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By Ray Mason

Marathon PGM Corporation?s PGM-Cu Project in Northwestern Ontario (Figure 1.0) serves as a case study to describe the process involved in advancing a deposit from grass roots exploration to the completion of several feasibility studies and the parallel commencement of environmental permitting. Through the following examination of historical exploration activities, it is clear that these activities are directly related to economic stimulus, mostly measured by downturns in the mineral industry. Other factors that influence the success of exploration advancing to feasibility and new mine development includes the ownership of the mineral claims, which also changes under these economic influences and the crucial role of interactions between the Company, the Crown and First Nations. The Marathon PGM-Cu deposit is hosted within the Eastern Gabbro Series of the Proterozoic Coldwell Complex, which intrudes and bisects the much older Archean Schreiber-Hemlo Greenstone Belt. The sub-circular complex has a diameter of 25 km and a surface area of 580 km2 and is the largest alkaline intrusive complex in North America (Walker et al., 1993). Mineralization at the Marathon PGM-Cu deposit is part of a very large magmatic system that consists of at least three cross-cutting intrusive olivine gabbro units that comprise the Eastern Gabbro Series of the Coldwell Complex (Figure 3.2.4-3). In order of intrusion, the three gabbroic units consist of (1) Layered Gabbro Series, (2) Layered Magnetite Olivine Cumulate (LMOC) and (3) Two Duck Lake (TDL) Gabbro. The relative size and abundance of the gabbroic units decrease in the order Layered Gabbro Series>TDL Gabbro>>LMOC. Late quartz syenite and augite syenite dikes cut all of the gabbros but form a minor component of the intrusive assemblage.

May 1, 2010

By D. S. Conochie

The world is poised for rapid growth in consumption as large, less developed economies acquire greater wealth. It might be expected that there would be a corresponding growth in waste generation, but this might not necessarily be the case. The metallurgical industry has an excellent record of process development which has allowed it to provide a high tonnage supply of low cost, high quality metals. Environmental challenges have been faced and indeed the recycling of scrap iron through the electric arc furnace has made a massive contribution to cleaning up obsolete structures and equipment of past generations. Issues in waste generation and processing still remain, and the expectation for cleaner processing and environmental performance continues to rise. The waste impact of key process developments of the last century and the recent developments in metallurgical waste processing in Canada will be outlined. The potential to use state of the art design tools to produce the next generation of zero waste processes will then be explored.

Jan 1, 2004

By Ralph Harris, Javier Jara

"Oxygen is essential in gold cyanidation. It is supplied to the leaching media by sparging oxygen or compressed air into the cyanidation tank. The rate of oxygen transfer is critical to achieve the desired oxygen concentration in solution.The performance of a novel device for gas sparging recently developed at McGill University is compared to the mass transfer characteristics of the two spargers most used in the gold industry: the four lance configuration and the inverted cone. The distribution of gas and the kinetics of oxygen desorption of the three types of spargers was studied in a 140 litre tank. The oxygen dissolution of the new device is three to five times faster than the other spargers. This could increase the leaching rate and/or decrease the cyanide and oxygen consumption.IntroductionIn hydrometallurgical processing, it is often necessary to bubble gas through a pulp to carry out the wanted reactions. The gas can act to agitate the pulp and it can also supply reactant. The rates of the reactions which require a reactant supplied by the gas are often dependent on the rates of mass transfer from the gas to the solution.A common example of this is gold cyanidation which requires oxygen for gold dissolution. Since the gold containing slurry is rich in other oxygen consuming substances (sulphide like pyrrhotite), it is important to provide enough oxygen to allow complete gold dissolution within the residence time of the cyanidation reactors. It has been demonstrated that the rate of gold dissolution is directly proportional to the dissolved oxygen concentration of the pulp which in turn is proportional to the oxygen partial pressure in the bubble 1 2 3. Improving the rate of mass transfer of oxygen increases the dissolved oxygen concentration of the slurry and therefore improves the rate of the reaction.The rate of mass transfer from a bubble to its surrounding solution increases with decreasing bubble size and increasing gas bubble residence time which in turn increases with decreasing bubble size. The generation and dispersion of small bubbles is thus critical to achieving high rates of mass transfer. Different configurations and devices used to inject gas have different effects on the bubble size and the residence time, influencing the overall rate of mass transfer. Therefore better mass transfer can be achieved by adopting a more efficient method.The methods tested in this report are the four lance configuration (wall spargers), the inverted cone and a new device, designated HCD. The wall spargers and the inverted cone are used widely in the industry today."

