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By R. Laplante, P. Radziszewski, P. De Ciccio

"Predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case. Wear conditions vary with geological formations and compositions. The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American drilling campaigns. Simulation results allow the definition of simple graphical tools that permit the estimation of the potential drill depth remaining on a given drill rod string. IntroductionWear, in many industrial processes, is an undesired phenomenon for which enormous efforts are made to control, if not eliminate. However, wear, in many other cases, is an intrinsic phenomenon of the given process. In such cases, predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case where abrasive conditions vary with geological formations and compositions.A number of studies have been published on drill rod wear especially with regards to the petroleum industry over the last thirty years (Lewis, 1968; Rollins, 1968; Smith, 1978; White 1978; Rowe and Wilson, 1981; Cheng, 1982; Eustes, 1986; Dudman et al., 1989; Besaisow et al., 1990). Of these, most studies covered management techniques (Rollins, 1968; Smith, 1978; White, 1978; Rowe and Wilson, 1981; Besaisow et al., 1990) and some described case histories (Cheng, 1982; Eustes, 1986; Dudman et al., 1989). However, little (Lewis, 1968) was presented that could aid in predicting wear in the particular case of diamond drilling in the metal mining industry.The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate diamond drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American diamond drilling campaigns."

Jan 1, 2002

By H. U. Ross

"INTRODUCTION Extensive studies have been carried on pure gold to determine the various factors that affect its dissolution in alkaline cyanide solutions. With the extension of milling to refractory ores more intensive investigations on the effect of impurities in the ore on the dissolution kinetics are needed. The present work describes experiments carried on refractory flotation tailings with the object to determine how the recovery of gold could be increased. The effect of arsenic and antimony in the ore and the excessive use of lime are discussed. Control of cyanide losses is also dealt with.MECHANISM OF THE GOLD DISSOLUTION REACTION In aqueous cyanide solutions, gold is believed to be dissolved by one of the following reactions:4Au + 8NaCN + O2 + 2H20 = 4NaAu (CN)2 + 4NaOH (1)2Au + 4NaCN + 2 + 2H20 = 2NaAu (CN)2 + 2NaOH + H202 (2)2Au + 4NaCN + H202 = 2NaAu (CN)2 + 2NaOH (3) The first of these, known as the Elsner Equation is supported by )4 3,2,1(several authors while others(5,6) support reactions 2 and 3 known as the Bodlander Equations. According to Habashi(7), the overall reaction for the dissolution process is as shown in equation 2. Most of the workers agree that hydrogen peroxide is produced in the course of the reaction."

Jan 1, 1973

A rough simulated borehole has been developed for the installation and dynamic testing of rock bolts a the WASM Dynamic Test Facility. The rough simulated borehole is used for rock bolts that are sensitive to equipment installation technique or borehole geometry (particularly friction rock stabilisers and resin encapsulated bolts). An extensive axial test program has quantified a difference between the static and dynamic capacity (kN/m of embedment) for friction rock stabilisers once sliding starts. The 47mm split tube bolt has a 50% reduction in embedment capacity (but with significant variation) dissipating 2.7kJ/100mm of sliding per meter of embedment, and the Omega (inflatable) bolt had a 70% reduction in embedment capacity dissipating 6.2kJ/100mm of sliding per meter of embedment. The Omega bolt dynamic capacity remainder at least equivalent to the split tube bolt static capacity.

