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By D. G. Cerigo, D. M. Bryce, P. H. Jennings

This paper summarizes the results of an experimental and economic study undertaken to evaluate the feasibility of treating an oxidized orebody of about 10 million tons, grading about 0.75 per cent copper, by agitation leaching and by percolation leaching.

Jan 1, 1968

By D. S. Evans

Major Project Blues Over the last two decades, almost every major project has suffered significant cost overruns, significant schedule delays, and/or poor quality work. Exceptions are rare and most projects that tout being ?On Time and Under Budget? have re-cast schedules, significantly modified scope or revised base estimates. The problem isn?t new. In the late 1980?s the Rand Corporation published a study showing that 80% of all major projects had significant cost and schedule overruns. The problem is not restricted to the Canadian environment, or to a specific industry. It is a global problem.

May 1, 2013

By G. Wren

As base metal sulphide resources become increasingly challenging to process, producers seek alternative options to treat concentrates. This study considers the mineral, elemental, and leaching character of a West Australian nickel sulphide deposit (Cosmos Nickel Project). After a brief review of the published work bench top leach tests were conducted to examine the factors which impact the kinetics of nickel sulphide leaching such as particle size, temperature, acid strength and type, concentration of copper sulphate and sodium chloride, and oxygen partial pressure. The effect of sodium chloride was considered due to the common occurrence of hyper saline water at West Australian nickel sulphide mine sites. Ultrafine grinding to an 80% passing size of 10 µm resulted in high nickel leaching efficiency. Moreover, higher concentrations of acid, copper(II) and sodium chloride also gave higher nickel and cobalt leaching efficiencies but arsenic precipitated as FeAsO4. Under the most suitable conditions the extractions of nickel, cobalt and arsenic at 90oC after 6 hours were >95%, 90% and <5%, respectively. The comparison with results from high pressure operations indicates the possibility of using a hydrometallurgical flowsheet based on fine grinding and atmospheric pressure leaching and warrants further investigations.

Jan 1, 2014

By G. A. Gross

"Nearly 90 per cent of the iron ore produced in Canada is derived from iron-formation or bedded iron deposits. About 70 per cent of this consists of concentrates obtained from iron-formation; another 20 per cent was formed by natural enrichment processes.Four principal varieties of iron-formation are recognized -the Algoma, Superior, Clinton and Minette types. Differences in their geology, mineralogy, chemical com-position and environment of deposition are of special significance in their evaluation as ore.The properties of the ores, including grade, beneficiation qualities and minor element content in taconites, metataconites and naturally enriched ores, reflect characteristics of the primary stratigraphie units from which they are derived. A detailed description of the stratigraphie facies is essential for efficient utilization of these source beds."

Jan 1, 1966

By C. O. Aksoy

"Pillars left to ensure the stability of major underground coal mine infrastructure (shafts, drifts) often contain substantial quantities of coal. Recovery of this coal is an efficient use of the resource, but often presents safety hazards; pillar extraction destabilizes the protected structure, and can make its use dangerous. In this study, the stability of an active shaft at an underground coal mine situated in the Soma- Manisa region of Turkey was investigated during the recovery of the coal in the shaft safety pillar.A proprietary three-dimensional finite element analysis model (ANSYS) was used. An elastic-plastic material model utilizing the Drucker-Prager failure criterion was employed. The three-dimensional Drucker-Prager formulation was preferred over the two-dimensional Mohr-Coulomb model because it was thought to more accurately represent the strain hardening behaviour shown by most geologic materials.Stresses and deformations formed around the shaft support were estimated using the model and the results were verified by in situ observations. The results show that stress distributions around the shaft and the subsidence of the shaft support are influenced by the location location of the extraction front and the break angle of the overlying material."