Jan 1, 1994

By A. Himsley, E. Byleveld

"With reference to the chemical constraints underlying the ion exchange process for uranium recovery, a generalized view is presented on the actual and the achievable efficiency of the process. The area considered is restricted to acid leach circuits in combination with nitrate, chloride or sulphuric acid elution.A comparison between actual plant results and the chemical requirements shows that:(a) Unless new and better ion exchange resins are developed, no dramatic change in equipment size and resin inventory is""anticipated. (b) Elution efficiency, especially for sulphuric acid, may be improved considerably. More concentrated eluates may beproduced at lower chemical consumption. A possibility of achieving additional purification solely by ion exchange is discussed.IntroductionThis paper presents a generalized view of the actual and the achievable efficiency of the ion exchange processes for urannium recovery. The study is restricted to acid leach circuits in combination with nitrate, chloride or sulphuric acid elution. The ultimate efficiency attainable with ion exchange is dietacted by the chemical reactions underlying the process. The most sophisticated technology cannot change the diffusion rates in the ion exchange resin nor make the uranium loading exceed its equilibrium valueThe design of an ion exchange plant for uranium recovery involves a considerable number of parameters as a result of the wide variety of pregnant solutions produced from different orebodies. Therefore, a generalized approach of the ion exchange process inevitably neglects some parameters which maylead to significant variations in apparently identical situations.The uranium concentration in the pregnant solution, together with its pH, are the principal variables which determine resin loading and residence rime in the ion exchange system. On the elution side, the type of eluant and its concentration will determine the contact time required and the amount of eluant needed to strip the resin. The temperature, the properties of the ion exchange resin, the total dissolved solids in the feed solution and the competing ions are other variables that affect the chemical performance; these, however, may be considered as a correction of the principal parameters if one is interested only in general trends."

Jan 1, 1980

By P. D. Duever, P. J. Readyhough, P. L. Silveston

"The Plastojrost apparatus, developed by Ritter and Juranek in the 1960s has been modified primarily, to automatic temperature control. A limited investigation of carboniferous and cretaceous coal samples showed that both coals undergo the same changes when coked in the Plastofrost unit. Dilatometer plastic range and total dilatation correlated well with the Piastofrost plastic range for the carboniferous Appalachian coal, but not for the cretaceous western Canadian coal. Work to elucidate the characteristics of some western Canadian coals using the Plastofrost is in progress. IntroductionCoke quality is critically affected by the properties of the plastic phase in the coal-to-coke transformation. Since these properties exist in a coke oven and are not measurable, they are approximated by standard laboratory tests, such as free swelling index, plastometry, and dilatometry. Of particular interest to us is the anomalous behaviour of western Canadian coals of cretaceous origin. By many predictive methods, these coals should not produce coherent cokes. When coked in pilot scale test ovens, in fact, they produce cokes of good stability. They typically make up 20% of Japanese coking coal blends and are also used in South Korea, Mexico, Brazil, and several European countries. This anomalous behaviour has been studied in our laboratory<8.9.1O). Plastic properties or rheological tests examine just the external ramifications of the coal-to-coke transformation. To understand the process, however, microscopic examination of the coal and coke seems to be needed. The Plastofrost unit has been shown to be a convenient means to this end."

