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By K. G. Davies, M. J. Royea

"A major program of pillar recovery at the Sullivan mine has been assisted for the past several years by a concerted series of rock mechanics investigations. The object of these investigations is to measure the parameters of rock behaviour which influence pillar mining. This quantitative information is then used in the design of mining methods appropriate for various conditions.Instrumentation to measure absolute rock stress, changes in rock stress and the gross deformation of rock masses has been developed. Various instruments are described, as are instrument evaluation procedures and typical test results. The data from underground measurement projects have been used to modify pillar extraction sequences along re-treat fronts. Rock mechanics information from individual pillars has been incorporated into the design of mining methods to suit particular circumstances."

Jan 1, 1968

By H. W. Smith, D. Guerin

"This paper describes the development of a dynamic model for a full- scale (64 tonnes/hr) grinding circuit consisting of an open-circuit rod mill feeding a ball mill operating in closed circuit. The object of constructing such a model is to investigate the static and dynamic behaviour of potential control schemes. Model selection, data processing and parameter estimation are discussed, and static and dynamic results of simulations are presented. Conclusions are drawn with regard to the adequacy of the model for such studies, and likely limitations on control of such circuits.IntroductionThe model developed here is intended to represent the grinding behaviour of the grinding circuit at the Lake Dufault division of Falconbridge Copper Mines Ltd. This circuit has been fully described elsewhere. At the time of the work described, the ball mill discharge was fed to a four-cell flotation bank , the tailings of which are combined with the rod mill discharge in the cyclone feed pump sump. As the emphasis in this study is on grinding behaviour, and as only I per cent of cyclone feed material is removed in these cells, no attempt has been made to include flotation behaviour in the simulation. One effect of the presence of flotation cells in the grinding circuit is, however, to necessitate somewhat finer grinding than might otherwise be needed: this will have effects on mill parameters.The paper is organized as follows. First the selection of models is discussed, paying particular attention to the problem of selecting simple, yet adequate, flow models for the mills. Then data gathering is described. The method of deriving mill model parameters is explained, and the results presented. Mass balancing of cyclone data and the determination of cyclone model parameters are described. The linking of the models into a full simulation is outlined, and sta tic and dynamic results presented. Finally, the results are discussed and conclusions drawn ."

Jan 1, 1980

By G. C. Hodgson

Specification and Tests of Rope Wire Chemical Analysis: The range in composition of steel used in the manufacture of wire rope is as follows: Carbon 0 4 to 0.9 per cent Manganese 0 4 to 0.8 Sulphur Not above 0.04 Phosphorus Not above 0.04 The carbon and manganese content are varied according to the gauge of wire to be drawn and the tensile strength required. Generally speaking, best results are obtained from heats where the melt is not of too large a tonnage. The amount of reduction and patenting of the wire is left to the wire maker, who thus has a free hand in meeting the balance of the specification.

Jan 1, 1931

By J. B. Heslop, D. S. Bubar

"The Gondor Zn-Ag-Pb-Cu deposit is a stratabound massive sulphide lens occurring within Archean volcaniclastic rocks of the Yellowknife Supergroup. The deposit is located in the west-central portion of the Slave Structural Province, approximately 350 km north of Yellowknife.Initial diamond drilling at Gondor has outlined a steeply dipping, L-shaped, folded, massive sulphide body, which may be traced over a strike length of approximately 800 m, and to a depth of 350 m. True widths of up to 40 m have been intersected in the thickest part of the deposit. Preliminary estimates suggest that the deposit contains a minimum of 7.5 million tonnes grading 6% Zn, 50 g/tonne Ag and less than I% combined Cu and Pb. In addition, significant gold, grading up to 2.8 g/tonne, occurs in some parts of the deposit. The mineralization is open both down-dip and along strike.The Gondor deposit lies conformably within a predominantly east-west striking, north-facing sequence of felsic to intermediate volcaniclastic rocks. Coarse fragmental rocks are abundant in the hanging wall, whereas ash and lapilli-tuffs predominate in the footwall. The main structural feature in the area is a large-scale, steeply northeast-plunging, Z-shaped fold. The sulphide mineralization lies within the synformal portion of this fold, with the thickest part of the deposit coinciding with its hinge zone. Several episodes of faulting have also affected the local stratigraphy.The wallrocks of the Gondor deposit were hydrothermally altered prior to the onset of medium-grade regional metamorphism. A halo of altered rocks surrounds the massive sulphide lens, with no apparent difference in the degree of alteration between the hanging wall and footwall strata. The alteration zone is characterized by the addition of MgO and K20 and by the depletion of Na20 and CaO. These changes are reflected in the mineralogy of the altered wallrocks by local enrichment in chlorite, biotite, muscovite and cordierite.The mineralized zone is medium- to coarse-grained, well-banded and is composed largely of pyrite, quartz, and sphalerite with subordinate galena and chalcopyrite. Preliminary studies of metal distribution indicate that a lateral zonation is present, with lead enrichment in the central part of the deposit, and copper enrichment toward both ends. Stringer-type copper mineralization has not yet been discovered in the footwall of the Gondor deposit."