May 1, 2009

By N. Lecuyer

"During early 1980, pre-production work commenced at the ""Les Mines Gallen"" project, north of Noranda, Quebec. As a result of the acid mine water associated with this property, a major pre-production phase included the installation of a water treatment plant to render the water environmentally suitable.This paper emphasizes the planning, installation and operational factors of the treatment plant necessary to the success of the mining operations and the maintaining of a clean environment.Introduction,T he Gallen Project is a zinc, gold and silver open-pit mining operation approximately 10 kilometres north of Noranda, Quebec. This property has a long history, with initial diamond drilling done in the early 1930s and underground mining taking place between 1953 and 1962. This property was reactivated in 1980, with production scheduled a t a rate of 45,000 ton s per month.Included in the reactivation plans for the property was the installation of a water treatment plant to treat the acidic mine water.Plant DesignThe requirements for the Gallen water treatment plant were two-fold. Firstly, it was necessary to neutralize the acid water and secondly to produce a sludge containing metal hydroxides and sulphates which would be stable when stored, and a clarified overflow meeting governmental regulations to be discharged to the environment.The flow sheet (Fig. I) will explain the process in treatment of the acid water.Acid mine drainage is treated with lime to increase the pH to 9.50. Metals in solution are precipitated as metal hydroxides and the 504 as calcium sulphate. The precipitate slurry is then aerated to convert ferrous iron to ferric iron, which is more stable for storage and disposal.The precipitate is next flocculated with a polymer flocculant and settled in the thickener to produce a sulphate/Hydroxide sludge and a final effluent discharged to the environment."

Jan 1, 1983

By Wendy L. Naysmith

This paper deals with the various options considered and factors that influenced the final selection of the headframe, shaft layout and hoisting systems required at the Impala No 16 Shaft in order to hoist both the required 3 Mt of ore per annum, and transport men, material and equipment between the surface and the underground workings to a depth of 1640 m. The layout and construction method used for what is at present the world?s tallest concrete headframe is discussed together with the integrated hoist room foundations designed to suit multiple mechanical and electrical hoist supplier?s solutions. The mechanical components of the two tower mounted 6,5m 4 rope Koepe hoists and deflection sheaves and their layout is dealt with in detail. Various features of the bearing type, brake units and brake control system are also discussed. Installation of the mechanical and electrical hoist equipment in the headframe took place during the sinking phase of the project and placed severe restrictions on the use of the heavy lifting facilities. This required a well-managed and systematic approach to delivery of the hoist components and associated equipment, as well as close co-operation between all contractors on site.

Oct 1, 2010

By T. G. Carter

"During the early part of the 1980s, four new surface coal mines commenced operation in the Province of British Columbia. Each represented a major investment in both persons and materials in order to protect this investment in one significant area-the fixed portion of the surface coal handling system-a substantial amount of work was undertaken to ensure that the system was well protected from an outbreak of fire. A great deal of effort in this field had already been made by those coal mines which had been in operation for a number of years and experience gained at these operations was utilized in determining the level and extent of fire protection for the new mines.This paper summarizes the major problems, and suggests some of the methods of solution, in providing an adequate degree of fire protection for surface coal handling systems. It will also discuss the potential for gas and dust explosions together with ways to minimize this potential.The Fixed Coal Handling SystemNote: The word ""fixed"" has been used in its present context to denote that part of the coal handling system where the coal is moved via fixed installations such as a conveyor. It differentiates from that part of the system where coal is moved by mobile equipment.The raw coal delivered to the truck dump will undergo two major processes on its way to the rail load out. The first will be at the coal preparation plant where coal of specified quality will be extracted from the raw feed to the plant. If this coal is of metallurgical quality, and sometimes if it is of thermal quality, it will pass through a thermal dryer where part of the moisture acquired during coal preparation will be removed, i.e. the second process. As the complexity of both the coal preparation plant and the thermal dryer is such as to warrant separate considerations they will not form part of this paper. Each of the processes, however, is generally, housed in its own building, thus, containment of any hazards is usually more attainable than those existing or caused in the rest of the system."

