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By J B. McConnell

The Thompson smelter has three unique features which form the basis ~f its design: fluid bed roasters which treat nickel concentrate filter cake from the mill, as well as the flux, in order to achieve partial desulphurization; the use of electric furnaces for the smelting of the partially desulphurized, preheated roaster product; and the disposal of slag by water granulation and slag slurry pumping. The installation consists of three fluid bed roasters, each feeding an electric furnace. Nickel concentrate is received at the smelter via pipe line. It is thickened and filtered, and the filter cake, together with siliceous flux, is fed through rotary bin feeders and reciprocating double-gate seals into the fluid bed roasters. Air injected into the roasters through club-head tuyeres oxidizes part of the sulphur and associated iron in the concentrate. The heat of reaction dries and heats the charge. Roaster product is recovered from the gas stream in cyclones and from the roaster bed through automatic valves.

Jan 1, 1963

By Marcelle A. Hauseux

"The Turgeon Lake granite lies 5 miles north of Baie Johan Beetz, Quebec, at the eastern margin of the Grenville Province. The rocks are classed as granites, granulites, quartzites, biotite schists and gneisses, and amphibolites. The granite's uraniferous character is manifested by phosphuranylite, uraninite, and metamict .zircons associated with magnetite. Field anomalies occur in irregular pods, conformable with the tectonic foliation, in bands roughly paralleling sedimentary bedding. Associated features diagnostic of uraniferous granite are smoky quartz, brick-red feldspar, magnetite and a coarse to pegmatitic grain size. The granite is chemically and physically heterogeneous. Metasediment-granite contacts are diffuse or sharp, and usually conformable to bedding. The regional foliations within all rock types are coherent, and sedimentary structures are often preserved within both metasediments and granite. Autometasomatism probably was a strong granitization agent.A uranium reconcentration into fold-axial zones from original sediments which have been highly granitized during at least two phases of folding is suggested from the available data."

Jan 1, 1977

By Yujing Jiang, Xuezhen Wu, Bo Li, Tomomi Iura, Gang Wang

"Yielding bolt has been widely used for rock reinforcement in mining and civil engineering in high stress conditions. However, the interaction mechanism of yielding bolt and matrix mass is still not clear at present, and no analytical model is available to predict its reinforcement effect quantitatively. In this paper, the mainstream yielding rock bolts were reviewed firstly. After that, a coupling model is proposed to account for the interaction between yielding bolt and matrix mass. Based on the plane strain axial symmetry assumption and the incremental theory of plasticity, equilibrium equations and compatibility equations of matrix mass, and also the response of yielding rock bolt are deduced theoretically. The proposed method was programmed in Visual Basic development environment, and a semi-analytical solution for the coupling model is achieved. The reinforcement mechanism of yielding bolt in conventional tunnelling is clearly demonstrated through an illustrative case study. The reinforcement effect of yielding bolt is estimated quantitatively, and the distribution of axial force along the bolt is presented. In addition, the validity of proposed method is verified by numerical simulations. INTRODUCTIONHigh stress in surrounding rock mass can cause serious stability problems such as massive squeezing in soft rock and rock burst in hard rock. It is observed that many conventional rock bolts failed when experiencing large displacement, which implies that they are too stiff to sustain large deformation and dynamic conditions (Stillborg, 1994; Hoek et al., 1995). Yielding bolt, which can also be called energy-absorbing bolt, has been widely used for rock reinforcement in mining and civil engineering for these conditions (Neugebauer, E., 2008). This paper focuses on the static reinforcement effects of the yielding bolts with analytical method and numerical simulations."

Jan 1, 2015

"THE Canadian Advisory Committee on Coal Research, which is commonly known as CACCR, has been in existence for the past five years and has held annual meetings during that period. This Committee is comprised of representatives from: the Mines Branch, Fuels and Mining Practice Division, Ottawa; the Geological Survey of Canada; the Dominion Coal Board; and the Provincial Research Councils and Foundations. It embraces all coal research in Canada that is sponsored, for the most part, by Government funds.To bring the country's coal research activities to the notice of the Canadian coal industry, the Coal Research Committee of the Coal Division, C.I.M., passed a resolution at the 1964 business meeting in favour of recommending the publication of an annual research report prepared by the CACCR. The first such report was published in the September, 1964, issue of the C.I.M. Bulletin; the second appeared in the November, 1965, issue of the same publication."

