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By M. Leahy

"Very little is known about the large scale fluid dynamics and associated distribution of copper in an operating electrowinning cell, yet they will have a major influence on mass transfer and plating quality. The CFD model in this work is used to simulate an entire EW cell with 60 cathodes and 61 anodes, or 121 anode–cathode pairs, elucidating for the first time the three-dimensional (3D) flow and copper distribution in an industrial cell. Two methods for the distribution of electrolyte are modelled:1. Downcomer method: electrolyte is fed by a downcomer at one end of the cell, overflowing at the opposite end.2. Manifold method: a horizontal manifold pipe runs the whole length of the cell and feeds electrolyte via small holes in the top of the manifold pipe.The recirculation that develops within each anode-cathode pair, driven by oxygen bubble generation on the anode, is similar to that seen previously in two-dimensional models of single anode–cathode gaps. However a more complex 3D flow recirculation is established, which involves flow of electrolyte down the side gaps (being a path of low resistance for return flow) as well as the usual return flow down the cathode side of each pair gap. The bubble-driven flow is not influenced by the mode of electrolyte distribution.The electrolyte flow due to the manifold and downcomer is somewhat secondary to the bubble driven flow. In the case of the downcomer distribution mode, the high injection velocity causes a very turbulent flow in the first 1–2 m down the cell from the downcomer, with several large vortices developing. This may lead to some sludge particles being entrained into the bulk of the cell.In the manifold pipe case, the jet from each hole is dissipated very quickly, within the first 10–20 cm. The jets are directed into the downward flowing zone of the bubble-driven recirculation, which leads to unstable and periodic behaviour on a large spatial scale.In both the manifold and downcomer cases, there is a marked two-zone vertical stratification in copper concentration."

Jan 1, 2016

By H. A. ?ye

The ISO TC 226 (Materials for the production of primary aluminium) has presently issued more than one hundred standards on the materials: alumina, pitch, petroleum coke, carbon anodes, carbon cathodes, ramming paste, fluorides and refractory). The object of the standardization work is to find methods that both material producers and smelters will accept. Methods that are specific for the operational conditions have been developed in addition to more traditional room temperature methods. Examples of important properties under operational conditions are: Air and C02 reactivity of anodes, Equivalent temperature for baked anodes, Sodium expansion of cathode blocks, Shrinkage and Rammability of paste, Penetration of electrolyte into refractories.

Jan 1, 2006

By D. G. Macintyre

"Potentially economic stratiform barite-sulphide deposits have recently been discovered in Devonian basinal facies rocks of the Kechika Trough of northeast British Columbia. This new mineral district is over 180 kilometres long and includes nine major occurrences, namely Driftpile Creek, Bear, Mount Alcock, Cirque, Fluke, Pie, Elf, Kwadacha and Sika. The Cirque is the largest known deposit, with reserves of atleast 30 million tonnes averaging 10per cent combined lead-zinc and 47 grams per tonne silver. The footwall rocks for the Cirque and other strati/rom barite-sulphide deposits in the area are rhythmically bedded baritic and pyritic carbonaceous black shales, siliceous argillites and cherts of probable Mid to Late Devonian age. These siliceous rocks overlie a succession of proximal to distal turbidites which are the basinal equivalent of Early to Mid Devonian carbonate reefs to the east. The siliceous facies is overlain by deeper-water black shales of probable Late Devonian to Mississippian age.Preliminary stratigraphic and sedimentological investigations suggest that the strati/arm massive pyrite and bedded barite deposits formed in third-order euxinic basins within a northwest-trending structurally controlled trough which, in the southern part of the district, was bounded by carbonate reefs. The exhalative event, which appears to have been accompanied by synsedimentary faulting, took place during the early stages of a major eastward-directed marine transgression that was probably related to rapid crustal subsidence. Dewatering of metal-enriched shales and subsequent brine discharge along fault zones within the trough, with the exhaled brines accumulating in seafloor depressions, is the mechanism envisaged for formation of the deposits. Convective circulation systems may have been established about the more deep-seated faults, in response to elevated heat flow levels."

Jan 1, 1982

By Chris Carr

This paper describes the process employed and the work undertaken to enable the surrender of the mine permit relating to the two tailings deposits at the abandoned Red Mountain Mine site near Rossland, BC. The first phase of the work undertaken was to provide urgent remedial work for protection of the environment, primarily through rehabilitation or replacement of surface water drainage systems. The second phase was to up-grade the water management systems to the appropriate level given their consequences of failure. The final phase of work is to ensure long term geotechnical stability of the facilities to the same level of risk. Establishment of a sustaining fund will facilitate long term monitoring and maintenance of the facilities.

