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By Yun-Soo Lee, Su-Hyeon Kim, Hyoung-Wook Kim, Joon-Hyeon Cha

A7075 aluminum alloys have high strengths but poor corrosion resistance. In order to improve the corrosion resistance, a clad sheet is suggested, that is the A7075 alloy sheet bonded to A1XXX or A6XXX aluminum alloy sheets which are surface layers with good corrosion resistance. Mechanical properties of the clad sheets are determined by the combination of the component layer sheets, and thermomechanical treatment should be precisely designed when the strengthening methods of the core and the surface alloys are quite different. In the present study, three-layered A6022/A7075/A6022 clad sheets were fabricated by roll bonding process. Simplified processes incorporating a twin roll casting were also suggested in order to reduce the processing cost. Several temper methods composed of rolling, annealing, solution treatment, and aging were suggested in order to optimize the mechanical properties of the sheets. The strengths of the clad sheets were compared with the bare A7075 and bare A6022 sheets.

Jan 1, 2015

By J. L. Miller, R. W. Burns

This paper sets out the various phases of bringing a merchant bar mill into operation from feasibility consideration through financing, design and scheduling to completion.

Jan 1, 1967

By James F. Allan

"The Kipawa yttrium-zirconium prospect is located about 150 km south of Noranda, Quebec. Yttrium-zirconium mineralization occurs in an elongate, regionally metamorphosed and deformed peralkaline complex in the Grenville terrain. The mineralized zone, as defined by =.0.10% Y2O3, is 1300 m long and 10 m to 30 m wide. Zirconium content typically ranges from 0.50 to 1.20% ZrO2, The mineralized zone strikes northwest and dips 20 degrees to 35 degrees to the southwest. It occurs at the structural base of the peralkaline complex in syenite gneiss and calc-silicate rocks and is conformable with both the footwall contact of the complex, and the layering and gneissosity in the enclosing rocks. Minerals of economic interest are eudialyte (sodium-zirconium silicate), mosandrite (sodium-titanium silicate), britholite (calcium-silica phosphate), and a few other uncommon zirconium and titanium silicate minerals.The highest and most continuous yttrium grades occur in the upper part of the syenite gneiss unit in areas containing eudialyte, mosandrite and minor britholite. Yttrium also occurs in britholite in calc-silicate rocks and in mosandrite in syenitic rocks in the lower part of the syenite gneiss unit. Both the yttrium-bearing minerals and yttrium grades are erratic in the lower part of the unit. Zirconium is generally more uniformly distributed than yttrium. A peralkaline granite gneiss phase of the complex intrudes the syenite gneiss and possibly truncates it, and the mineralization, near the southern boundary of the mineralized zone.The mineralized zone is coincident with a radiometric anomaly and discontinuous yttrium and zirconium soil anomalies.More drilling and metallurgical studies will be required to determine the economic viability of the yttrium and zirconium mineralization at Kipawa."

Jan 1, 1992

By James F. Allan

"The Kipawa yttrium-zirconium prospect is located about 150 km south of Noranda, Quebec. Yttrium-zirconium mineralization occurs in an elongate, regionally metamorphosed and deformed peralkaline complex in the Grenville terrain. The mineralized zone, as defined by =.0.10% Y2O3, is 1300 m long and 10 m to 30 m wide. Zirconium content typically ranges from 0.50 to 1.20% ZrO2, The mineralized zone strikes northwest and dips 20 degrees to 35 degrees to the southwest. It occurs at the structural base of the peralkaline complex in syenite gneiss and calc-silicate rocks and is conformable with both the footwall contact of the complex, and the layering and gneissosity in the enclosing rocks. Minerals of economic interest are eudialyte (sodium-zirconium silicate), mosandrite (sodium-titanium silicate), britholite (calcium-silica phosphate), and a few other uncommon zirconium and titanium silicate minerals.The highest and most continuous yttrium grades occur in the upper part of the syenite gneiss unit in areas containing eudialyte, mosandrite and minor britholite. Yttrium also occurs in britholite in calc-silicate rocks and in mosandrite in syenitic rocks in the lower part of the syenite gneiss unit. Both the yttrium-bearing minerals and yttrium grades are erratic in the lower part of the unit. Zirconium is generally more uniformly distributed than yttrium. A peralkaline granite gneiss phase of the complex intrudes the syenite gneiss and possibly truncates it, and the mineralization, near the southern boundary of the mineralized zone.The mineralized zone is coincident with a radiometric anomaly and discontinuous yttrium and zirconium soil anomalies.More drilling and metallurgical studies will be required to determine the economic viability of the yttrium and zirconium mineralization at Kipawa."

