of St. Lawrence Basin has been deduced from coal rank variations. It occurred in pos tPermian, probably Early Triassic time."

Jan 1, 1986

By Š. Šachlová, T. Lokajícek, M. Petružálek, T. Svitek, A. Štastná

During the past 20 years, alkali silicate reaction (ASR) as a cause of concrete deterioration has been studied by a wide range of experimental methods such as microstructural and macrostructural analysis, bulk chemical analysis, X-ray and neutron diffraction analysis, etc. All of these data are compared with expansion values of mortar bars (following ASTM standard C 1260). Recent studies indicate the useful application of non-destructive methods with the aim of better reflecting mechanical properties and the degree of deterioration of real concrete. Ultrasonic testing methods (including ultrasonic pulse velocity UPV) are widely used to determine material mechanical properties and the changes induced by a variety of mechanical or chemical processes. However, only a few laboratory studies of ASR focused on ultrasonic testing of mortar bars. Due to this fact, a heating chamber was designed and constructed to enable ultrasonic sounding of mortar bar specimens while stored in accelerating solution. Regular ultrasonic sounding of mortar bars reveals significant dependence of ultrasonic data such as longitudinal P-wave velocity, signal energy, signal amplitude and signal frequency on mortar bar storage time. Ultrasonic data were subjected to time domain as well as frequency domain analysis. Different storage conditions were used to determine the effect of ASR on ultrasonic parameters. Mortar bars, prepared in the same manner with one type of aggregate, were stored in cold or warm water or in an accelerating warm medium. Ultrasonic data accurately reflects the differences in hardening and deterioration of tested mortar bars due to different storage conditions. Ultrasonic results showed very good correlation with the results of ASTM standard expansion tests and much higher sensitivity to ASR-induced concrete deterioration. Expansion tests showed 1% measured length differences in comparison with up to 80% resolution of ultrasonic data. The ultrasonic testing proved to be a suitable laboratory method for investigating ASR-related processes and could lead to an improvement of standard testing procedures.

Jan 1, 2015

By Bird. M.

As the Cadia mill was the first 40ft diameter SAG mill, commissioned in 1998, its performance, liner and discharge design attracted considerable international attention. Twelve years on, the liner design and the control philosophy are being readdressed to further improve the mill?s performance. A comprehensive series of 3D liner scans, over life of the liner, have been used to calibrate liner mass loss and progressive changes in the liner profile. This data is being used to provide true charge mass and mill filling, plus progressive trajectory profiles over life of liner. This information, along with measures of mill performance over liner life, is being used to select the optimal operating conditions as the liner wears, and hopes to inform future liner design.

Jan 1, 2012

By H. Rozovsky

"AbstractThis paper discusses the methods of handling air in a large asbestos mill presently being completed at the Jeffrey mine of the Canadian Johns-Manville Company in Asbestos, Quebec.The mill, being the largest single asbestos producer in the world and capable of handling over 14,000 tons of ore per day, requires vast quantities of air. A minimum of 2,500.000 c.f.m. is required or about 10 tons of air for each ton of ore milled.Short descriptions of the process and systems requiring this air are given, followed by details of the fans and filters which make up the heart of the mill.This 'draw through' system, located on the top or 12th floor, is an automatically .controlled volume-pressure system creating the required suction to draw .air throughout the mill building and its numerous air systems.The dry mechanical method of milling develops enormous quantities of airborne dust and fibre. A section of this paper is devoted to a description of the multiplicity of dust systems within a system to control, filter, and remove this dust.Finally, the paper describes the method of returning the filtered air to the• working floors or to the outside, with some notes on heat, humidity and dust counts.IntroductionGeneralTHE discussions in this paper deal only with operations where air movement is involved. No attempt is made to delve into production methods.The Jeffrey mine of the Canadian Johns-Manville Company, located about 100 miles east of Montreal, is the largest single asbestos producer in the world, being responsible for over half of Canadian asbestos fibre production."

Jan 1, 1955

By S. Banisi, A. Haji-Zadeh, A. R. Hasankhoei, M. Maleki-Moghaddam

At the concentration plant of the Gol-E-Gohar Iron Ore Company (Iran) three 9m × 2.05m AG (Autogenous) mills (fixed speed) are used in parallel in a dry operation. The test works conducted in a scale down mill with a diameter of 1m indicated that conventionally used "deflector" type liners did not provide efficient environment for grinding. In this research, to improve the grinding efficiency, a new design using low profile end liners incorporating radial ribs of proper height was investigated. In order to determine an appropriate liner design at different operating conditions, a 100cm×10.8cm model mill was used for experimentation. The special design of model mill made it possible to increase the radial ribs height in steps of 6mm up to 18.5mm. The transparent end of the mill enabled accurate trajectory determination by image analysis. The results indicated that the new lower height profile deflectors and 15.5mm-height (14.5cm in industrial scale) radial ribs improved the mill performance while avoiding excessive pressure drop across the mill and wear on the liner. The image analysis showed that the use of new liners increased the distribution of coarse particles across the mill cross section from 28% to 35%. A new liner design was proposed by decreasing the number of liners in each slice from 5 to 4 pieces. The thickness of the inner head liners reduced from 45cm to 30cm and the outer deflector liners replaced by radial ribs. The distance between the feed and discharge inner head liners increased from the original 115cm to 145cm which increased the effective length of the mill by 26%. The new design reduced the weight and volume of end liners by 9% and 23%, respectively. It was predicted that the new liners design increases the mill throughput by 10% and reduces the metal consumption by 20%.

Jan 1, 2016

By J. Elderton

"The combination of A C induction motor and flu id coupling, of either the fixed or variable filling type, constitutes a simple, low cost, highly reliable drive unit, with many applications in the mining field.The paper will, however, concentrate on the variable filling fluid coupling in three principal applications-conveyor starting, infinitely variable speed control for slurry and slimes pumping and dewatering pumps for deep mines. Fluid couplings can be used with standard or custom-built control gear equipment, ranging from the most simple, time-based open loop types, to those having the latest microprocessor techniques.IntroductionThe first industrial applications of fluid couplings included their use in the mining field as hydraulic slip regulators for flywheel generating sets. These installations, usually rated at around 1700 to 2500 hp, were located at mine shafts where the electrical grid transmission lines were not strong enough to cater for the peak power demands of the cage winding cycle. In Canada, the first two significant examples of variable filling fluid couplings for mining were on conveyor drives, at Steep Rock Mines Limited, closely followed by the major iron ore handling term inal on the St. Lawrence River at Sept-Iles. Successful and reliable operat ion of the fluid couplings at these two sites set the pattern for use on many subsequent mining projects throughout the Canadian Continent."

Jan 1, 1986