May 1, 2002

In-Situ Leaching (ISL) process plants are low cost producers for uranium deposits where the geology is suitable. In the 1970s, a three-year pilot ISL program occurred on gold ore from the Ajax Mine, Cripple Creek District, Colorado, using a chloride and iodide solution [1]. The test was halted due to poor results. With gold and silver the international ISL progress has been slow; however the potential for low capital expenditure (CAPEX) and operating expenditure (OPEX) with large low grade deposits is real. Unless the metallurgy has been demonstrated there are significant risks which could be fatal flaws to an ISL gold or silver project. The metallurgy of gold ISL projects is far from simple and it is early days with project development.

Jan 1, 2011

By CRO CRO

Elk Valley Coal?s Cheviot Project is located in the Alberta foothills south of the town of Hinton. The mine has been in operation now for the 3 years. The start up and subsequent operation of the Cheviot project has been directly influenced by the Cardinal River Mine. As the Cardinal River Mine was winding down due to reserve depletion in 2004, the price of seaborne traded metallurgical coal jumped to record levels and customers began aggressively seeking new sources of supply. Several months later, the owners of Elk Valley Coal decided to begin mining at the Cheviot mining area, extending the life of the area?s operations by over 25 years. The Cheviot Project had been delayed by low coal prices, ownership changes and a complicated and lengthy regulatory process fueled in large measure by stiff opposition from a number of major environmental organizations. Chief to the startup of the project was the construction of a 23-kilometer-long haul road that would connect the new coal measures to the existing Cardinal River processing and rail facilities. Construction of this road was completed with the first coal truck making its first trip in October 2004. This paper will look at some of original assumptions, the actual mining experiences and the lessons that were learned while moving from the drawing board to the current development as it exists today.

May 1, 2007

By W. L. Ott, C. L. Lewis

"AbstractA technique is described for preparation of palladium sponge and for spectrochemical analysis of the metal in this form. The precision and accuracy of the method are discussed. Analyses are compared with previous spectrochemical analyses of palladium in the black form. Good agreement was found in the two sets •of results and it is concluded that they are more reliable than wet chemical .analyses of the same material.IntroductionFOR SEVERAL YEARS the problem of platinum metal analysis by spectrochemical methods has been under investigation at the Spedtrographic Laboratory, Department of Geological Sciences, Queen's University. The problem, briefly -stated, is as follows: Samples of platinum, palladium,-rhodium, ruthenium, and iridium are received as fine metal powders, called sponge. Direct spectrographic analysis of this material has not been found satisfactory due to its heterogeneity •as regards contaminant metals, which may be present up to a total of one per •cent or more. Further-more, spectrographic standards are difficult to obtain and difficult to prepare accurately by adding weighed portions of contaminant metals to the sponge. The fact that •contaminant metals in original samples are probably alloyed with the major constituent is a further difficulty since complete fusion of these refractory metals proved impractical in the present case as a means of standard preparation. It •has, therefore, been found most satisfactory to dissolve the metals, prepare standards by addition of solutions of contaminant metals, and to reduce both standards and samples to a homogeneous form. A previous paper, by Hawley, Wark, Lewis and Ott (2) dealt with a method for spectrochemical analysis of platinum and palladium in their black form. Since completion of research on the black technique, the possibility of analyzing palladium accurately in its sponge form has• been investigated."

Jan 1, 1953

Outline ?Red Lake Gold Mines ?Red Lake Seismic System ?Applications of Seismic System at Red Lake Mine ?Seismic System Analysis and Customization ?Seismic Software ?Array Design ?Calibration and Source Mechanism ?Auto Picking Optimization ?Acquisition Groups ?Conclusions Goldcorp?s Red Lake Gold Mines ?One of the largest gold producers in Canada ?The operations comprise the former Campbell and Red Lake underground mines, now integrated as the Red Lake Gold Mines (RLGM) ?There are a total of 4 shafts with one internal winze and two main declines beginning at the 21st level ?Daily production approximately 2,600 tons