Jan 1, 1985

By D. W. McDonald

Coal mining and railway transportation are so closely en-twined and so dependent one upon the other that the failure of one would mean the total collapse of the other. With this indisputable fact in mind, there is no doubt that the operator of each is deeply interested in the other's success. Railway transportation began at the mouth of a coal mine. The first railway car was the English coal-wagon, a crude box on four wooden trowlets, running on wooden rails and holding 1,600 pounds. This was operated by gravity or horse-power in England to convey coal from the mines to the rivers. The first coal-cars used on Nova Scotia railways were of 4 tons capacity with side doors and "V" shaped centres. Then followed flat-bottom, 4-ton cars that operated on tipples, the car bei.ng held in tipple by a chain passing over the top and fastened on either side. Next came the 6-ton car with drop-bottoms, then the 10, 15, 30-ton cars, and now the modern 50 and 100-ton steel cars, equipped with automatic couplers, brakes, and rachet dumping device. Contrast the first coal-car with a modern luxurious pull-man or a I 00-ton coal and ore car, and you have a record of progress in railway transportation. The development of the steam locomotive was no doubt the greatest factor in this progress, but let us not forget that the foundation of all industrial development was and is coal. and that development in mining and railway transportation should keep abreast.

Jan 1, 1924

By Gregg W. Morrison

"The Craigmont copper-iron skarn deposit is adjacent to the southern margin of the late Triassic Guichon Creek batholith in south-central British Columbia. Host to the ore are sedimentary and volcanic rocks of the western calc-alkaline belt of the Upper TriassicNicola Group. In the mine area, the Nicola Group rocks are a stratigraphically complex sequence, at least 1800 feet thick, which have been subdivided into Basalt, Rhyolite, Carbonate and Clastic Sediment units. All the units strike and dip parallel to the margin of the Guichon Creek batholith and are within the batholith contact aureole. However, only the Clastic Sediment unit is in contact with the batholith.Most of the skarn and ore is within the Carbonate unit and more specifically within an Interbedded facies that consists of lime sandstone, lime siltstone, quartzo-feldspathic siltstone and argillite. The Interbedded facies and the adjacent barren Massive Limestonefacies are interpreted aspart ofa carbonate reef complex. The distribution of skarn and ore within the Interbedded facies suggests that the facies boundary was a physical and chemical barrier that resulted in concentration of metals adjacent to the Massive Limestone facies.Two stages of skarn formation have been recognized at Craigmont. In Stage I, ore-bearing magnetite-rich and actinolite-epidote-magnetite skarns developed both in basaltic rocks and in Fe-bearing siltstone and argillite of the Interbedded facies, while barren grossular garnet-epidote-calcite-pyrite skarns developed in Fe-poor rhyolitic bands within the Interbedded and Massive Limestone facies . In Stage ll, massive, barren grandite garnet skarn replaced mineralized Stage I skarns in the vicinity of diorite plugs. and specularite ore formed in brecciated Stage I skarn and clastic rocks away from the plugs. Theformation of Stage I skarns required no addition of material, only redistribution and concentration of elements already present within the Interbedded facies. However, the concentration of Cu in Stage lore requires a mechanism for more efficient leaching of Cu from the host rocks, an anomalous concentration of Cu at the site of the Stage I orebody or an additional input of Cu from an external source. The formation of Stage II skarn and ore requires only remobilization and recrystallization of Stage I skarn and ore.Copper and iron are the only elements in economic concentrations in the ore and chalcopyrite is the only significant copper-bearing mineral. Chalcopyrite is disseminated and interstitial to magnetite in Stage I mineralized skarns and is interstitial to specularite in the matrix of Stage II breccia ores. Chalcopyrite also occurs with pyrite as stringer ore in bleached • sediments and rhyolite tuffs in the stratigraphic footwall of the main orebodies.The Craigmont deposit has more features in common with Cu-Fe deposits hosted in metavolcanic and metasedimentary rocks than it has with typical skarn deposits associated with porphyry copper deposits. The orebody is more likely a product of concentration of metal contained within the Nicola Group rocks than of the mineralizing event that produced the . Highland Valley Cu-Mo porphyry deposits in the central part of the Guichon Creek batholith ."