Jan 1, 2005

By C. Juers

Laboratory chromate coating was applied on AM50 and AZ91D alloys and compared to phosphate-permanganate one. Evaluation of the corrosion behaviour was performed using electrochemical DC and AC methods in ASTM water D1384-87. This electrolyte was chosen because it was moderately aggressive and found to give generally good correlations with long period exposure results in atmospheric conditions. Electrochemical impedance spectroscopy was used to determine more accurately the corrosion rates from the analyses of the high frequency capacitive loop. Anodic polarization was applied in order to evaluate the pitting resistance of the different coatings. These results were correlated with weight loss data evaluated from experiments performed by immersion tests in ASTM water D1384-87 and climatic cyclic chamber tests.

Jan 1, 2006

By S. Forgeron

Presentation ? Introduction ? Canadian Underground Coal Mines ? Standardization of Geological Assessment ? Geomechanics Base-line Studies of Canadian Coal Mines ? Cape Breton Development Corporation Prince Mine ? Quinsam Coal Corporation ? 2 North and 4 South Mines ? Smoky River Coal Corporation 5B-4 Mine ? Conclusions and Baseline Comparison ? Figures

May 1, 2001

By A. Scheltema Beduin, H. Oterdoom, A. Haaks, C. Kempe, A. Liedtke

The bath level measurement is applied in many furnaces to keep control of the level of slag and metal or matte inside. The BLM is used mainly in bath processes, and has not seen much evolution in its basic functionality. For a closed DC FeCr furnace, special demands based on the furnace design and extreme process conditions were considered for the design of a bath level measurement in order to collect valuable information about the furnace operation. This paper will describe these demands and the solutions for them, followed by some of the uses for the BLM in a closed FeCr furnace. Some of the future developments on the BLM conclude this presentation.

Jan 1, 2015

By Louis Frost

"A FIRE which forced the sealing -of the east side of Dominion No. 16 Colliery in the Town of New Waterford, Nova Scotia, occurred on October 6th, 1952 (Figure 1).So far as can be ascertained, the fire was first noticed in the roof of No. 7 East Lateral, after a brushing shot had been fired in the pavement. There appears to .be no doubt that this shot •blew out, igniting a small feeder in the roof.Regular air measurements and air samples, taken over a long period prior to the fire, indicated that the ventilation was adequate, for at no time had the percentage of CH4 in the general air current exceeded one per cent in this location. The last regular monthly samples and air measurements, taken at the end of September, showed the condition of the ventilation to be:Return at the Top of No. 8 East WallQuantity .... 27,700 cu. ft. per min.CH4 .......................... 0.32 per centC02 ................................ 0.10 per centHowever, in the week preceding the fire the mine examiner on four occasions had reported small feeders of gas at the face of the brushing in No. 7 East Lateral.Figure 2 is a diagram of the working place where the shots were fired. The face brushing had been shot down at 3 :45 p.m. and cleaned up. Two 'hurdle screens' had also been erected, one close to the face brushing and the other fifteen feet from the face."

Jan 1, 1953

By J. C. Nicholson

The "V" system was first introduced by the West Virginia Coal & Coke Company at their No. 9 mine, Norton. Norton is a small mining village on the B. & 0. railway, about seven miles from the town of Elkins. This year, accompanied by G. D. MacDougall, I visited this mine to obtain first-hand information regarding this modem system and to determine its adaptability to conditions in Nova Scotia. The following is a brief account of my observations. The seam that is being worked is known as the Lower Kittaning, which, at this point, has an average thickness of 7 feet. This includes a band of hard clay varying in thickness from 8 to 14 inches, which occurs about 2 feet from the pavement, also 8 inches of inferior coal at the roof. The latter is not recovered, which leaves to be mined about 5 1/2 feet of clean coal. The roof is slate and shale for the first 30 feet, followed by 40 to 60 feet of sandstone; the total cover is from 80 to 250 feet thick. The seam lies very flat, with a dip of only 2 per cent., and, as the dip is toward the main entrance, it&apos; is in favor of the load, also providing natural drainage for any water the mine makes. As the mine is not gassy, and there is no water to be pumped out, one can understand that mining conditions are practically ideal.