Aug 1, 2013

By R. C. Carne, R. J. Cathro

"Most of the recent large discoveries of zinc, lead and silver in Western Canada are Paleozoic-aged stratiform deposits that occur within the limits of the tectonic sub-province of the Canadian Cordillera known as Selwyn Basin. Bounded on either side by coeval carbonate platforms. Selwyn Basin trends northwest for 1300 km from northeast British Columbia to Alaska. Paleozoic rocks of Selwyn Basin consist primarily of chert, shale and coarser-grained clastic sedimentary rocks with minor volcanic rocks.The Selwyn Basin deposits have few counterparts elsewhere in Canada, but have a close similarity in geological setting, mineralogy and morphology to well-known deposits such as McArthur (HYC) in Australia, Meggen and Rammelsberg in West Germany, and Sullivan in British Columbia. Recent studies of these deposits have led to an emerging, but now generally accepted, model of ore deposition in which stratabound zinc-lead-silver shale-hosted or ""sedimentary-exhalative"" (sedex) deposits are precipitated in active tectonic environments from metalliferous geothermal brines that rise to the sea floor along deep-seated fault zones. Although their mineralogy and ore metal zoning can be similar to that of volcanogenic massive sulphide deposits, most sedex deposits have only a weak genetic link with volcanism.Sedex mineralization in Selwyn Basin has been identified within three separate ages of shale or its metamorphosed equivalent. The lower Cambrian-age Anvil Camp in central Yukon Territory contains the only producing mine (Faro). Important lower Silurian-age zinc-lead mineralization is at Howards Pass along the Yukon - Northwest Territories border. Barite and zinc-lead-barite mineralization of upper Devonian age occurs across Selwyn Basin. Potentially economic deposits have been found at Macmillan Pass, along the Yukon - Northwest Territories border and in the Gataga District of northeastern British Columbia."

Jan 1, 1982

By J. ?H. Chen

Remote sensing technologies have been applied to numerous fields and already benefited those in improving efficiency and recognition accuracy. Change of streamflow can be devastating to residents living along riversides. Still it is difficult to detect such deathly change in large area scale by traditional field surveys. The research aims at provision of detecting streamflow change using a mathematic method based on remote sensing technologies. The scope is on remote sensing stream images taken during the invasion by Typhoon Morakot, bringing one of the major catastrophes to Taiwan. An algorithm was adopted to deal with streamflow recognition on RGB images. The algorithm is capable of yielding change measured by meters and illustrates how main streams shift. An practical example for the Baolai area surrounded by Laonong stream shows that the streamflow moved 88 meters (36 pixels) toward the downtown area during the invasion by Typhoon Morakot. In addition, the results highlight all dangerous zones (scouring zones) for residents to prevent further potential damage.

Aug 1, 2013

By Robin Sheremeta

What is the goal of every organization when it comes to safety? Everyone Going Home Safe and Happy Every Day Good old days: Era of Death (accidents will happen) Era of Engineering: (Eg. hand rails, limitswitches, machine guards, etc.) Era of Legislation: procedures, laws and regulations (Eg. SWP?s, Mines Act) Era of Behaviour-Based Safety: (eg. STOP program)

May 1, 2010

By Scott Rosenthal

?EMESRT History ?Design Philosophies (DP?s) ?Industry Successes ?Participation Thinking Differently Earth Moving Equipment Safety Round Table ? Use a critical mass to influence Marketing ? Define ?Problems?not ?Solutions? ? Leave the OEM designers to develop solutions Work within the companies to improve purchasing