Jan 1, 1966

"Shales play a major role in the stability of slopes, both natural and engineered. This paper attempts to provide a review of the state-of-the-art in shale slope stability. The complexities of shale terminology and classification are first reviewed followed by a brief discussion of the important physical and mechanical properties of relevance to shale slope stability. The varied mechanisms of shale slope stability are outlined and their importance highlighted by reference to international shale slope failures. Stability analysis and modelling of anisotropic rock slope masses are briefly discussed and the potential role of brittle rock fracture and damage highlighted. A short review of shale slopes in open pits is presented.INTRODUCTIONShales have been stated to form approximately 58% of sedimentary rock so it is not surprising that they are frequently encountered in both natural and engineered slopes. They represent challenging environments for slope stability due to the wide variation in their engineering properties, their changing behaviour with time due to geomorphic processes and the variation in the failure mechanisms as a function of both stratigraphy and tectonics. An extensive body of literature exists on the terminology and classification relevant to shales; it is not possible in the scope and length of the current paper to review these works in detail and the reader is referred to Farrokhrouz and Asef (2013), Bell (2000) and Goodman (1993) for detailed discussions. It is arguably the case that no universally accepted classification of shales exists today and depending on the field of application the terminology varies widely. Shales in slope stability, for the purpose of this keynote paper, are taken to include material varying in properties from weak rocks to soils and therein lies one of the most challenging aspects in shale slope characterisation for engineering purposes. They have been classified as “rock-like” or “soil-like’, (Underwood 1967) or compacted and cemented, Table 1, Yagiz (2001). Classifications have considered numerous factors including composition, cementation and a wide range of engineering properties.The propensity of shales to degrade with time due to geomorphic processes has resulted in an important aspect in their classification, that is, the attempts to incorporate slaking, durability and swelling and softening behavior through purpose developed testing methods (Gamble 1971, Morgenstern and Eigenbrod, 1974). Figures 1 and 2 show examples of terminology used to describe argillaceous materials and some proposed engineering classification schemes (Grainger 1984 and Bott 1986). Corominas (2014) provides a recent classification of argillaceous rocks and their durability relating five stages of slope deterioration to the texture of the rock on Ternary diagrams. No attempt will be made here to discuss the merits of the proposed terminology and classifications, suffice it to say, that the controversy and flux surrounding these issues is a strong indicator of the complexities in the behavior of these materials. In this paper the author will consider slope stability in the materials indicated in Table 1, Figures 1 and 2 without undue focus on terminology. At the lower strength limit of shales the engineer must design slopes using the principles of soil mechanics which may vary from the simple Mohr Coulomb plasticity constitutive criterion to modified critical state models, some even attempting to incorporate softening behaviour in the weaker clay shale materials. Given the transitional nature of shale materials several workers have treated overconsolidated clays and clay shales using concepts such as peak and residual shear strength, brittleness index and softening. Martin and Stacey (2013) provide a useful review of the importance of weak rocks in open pit mining, with mudrocks as a specific member, and note the importance of delayed failure, progressive failure and loosening in the stability of"

Jan 1, 2015

By Ivan Malinsky, Gérard Castonguay

"On a développé un procédé qui donne une fonte (2,3% C, 0,07% V) du V2O5 (99%) et un rutile synthétique (94% TiO2) à partir d'un minerai, dont les réserves au Québec sont importantes. Le procédé comprend les opérations suivantes: 1) la concentration magnétique du minerai (30% Fe, 9% TiO2 et 0,65% V2O5) pour produire un concentré (65% Fe, 7% TiO2 et 1,6% V2O5); 2) le smeltage du concentré aggloméré dans un four à arc, sans fondant, pour produire une fonte et une scorie (30% FeO, 40% TiO2 et 8,0% V2O5) qui contient plus de 95% du vanadium et du titane présents dans le concentré; 3) le grillage alcalin (37% Na2CO3) de la scorie suivi d'une lixiviation à l'eau et de la précipitation de l'hexavanadate d'ammonium à partir du filtrat; 4) la lixiviation du résidu par l'acide sulfurique pur ou usagé pour produire un rutile synthétique. Un estimé préliminaire de la valeur économique du projet laisse croire à sa rentabilité à la condition que l'investissement pour le smeltage soit inférieur à environ 400$/tonne de fer.IntroductionLes gisements de magnétites titanifères sont nombreux dans le monde. Ils consistent en une magnétite étroitement liée a l'ilménite, La teneur trop élevée en TiO2 empêche l'exploitation de ces gisements pour la production de fer. Cependant, dans certains cas, la magnétite a une teneur intéressante en vanadium qui peut rendre l'exploitation de ces gisements rentable. Aujourd'hui, les magnétites titanifères constituent la plus importante source de production de vanadium. On estime qu'environ 70% du vanadium produit provient de ces sources."