Jan 1, 1924

By R. D. Brown

"Finance Minister Donald Macdonald's budget of May 25, 1976 featured a restructuring of the anti-inflation profit controls and a grab bag of tax changes, some of direct interest to the mining industry. All Canadian taxpayers now will be permitted to write off immediately 100% of mineral and oil and gas exploration expenses included after• May 25, 1976 and before July 1 1979. The cost of acquitting Canadian resource property after May 6, 197.4 from a federal or provincial government will now clearly be included in Canadian development expense, and provincial drilling and exploration incentives received after May 25, 1976 will not reduce exploration and development expense for federal income tax purposes. Under tough new anti-inflation profit controls, all controlled businesses, except distributions, will essentially have one uniform set of rules for• determining allowable profit margins; this allowable margin will be determined by product line or by over-all net margin and will be 85% of the higher of the margin obtained in the five years preceding October• 13, 1975 or the one year preceding May 1, 1976. The basic capital cost allowance system is to continue, but many rates will be revised. The ability to offset losses created through claiming capital cost allowances on leased equipment, etc. against other income will be ended with respect to transactions entered into a/te1• budget night. Miscellaneous other tax changes will raise the low rate base for Canadian-controlled private corporations to $750,000 increase retitement plan contribution limits and reduce the rate of branch tax imposed on branches of corporations resident in a country with which Canada has a comprehensive tax treaty to equal the withholding tax rate on dividends under that treaty."

Jan 1, 1976

By Jarret Thomson

An understanding of groundwater flow is essential for many aspects of mining. This is especially true for the process of shaft sinking through the sandstones of the Manitou Falls Group in the Athabasca Basin of northern Saskatchewan. Experience has shown that the hydraulic conductivities of these sandstones can be relatively high, especially in zones containing natural fractures. To develop a better understanding of the inflow potential into a shaft, a laboratory testing program was undertaken to investigate the hydraulic conductivity of fracture core samples from the Manitou Falls Group. This program involved the measurement of hydraulic conductivities under steady-state flow conditions, while cycling the effective confining pressure across a span that is representative of in-situ conditions. The change in fracture aperture was simultaneously recorded at each confining stress level. It was found that existing relationships relating aperture and flow did not accurately capture the behavior of the samples tested. The effects of fracture staining and infilling were also investigated, and were found to have a notable impact on the hydraulic conductivity.

Jun 1, 2012

By W. M. Goodwin

"IntroductionIN THE preceding paper we have learned about Canada's resources of metallurgical coal. There is an adequate amount in Nova Scotia, a very large reserve on the eastern flank of the Rocky mountains, and a strictly limited supply on the Pacific coast. Added to these is an unknown quantity of coking coal in the Peace River district, at present rather isolated but possibly capable of industrial development in the future.The chief use of metallurgical coal is to make iron and steel. For this, an adequate supply of iron ore is required. So we should now scan the Canadian supply of iron ore, the possibility of its increasing use at home, and the probable markets abroad.Trade in iron ore tends to be international, as is the case with many other raw materials. The present tendency with iron and steel, in contrast, is to keep its manufacture within national boundaries, and there is no evidence that this will change much in the years to come. We should keep these two points clearly in mind when considering the disposal of iron ore from Canadian mines. We should remember, also, that the modern blast furnace and steel plant has such a large output that a correspondingly large population, reasonably compact, is needed to consume its products.Large Ore Supply in East, Small in WestCanada has now four major iron ore fields, well situated to serve adequately the eastern half of the country. Wabana .and Labrador are well placed to serve overseas markets and plants on the eastern seaboard and eastern interior of the United States and Canada."

Jan 1, 1952

By R. Gutray, J. E. Grainger

This paper deals with the use of a cement-deslimed mill tailings mixture for a scraping floor in cut-and-fill stopes at Madsen Red Lake Gold Mines Limited. It describes the mixing and placing procedures and the precautions used with respect to the floor while mining in the stopes. Details of the mix are presented, and advantages and disadvantages discussed. The paper concludes with a brief outline of the costs.