Jan 1, 1980

By L. Yacher

Most metallurgical plants already have sophisticated control systems as well as a process-historian that manage thousands of real-time and historical variables. There exists a huge potential for operational improvement through the inference of patterns, correlations and cause-effect relationships within these records. The ability to run online and offline advanced multivariate statistical analyses represents a great potential for the mining industry, in various areas such as cathode quality improvement in an SX/EX plant, the analysis of the correlation between the ore characteristics and the mill throughput, the determination of early failure alerts for major equipment, etc. The background theory is described, as well as some practical experiences of operations in Chile and Peru. Cu2007

Jan 1, 2007

By R. Dawes, B. R. Davis, T. LeBel, C. Pelow

Settling of copper, lead, and other metals in slags is an important part of overall recovery of metals, both in primary and secondary operations. The impact of slag reduction on settling is not well known. This is important since the cycle time for slag cleaning can be significantly changed with reduction of slag, through a decrease in slag viscosity and growth of metal/sulphide particles. KPM has worked with a number of primary and secondary recyclers to better understand how reduction of slag can improve overall operation. In this presentation, we describe the type of test work and analysis done and how this information can be used to guide improvements in metal recovery from slags. INTRODUCTION Typically, copper smelter slags contain about 1-2% copper, both in the form of copper and copper sulphide beads and dissolved copper oxide in the slag (converter slags are recycled to the smelter). With the average grade of world copper deposits close to 0.7%, it is practical to recovery copper from these slags. This is done routinely by one of two methods. The first method uses slow cooling in large ladles or beds to grow particles of copper sulphide. The slag is then crushed, milled, and floated for copper recovery. The slow cooling promotes precipitation and growing of the sulphide particles from the solution and then, the slag can then be milled to recover the copper through froth flotation. A consideration of this process includes the energy cost related to grinding, the use of water, capital cost for ladles, and the availability of tailing dumps. At the same time, the retreatment of the Cu concentrate produced in the mill will displace fresh concentrate, which ultimately results in a reduction of the throughput. The second method is the so-called “slag cleaning” and is based on the settling of copper and copper sulphides particles dispersed in the slag. This is achieved by decreasing its viscosity by increasing the slag temperature and reducing the iron spinel solid phases (magnetite) that increase the apparent viscosity of the slag. Typically, the reduction does not extend to the reduction of copper, and soluble copper (mainly as oxide) and fine matte particles remain at concentrations typically at or above 0.5% (Cardona et al., 2011; Cardona, 2011). This is an improvement on 20 years ago when slag was sent to dumps at 1% or less (Demetrio et al., 2000).

Jan 1, 2019

By M. P. Amsden

"Ecstall Mining Limited, a subsidiary of Texasgulf, Inc., Operates the Kidd Creek Mine, Concentrator and Zinc Plant at Timmins, Ontario. Two different ore types are mined and milled to produce concentrates of copper, zinc, lead and tin. The ores are processed at the Concentrator in three separate individual milling circuits, each with the capacity to treat up to 3500 tons per day. Two circuits treat copper-zinc ore 1t an average combined rate of 6500 tons per day and the third circuit treats 3500 tons per day of silver-lead zinc ore. Conventional crushing, grinding and flotation procedures are followed. The purpose of this paper is to describe Ecstall's experience with rubber mill linings in the grinding circuits.CrushingBoth ores are crushed to minus 6 inches at the Mine and delivered by rail to the Concentrator where they are reduced by secondary and tertiary crushing to minus 5/8 inch.GrindingThe crushed ores are prepared for selective flotation by grinding with rod mills and two stages of ball milling. flotation circuit middling products are reground in regrind mills prior to further treatment. A typical flowsheet of one of the grinding circuits is shown in Figure 1.All the grinding units are Allis-Chalmers Mills. The rod mills are 10 1/2 feet diameter by 16 feet long. Both the primary and secondary ball mills are 12 feet diameter by 18 feet long and all regrind mills are 6 feet diameter by 12 feet long. The primary mills are charged with 1 13/16 inch forged balls. Secondary mills are charged with 1 1/2 inch forged balls and the regrind mills are charged with 1 inch forged balls. All cyclones are Kreb units. The primary cyclones are Dl5B hydrocyclones, the secondary cyclones are D6B hydrocyclones and all regrind cyclones are D6B hydrocyclones."