Jan 1, 1983

By X. S. Fan, T. R. Feng, D. Chen

To meet the flotation process requirements, the large-scale flotation cell must be designed for sufficient pulp mixing, reasonable air dispersion and solid suspension, which is very difficult to design for super large-scale flotation cell. Hence, the flotation cell scale-up and optimization for a short period is a challenge for super large-scale flotation cell design. Computational fluid dynamics simulation has been applied in flotation cell study, which is effective, timesaving and low cost in the study of the flow field distribution for super large-scale flotation cell. This paper demonstrates the flow field characteristics in the 600m3 flotation cell by CFD. The flotation cell model is meshed with hexahedral grid and the high mesh quality assures the computational precision. MRF model, namely a steady-state approximation, ensures that individual cell zones can be assigned different rotational speed. Euler-Euler approach is chosen for multiphase flow simulation to treat different phases as interpenetrating continua. Numerical simulation of single phase, two-phase and three-phase are investigated respectively. Results suggested that the flotation cell has the apparent upper and lower flow circulation. In condition of the impeller rotation, the air is dispersed reasonably. In addition, the solid phase volume concentration distribution in the cell has a little difference.

Jan 1, 2015

By A. R. Sorta, D. C. Sego

ABSTRACT The settling, shear strength, and index properties of oil sands fines-sand mixture tailings (FSMT) for a wide range of solids and fines content are investigated. Results indicate that the liquid limit of FSMT obeys a linear mixture law. The fines-water ratio (FWR) governs the permeability of composite tailings (CT) and CT with comparable geotechnical behaviour can be produced from the same initial FWR mixtures. A phosphogypsum (PG) dosage > 900 mg/kg does not improve the dewatering behaviour of CT. The undrained shear strength of FSMT at the liquid limit is approximately 2.4 kPa, but is dependent on fines content at the plastic limit.

Jan 1, 2013

By W. B. Timm

Introduction In preparing this paper on Recent Developments in Gold Milling Practice, the idea occurred to me that possibly the best way to deal with the subject would be to take you in thought on a visit to the principal gold mining camps of the Dominion, starting at the east and finishing up in the west, and noting, as we go, the outstanding improvements that have been made in the last few years in the practice of gold milling. Before beginning this tour, I desire to emphasize the debt this country, and particularly our mining industry, owes to that body of trained and experienced men, little heard of, but who, working quietly on their problems, are responsible for these improvements. The metallurgists, to whom I refer, have solved many difficult problems for the mining industry, in connection with the treatment of our complex ores; for instance, the silver-cobalt ores of the Cobalt district, the gold ores of the Porcupine district, the gold-telluride ores of the Kirkland Lake? district, the copper-gold ores of Noranda, the arsenical-gold ores of the Beattie mine, the copper-zinc ores of Flin Flon, and the lead-zinc ores of Kimberley. In doing so, they have maintained the high technical standards of the profession, and the practices thus evolved are noteworthy for their high degree of efficiency. When the price of gold increased from $20.67 to $35.00 an ounce, what had formerly been thought to be a low tailing became almost an ore, so that the metallurgists are now busily engaged upon the problem of putting this railing back in its proper place of being a tailing once more, or from its value, at the present price, of anywhere from 50 cents to a dollar or so per ton, to a few cents per ton. Owing to the changing prices of the metals in the world's markets, still greater improvements in metallurgical practices are imperative. An important contributory factor towards improvement in ore dressing is the aid furnished by the microscope in the examination of ores and mill products. By making possible the determination of the mineral constituents of the ore, their association, and grain size, it gives the investigator a knowledge of his problem, before he does any actual test work. In the Mines Branch laboratories at Ottawa, its use has enabled us to predict how an ore should respond to various methods of treatment.