Jan 1, 1992

By J. W. Smith, J. Van Dusen, A. Papachristodoulou

"As part of a study to evaluate factors affecting tankroom air quality, the mechanism of aerosol generation from bursting bubbles in electrowinning operations has been investigated. Typically 2 to 3 mg/m2.s are produced in zinc tankrooms. Analysis shows that the rate of production of film drops (geometric mean diameter - 2 urn] increases with decreasing bubble size, and that jet droplets (geometric mean diameter - 20 um) are not produced with gas bubble larger than - 4 mm. Both mechanisms of drop formation and current efficiency are affected by surface active agents, with an over-all reduction in emission of up to 60% to 70% being achievable. A source control system which does not adversely affect electrolyte properties is always preferred, and coalescence of all gas bubbles in to a continuous stream of gas at a single point on the electrolyte surface would eliminate aerosol emissions. This objective was the basis for design of a coalescence device which, in laboratory tests, reduced the emission rate by over 95%.The control device fit s over the electrodes in the electrowinning cell and is partially immersed in the electrolyte. A number of changes in the design which resulted in significant improvement in the performance of the device are reported.Field tests have shown that only about 75% of the aerosol below 10 um can be eliminated by coalescence. The remainder (up to 95% of the total) is controlled by coalescence of droplets, by impaction on the exposed collector surface and gravitational settling.The device does not interfere with operation of the tankroom, handles the effect of surges in power during harvesting, and is simple and inexpensive to maintain. IntroductionDuring the electrowinning of metals (such as zinc and copper) gases are evolved along the electrode surface forming small bubbles. The bubbles travel upwards and burst on the electrolyte free surface generating, in this way, small droplets. Because the electrolyte is often highly acidic or contains toxic materials, the whole process can result in the formation of an aerosol in the atmosphere above the electrowinning cells which poses a serious health hazard to workers in the area, and corrodes equipment."

Jan 1, 1988

By F. Czerwinski

Mechanically fragmented chips of an AZ91D magnesium alloy were transformed into a semisolid slurry within the Thixomolding® system. Microstructural analysis of a material at various processing stages revealed that the cold deformation of the alloy, experienced during chipping, led to the recrystallization and growth of equiaxed grains which were subsequently converted to the globular structures by melting the grain-boundary network.

Jan 1, 2004

By V. I. Lakshmanan, R. Roy

"Zinc is the fourth most widely used metal in the world after iron, aluminum and copper. The primary zinc production is through flotation of zinc concentrate, roasting, leaching and electrowinning. Close to 60% of the metal produced is consumed in galvanizing the steel by making a thin layer of zinc coating on the steel surface by hot dip galvanizing. Process Research ORTECH Inc. has developed an efficient energy-saving sustainable technology for the recovery of zinc from secondary sources such as galvanized steel scrap, dross, dusts etc. The process consists of treating the zinc containing scrap in an alkaline solution to remove the zinc and thereby producing a zinc free steel scrap for recycle. The zinc containing leach liquor is subjected to a solvent extraction process to recover value added zinc oxide as the final product. In this paper, important industrial processes for the recycling of zinc including the PRO process will be discussed. BACKGROUNDZinc is the fourth most widely used metal in the world after iron, aluminum and copper. Global refined zinc output increased by 2.7 per cent to 13.16 million tonnes in 2011 and is expected to increase by an additional 2.4 per cent to 13.48 million tonnes in 2012 [1]. The primary zinc production is through flotation of zinc concentrate, roasting, leaching and electrowinning. Close to 60% of the metal produced is consumed in galvanizing steel by making a thin layer of zinc coating on the steel surface by hot dip galvanizing. Other major usages of zinc are in the production of brass and bronze, die casting and zinc-air batteries. The additional demand for zinc could come from its addition to fertilizers to increase crop yield.While the demand for zinc is increasing, many mines are scheduled to close in near future after being depleted of ore. The mines set to close between now and 2015 are Teck Resources’ Red Dog Mine in Alaska, Minmetals’ Century Mine in Australia and Vedanta Resource’s Skorpion Mine in Namibia [1]. The depletion of resources due to continued use and exploitation is becoming a great concern for the zinc industry. As a result, the sustainability of natural resources for continued societal care has become extremely important. Resource conservation and recovery by recycling with minimal environmental impact is a key element for sustainable development. In this paper, important industrial processes for the recycling of zinc including the PRO process are presented."