Jan 1, 1987

By Jürgen Antrekowitsch, Gerardo R. F. Alvear Flores, Mehmet Ayhan, Christoph Zschiesche

Synergies between copper and lead extractive metallurgical processes enable the processing of a broad range of polymetallic materials. However, this complexity also brings some challenges expressed in terms of complex intermediates and final products. For instance, based on the limited solubility of Cu and Ni in crude lead bullion additional phases will appear during the crystallization of the melt. Beyond the need for continuous optimization of metallurgy the control of phase solidification is a further important pillar to achieve a more efficient process by minimizing the amount and cycles of reverts. This paper describes the microscopy study of one of the most relevant intermediate in the Cu and Pb metallurgy, the Cu based alloy and highlights the importance of applying a well-controlled cooling sequence to improve the overall process efficiency. INTRODUCTION One of the key aspects in Aurubis’s 2025 vision is to move towards the implementation of a multi metal recovery strategy. The implementation of this new multi metal vision is supported by the long tradition of the company, founded in 1866 as Norddeutsche Affinerie, and further developed by adopting modern copper smelting and lead smelting technologies for the processing of primary and secondary materials. The combination of these assets have already build the basis for processing of complex materials in the copper and lead circuits implemented in Aurubis’s facilities. The addition of a new smelting facility, will enhance these capabilities. Aurubis current flowsheet combines Cu, Pb and Zn metallurgy. This includes primary smelting of copper concentrate, processing of secondaries (residues, slimes, slags) and recycling materials (scrap, shredder material, e-scrap). These broad range of materials contain not only the mentioned base metals but also a number of minor metals that requires to be properly managed to ensure efficient recoveries and quality of the targeted metals.

Jan 1, 2019

By Song Mao, Local Joint Engineering Lab of Efficient Util of Dominant Mineral Resources from Karst Regions, Guizhou Key Lab of Comprehensive Utilization of Non-metallic Mineral Resource, Xianhai Li, Qin Zhang, unjian Ye, Guizhou University, Wei Cheng, Zhihong Liu

"Phosphate tailing is a kind of industrial waste that emitted from separation processing of phosphate ores, which is usually discarged to the tailing pond without treatment. Recovery of phosphorus from tailings is of great significance for comprehensive utilization of phosphorus resource. Chemical composition of a micro-fine cryptocrystalline phosphate tailing was investigated by X Ray Fluorescence (XRF) and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES), and mineral composition and occurrence of harmful elements were analyzed by optical microscope and Scanning Electron Microscope (SEM), X ray Energy Dispersive Spectrometer (X-ray EDS) and Mineral liberation Analyzer (MLA). On the basis of above, effects of those on mineral processing for phosphate tailing was analyzed. Chemical analysis results in combination with microscopy indicated that there is a certain amount of iron and aluminum and it should focus on the removal of them in separation processing. The cryptocrystalline structure, especially the micro banding structure and micro porphyritic structure indicated that there is quite amount of phosphate in fine particles and it should recovery the phosphorus as much as possible when designing the flotation technology for this difficult separation fine phosphate tailing. This study can provide theoretical guide for efficient phosphorus recovery of from fine phosphate tailing by flotation.INTRODUCTIONPhosphate rocks are vital nonrenewable resources and are essential components in agricultural fertilizers and phosphorous-based chemicals (Gharabaghi et al., 2009). About 95% of the phosphate produced around the world is consumed in the fertilizer industry (page 60 Abdel-Zaher, 2008; Jasinski, 2007). Froth flotation, a solid wettability based separation process is widely used in separation of phosphate rock and shown to be effective (Yehia et al., 1990; Singh et al., 1992; Elgillani and Abouzeid, 1993; Al-Fariss et al., 2013) .Poor selectivity and low recovery for micro-fine particles are hard issues in flotation of middle-low grade phosphate ore because Phosphate resources is becoming poor, fine and complex as the rich ores run out since the 1970s. The rapid depletion of high grade ores forces minerals industry to process low grade ores where finer grinding is required to achieve required liberation of the values, making the fine particle flotation inevitable. the performance of conventional flotation deteriorates rapidly as particle size decreases to below 10-20 µm, depending on the density of the particles (Feng and Aldrich, 1999). To date, fine particle flotation is still considered to be a challenge in mineral processing (Li et al., 2015) ."