Jan 1, 1974

By R. Plassart, F. Laigle

"As a powerhouse, a transformer or a valve chamber, large underground caverns are a major element of hydropower plant. On the contrary to galleries and shafts which are linear and long underground structures, large caverns are designed with often complex geometries and large spans. Moreover, as these caverns are generally located on the foot of the hydraulic scheme, the high overburden is often responsible of a high stress state. Thanks to current experiences in France and around the world, the Hydro Engineering Centre (CIH) of EDF has defined great principles in the design of caverns leading to a more general methodology. The project of Tehri in India is an example of difficult ground, with in the same time a high overburden, a ductile material and an important schistosity. These physical realities are attempted to be approached in numerical modelling thanks to a constitutive law with softening behaviour and an oriented criterion integrated in the continuum model. As a result, a flexible support is advised, based on a high density bolt system and a thin lay of shotcrete. This methodology has been developed in the case of Gilboa in Israel, except the schistosity which has not been observed in situ. At last, the example of Gavet (France) illustrates a discontinuous case of numerical modelling for a good quality but fractured rock mass.PRINCIPES ET METHODES DE CONCEPTION DE GRANDES CAVERNESHYDROELECTRIQUES SOUTERRAINESRESUME Les grandes cavernes souterraines abritant les turbines, les transformateurs et certaines vannes sont des ouvrages majeurs dans les aménagements hydroélectriques. A la différence des galeries et des puits qui présentent de longs linéaires, les grandes cavernes sont des structures à la géométrie souvent complexe et avec des portées conséquentes. De plus, ces cavernes étant généralement situées en pied du circuit hydraulique, la grande couverture rocheuse peut se traduire par un état de contraintes important. Forte de ses expériences récentes en France et dans le monde, le Centre d’Ingénierie Hydraulique d’EDF a identifié de grands principes de conception des cavernes permettant l’élaboration d’une méthodologie plus générale. Le projet de Tehri en Inde est un exemple de terrain difficile, présentant à la fois une forte couverture, un matériau ductile et une schistosité marquée. Ces réalités physiques sont approchées au mieux grâce à la prise en compte dans les modélisations numériques d’une loi de comportement radoucissante avec un critère orienté intégré dans un modèle continu. Les résultats ont conduit à privilégier un soutènement souple basé sur un boulonnage systématique relativement dense associé à une fine couche de béton projeté. Cette méthodologie a ensuite été reprise pour le projet de Gilboa en Israël, exception faite de la schistosité puisque non observée sur site. L’exemple de Gavet (France) enfin permet d’illustrer un cas de modélisation numérique discontinue d’un massif rocheux de bonne qualité mais fracturé."

Jan 1, 2015

By B. J. McKay, K. Schneider, H. B. Nadendla

"A series of experiments were conducted to assess the impact of zinc additions on the morphology and soundness of the interface of Al-Mg compound castings. It was found that high amounts of zinc (>15wt%) are necessary to affect the morphology and microstructure of the interface. At these zinc concentration levels, the formation of the zinc-rich phases t1 and ? were observed along with the Al-Mg intermetallic phases ß and ?. The micro hardness of all phases across the interface was found to be similar, ~200 Hv. This even hardness gradient is thought to avoid mechanical failure in the interface under load. In samples containing large concentrations of zinc (>15wt%), the formation of bubble shaped voids as well as the complete transformation of the aluminium alloy was observed. While the exact mechanism causing the voids has not been identified it thought to be connected to the Kirkendall effect. INTRODUCTION Conventional single material components are increasingly failing to meet the demands, in terms of cost and performance, of the transport industry. Compound castings have been identified as a promising alternative as they possess a number of benefits (Bührig-Polaczek, Röth, Baumeister, Nowack, & Sussmann, 2006). Compound casting is described as a process in which a metallic melt is cast around a solid metal shape. Preliminary research has concluded that for the stability of such a resultant hybrid structure it is imperative that both metals form a sound connection via form closure, force closure, or material bonding. A continuous material bond between the two metals is also highly desirable as the formation of a crevice between the metals could lead to galvanic corrosion, particular in a humid environment (Lao, 2013; Rübner, Günzl, Körner, & Singer, 2011). Even though Al-Mg compound castings could offer the biggest potential in terms of weight savings to date only a limited amount of research concerning such structures exists."