Jan 1, 1935

By Jie Deng, Wenliang Xiong, Binyan Chen

"With falling rare earth metal prices, low cost beneficiation of rare earth minerals is essential. The “Flotation-Agglomeration-Magnetic” (FAM) separation process is a newly developed technology by IMUMR to economically recover rare earth elements from different types of deposits. The theory of FAM process is to selectively agglomerate rare earth particles and separate from gangue minerals by bubble flotation process. The flotation product is further upgraded by magnetic separation. The FAM process has been successfully applied in industrial production on the Dalucao rare earth ore, Sichuan, China. The average REO grade of rare earth concentrate is 65% in the latest 12 month production run, with an average recovery of 55%.INTRODUCTIONRare earth elements (REEs) include fifteen lanthanide elements coupled with two chemically similar elements (yttrium and scandium). These elements are split into two sub-groups, La to Sm are classified as light rare earth elements (LREEs) and the remaining elements including yttrium are heavy rare earth elements (HREEs) (Kumari & Panda, 2015). The demand of rare earth elements surged in recent years due to their increasing usage in diverse industrial aspects including high strength magnets, phosphors, clean energy, polishing compounds and catalysts (Goley &Scott, 2014).More than 250 REE-bearing minerals have been discovered, but many minerals are with very low concentrations of REEs, varying from 10-300 ppm (Adam &Ping, 2013). The most common rare earth minerals mined are bastnaesite, monazite, xenotime and ion-adoption REE (Chelgani & Rudolph, 2015; Kanazawa & Kamitani, 2006). Before the 1960s, most rare earth resources were extracted from monazite in the beach placer, with the exploiting of Mountain Pass in the United States and Bayan Obo mine in China, bastnaesite became the chief mineral source of rare earth resources (Klinger, 2015). These minerals are commonly separated with gangue minerals by froth flotation, gravity concentration, magnetic separation, or any combination thereof based on their specific physical characteristics (Zhou & Wang, 2014; Adam & Richard, 2014; Yang & Satur, 2015; Xia & Brian, 2015a,b)."

Jan 1, 2016

By J. S. DeLury

The last few years have been eventful ones for Manitoba in connection with mineral development. Perhaps the past year has been the most important of all. It is therefore a suitable time to review the mining situation in the Province. In order to obtain, in the following paper, a proper set ting from which to discuss the trend of recent developments, a brief review of the story of mining will first be given. This will include a summary of a few of the outstanding facts regarding prospecting, discovery, and operations in the several known metalliferous areas of the Province. Following this will come a more detailed description of activities during the past year or two. Special attention will then be paid to the outstanding enterprises, such a~ those associated with the names of Flin Flon, Sherritt-Gordon, and Central Manitoba, names which have been attracting the attention of the mining world to Manitoba. And last of all will be presented a brief summary of mineral production, which, so far, has largely been credited to non-metallics. HISTORICAL To aid a proper comprehension of the recent trend in mining, it is well not to lose sight of the history of development in the different metalliferous areas in Manitoba. This Province seems throughout to have been more or less dependent on mining interest excited by discoveries in the neighbouring province of Ontario. The first interest came as an effect of the Lake of the Woods mining boom, when small adjacent parts of Manitoba were prospected. Several discoveries were made, but no mining industry resulted.

Jan 1, 1929

By J. E. Hawley

"The Aldermac copper deposit is in Beauchastel township, Abitibi county, Quebec. It lies about 11 miles west of Noranda. It has been described by Cooke, James, and Mawdsley(2) and by Bruce(3) and has been mapped in detail by W. Samuel and the late K. W. Fritzsche, former Mine Geologist, and by J . E. Gill and A. R. Byers, so that most of the particulars contained in the description that follows are largely the result of the work of others than the writer, whose connection with the deposit, in a consulting capacity, extended over the last 5 years of the life of the mine.According to A. V. Corlett, former Mine Manager, the property was staked during the early winter months of 1923 because of its location adjacent to the syenite intrusive that had been mapped by Cooke near the height-of-land in this township. An examination by Mr. Corlett in 1924 revealed mineralized zones to the north of MacKay lake, and in the vicinity of these K. W. Fritzsche, by dip needle and trenching, discovered the No. 1 and No. 2 deposits, which were both too small and too low grade for exploitation. During the winter of 1925, A. A. MacKay, with a dip needle, picked up a magnetic 'anomaly' in a drift-covered area about 600 feet to the north of previous workings. Trenching here revealed only a narrow zone of mineralization of little consequence, but, farther east, MacKay discovered a more pronounced 'anomaly' over what later drilling and underground work proved to be ore of commercial grade (No. 3 and No. 4 orebodies)."