Jan 1, 2016

By C. A. Roloff

Demands for increased grinding production, lower-grade are and limited capital have resulted in ever larger grinding mills, some as large as 36ft (/1 m) in diameter and 12,000 hp (8,950 kw). The result is often f ewer machines per plant, with a greater dependence on each machine. To meet these reliability requirements, manufacturers of mills, drives, castings and other components have had to be innovative and creative in their design. Only by thorough review of past designs and practices and by model studies confirmed in field tests can the manufacturer have full confidence in the product. Because of the great interest in large mills, a short review of larger machines is presented. This discussion covers material feeding, bearings, the rotating element, drive trains and material discharge.

Jan 1, 1979

By P. Karimi, A. Amini, H. Abdollahi, A. Mirzaeian

Due to detrimental effects of cyanidation process on the environment in gold industry, application of cyanide alternatives such as thiourea are being highly considered in recent projects. In this study, the extraction of gold from poly metal ore, using thiourea was precisely investigated. The representative sample contained 2.5 ppm Au and 160 ppm Ag. The sample was categorized as oxide gold ore, because the main part of its pyrite was changed to iron oxide and hydroxide such as goethite and lepidocrosite. According to mineralogy, the main gangue mineral was quartz. It shows that gold grains are free and interlocked with quartz matrix. Also, the presence of a high amount of silver in free and sulfide forms and also the low content of other sulfide minerals such as base metal sulfides is a remarkable point of these studies. In the gold extraction process with thiourea, there are several parameters that affect the rate of gold dissolution such as concentrations of thiourea as a gold lixiviant and ferric sulfate as an oxidant, pH and size fraction of feed and leaching time. The influence of these parameters on the gold dissolution rate were investigated and optimized. The results showed that the concentration of thiourea is the most influential parameter which could increase the gold recovery to 71% (at 10 g/kg sample). The optimal amount of ferric sulfate was determined as 6 g/kg sample. Also, the optimal levels of size fraction of feed and pH of solution were 88% under 75 micron and 2 as acidity; respectively. Leaching time was 6 hrs. In addition, this sample was leached with cyanide and the optimized values of size fraction of d88=75 microns, pH=10.45, 2500 ppm of sodium cyanide with time leaching of 24 hours were concluded for maximum recovery of gold in solution. Finally, the results of cyanidation tests were compared to the thiourea dissolution after optimizing all affected parameters in cyanidation process.

Jan 1, 2016

By J. C. O'Rourke

"Gibraltar Mines Ltd. has been operating its open pit copper mine for fifteen years. In that time, over 140 million tons of waste and low-grade material has been placed on the mine waste dumps. Laboratory and in situ testing indicated that enough leachable copper was recoverable from the dumps to justify a leaching operation which would include the construction of a solvent extraction-electro winning plant. The plant, which was commissioned in October 1986, was designed to process 3000 USGPM of dilute copper solution to produce 5000 tons per year of high-quality cathode copper.This paper deals with the start-up and initial year of operation of this plant. The three areas: leaching, solvent extraction, and electrowinning are presented with emphasis on the innovations which were made to help overcome the problems unique to the Gibraltar operation.The Leaching CircuitThe mine waste dumps are leached to produce a pregnant copper solution as feed to the SX-EW plant. To achieve this the dumps are sprinkled with a mildly acidic solution which percolates through the dumps. In travelling through the dumps the solution contacts the surfaces of the liberated copper minerals and dissolves the soluble copper into the form of copper sulphate. The leaching reaction is achieved by a combination of bacterial action to oxidize the sulphides and solubilization of the copper into the acid solution.For the bacterial action to occur the dumps must be near the ideal pH of 1.9 to 2.1 and the necessary elements of the reaction must be present. Because a bacterial reaction is involved there is a lag time between the time when the conditions for bacterial growth are achieved and when the bacteria are in their active growth phase. Laboratory leaching tests with Gibraltar ore indicated that bacterial action takes two to three months to reach its maximum rate (Fig. I).The expected lag time for the planned rate of bacterial leaching prompted Gibraltar to start irrigating the dumps in late June 1986 for a plant start in early fall. The lag time proved to be longer than expected and the dumps took until November to start producing copper at the expected rate (Fig. 2)."