May 1, 2010

By D. Hu, L. Matzar, J. Hampton, M. Gutierrez

Nanodarcy permeability is common in many oil- and gas-bearing formations requiring unconventional stimulation technologies, such as hydraulic fracturing (HF), which can connect the isolated hydrocarbon-rich pores with a wellbore through induced fracture networks. Even though a dense induced fracture network is capable of accessing economic amounts of hydrocarbons, much of the rock between and very close to the fracture network is still un-accessed and contains extremely low permeability. Inducing fracture networks into brittle rock can create large amounts of micro failures in surrounding regions that are not connected to the wellbore, as can be seen in Fig. 1(a) from the very wide acoustic emissions (AEs) cloud associated with a narrow fracture generation. It is possible in certain types of rock to increase the effective matrix permeability in localized regions based on the damage associated with the surrounding hydraulic fractures and subsequent high stress concentrations along localized pre-existing potential failure zones. To study this problem, laboratory HF tests were performed at true-triaxial stress state in brittle crystalline rock while monitoring AEs. The AE associated with HF was analyzed for source parameters using the moment tensor inversion method called Simplified Green’s Functions for Moment Tensor Analysis (SiGMA). Using the moment tensor for each individual AE event, the mode of failure was determined. Crack slip directions and crack face normal directions were also found, along with the relative volume of individual micro failures as well as a damage parameter. The associated source parameters were used to classify differing regions of damage in the sample induced from HF and correlate these regions of differing damage to the effective drainage region. Shown in Fig. 1(b) is a near-wellbore (NWB) region that contained three times larger average relative volumetric deformation of individual tensile AE events than the average tensile AE event volume from the entire sample. Because of the large difference in micro fracture volumetric deformation for the NWB region compared to the entire sample, predictions of HF induced damage must be included in reservoir drainage predictions.

Jan 1, 2015

By M. A. Sobhi, L. Li

With the continuous reduction of mineral resources at shallow depth, more and more mines have to go deeper beneath the earth's surface to reach the ore zones. This increase in mine depth leads to a natural stress increase, which also raises the stresses around mine openings. This may result in ground instability, including the risk of rock bursts or exceedingly large opening closure. Stope backfilling is a well known solution to improve the ground stability condition. It also has the advantage of reducing the mining wastes disposed on surface, thus helping to reduce the environment impact from the industry. However, most available solutions for backfill design were developed for an isolated stope without taking into account the influence of mine depth, except for a few numerical analyses performed recently by Falaknaz and coworkers for the case of multiple backfilled stopes laying in the same level. In this paper, a numerical study is carried out to evaluate the stresses in backfilled stopes overlying a sill mat. The mine depth and the excavation of the underlying stope below the sill mat are both taken into consideration. Compared to the case of a single isolated backfilled stope, the obtained numerical results show that the stress magnitudes in the overlying backfill are considerably increased due to the excavation of the underlying stope. In general, the stresses increase with mine depth and backfill stiffness, but decrease with an increase in the surrounding rock mass stiffness. These results indicate that the barricade and sill mat backfill design should take into account the excavation of the underlying stope and the mine depth.

Jan 1, 2015

Mine Safety in Chile ?Since the year 2000 fatality rate averages 34 per year ?1% of world mining labour force but 8% of world?s mining fatalities San Jose Mine Safety ?From 1998 to 2010 eight fatalities ?In 2003 mine inspectors recognized no second means of egress and a raise system was developed ?In 2006 182 workers were injured, 56 of them seriously ?In January 2007, there was a fatality after a rock burst, and the government ordered the mine closed ?Less than a year later the mine was back in operations. It had not complied with some of the basic safety measures ordered. One of those measures was to complete the escape way ladder.

May 1, 2011

By K. Heid

"Although concentrated efforts have been made to deplete PCB transformers from the Canadian environment, numerous transformers (as well as ballasts, capacitors and magnets) continue to exist throughout the Canadian mining industry. The existing installed base is slowly being phased out as environmental issues come under increasingly high profile. The following article identifies the potential problems of owning PCB transformers and offers some solutions for their removal, disposal and replacement. IntroductionPolychlorinated Biphenyls (PCB) are synthetic chemical compounds consisting of chlorine, carbon and hydrogen. PCB was widely used in transformers due to its physical properties, including stability, low flammability and non-conductivity. Use of PCB in electrical equipment has been banned since 1977 when the extent of environmental contamination was discovered.Although PCB’s have been outlawed for use in electrical equipment since the late 1970s, safe storage regulations were not addressed until 1988 when a major spill prompted the federal government eventually to issue the storage of PCB Material Regulations in 1992. These regulations replaced the Interim order of 1988 under the Canadian Environmental Protection Act.PCB transformers are usually referred to as askarel filled transformers or as PCB contaminated mineral oil transformers. Askeral transformers were designed to contain high concentration PCB fluids, referred to as askarel. Mineral oil transformers were not designed to have PCB concentrations but were inadvertently contaminated during manufacture or maintenance activities."