Jan 1, 1966

By M. N. Pons, E. Benizri, B. Laubie, A. Bani, Université de Lorraine LRGP, P. Kidd, A. J. M. Baker

"Serpentine (i.e. ultramafic) outcrops in Europe cover more than 10,000 km2 and have a low-fertility and low-productivity, making them unattractive for traditional agriculture. In general, these areas are slowly abandoned by local farmers, affected by strong rural exodus and landscapes undergo a process of closure. However, ultramafic landscapes have the potential to provide multiple ecosystem services that can contribute to Europe’s goals towards insuring food security, production of renewable raw materials and renewable energy. Phytomining (agromining) aims at cultivating metal hyperaccumulator plants that are able to accumulate Ni and other strategic elements from metal-rich soils and transport them to the shoots (>1%), which can then be harvested as a bio-ore. Such metal-rich biomass can be used to recover highly valuable metals, e.g. nickel (Ni) and also to produce energy (heat, electricity). Nickel agromining can thus offer an eco-efficient alternative to classical pyro- or hydrometallurgical processes without disturbing the soil cover and the geology from soils and rocks that would be considered as low grade ores or sterile material for conventional mining methods.Phytomining agroecosystems can lead to better soil resource efficiency and can offer a fully integrated, new agromining agriculture that could cover thousands of km2 in Europe, benefit local communities with a sustainable rural development and provide a wide array of ecosystem services which will need to be optimised under a life cycle assessment methodology:1. Production of bio-sourced metal products2. Production of energy biomass3. Restoration of soil fertility for conventional agriculture (Ni stress)4. Limiting Ni intake by local populations and farmers5. Use and conservation of local biodiversity (plant and soil fauna and microflora) as cultivated ecosystems6. Store carbon in cultivated soils7. Enhance pollination activity at landscape level.Nickel agromining could therefore change the economical balance in historically-disadvantaged ultramaficregions of Europe"

Jan 1, 2016

By W. A. Gow, V. F. Harrison, H. H. Mccreedy

A semi-continuous bench-scale, countercurrent-decantation system, in which the ore was moved countercurrently to the flow of leaching solution, was used to conduct acid-leaching tests on uranium ore with the aid of bacteria. This method, which involved a low degree of agitation, was successfully applied to extract uranium in practical amounts and at practical rates. The acidity of the leaching solution was the main variable investigated in the bench-scale tests done at the Mines Branch, Ottawa. Over 90 11er cent of the uranium was extracted in a six-stage system. The results suggest that this technique could be ap-plied in the utilization of bacterial oxidation and leaching as a method for treating Elliot Lake uranium ore.

Jan 1, 1969

By M. Epiney, A. Ghahreman, R. Kim1and

"In the presence of sulfidic refractory ores, increasing the dissolved oxygen (DO) concentration can positively affect the gold leaching rate. To identify the role of DO in gold cyanidation, electrochemical behavior was studied in the presence of 3 different ores. Sample 1 was a low sulfide pyrite ore, contained 5.14% pyrite, 0.19% galena and 3.09% S. Sample 2 was a pyriticore as well, contained more sulfide as 8.35% S, and 12.4% of pyrite. Sample 3 was a tailing of silicate gold ore, still containing75 g/tAu, 0.13% Pb and 0.18% S. Gold cyanidation kinetics were studied by cyclic voltammetry (CV) and chronoamperometry tests. With sample 1, the gold oxidation peak current density from CV curve was increased to 1.38mA/cm2under oxygen injection, while it was only 0.66 mA/cm2with air injection. From chronoamperometry test, the reaction rate was also faster under oxygen injection. Sample 2 showed similar behavior with sample 1, but the gold oxidation peaks higher than sample 1, i.e. 1.75 and 2.27 mA/cm2, under air and oxygen injection, respectively. However, it seemed that the gold oxidation was impeded by sulfide ions for a longer period. In the presence of sample 3, the gold oxidation peak was the highest among three ores –2.75mA/cm2under oxygen injection, because of its lowest sulfide content. However, from chronoamperometry test, it was also shown that the gold oxidation was impeded because of a significant amount of Pb in the ore sample.INTRODUCTIONIt is well known that gold is leached under oxidative condition (Marsden &House, 2006). Through the most representative and oldest gold leaching technique, cyanidation, more than 90% of gold can be selectively leached from an ore. According to Elsner’s equation, gold is leached in cyanide solution by forming cyanide complex [Au (CN)2–], and oxygen is consumed as an oxidant(Eq. 1)."