Jan 1, 2018

By G. M. Proudfoot

IN June, 1940, a .Longyear 3420 blast-hole drill rig was purchased by the Hudson Bay Mining and Smelting Company for the purpose of experimental blast-hole drilling. The early work showed that the diamond drill could compete successfully with the Leyners then in use and by January 1st, 1941, the diamond drills were placed on contract. They may be considered to have gone into production at that date. Prior to the introduction of the diamond drill, our bench drilling was clone with Ingersoll-Rand S-70 and S-83 Leyner drills. Holes up to 40 feet were drilled, using coupled 1 1/4-inch round steel. Bits with a gauge of 3 inches were used in starting these holes, with a drop of 1/8-inch gauge for each 2-foot run. The holes normally ended with 1 1/2 or 1 5/8-inch gauge, though bits down to 1 1/8 inches were available for holes longer than normal or for holes drilled in abnormally abrasive ground. This method of drilling was very satisfactory and was a distinct improvement on the three-bench method of drilling used previously (1). During 1937 and 1938, when experienced miners were available, Leyner long-hole drilling was carried on with great efficiency. However, in 1939 and 1940, labour turnover in-creased and experienced long-hole drillers became scarcer. This resulted in a marked decline in the efficiency of the drilling operations, with increased costs and less tonnage drilled per shift. EXPERIMENTAL WORK The initial diamond drilling test work was carried on with a Longyear 3420 air-driven blast-hole drill rig, drilling a 1 3/16-inch hole. Tests indicated that diamond drilling could be successfully adapted to local conditions and that overall costs compared favourably with costs obtained with the Leyner long-hole method. Leyner long holes on stope benches usually bottomed at a larger diameter than the 1 3/16 -inch diamond-drill holes. More powder could therefore be introduced into the Leyner holes than could be placed in the diamond-drill holes. To achieve the same fragmentation, additional footage was required when diamond drilling. Diamond-drill holes of larger diameter were indicated.

Jan 1, 1943

By Farzad Khodabakhshi, Adrian P. Gerlich

"Multi-pass friction stir processing (FSP) was performed to fabricate a new Al-Mg-Graphene nanocomposite. Microstructural developments and distribution of graphene were studied by using electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM) analysis. In the stirred zone (SZ), grain structure was refined down to about 2 µm attributing to the operative dynamic restoration mechanisms and the locking effect of graphene phase. As a result, the yield strength of Al-Mg alloy was improved more than two times due to incorporation of graphene nano-sheets. Also, the indentation hardness resistance of nanocomposite was increased up to ~60%.INTRODUCTION Aluminum-matrix nanocomposites have garnered significant in recent years due to their superior performance and potential advantages for several industrial applications including the automotive and aerospace sectors. Among various reinforcing nano-materials, carbon-based structures featuring sp2 or sp3 hybridization bonds have been found to offer considerably improved physical and mechanical properties. Such carbon allotropes form at micro- and nano-scales including; graphite, carbon nano-tube (CNT), nano-fiber, and graphene. The potential of two-dimensional (2D) carbon materials was introduced in 2004, with the development of graphene as an alternate 2D allotropic form of the carbon structure with a honey-comb lattice at the atomic-scale. It has been shown that it is currently among the strongest materials ever tested with an intrinsic tensile strength of 130 GPa and Young’s modulus of 1000 GPa, and also offers unique thermal and electrical properties.To fabricate metal-matrix nanocomposites reinforced by graphene nano-sheets with typical metallurgical processing techniques, some attempts have been reported in the literature for various solid-state techniques including; hot rolling, mechanical alloying, and friction stir processing (FSP) of pre-cast plates or surface dispersed graphene oxides. The main challenge in those methods was to facilitate the considerable high temperature and pressure for attaining a uniform dispersion of the nano-sheets during the consolidation process. In most cases, significant difficulties have been reported in obtaining a uniform dispersion of graphene within the metal matrix. Among various techniques for production of metal-matrix nanocomposites, FSP has attracted significant attention as a method of surface modification since it was first reported by Mishra et al. In this process, a non-consumable rotating tool is plunged into the surface of material for the aim of microstructure modification. Extreme material plasticity is induced without melting as a result of friction between the tool and workpiece. Frictional heating and severe plastic deformation induced by the FSP process enables metal matrix nanocomposite fabrication by softening the base material and mechanical stirring to disperse the reinforcing nano-materials into the matrix."