Jan 1, 1988

By Perry L. Christian

"Mana/ta Coal Ltd. 's Costello Mine, located seven kilometres east of Estevan, Saskatchewan, has been operating at the present location since 1960. During the past twenty-three years, annual production of lignite coal has averaged 590 000 tonnes. The coal is used for power generation and for industrial and domestic use. Markets, operating techniques, facilities in place and reclamation are discussed. Introduction The Costello Mine (formerly the Klimax Mine) is located in southeastern Saskatchewan, approximately 210 kilometres southeast of Regina and 5 kilometres from the United States' border, as shown in Figure 1. The present mine, 7 kilometres east of the city of Estevan, has been operating since 1960. The history, however, of the Costello Mine and of the Estevan Coalfield dates from the initial settling of the area in the 1880s. Mining initially consisted of burrowing into the side of the Souris River Valley or other hillsides where the coal seam was exposed. Eventually, slopes were put down in the Estevan/Bienfait area and vigorous underground activity existed. In the late 1920s surface strip mining was introduced. The use of strip mining progressed to the point where it completely replaced underground mining in the 1950s and it is the only method in use today. During the past 23 years annual production has averaged 590 000 tonnes. The lowest production was in 1960 when the mine was starting up at 167 000 tonnes and the highest production was in 1977 when production was 1 509 000 tonnes. The Costello Mine controls approximately 11 400 hectares of mineral rights in the Estevan area. This is made up of 4 900 hectares of freehold coal and 6 500 hectares of leases. The area forms a large, irregular shaped configuration. Most holdings are contiguous and adjacent. The mine also owns some 8 400 hectares of surface rights. The lands under the Costello Mine's surface rights control, which are not being used in the mining operation, are leased to local farmers and ranchers. This ensures that the land is used to its full potential, both before and after mining."

Jan 1, 1985

By L. C. Lien

Tower crane layout (TCL) is a typical construction site layout (CSL) problem, which is suitable for a wide range of work assignments and site conditions. Tower crane is one of the key facilities for vertical and horizontal transportation of materials, especially for heavy prefabrication units such as steel beams, ready mixed concrete, prefabricated elements and large panel formwork such as machinery and equipment, and a wide variety of other building materials within a construction site. However, it is a difficult combinatorial optimization problem to determine the locations of tower cranes with materials quantity supply and demand for engineers. Swarm intelligence (SI) was very popular and widely used in many complex optimization problems which was collective behaviour of social systems such as honey bees (bee algorithm, BA) and birds (particle swarm optimization, PSO). This study applied a hybrid swarm algorithm namely particle bee algorithm (PBA) based on a particular intelligent behaviour of honey bee and bird swarms by integrates theirs advantages. This study compares the performance of PBA with BA and PSO for a proposed hypothetical construction engineering of TCL with materials quantity supply and demand problem. Results show that PBA performs better performance than the mentioned algorithms on a proposed hypothetical TCL problem.

Aug 1, 2013

By M. A. Halim, V. I. Lakshmanan, Z. Jankovic

An innovative mixed-chloride process for the separation of iron from lateritic ore is described. The separation of Fe(III) from leach liquor is an important process step for the recovery of nickel and cobalt. The patented process of Process Research ORTECH Inc. uses a lixiviant containing hydrochloric acid (HCl) and magnesium chloride (MgCl2) for the leaching of lateritic ores/concentrates followed by the selective solvent extraction step of Fe(III) over other value metals such as Ni and Co. The use of MgCl2 increases the activity of the hydrogen ion in the lixiviant, which reduces the consumption of HCl in the leaching stage and enhances the formation of HFeCl4-, thereby increasing the solvent extraction efficiency of Fe(III) with ketone. The process produces high purity iron oxide (Fe2O3) and regenerates HCl by the pyrohydrolysis of the FeCl3 rich pregnant strip solution. The developed process flowsheet is in closed loop, economically attractive and environmentally friendly.