Jan 1, 2012

By J. C. White

This paper, after a brief introduction giving the history and geology of the area, deals with mining operations at the Copper Mountain mine of Gaspe Copper Mines, Limited. It discusses development operations, and then goes into the mining methods employed, covering drilling, grade control, blasting practice, loading and hauling, and the road and service machines used.

Jan 1, 1969

By C. H. Sleeman

"The Iron Ore Company of Canada constructed a beneficiation complex in Sept-Iles, Quebec, to concentrate and pelletize earthy red hematite iron ores from the Knob Lake area. The plants were scheduled for initial production during the first quarter of 1973.Many problems have been experienced to date. Difficulties in controlling the process, excessive mechanical failures, design deficiencies and manpower-staffing problems have caused an extended start-up. The problems are now essentially solved and, with the completion of some additional minor modifications, it is expected that the plants will be producing premium iron ore pellets at or near rated capacity within the next immediate period."

Jan 1, 1976

By LUKE O. LINDOE

A major clay products industry in the Medicine Hat area since before 1910 has maintained a continued interest in the clays of the Cypress Hills. For the first forty years the materials used were local red-burning Cretaceous and Pleistocene clays and sands and high-quality stoneware clays of the Whitemud Formation at Eastend, Saskatchewan. Recently a much broader spectrum of raw materials has been brought into use. Including the exposures of the Eagle Butte structure, the Cypress Hills present a 1200 m section of clay-like sediments. Of this 1200 m about 94 per cent, the high montmorillonite shales of the Upper Cretaceous, can be considered useless, or nearly so; the remaining six per cent, all fresh-water beds, presents a wide variety of potentially useful materials. The development of these clay resources is complicated by deep surface creep on the south flank of the Cypress Hills, by largescale slumping on the north flank and by a structural complex in the Eagle Butte area.

Jan 1, 1984

By J E. Curfman

This paper deals with using track-type and rubber-tired machines in the ripping and handling of overburden and ores. The techniques and proper attachments pertaining to the ripping of materials are covered in some detail. Production and relative costs of ripping, as against other methods, are covered in cases pertaining to the mining industry. The use of the refraction seismograph in predetermining the rippability of materials, including a chart relat-ing velocity to rippability, is covered. This operates on the principle that sound waves travel through subsurface materials at different velocities, depending upon the degree of consolidation of the material. It is known that the same factors that affect consolidation also affect rippability. Proper equipping of the tractor to insure maximum efficiency is also covered in some detail. Introduction T HE idea of loosening consolidated materials prior to further handling and processing is probably as old as man. The purpose of ripping is to provide fragmentation of rock and loosening of consolidated materials.

Jan 1, 1965

By Piotr Litwa

The paper focuses on actions aiming at improvement of work safety in mines, particularly in those extracting hard coal, taking into account the characteristics of natural hazards in Polish underground mining and the reasons of mining disasters connected with those hazards. It refers to conclusions addressed to scientific and research centres, drawn during last decade by Commissions appointed by the President of the State Mining Authority in order to investigate reasons and circumstances of incidents, which till now, could not have been accomplished because of financial reasons. Furthermore, the paper presents basic assumptions of the Strategic Research Project Improvement of work safety in mines, announced by the National Centre for Research and Development at State Mining Authority?s President request.

Aug 1, 2013

By John H. Low

Introduction Despite the fact that the .association of magnetite with chrysotile asbestos in the parent producing area of the world, the Thetford Mines - Black Lake area, has been recognized since the ores of that region were first known, magnetic methods were not extensively employed in exploration for asbestos until about the beginning of 1949. Since then, large areas of Ontario, Quebec, and the eastern United States have been prospected both by aeromagnetic and conventional ground magnetic methods. Prior to 1949, a limited amount of magnetic work had been done, notably that of A.H. Miller (1, pp. 184-186), which was carried out in conjunction with the geological survey of the Thetford area by H. C. Cooke (2) in the years of 1930 to 1932. At that time, Miller pointed out that the occurrence of asbestos is associated with very large magnetic 'anomalies' and that, within the Pennington dyke, an area of asbestos- bearing peridotite could be distinguished, by the anomalies, from adjacent areas of non-asbestos ?-bearing peridotite. Since he .also observed large anomalies in what were believed to be ?barren areas, Miller concluded, however, that the magnetometer could hardly be of much or any value in the direct location of asbestos War .and post-war demands on known reserves of asbestos ore, however, stimulated the search for new deposits, and an economical and rapid method of directing speculative drilling was most desirable.