Jan 1, 1988

By W. J. Gibson

"This paper will provide a general assessment of the differences in construction and industrial labour relations. From this outline will come a detailed examination of labour relations in the construction industry and then specifically as related to the construction of mining projects, with emphasis on projects in isolated areas. Development of manpower forecasts, manpower availability, wage escalation formats, working rules, training and recruitment programs, and safety - as related to construction labour relations in the mining industry - are topics which will be dealt with."

Jan 1, 1972

By R. A. Horn, S. M. Telfer

"Canada has a per capita GDP second only to Japan among the G7 countries and a positive trade balance which ranks third among the world&apos;s major economies. International trade represents a very large part of the national economy and as a proportion of GDP is larger than that of all the other G7 countries with the exception of Germany. On the negative side the Canadian current account deficit relative to the size of the economy is significantly worse than that of all major industrial countries, due mainly to the cost of servicing an immense foreign debt and to a large and worsening negative trade balance in manufacturing.The outflow of money may be reduced by increasing the productivity and competitiveness of those sectors of the economy in which Canada already has a leading competitive position and which have the potential for further growth. The mining industry is uniquely qualified in this respect in that Canada is the western world&apos;s largest producer of metals and mineral products and has the geology and the exploration skill to replenish reserves assuming that an adequate level of investment is maintained. In 1989 the minerals industry contributed $8 billion to the country&apos;s balance of payments and with the exception of forestry is the only sector of the economy which has shown consistently increasing foreign earnings over the long term.In recent years there has been a decline in exploration in Canada and a significant increase in countries such as Chile. The demand for hard currency to finance the development of the newly emerging capitalist economies of the CIS and Eastern Europe is also driving these countries to seek foreign investment to allow them to exploit their natural wealth more efficiently. Canada is therefore facing growing international competition for risk capital and in the future its trade surplus will probably decline in the face of lower cost foreign production.Canada rightly exercises a high level of environmental control on its mining operations; however a significant deterrent to investment is the fundamentally unjust application of the many provincial and federal environmental laws, under which a mining company, even if it takes every measure to protect the environment, runs the risk of eternal and unlimited future liability. If this situation is not rectified the effect will be an increase in global pollution as mines in countries with more lax application of law and regulations controlling environmental damage replace those of Canada. Tax benefits and incentives are a more efficient means than arbitrary regulations in minimizing environmental damage."

Jan 1, 1994

By Daniel Hodouin, Robert Lanthier, Yve Dube

"A procedure f or constructing a grinding mill dynamic model is proposed. This model is used in a dynamic simulator of are grinding circuits. The simulator is designed for flexible flow sheets involving different grinding mills and particle classifiers and is able to accept several single variable PID control loops. The dynamic model is validated on a laboratory ball mill, and calibrated to an industrial installation. The simulator is used for characterization of grinding circuit dynamic behaviour and tuning of control strategiesIntroductionThe ore grinding operation is a critical step of the ore preparation process because it is the last comminution stage before the separation of minerals. The properties of the ground minerals to be concentrated, control the quality and efficiency of the separation process. This is why it is important to control properly the operation of the last grinding stage, commonly constituted of a closed circuit ball mill with classifier . To provide an adequate fine product, the grinding operation should compensate for the perturbations of the feed characteristics (size analysis, grindability, etc.). The main objective is to maintain a constant size distribution for providing stable operating conditions to the separation units. Simultaneously another usual objective is to operate the grinding circuit at a maximum capacity.Automatic control applied to grinding circuit s is the appropriate approach to improve its operation. Most frequently average optimal operating conditions are determined from steady -state performances of the circuit , and the automatic control is used for stabilizing the operation at selected values of the process variables . In the traditional approach, one or several single input! single output (SISO) control loops are implemented and empirically tuned. Advanced control practices&apos;!&apos; are based on a quantitative analysis of the circuit dynamics, which could also give a basis for the tuning of conventional SISO 100ps(2)."