Jan 1, 2015

By M. Kalin

"Ecological Engineering, a biotechnological approach to the decommissioning of base metal mining wastes, is being tested on two pits (Gloryholes) in Newfoundland, Canada. Pit #2 has an average pH of 3.5 and flows into Pit #1 where, through additional ground water contribution, the pH is circumneutral, ranging between 5.5 to 7.The AMD in Pit #2 originates from underground workings and exposed massive sulphide on the pit walls. The overflow from Pit #1 averages about 10 L/s with less than 0.2 mg/L of Cu and 40 mg/L of Zn.Ecological Engineering utilizes organic substrate as a source of carbon and nutrients for microbial populations which can generate alkalinity and reduce metals. In 1989, limnocorrals (enclosures of 4 m diameter and approx 3 m depth) were placed in both pits to test the most suitable organic amendment (peat and sawdust). Microbial alkalinitygeneration was evident 95 days after placement of the amendment on July 4, 1989. The pH had increased after 120 days from 3.5 to 4.5 and by day 480 the pH was 7 in limnocorrals in Pit #2. Zinc concentrations in the limnocorrals in Pit #2, dropped from an average of 35 mg/L to about 2 mg/L or less, by day 480.A scaled-up experiment has been under way since August 25, 1990, where 390 m3 are treated in pit #2 and 750 m3 in Pit #1. One hundred eighty days after placement of the amendment, zinc was reduced in the acid Pit #2 from 40 mg/L to 15 mg/L. Research is underway to determine those factors which limit microbial activity."

Jan 1, 1992

The rock mass classification systems were developed for different functions, including support selection, excavation method selection and the determination of rock mass engineering properties for excavation design, among others. This explains in part why we have several rock mass classification systems. It is often cautioned that the rock mass classifications are to be used for preliminary excavation support design, but this caution is now often overlooked and detail/final support design based on the rock mass classification systems. This paper advocates differentiating between rock mass classification for pre-excavation support planning and rock mass classification for at-face excavation performance assessment. It is concluded that most at-face excavation performance problems are attributable to confusing the virgin rock mass rating with the rock mass rating on exposure during excavation, and that this observation is independent of the method of excavation. Procedures are then presented for virgin rock mass rating and for at-face rock mass rating/assessment during excavation.

May 1, 2009

By Karl J. C. Harries

"9.1. INTRODUCTIONIn Chapter 5 of Volume I royalties are dealt with and several topics would appear to be duplicated in this Volume. However, Volume I may be looked upon as a general guide, whereas this Volume is a reference volume. It deals in considerable detail with specific provisions and concepts relating to royalties between private parties. This does not, however, mean that Chapter 5 can be ignored. It should be looked upon as a source of general information concerning royalties between private parties and as a negotiating aid intended to give an overview of various topics. You may well find that in its general approach it will lead you to ask a question which, hopefully, will be dealt with in this Volume .It should be remembered that royalty agreements are agreements with a particular focus, and so the concepts set forth in Chapter 1 apply to them. This chapter addresses a few considerations specific to royalties that will usually form part of an agreement rather than a stand-alone agreement.9.2. FORMAT FOR ROYALTY PROVISIONSIn many of the cases where royalties arise, they are adjunct to, or part of, other arrangements. For example, a royalty may form part or all of the consideration to be given to an owner upon purchase of his property, or it may arise if a joint venturer ceases to contribute to the venture and has his interest converted to a royalty.1 It is with such situations that this section primarily deals; if the royalty is contained in an agreement that is singularly, or primarily, concerned with creating it, then it is just a normal agreement.Commonly, by the time the right to receive the royalty arises, at least some of the other provisions of the agreement have been performed and/or become redundant. For example, in an option agreement the royalty will be a continuing obligation of the optionee, usually arising only after the option has been exercised.2 In a joint venture agreement, a royalty will often arise where the interest of a non-participating venturer has been diluted and converted to a royalty, in which case the recipient will usually become a passive party, entitled only to his royalty, and most of the rights that he enjoyed as an active venturer will cease to be effective."