Jan 1, 1951

By W E. vanSteenburgh

The Polar Continental Shelf Project was initiated in 1959 to provide an administrative and logistic vehicle for research in the physical sciences of the land, sea and channel area of the Arctic Archipelago. Most of the scientists are supplied on secondment from the professional branches of the Department. The yearly expeditions number some eighty scientists and sub-professional staff, and they are supported by a fleet of fixed-winged aircraft and helicopters. Accurate positioning is obtained by the use of a Decca Lambda navigational system which is moved as the area of interest is shifted. The Project is designed to accommodate not only physical scientists, but to provide facilities for other scientist who may have an interest in the area under study. The main research scope of the Project includes topographical surveys, hydrography, oceanography, geology, including marine sedimentary studies, gravity, magnetics, seismology, glaciology and geography. The Polar Continental Shelf Project was initiated and recommended by the Committee on Northern Development in 1958.

Jan 1, 1963

By C. J. Sullivan

It is of importance, in prospecting, to distinguish ores of magmatic origin from those derived by the meta-morphism and granitization of source rocks and from those accumulated in certain sedimentary facies. The magmatic ores, which are characterized by their occurrence along fault structures, may be associated with volcanic (including explosive) phenomena. Heat effects are local. The magmatic sequence is well de-fined: kimberlite, with diamond pipes; ijolite, with carbonatites; peridotite, with nickel deposits; norite, with nickel-copper deposits; and diabase-gabbro, with copper-zinc deposits. These deposits are characteristic of Precambrian shields, where a thick sialic crust may rest on basic to ultrabasic magma. The sequence is resumed in the Paleozoic terrains (in a broad sense), with monzonite porphyries and associated copper, copper-gold, and cop-per-lead-zinc deposits.

Jan 1, 1962

By B. Konda, R. Lauer, D. Camilucci, D. Gladwin

"Income based taxes are significant cost elements to be considered in evaluating investment in new mine development. This paper presents the results of comparative analysis of effective income-based tax rates for mining in the Northwest Territories (NWT), selected Canadian provinces and international jurisdictions. The study was done as background to a review of royalty regulations for the NWT. ObjectiveThis paper presents results of comparative analysis of effective mining royalty1 rates, and combined effective mining royalty and income tax rates on selected mine models for the Northwest Territories (NWT), with those for several other jurisdictions in Canada and abroad which compete with the NWT for mining investment.BackgroundThe February 27, 1995 federal budget directed the Department of Indian Affairs and Northern Development (DIAND) to proceed with a comprehensive review and amendments to northern natural resource management legislation in order “to increase revenues and ensure a fair return to the Crown.” DIAND is responsible for the administration of the Territorial Lands Act, and its regulations.The Territorial Lands Act gives the Governor-in-Council the authority to “… make regulations for the leasing of mining rights in, under or on territorial lands and the payment of royalties therefor,…”. In the NWT, the Canada Mining Regulations (CMR) provide for the disposition of mineral rights for most minerals, other than coal, petroleum and related hydrocarbons, in return for the payment of a royalty to the Crown.As part of this review of the NWT mining royalty regime, several computer mine models were developed and tax regimes in a number of jurisdictions were analyzed. Effective mining royalty rates, and the combined effective mining royalty and income tax rates were compared across the jurisdictions. The results presented in this paper are a part of the background work done in preparing a discussion paper on proposed changes to the NWT mining royalty that is expected to be released for public consultation in the very near future."

Jan 1, 1997

By R. G. Achter, E. Wilson

"This paper describes the work undertaken to renovate the Pipe Open Pit drainage system, incorporating measures to improve effluent quality. It describes the technical feat of drilling an l l-inch-diameter hole from the bottom of the open pit for a distance of 1100feet to intersect an underground drift. An innovative method of checking the inclination of this hole is also described. The paper outlines the construction required on the 1500-foot level of the underground mine to facilitate water impoundment and slime settling, as well as the instrumentation for control of water flows. IntroductionThe Manitoba Division of Inco Metals Company operates two mines-an underground mine at Thompson and an open pit at Pipe. The Pipe Open Pit is located 20 miles southwest of the City of Thompson, approximately 400 miles due north of Win nipeg(Fig. 1).Surface diamond drilling of the Pipe ore body was sta rted in 1959. In 1961, a shaft was sunk to a depth o f 1,570 feet to carry out further exploration work and obtain bulk ore samples for metallurgical testing. Site preparation to mine the upper portion of the orebody as an open pit was initiated in 1966 and by late 1967, the removal of silt and clay overburden was in progress. The contractor completed the dredging in the fall of 1969. Over 12 million cubic yards of muskeg, clay and silt was removed, which in some places was 150 feet deep over the orebody. Production began in early 1971, by which time the top three benches of rock had been excavated and the orebody exposed.The Pipe No. 2 Mine main shaft was started in 1970 and completed in 1973 at a depth of 3,160 feet. Development for exploration purposes was carried out on the 1500 and 2460 levels, and permanent pumping facilities were installed.The surface dimensions of the open pit are 2,200 by 1,600 feet, with the long axis striking northeast. The walls are designed with a 45- to 50-degree slope and the ultimate design depth is 720 feet. The present depth of the pit is 520 feet and production capacity is 6,800 tons of ore per mine day."