Jan 1, 2017

By I. C. Edwards, D. C. Smith

THE milling plant of Bicroft Uranium Mines Limited at Ban-croft, Ontario, was one of the first in Canada to employ ion excl1ange for the selecti1•e recovery of uranium from acid leach liquors. The ion ex-change circuit started operating early in November, 1956, and by June 1 I959, had handled more than two million tons of pregnant solution containing I,830,000 pounds of U3Os. Each column had been saturated and eluted about 430 times. The ion exchange columns are the conventional fixed bed type. Uranium is eluted from the resin with a sodium chloride-sulphuric acid solution and is precipitated continuous-ly with magnesia. After filtering and drying, the precipitate, or "yellow cake," is packaged in drums for shipment to the refinery.

Jan 1, 1962

By J. Kronsteiner, E. Kabliman

"In the present work, we developed a Smart Process Control Toolkit (SProC) as a single simulation environment for the modelling of materials microstructure and its interaction with the local microchemistry during manufacturing of semi-finished products. This toolkit supports the data communication between sub-sequent processing steps such as casting, homogenization, pre-heating to deformation, etc. The thermo-kinetical simulation software MatCalc of MatCalc Engineering© GmbH was used for modelling of precipitation kinetics, such as formation of primary and secondary phases and their evolution. An import/export functionality of the precipitation distribution after each processing step was implemented to follow the parameter history. For the evolution of the local microstructure, a Mean Dislocation Density based Model (MD2M) was used. This model consists of two parts: (1) Flow Stress Model for calculation of the total strength during the deformation and (2) Static Recrystallization Model for account of the recrystallization and grain growth after the deformation. Validation was done by a comparison of experimental and simulated hot compression tests of a conventional AA2024 alloy.INTRODUCTION Optimization of a semi-finished products quality, elimination of typical production issues and cost savings are of a great demand for supply industries. However, it is currently not feasible to investigate the whole manufacturing process in detail at an industrial level. Concerning the processing parameters, one must understand the correlation mechanisms between macroscopic properties and microscopic material behavior. Numerical simulations, which could reproduce the real processing conditions on the one hand, and employ a physically based modelling on the other, are thus attracting a lot of attention and their power is no longer under the question. It is well known that e.g. the total strength of the material depends directly on distribution of precipitation particles and mean grain size. In order to follow their evolution during the manufacturing process beginning from casting to the final semi-finished product, and thus be able to control the process, one should use the techniques which would at the same time reproduce experimental processing conditions of real size objects (e.g. sheet, extrusions, etc.) and account for the evolution of a local microstructure and its interaction with the microchemistry. A commonly used approach is to implement a model which would describe the evolution of microstructure based on a dislocation density approach into a user defined material subroutine of some finite element solver. There is, however, also an influence of the manufacturing process by e.g. the evolution of a local microchemistry (formation, transformation and dissolution of the precipitation particles) on the microstructure and thus the macroscopic material behavior. Thus, a method is needed to follow the variable history through the simulation of the whole production chain."

Jan 1, 2018

By A. Deneys

This paper reviews industrial gases used in primary copper production. Copper smelting industrial gas demand has steadily increased since the first commercial oxygenconcentrate smelting in 1952 [1]. In copper production oxygen for smelting is the dominant industrial gas use followed by oxygen for converting. Nitrogen is finding increased use in copper smelters. Nitrogen is used for porous plugs for copper converting and anode refining [2-5]. Nitrogen can be used for concentrate drying [6,7] and is also used in some Ni-Cu smelters as a coolant in Peirce-Smith converting [8,9]. Industrial gas supply options of cryogenic or adsorbent based on-site plant or cryogenic liquid delivery are detailed.

Jan 1, 2007