Jan 1, 2003

By R. W. Schutz

"Titanium possesses an exceptional and wide-range resistance to chlorides and their compounds when compared to most corrosion-resistant engineering alloys (CRAs) used in the chemical process industry. This natural resistance to chlorides stems from titanium’s protective, tenacious, and readily rehealable titanium oxide surface film, which is chemically stable over a wide range of pH and redox potentials in aqueous environments. This passive film explains titanium’s elevated resistance to anodic pitting, crevice and stress corrosion, and erosion-corrosion in aqueous chloride environments.Guidelines for successful selection and application of industrial titanium alloys are derived from an extensive laboratory test database and more than forty years of industrial/chemical service experience. These guidelines are simplified, and alloy corrosion performance is assessed with respect to four basic aqueous chloride service categories where selection or consideration of titanium is highly merited. An overview of historical titanium alloy applications in chloride-rich environments in a wide variety of process industries substantiates their exceptional chloride tolerance. These industrial titanium alloys are cost-competitive with stainless steels and nickel alloys, readily commercially available, and routinely fabricated and welded in the shop and field via well-established methods."

Jan 1, 2002

By E. H. Henderson

MR. R. V. NEILY stated that he had at one time operated at Goldenville. The practice and results are much the same now as in the olden days. Inside plates were then found to be a source of trouble and had been removed. At the Libbey mine, Queen's county, the sulphides carried considerable gold, and $45.00 to $60.00 per ton had been recovered from the concentrates by roasting and chlorinating. Later, concentrates were treated with bromocyanide. Following that practice, a cyanide leaching plant was installed, which did not require concentration of the tailings. Cyanidation brought a recovery of around 95 per cent, with but $300 worth of plant. In Nova Scotia, the ore of each locality presents an individual problem of its own as to treatment required. Ma. W. B. Timm stated that, in the majority of Nova Scotia gold ores, more than 75 per cent of the gold content is free-milling and, naturally, stamps are most efficient for collecting and amalgamating this gold. In Ontario and the West, they had got away from stamps, and perhaps the main reason was that the supply of battery-men, who came from Nova Scotia, had died off. Ball-mills had been installed, which required smaller space and handled large tonnage, even though, as far as amalgamation goes, the stamps were probably more efficient. If concentration is to be done, ore from stamps is usually in better shape for recovery in passing over the tables, as there is no slime. With the ball-mill, flotation is necessary. The better practice, undoubtedly, is to take out what gold is possible before it is all smashed up, as in the ball-mill, though recent developments in the ball-mill make it possible to trap and take coarse gold directly from the mill. In this way, cyanidation is speeded-up, due to saving of the time the coarse gold would take before going into solution. PROFESSOR A. E. FLYNN found it unusual in these days to read anything in favour of the stamp mill, and thanked Mr. Henderson for the excellent paper in which he upholds the stamps and backs his opinion with facts from actual operations. For the typical Nova Scotia ore, containing coarse gold, stamps are un¬excelled. It used to be said that the virtue of stamps is that they brighten the gold for amalgamation. Although this saying is almost classical, it is not true, for gold is never brighter than in the native, untouched state. Any hammering that gold gets makes it more difficult to amalgamate.

Jan 1, 1935

By Hongfei Li, JianLong Wang

This paper introduces the technical characteristics, transformation scheme and production practice of the project in which Copper P-S Converter was replaced by Bottom Blowing Continuous converting for the first time, and introduces the technical achievements obtained by the project. The application practice proves that bottom blowing copper continuous converting technology can completely solve the problems of fugitive off-gas pollution in the ladle transportation, large amount of flue gas and fluctuation of flue gas caused by P-S converting. Comprehensive energy consumption and operating costs of producing blister copper, safety and environmental risks are greatly reduced, and economic, environmental and social benefits are significant. It is one of the preferred technologies for upgrade and to replace P-S converting technology. INTRODUCTION At present, more than 80% of copper production capacity is still using the P-S converting technology with a history of more than 100 years. During P-S converting process, melted copper matte needs to be transported by ladle, and it needs to rotate the furnace body several times, causing a lot of serious environmental and safety risks such as SO2 flue gas emission and low-altitude SO2 pollution. In addition, the high operating cost caused by low rate of air blowing, the short life of the refractory materials and high energy consumption during P-S converting become big problems. Other problems such as large amount of flue gas, low SO2 concentration, large fluctuation of flue gas volume and SO2 concentration, and discontinuous flue gas cause high cost of subsequent flue gas treatment are also needing to be solved. In order to solve these problems during the P-S converting, metallurgical engineer in various countries has spared a lot of efforts to develop continuous blowing process for decades. The continuous converting that have been industrially applied are flash continuous converting, Mitsubishi continuous converting, Noranda continuous converting, Bottom Blowing Continuous converting and multi-lance top blowing continuous converting