Jan 1, 1980

By E. B. Wright

THE property of Falconbridge Nickel Mines, Limited, is in Falconbridge township, approximately thirteen miles northwest of Sudbury. From the mine and townsite, a gravel road leads to Sudbury and a branch line of the Canadian National railway to Sudbury Junction. The ore deposit is at the southeastern corner of the 'Sudbury Basin'. It lies in a sheet-like mass, striking in an east-west direction, between norite to the north and greenstone to the south. The general attitude of the ore-body is vertical, but with frequent variations in dip of as much as 10° to the north or south. The deposit is very irregular in outline, the width varying from a few feet to eighty or ninety feet. In the vertical plane, rolls are frequently encountered. Gouge is very often present at one or both ore contacts. The norite to the north shows much jointing. The chief ore minerals are pyrrhotite, pentlandite, and chalcopyrite. The nickel content of the ore is usually double the copper content, average assays ranging from 2 to 2.5 per cent nickel and 1 to 1.5 per cent copper. The ore is of three main types: massive, breccia, and disseminated. The breccia ore, the most common type, consists of sulphides containing rounded inclusions of highly-altered country rock, which, in places, are so large that sorting is necessary in the stopes. In the norite, the breccia ore may grade into disseminated sulphides, which frequently are sufficiently concentrated for profitable mining. In places in the breccia ore, concentrations of solid sulphide masses occur. Until early in 1935, all mining at Falconbridge was by shrinkage scoping, but this method was found to be less and less suitable as greater depth was attained. When mining had reached the 1,000-foot level, ore drawn from large shrinkage stopes was found to have been diluted as much as fifty per cent by sloughing of the wall-rocks, caused by increased rock pressure and insufficient support. It was apparent that this method of stoping was un-suitable and -Mr. E. J. Martin was engaged to superintend the introduction of a method of cut-and-fill stoping.

Jan 1, 1938

By Al Gagnon

Since start-up in 1972, many circuit problems have been encountered, most of which were related to the abundance of fines (-28 mesh), which the circuit had not been designed to treat. The major problems associated with the original circuit included excessive loss of magnetite, reduced throughput during periods of a high proportion of fine coal in the plant feed and low yield in the fine coal circuit. This paper outlines the coal processing circuit at Fording Coal Limited as it exists today, with emphasis on the changes to the original fine coal treatment circuit.

Jan 1, 1978

By Douglas R. Schmitt

In general, knowledge of the state of stress within the Antarctic lithosphere remains largely unconstrained due in part to Antarctica?s inaccessibility and because of the paucity of seismic focal mechanism solutions. As such, an important component of the ANDRILL project was to acquire new information on the stress directions and magnitudes within the upper crust. Extensive fracture mapping of the core and oriented ultrasonic televiewer logging were carried out to provide strong constraints on both stress orientations and the faulting regime. The first hydraulic fracturing stress determinations in Antarctica were also carried out to provide complimentary stress magnitudes. These measurements were accomplished using a wire-line transported hydraulic fracturing system consisting, essentially, of two synthetic polymer packers that were inflated to isolate the 1-m long pressurization interval. The tests were conducted at the end of the drilling and logging in a ~130-m section specially drilled below 1000 mbsf (nearly 1500 m from the rig floor) for hydraulic fractures. This zone was drilled primarily through competent, dense, and low permeability diamicts. The core fracture and televiewer logging information was used to site twenty separate measurements. Classic hydraulic fracturing pressurization records with unambiguous breakdown and fracture closure pressures were obtained in about half of the measurements. The remaining tests provided fracture propagation and closure pressures that are consistent with the classic breakdown curves, but they did not include a clear breakdown pressure and are indicative of the reopening of either natural or drilling induced fractures in the wellbore wall. The preliminary analysis of the results are in generally good agreement with the stress directions indicated by the core fracture logging and the stress regime suggested by the character of the drilling induced core fractures.

Jun 1, 2012