Jan 1, 1987

By John E. Udd

"For decades, writers have expressed concern about impending shortages of professionals for Canada&apos;s minerals industry. Even under the present difficult economic circumstances, it is anticipated that the supply which will be available will not be adequate to meet the requirements in certain key areas including mining and petroleum engineering. It is evident that, unless further initiatives are taken, shortages will exist for some time.In this paper, the writer reviews information which relates to both the demand for, and the supply of, persons with advanced-level education in minerals-related disciplines. In particular, a summary is made of the information regarding supply which has been collected by the CIM General Committee on Education for many years.In concluding, the writer expresses some personal opinions regarding imbalances between demand and supply and offers some recommendations for future actions.IntroductionLast year, in a paper which was presented at the Annual General Meeting of the CIM in Calgary, the writer presented a review of the situation regarding professionally educated manpower for the minerals industry, and concluded that indications were that the gap between demand and supply was widening and that the situation could be expected to continue. Since that time, the deterioration of the nation&apos;s economy has caused an appreciable reduction in demand. Simultaneously, a further annual survey by the CIM has shown that the numbers graduating in certain specializations, notably geology and some of the technologies, are rising very rapidly. One of the great concerns of educators at present is that adequate opportunities may not exist for all of those who are now graduating.The danger of the present situation, then, is that a momentary lack of opportunities may cause potential students to choose alternative careers . Because of the lead-time which is involved, it is very possible that this could result in greater shortages during a period of economic recovery or expansion. Action must be taken to ensure that adequate numbers will be attracted to the industry, and this applies particularly to those who have already made the career decision and who are enrolled in minerals-related programs."

Jan 1, 1982

By T. B. Armstrong

"The energy situation is extremely fragile and there is a critical need for energy conservation in the short term and development of new technology in the long term. To keep tabs on energy flow, separate electrical metering is being installed in major industries: The first step reduces demand through peak load control; the second reduces the waste of energy by monitoring energy used per unit of production. IntroductionThe current energy situation is best described as being extremely fragile. The supply of hydrocarbons is being exhausted, while energy needs remain the same in the industrialized nations and are increasing in the Third World.The petroleum era is expected to come to an end in this century, as there will no longer be enough. Gas, coal and electricity will replace some oil as it becomes scarcer during the transitional period before new sources are gradually developed.There is a critical need for energy conservation in the short term. Conservation will, to a great extent be justified by savings, as it will be less expensive to recover energy that is being wasted than to acquire additional energy.The gradual development of new technology is expected to increase energy self-sufficiency in the long term. New energy sources are attracting a growing interest and are becoming more economically feasible and marketable. These rediscovered energy sources include peat, wood, solar, domestic waste and windmills.The sudden increase in energy prices has forced users to look at the way energy is used and find ways to save it. Major industries have found that using separate meters for each department spurs energy responsibility. Energy trim programs now rank in importance with profitability, productivity and with quality.Energy has become such a crucial cost element that better data are essential for planning. Data acquisition varies with plant size and number of utilities. Meters can be read manually or monitored by computerized energy management systems.The relationship of electrical energy input and production levels for a typical uranium mine will be used to demonstrate two steps to energy management. The first step reduces demand through peak load control; the second reduces the waste of energy by monitoring energy used per unit of production.The direct benefit of saving energy is the money saved."