Jan 1, 2019

By J. Kazakoff

"The success of gold recovery at the Jolu gold mill depends on many variables. The most important ones are the people, the ore body, plant design parameters, equipment selection and cost control. This paper will briefly hiqhlight the above, the main focus, however will be on the gravity gold circuit.The gravity circuit requires judicious operator attention in order to operate properly. In return the circuit gives immediate visual results for mill peopleIntroductionThe development of the Jolu property to the production stage was carried out quickly, efficiently and economically. The property became a gold producer ahead of schedule and under budget.The Jolu property is a joint venture between International Mahogany Corp., a 70% partner, and Corona Corporation, a 30% partner. Corona Corporation operates the Jolu Gold Mine, located 140 kilometers north of LaRonge and 520 kilometers north of Saskatoon."

Jan 1, 1990

By J. Patterson

"Acid Mine Drainage (A.M.D.) formed from oxidation of disposed pyritic wastes presents a potential pollution hazard for Equity Silver Mines Limited and the mining industry in general. Failure to collect and treat these acidic effluents can eventually affect the quality of receiving streams and endanger aquatic life forms. Treatment and discharge of A.M.D. to the receiving environment must comply with stringent anti-pollution laws.Wastes mined at Equity Silver Mines Ltd. are predominantly acid generating and must be handled according to a materials management plan to minimize impact on the environment. Effluent collection and treatment facilities have been constructed to address the short term environmental concerns with reclamation and research programs being developed to address and monitor abatement measures for control over the long term.The purpose of this paper will be to offer a brief overview of these measures. Key topics for discussion will be: kinetics of Acid Mine Drainage, acid generating potential, water treatment and sludge handling, special wastes, waste dump construction, waste rock amendments, bacteriocide research, simulations, and reclamation measures. Programs designed to evaluate impact on the receiving environment, although they form an extensive part of the program, will not be discussed in this paper.INTRODUCTIONEquity Silver Mines Limited is located in the Central Interior of British Columbia, within the Omineca Division, 35 kilometers southeast of Houston Mining and approximately 575 kilometers by air north-northeast ofVancouver (Figure 1).The deposit consists of three economic mineralized zones: The Southern Tail, Main and Waterline Zones. Mining of the Southern Tail commenced in April, 1980 and was completed in the first quarter of 1984. Main Zone production was initiated during the last quarter of 1983 and the Waterline Zone remains undeveloped to-date. Remaining reserves are in the order of four years contingent on favourable metal prices. The three deposits (Figure 2) occur within a window of interbedded volcanic and minor sedimentary rocks. The older volcanic sequence is bounded on the west by a small granite-like stock and on the east by a gabbro-monzonite complex. All are overlain by a series of younger lava flows."