Jan 1, 1954

By R. D. Lawrence

"Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of general accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.INTRODUCTIONGreat strides have been made recently in achieving an international consensus on mineral reserve and resource definitions and classifications. The Australasian JORC code, the CIM code in Canada, the SME proposal in the United States and even a proposed code from the United Nations have all brought the objective within reach.Unfortunately, this success has led to another problem for mineral valuators. Certain securities regulators, tax collectors and their ilk have begun to expound on the opinion that discounted cash flow projections carried out to calculate net present values that would form the basis for a valuation determination should be based solely on proven and probable reserves. The author disagrees with this position. This paper examines the subject from four points of view:"

Jan 1, 2003

By C. R. Whittemore

PROGRESSIVE industrial organizations have recognized the importance of maintaining an adequate reference library of volumes covering all phases of their particular branch of industry, but it has been the experience of the writer that few engineers know how to use to the best advantage this store of extremely -valuable information which has been accumulated for their service. Nor does the average engineer appreciate the fact that it is only through the current technical literature that he can keep abreast of the rapidly developing fields of engineering. The present-day ramifications of the engineering field are of such wide scope that the human mind is not capable of storing away more than a small fraction of the information available on any particular topie; yet, from time ? to time, such information would prove invaluable. An engineer can know intimately only a small part of his own branch of engineering; but he cannot afford to neglect to take the fullest possible advantage of all that is already known in his own particular field. Technical information may be obtained by one or more of the following methods: (1) by enquiring of the individual who knows; (2) by performing the experimental investigations necessary to ascertain the facts; (3) by consulting the technical literature, where a record may be found of the work of others. This last method is the one we wish to examine. Our main consideration is the question of how to use the library, but first it is necessary to give some attention to the kind of enquiries one takes to the library, and to the nature of the sources of information available.

Jan 1, 1938

By H. M. Kim, J. Rutqvist, D. W. Ryu

"Demand of high pressurized gas storage in underground rock caverns is increasing. Compressed natural gas (CNG) and compressed air energy storage (CAES) are one of the promising examples after since lined rock cavern (LRC) concept has been verified through in-situ pilot tests. Two key essential concerns of high pressured gas storage in underground rock caverns are mechanical stability of the cavern against high inner storage pressure and the risk of gas leakage from the caverns.In this study, we introduce our results of numerical simulations so as to investigate the potential of monitoring for gas leakage at a pilot facility for CAES in underground LRCs. The pilot facility was constructed at a comparatively shallow depth of 100 m, compared to the previous cases with several hundreds of meters, aiming at validating the feasibility of the LRC storage concept in which inner sealing liners, consisting of steel plate and concrete linings, are installed inside the excavated rock caverns (KIGAM, 2011). Compressed air may leak through either initial defects of inner containment liners such as imperfect welding regions and in-situ construction joints of the liners, or through structurally damaged points of the liners during the CAES operation where compression and decompression of the caverns are necessarily repeated and their structural robustness can be deteriorated.For this perspective, we carried out a coupled thermodynamic and geomechanical deformation analysis using TOUGH-FLAC simulator, and investigated the effectiveness of strain monitoring method in detecting mechanical failure of liners which may provide major pathways of air leakage. We therefore used an equivalent continuum model to relate the localized tangential strain to fracture permeability changes, which was developed in our early work (Rutqvist et al, 2012). In detecting and characterizing the leakage location, we tested a cross correlation technique using the synthetic pressure responses monitored in case of the failure of the inner liners. From the investigations, we showed that tangential strain, rather than radial, monitoring especially at the inner face of the sealing liners can be more effective in detecting the mechanical failure of the liners.In localizing the leakage point, we noted that the interface between the inner liners and surrounding rock may not be perfectly bonded so as to increase permeability through which any leaking air pressure may migrate more dominantly. We also demonstrated that the cross correlation of the time histories of pressure measurement especially at these interfaces can be useful in identifying the leakage point. These results may provide useful information in overall design of monitoring and alarming system of our upcoming CAES pilot facilities."