Jan 1, 1980

By J. -M. Bosgiraud, G. Armand, S. Dewonck, L. Richard-Panot

"The Meuse/Haute-Marne Underground Research Laboratory (URL) is located on the eastern boundary of the Paris Basin. The URL started to be built in 2000 (shaft sinking operations) in the framework of ANDRA’s (French national radioactive waste management agency) research program aimed at determining the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive waste (HLW, IL-LLW). Its underground drifts are used to study the Callovo- Oxfordian claystone layer between 420 m and 550 m in depth.The ongoing research program (started in 2006) following the “Technology Readiness Level” (TRL) Scale is more dedicated to technologies improvement and demonstration issue of the different disposal components, even if characterization and monitoring studies are still ongoing.In rock mechanics, at the main level of the URL (located at 490 m), construction and evolution of disposal cells of different size are studied for HLW and IL-LLW packages. A step by step approach, started in 2006, is carried out based on comparison of HM behavior of parallel drifts excavated/supported by different construction methods. These various configurations give insight of the influence of construction method on the EDZ extent and evolution and on the progressive loading of the support, which are key issues to design the Cigéo disposal drifts and excavations.The concept of disposal cells studied for HLW consists in horizontal steel lined micro-tunnels 80 m long and 70 cm in diameter. Several campaigns of tests have been carried out since 2009 in order to demonstrate the feasibility of excavating such micro-tunnels and study their behavior under different conditions (with and without back filling the annular gap between the rock and the casing, watertight or not casing). A full scale demonstrator representative of the benchmark concept has also been excavated, to study its behaviour under thermal loading with heat produced by electrical heaters."

Jan 1, 2015

By T. ?kre, O. M. Dotterud, S. Haarberg, J. Thonstad, G. M. Haarberg

An electrowinning pilot plant has been constructed at Falconbridge Nikkelverk A/S, Kristiansand, Norway. The equipment consists of a mixing tank where the electrolyte composition and temperature are controlled, an electrowinning tank equipped with five cathodes and six anodes of commercial size and design and a dechlorination facility. Electrowinning experiments were carried out in this pilot plant using acid cobalt chloride solution from the cobalt tankhouse. Key parameters were varied to obtain an improved understanding of the cobalt electrowinning process, focusing on the detrimental deposition of cobalt oxide on dimensionally stable anodes. The extent of anode scaling was found to be dependent on the electrowinning conditions. Low pH, temperature and cobalt concentration resulted in less scale being formed, however at the expense of cobalt current efficiency and cell voltage, adversely affecting electrowinning production capacity and energy consumption. When operating at high acidity, pH in the anolyte was higher than in the catholyte, which is believed to be due to H+ ions taking part in the current transport across the diaphragm, migrating out of the bags surrounding each anode.

Jan 1, 2005

By Lan Vu

"The Ferderber mine consists of a series of Archean gold-bearing quartz lenses within a shear zone that crosscuts the central part of the quartz diorite Bourlamaque batholith. This zone has sharp contacts with the enclosing quartz diorite, and on average strikes N70E and dips 65SE. Along the contact with the shear zone, the quartz diorite is chloritized, sericitized and carbonatized. The chlorite schist within the zone is probably derived from mafic dykes.The geometry and distribution of structural features within the Ferderber shear zone suggest a long history of repeated movements. The majority of gold-bearing lenses were first emplaced during a probable early period of brittle shear which resulted from strike-slip movement. They were then folded and pulled into boudins by a later episode of reverse movement that accompanied ductile shear. New mineralized veins were emplaced in the shear zone and deformed at this time.Mineralized veins are dominated by quartz, carbonates, tourmaline and micas. Gold is more common within pyrite where chalcopyrite is abundant and is generally in contact with both pyrite and chalcopyrite at ""triple point"" grain junctions. This intimate association suggests that copper may have played an important role in gold deposition.Recent exploration has shown that the Bourlamaque batholith is cut by many parallel or en echelon shear zones. Study of ""Landsat"" and aerial photographs has indicated a number of linear structures striking ENE-WSW and ESE-WNW which form a conjugate system. The intersection of these two structural trends presents an interesting exploration target."