Jan 1, 2017

By W. Basuki, B. Setyotomo, L. Hakim, R. Hendrajaya

Due to high crack sensitivity of slab product of gas and oil line pipe application, its steel making process and alloy composition were evaluated and then improved to overcome its critical solidification process and reduced surface defects. The study was conducted at Slab Steel Plant Krakatau Steel. The purpose was to improve slab surface quality by reducing surface defects so that the slab surface doesn't need to be totally repaired. The method applied was by performing plant trial process, which the secondary process parameters such as alloying method and the casting parameters such as casting powder selection, metallurgical cooling, mould level control, and superheat were continuously monitored and then adjusted to the surface quality of the product. Based on the calculation of Ferrite potential of the steel, the chemical composition was designed to achieve optimum casting parameters in order to avoid high shrinkage during solidification. The results of the study are decreased surface defect quantity, and smooth casting process. The quantity of crack decreased by almost 90%. The slab surface repairing was significantly reduced from 85. % to less than 10%. These new casting parameters and developed alloy composition are then used and standardized for the mass production of the steel.

Jan 1, 2005

By D. W. R. George, J. L. Stewart

Developments in the last decade, which have contributed to increased productivity and decreased coke rates in the iron blast furnace, are reviewed. Future progress in blast-furnace practice is also considered.

Jan 1, 1966

By Jiuhua Xu, Shuiku Jia, Weiren Sun

"The Jinqingding gold deposit, situated in the east Jiaodong Peninsula of Shandong province, is typical of the pyrite-quartz vein gold deposits in the Muping-Rushan gold belt of China. The gold deposit is controlled by a great NNE fracture zone and is composed of several lenticular orebodies within the fracture rone occurring in the Kunyushan granite massif. The Kunyushan granite massif was formed by the replacement of the Archean Jiaodong group.The main minerals associated with gold are pyrite, chalcopyrite, galena and sphalerite; the gangue minerals are dominated by quartz, sericite, microcline and calcite. The mineralizing event can be divided into four stages: (1) pyrite-quartz; (2) quartz-pyrite; (3) siderite-polymetallic sulfides; and (4) calcite-quartz. Gold occurs mainly as native gold and electrurn in stage I and stage II. There are some evident differences between pyrite from major stages of gold mineralization and that from minor stages; these include differences in crystal forms, size and composition of fluid inclusions.Wallrock alterations consist of sericitization, silicification, pyritization and potash-feldspar alteration. Five alteration zones can be distinguished from unaltered granite (zone 0) to vein lodes (zone IV). Au and Ag increase rapidly from zone 0 to rone IV, Cu increases continuously, while Pb and Zn increase slowly. R-type geological factor analysis indicates that the Au, Ag, Cu, Pb and Zn bear a close relationship to wallrock alteration."

Jan 1, 1994

By D. B. Dreisinger, D. G. Dixon, G. Nazari

"The kinetics of chalcopyrite leaching in acidic ferric/ferrous sulfate media under atmospheric conditions in the presence of pyrite has been investigated. It has been found that pyrite samples from different sources affect the rate of chalcopyrite leaching differently. A strong correlation between the amount of silver associated with the pyrite and its effectiveness has been noted. In this study, improvement of the catalytic properties of pyrite such that all pyrite samples accelerate the rate of copper extraction regardless of their sources is demonstrated, and a detailed discussion of the mechanisms involved in the process of chalcopyrite leaching in the presence of silverenhanced pyrite is presented. INTRODUCTIONIt is well known that chalcopyrite resists leaching in sulfate media. It has been proved that pyrite facilitates the leaching of chalcopyrite (Berry et al., 1978; Dixon et al., 2008; Mehta and Murr, 1983; Muñoz et al., 2008; Nowak et al., 1984, Tshilombo, 2004). Considering the catalytic effects of pyrite on accelerating the kinetics of chalcopyrite leaching, Dixon and Tshilombo (2005) have developed a new process, known as Galvanox™, which has several advantages over other hydrometallurgical processes. Galvanox™ runs under atmospheric conditions, so it requires only low-cost leaching tanks. The sulfur yield at this temperature is high (>95%) which leads to low oxygen consumption and low sulfuric acid generation. The operating temperature is below the melting point of sulfur which eliminates the use of surfactants. This process also does not require fine grinding. Reaction 1 shows the overall leaching reaction in the Galvanox™ process.CuFeS2 + O2 + 2 H2SO4 = CuSO4 + FeSO4 + 2 S0 + 2 H2O (1)Complete copper recovery from the Galvanox™ process can be achieved at a considerably higher rate than other atmospheric ferric sulfate leaching processes (Dixon et al., 2008). Recycling pyrite and recovering copper from tailings with the Galvanox™ process have also been evaluated in continuous pilot leaching campaigns (Dixon et al., 2007)."