Jan 1, 1988

By M. Gimpel, R. Galler, T. Antretter, H. Kargl, M. Mikl-Resch, R. Tichy, W. Ecker, G. Pittino

"A computational method based on a continuum-mechanical approach to simulate rock cutting is developed and evaluated. The aim is to obtain the local loading acting at the cutting pick during operation. The explicit FEM is chosen to model the pick-rock interaction. The presented method takes advantage of (i) an advanced material model (ii) a robust contact algorithm and (iii) fast calculations due to parallelization. A damage-plasticity law is chosen and modified with user-subroutines. A user integrated element deletion routine evades critical mesh distortions. Infinite elements at the model boundaries avoid unrealistic deformation wave reflection.INTRODUCTIONExcavation in mining and tunneling is a costly and complex process. Special equipment such as the roadheader (fig. 1) is employed to cut the rock in the excavation process but high material strengths limit their usability (Tockner 1999). Nowadays a challenge is to extend their field of application to harder and more abrasive rock materials. The forces on the pick (fig. 2) are of great importance and determine wear and especially the efficiency of the machine. Figure 2 shows the principle of cutting and the predominant forces. The variation of pick geometry, cutting depth or attack angle will result in an alteration of these forces and determine the efficiency of the process (Tockner 1999). The mechanisms of rock cutting follow the principle of indentation (Kou et al. 1999). Directly under the indenter a hydrostatic stress state evolves causing the material to fail only due to crushing and fragmentation mechanisms. In the close surroundings large strains emerge and tensile cracks are formed but in a further distance the material behaves elastically."

Jan 1, 2015

By Roger Payne, John R. Goode, Feng Gao, James Brown

The Eco Ridge deposit is located in the Elliot Lake mining camp in Northern Ontario, Canada. Between 1955 and 1996, the area produced more than 138,000 t (300 million pounds) of U3O8 and very significant amounts of thorium and heavy rare earths. Based on the NI 43-101 Preliminary Economic Assessment by Roscoe Postle Associates (RPA) dated June 2012, and the economic review by RPA as announced in Pele Mountains’ Press release dated September 12, 2013, the Eco Ridge Mine Project would extract and process 46 Mt of material to produce about 19,000 t (42 million pounds) of U3O8 and about 65,000 t of rare earth oxide (REO) over a 14-year life. This paper discusses process optimization studies including beneficiation and hydrometallurgical testwork. The proposed modified flowsheet includes the flotation and processing of 1) a pyrite concentrate, 2) a dominantly light rare earth elements (LREE) concentrate, 3) a concentrate containing most of the balance of the uranium and heavy rare earths (HREE), and 4) a relatively inert tailings.

Jan 1, 2014

By Pierre Sauvé, Guy Perrault, Armand Savoie, Pierre Trudel

"La Mine Doyon est une entreprise détenue à parts égales par Cambior Inc. et par Minerais Lac Ltée qui en est l'opérateur. Les statistiques de production au 1"" janvier 1990 indiquent que, depuis le début de son exploitation (1980), 10.3 Mt de minerai d'une teneur moyenne de 5,9 g Au/t ont été usinées. Les réserves sont estimées a 10,4 Mt à une teneur moyenne de 6,6 g Au/t jusqu' à une profondeur de-450m.Trois zones minéralisées sont présentement en exploitation. Ces zones sont caractérisées par la présence de veines de quartz-pyrite accompagnées localement de chalcopyrite. Les roches encaissantes sont les schistes a séricite (zone# 1), les roches volcaniclastiques de composition felsique (zone #2) et intermédiaire (zone #2, zone ouest) ainsi que les roches intrusives appartenant au pluton de Mooshla (zone ouest). Toutes ces roches ont subi un métamorphisme régional dont l'intensité correspond à la limite supérieure du facies schiste vert ( -425°C}.Les zones minéralisées sont situées à I' intérieur des zones de déformation et d'altération les plus intenses. L'étude des structures mineures nous indique que la région a subi plusieurs épisodes de déformation ductile a fragile qui sont antérieurs, contemporains et postérieurs al a minéralisation. L'analyse structurale indique également que la déformation majeure est associée à une importante phase de compression orientée N-S a NNE-SSW.L’ensemble des observations suggère que la minéralisation et I' altération associée sont de type épigénétique. La mise en place du minerai se serait effectuée à la fin de l'épisode principal de métamorphisme et de la déformation."

Jan 1, 1990