Jan 1, 1998

By S. Sillitoe

In mining, as in other business and engineering enterprises, efficient operation depends upon how well and how quickly the lines of communication can function. Mines have used the telephone on and between levels for many years, but in the hoisting shaft maintenance of physical wire connections for communication with the moving cage or skip has been found, for all practical purposes, impossible. A most natural solution was, therefore, the code-bell or buzzer signal system between fixed levels, and this has been standard practice throughout the mining world for many years. However, this system has serious limitations which make it impossible to signal a cage between levels in the shaft, and it requires crude, hazardous or costly methods for signalling during daily shaft inspection. Radio signalling overcomes these difficulties, because the communication medium is never broken and the cage-tender or shaft inspector can safely signal to, and receive signals from, the hoistman at any time from any position in the shaft, whether stationary or in motion. In addition to both audible and visual code signalling, two-way telephone communication and slack cable alarm are facilities made possible in recent commercially developed equipment.

Jan 1, 1949

By R. J. Young, S. J. Tennant, A. D. Drummond

"Gibraltar Mines is located on the western slope of Granite Mountain, 230 air miles north of Vancouver, B.C. and 38 miles north of Williams Lake, B.C. There are four mineable zones within the copper-molybdenite deposit: Gibraltar East, Gibraltar West, Pollyanna and Granite Lake. Open-pit reserves are 358 million tons which average 0.37% Cu and 0.016% MoS2 at a 0.25% Cu cut-off. The Granite Mountain pluton is one of the several Jurassic-Cretaceous intrusions which outcrop along the east side of the Fraser River fault system between Williams Lake and Prince George, B.C. The original Granite Mountain quartz diorite has been metamorphosed by a cataclastic deformation which foliated the rock on a regional scale. Attendant to the development of the foliation, the rock was saussuritized such that the present mineralogy is compatible with that of the greenschist facies. The presence of garnet-bearing assemblages is explained by a restricted increase in water pressure. Pre-mineral intrusive phases within the saussuritized quartz diorite are: (1) leucocratic quartz diorite, (2) aplite and (3) quartz-feldspar porphyry. A late chloritized hornblende dacite dyke is post-mineral. Quartz-feldspar porphyry and leucocratic quartz diorite are locally present on the inner sides of the Gibraltar East, Pollyanna and Granite Lake pits. Their presence suggests a core around which occurs an elliptically shaped sulphide-bearing stockwork. The stockwork, which comprises four ages of vein development, is imposed on and partly controlled by the regional foliation of the samssuritized quartz diorite."

Jan 1, 1973

By A. Sutherland Brown

"The Red Rose Mine is in the Rocher Deboule Range, 8 miles south of Hazelton. The mill camp (elevation 4,000 feet) is on Red Rose Creek, 11 miles by road from Skeena Crossing. The mine camp is one mile northeast and 1,600 feet above the mill camp on a spur of Red Rose Peak.The Red Rose mine was described in the Jubilee Volume, Structural Geology of Canadian Ore Deposits (Davis, pp. 129-131), but regional geology and mine development have progressed to a stage at which a more complete description is possible.The property was first located in 1912, and for the next 7 years was prospected actively for gold and copper on the southern extension of the Red Rose shear. Scheelite was first discovered in the vein in the northern part of the shear in 1923. The Consolidated Mining and Smelting Company of Canada, Limited optioned the property in 1939, and after a drilling program in 1940 the present mine development was initiated in the vein in the northern part of the shear. A 75-ton-per-day mill started operating early in 1942 and continued until 1943. The property was inactive until 195 l, when Western Tungsten Copper Mines Limited leased the property from The Consolidated Mining and Smelting Company of Canada, Limited. A mill, which later was enlarged to 140 tons per day, started operations at the end of 1951. The mine and mill were closed in December, 1954.The mine has twelve levels and sub1evels, and most of the workings are in the plane of the vein (see Figure 2a). The level interval is not constant, but between the lower four levels is 87 feet (100 feet in the plane of the vein). Access is provided by four adits; the 800 (elevation 5,659 feet), 600 (5,920 feet), 300 (6, 133 feet) and 200 levels (6,237 feet). The 600 level is the main haulage, and from it the ore is transported to the mill by aerial tram. From this level an inclined shaft extends in the vein to the lowest level (I, 100)."

Jan 1, 1949

By R. D. Brown

For the first time in years, the spring budgets of federal and provincial governments have not brought down major new proposals affecting the tax burdens of the mining industry in Canada. It seems appropriate to use this unaccustomed period of tranquility to set out an extremely abbreviated summary of the principal features of the federal and provincial income and mining tax rules affecting the mining industry.

Jan 1, 1977