Jan 1, 1990

By T. S. Grewal, S. C. Gupta, H. Natarajan, T. W. McQuade, N. Nejibulloev-Mamedov

Cigar Lake is one of the world’s largest high-grade uranium mines. The ore mined at Cigar Lake is milled at Orano Canada Inc’s (Orano) McClean Lake mill. The average Cigar Lake ore uranium grade since the start of mining activities in 2014 is 17.8% U (range 8– 28%). To achieve budgeted production of 18 M lbs U3O8/yr the required average feed tonnage to the mill is about 45 kt/yr. Arsenic, occurring as arsenides and sulpharsenides, is one of the major elements of concern associated with Cigar Lake ore. The leaching process is a sulphuric acid leach under oxidizing conditions at near atmospheric pressure. The presence of arsenic in the ore consumes oxidant in leaching as well as ferric sulphate in tailings preparation for arsenic sequestration. The average arsenic grade since the start of mining at Cigar Lake is 0.57% As. Further, the ore is hosted in a matrix of sandstone and clay, which results in poor settling in CCD. The average uranium grade for the balance of Cigar Lake Phase 1 ore is expected to drop to 12.5% U and the average arsenic grade is expected to increase to 1.6 % As, with an annual average peak of 2.5%. Therefore the tonnage throughput required to sustainably meet the production target will increase to 55 kt per year. Orano partnered with Hatch Ltd. (Hatch) to perform a gap analysis study to identify key circuits and equipment in the mill that would require debottlenecking. A METSIM mass balance model of the McClean Lake mill was generated and validated with actual mill operating data. Various feed scenarios were then studied, and the outcome was a traffic light table, which highlighted feed scenarios that exceeded installed capacity of major equipment and circuits. The results provided the basis for the PDC for the pre-feasibility study. This paper will outline the results of the gap analysis, the mass balance model, the feed scenarios and the study undertaken to prepare the McClean Lake mill for the change in ore quality from Cigar Lake.

Jan 1, 2020

By W. J. Kuit

"Complex facilities which provide for the collection, management and treatment of effluents emanating from the Sullivan mine and concentrator tailings were made operational in October 1979. Key features of the system are the use of upgraded tailings ponds for the storage of up to 800 million litres of metals-contaminated effluents, a treatment plant employing lime in a high-density sludge process and a sludge-impoundment facility designed for maximum long-term environmental safety. The completed works are capable of satisfying a difficult range of operating requirements imposed by highly variable weather conditions, drainage flows and soluble metals loadings. Final capital expenditures for the project approached $10 million and annual operating costs are about $0.8 million.This paper discusses the Kimberley effluents treatment project and the major considerations in its development. The treatment process, major plant equipment and initial operating experience are also described.IntroductionCominco Ltd. has worked the Sullivan orebody at Kimberley, B.C. since 1909 and has operated a concentrator some 5 km distant from the mine since 1923. Over the last 70 years, in excess of 120million tonnes of ore have been mined, and production continues at an average rate of 6,500 tonnes per day. It is a well-known fact that the contribution of this operation to Canada&apos;s mining industry and, in particular, Cominco&apos;s development has been significant. However, this success has not been without some undesirable side effects.Unfortunately, the Sullivan is one of only a few major Western Canadian orebodies which may be classed as ""acidic"" in nature. That is, the primary economic minerals, galena and marrnatite, are enclosed in a siliceous host rock with abundant pyrrhotite, but with little or no accompanying alkaline gangue minerals such as calcite and dolomite. The unavoidable consequence of mining such an ore is that contact with air and water generates an acid mine drainage containing various soluble metals orginally present as minerals.This problem also arises in the concentrator&apos;s tailings ponds, which, in the case of the Sullivan, are two separate impoundments of different materials. The 1,100 tonnesl day of ""iron"" tailings are primarily pyrrhotite which is surplus to the requirements of a separate operation that produces sulphuric acid as an intermediate to phosphate fertilizers. Inert gangue minerals with only a minor sulphide content are the main constituents of the 1,200 tonnes/ day of siliceous tailings. Corresponding to the relative proportion of sulphides in the solids, the decant from the iron tailings is substantially more contaminated than that from the siliceous pond."

Jan 1, 1980