Jan 1, 2015

By A. F. Matheson

The St. John Del Rey Mining Company, Limited, is an English company owning 150 square miles -of mining lands near Belo Horizonte, Minas Geraes, Brazil. The area is 2,300 to 5,000 feet above sea level, with a pleasant and healthy climate. Bedrock is Precambrian. The Nova Lima series of metamorphosed sediments and some volcanics is overlain uncomfortably by the Minas series of quartzites, itabirites. etc. Batholithic granite and gneiss cut both series and basic dykes cut all these rocks. There are important deposits of gold, iron, and manganese on the Company's holdings, as well as occurrences of arsenic, antimony, cobalt, nickel, dolomite, day, quartz, -ochre, bauxite, kyanite, and asbestos. Except for gold and consequent recovery of arsenic, all the other materials are relatively unexploited. The Company operates the Morro Velho gold mine and the Espirito Santo and Raposos gold mine. The Morro Velho mine was purchased in 1834 for £56,000. To the end of 1952 it had produced 7,000,000 troy ounces of gold from 15,000,000 short tons of ore. The ore z?ones are replacement deposits in a sinuous siliceous dolomitic rock locally termed "lapa seca," and plunge east, near surface at 45 °, at 8,000 feet at 15°. The ore minerals are pyrrhotite, arsenopyrite, pyrite, and chalcopyrite. Gold is finely distributed and almost nowhere visible. Ore reserves at the end of 1952 were estimated at 5.5 million short tons grading 0.39 oz. gold per ton. Chances exist for new ore within the mine area. The Espirito Santo and Reposos mine, in folded banded iron formation, has mineralization similar to Morro Velho but sulphides are less abundant. The mine to a depth of 2,500 feet has estimated ore reserves of 1.5 million tons of an average grade of 0.28 oz. gold per ton. New ore may be expected both laterally and at depth. To the end -of 1952, the ?Company had paid dividends of almost £4,- 600,000, largely earned from the operation of the gold mines.

Jan 1, 1956

By Ralph V. Stewart

"The asbestos orebody is contained within ultrabasic rocks of Precambrian age, being located in the continuous permafrost zone of the Quebec Ungava Peninsula, some 300 miles north of the tree line at approximate latitude 61'49' and longitude 73°58'.The asbestos deposit is at the western tip of a folded ultrabasic sill complex which trends northeast and covers an elliptical area 4.5 miles wide by 15 miles long. Locally. the asbestos occurs in. a completely serpentinized dunite rock. The principal rock types in the vicinity of the ore-body originally consisted of dunite, peridotite and pyroxenite, all of which have experienced at least two periods of alteration, so that no fresh rock now remains.The main ore zone in the open pit is approximately one quarter mile in length, 150 to 200 feet in width, and plunges at 25 to 30 degrees in a northeast direction below surface, to a vertical depth of at least 1,200 feet, Consider¬able tectonic activity resulted in favourable structural conditions which culminated in the formation of the ore zone in its present form.The deposit consists principally of cross-fibre ""gash type"" veins which vary in length from several inches to several feet. The principal fibre vein direction is parallel to the dip of the enclosing serpentinized dunite and sill complex.Some of the problems encountered during diamond drill¬ing in permafrost are briefly discussed."