Jan 1, 2012

By Gordon L. Kidd

The object of this paper is to show the relations of the East Coulee coal area to the near-by Willow Creek, Wayne, Rosedale, and Drumheller areas, all being parts of the Drumheller field. The word ?area? is here used in a more local sense than that employed by Dr. J. A. Allan, whose. 'area' is rather comparable with the 'mining division' in British Columbia. I have drawn freely from the published information, particularly from Dr. Allan's report on the "Geology of Drumheller Coat Field, Alberta", and from Dr. E. Stansfield's paper on " A Chemical Survey of Alberta Coals", to whom thanks are due. The Drumheller field is served by branch lines of the two principal Canadian railways. The C.N.R. traverses the district by its Goose Lake line from Calgary to Saskatoon; and the C.P.R. by a line from Calgary to Acme and then southeasterly to Drumheller, where it effects a junction with the C.N.R., over which the C.P.R. has running rights as far as Rosedale. From Rosedale, a joint line built during the summer of 1928 extends about forty miles down the Red Deer river to the mouth of Bull Pond creek. From that point the C.P .R. turns more southerly to connect with the Bassano-Empress line. The C.N.R., it is expected, will eventually proceed eastward to connect with a transcontinental line. The joint line from Rosedale down the Red Deer river opened up the Willow Creek and East Coulee areas.

Jan 1, 1929

By Mel Owen, Bob Tipman

"A number of studies have identified the presence of heavy minerals in the Athabasca oil sands. A 1996 Mineral Development Agreement study into the recovery of Co-Products identified low operating costs, a simple flowsheet and access to market as key drivers in advancing interest in a viable project.Commercial bitumen extraction processes recover 50% of the titanium heavy minerals and 85% of the zircon into froth containing 1 % of the feed solids. Froth treatment tailings grade is 11.5% Ti02 and 3.6% Zr02.Processing this high grade feed in a combination of flotation, roasting, screening, gravity concentration and magnetic separation, results in concentrates of rutile, leucoxene, ilmenite, zircon and rare earths of marketable quality.A combination of high grade feed and a simple process lead to operating costs among the lowest in the industry. Low cost heavy minerals and low energy costs indicate an intriguing potential for low cost pigment production in Alberta. The production of heavy minerals from oil sands remains one of the largest untapped resources in the Province of Alberta1.0 IntroductionThis paper describes the results of an investigation into the recovery of heavy minerals from tailings produced by the major oil sands plants. The study was carried out under a Canada-Alberta Mineral Development Agreement (Alberta Chamber of Resources 1996). The MDA Co-Products Study examined the potential for the economic recovery of heavy minerals from oil sands tailings."

Jan 1, 1998

By Jack Parker

"The original design of mine openings and pillars at White Pine was based upon traditional assumptions; i.e., that the principal load is due to the weight of overburden, and that horizontal stresses are equal to one-. third of the vertical.Beginning January, 1964, borehole deformation measurements confirmed suspicions that the principal stress is horizontal and several times greater than the vertical.Vertical stress appears to be directly related to depth, but lateral stresses vary considerably in direction and magnitude. The direction of major principal stress lies parallel to the bedding and is apparently parallel to tension joints. Lateral stresses appear to originate from an igneous intrusive.Mining induces stresses which add to the primitive stresses, in some areas precipitating failure. In this paper, rock failures are illustrated, methods of measurement and typical results are given, and measures to counter or utilize the lateral stresses are described."

Jan 1, 1966