Jan 1, 1976

By K. Mayhew, R. Bruce, A. Heidel, G. P. Demopoulos

"Teck and Aurubis are working together to commercialize a technology for the processing of copper arsenic sulphide concentrates that is economic and sustainable with regards to the environment and community. The pressure hydrometallurgical approach is a desirable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. A test work program was carried out where a range of copper concentrates with varying arsenic grades was processed under CESL leach conditions. This paper discusses the stability character (in terms of arsenic) of the resulting residues and their mineralogy. The basic ferric arsenate sulphate phase (BFAS; otherwise known as type 2) was identified as the main arsenic carrier. All CESL residues demonstrated high stability (<1 mg/L As) through a range of aggressive (pH and ORP) environmental leach conditions.INTRODUCTIONArsenic deportment and control in the copper industry needs an integrated approach involving each stage of the value chain, i.e. exploration, mine operation, refining process and mine closure. Teck Resources Limited (Teck), Canada’s largest diversified mining company and Aurubis, Europe’s largest copper producer, have formed a partnership to advance the application of CESL copper-gold technology for the development of high arsenic bearing copper resources (Bruce et al., 2011).Among the options for arsenic control in the metallurgical treatment of copper concentrates is the precipitation of ferric arsenate, which is widely accepted as the most suitable method for stabilizing arsenic (Ferron and Wang, 2003). The pressure hydrometallurgical approach to processing arsenic bearing copper concentrates is a favorable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. Under CESL pressure leaching conditions (150 °C, 1380 kPa) high copper extraction and arsenic (V) fixation is possible.Within the pressure leach autoclave, arsenate and ferric iron react to form scorodite type phases. The precipitate formed under CESL conditions is dependent on the Fe (III) /As (V) ratio and the tenor of cations and anions, particularly excess sulphate (Gomez et al., 2011a). Previous studies on CESL residues have found arsenic to be present as crystalline scorodite (FeAsO4.2H2O) (Bruce et al., 2011), basic ferric arsenate sulphate (BFAS: Fe(AsO4)1-x(SO4)x(OH)x·(1-x)H2O, where 0.3<x<0.7), and/or arsenate adsorbed on to hematite (Gomez et al. 2011b). Although not a focus of previous work, scorodite was the predominant precipitate formed when the concentrate Fe/As was <1.5 (Mayhew et al., 2010), and BFAS was the predominant precipitate when the concentrate Fe/As was >10 (Gomez et al. 2011b)."

Jan 1, 2012

By H. C. Gunning

Introduction The invitation to contribute a discussion on some of the broader features of the mineral deposits of our Cordillera seemed acceptable enough when presented several months ago. More mature consideration has impressed upon me the difficulty of making any constructive or very helpful contribution in the short time available and with my limited inspiration. Dr. Lang deserves our real gratitude for his general paper of nineteen pages at the beginning of the Volume. Into it, with the help of two diagrams and seven tabular summaries, he has packed a lot of useful information and has analyzed along several lines the data of the Volume&apos;s twenty-eight detailed papers on our mines and camps. He has added additional facts from his own knowledge of the region. I am sure that, like myself and the whole fraternity, he feels especially grateful to the eleven company geologists who found time to contribute detailed descriptions of mines they have studied. The Regional Situation With the Jubilee Volume and two recent publications of great value from the Geological Survey, we are more up-to-date on Cordilleran geology than we have ever been. But I would like to emphasize that we still have but fragmentary information. Brief study of G.S.C. Map 932A will illustrate this. Our knowledge of the Rocky mountains is limited to two narrow sections along the main railway lines, a somewhat larger area from the border north along the Mesozoic coal-bearing basins, and some reconnaissance along Peace river and the Alaska highway. There is some additional information on old maps, particularly those by G. M. Dawson, but it is very much of the &apos;exploratory&apos; type. The other mapped areas are chiefly in the accessible region south of &apos;fifty-one&apos;, in the central part adjacent to and spreading north, recently, from the Canadian National railway, and along the edges of the Coast Range.

Jan 1, 1950

By Robert K. Jonas

Mining companies can improve production and reduce costs by using the best available technology to control their operations. Many mines are challenged to use multivariable predictive control due to limited experience or staffing, as well as being concerned over the robustness and sustainability of predictive controls. As a result many mines are not realizing optimal performance from their assets, and thusly are not realizing the production increases or cost reductions that this technology can deliver. Over the past few years, the application of multivariable model-based predictive control has gained acceptance in many mining processes and has proven to be robust and sustainable for some of the most challenging mining processes. New automated modeling and performance monitoring software have greatly simplified the effort to implement and maintain these solutions. In addition, many progressive companies have chosen to co-source the implementation and service of these solutions to assure project success and continued benefits stream. This technology has been successfully applied to a wide variety of processes; grinding mills, alumina digestion, CCD washer and thickeners, kilns, calciners, roasters, flash smelters, heat exchangers, evaporators, and most recently in the demanding process of flotation. This paper discusses the state-of-the art in advance control technologies in the mining industry, including the impact of these technologies on maximizing benefits, and implementing best practices for long term sustainability. Benefits from recent multivariable predictive control applications in copper mining will be reviewed, and the use of the latest predictive control technologies and practices in mining will be discussed.

Oct 1, 2009