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By M. Aljarrah

The phase equilibria in the Mg-Al-Ca system was investigated experimentally by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques similarly the Mg-Al-Sr system has been studied using DSC and XRD as well as scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) and quantitative electron probe micro-analysis (EPMA). A new ternary solid solution MgxAl4,xSr was confirmed in Mg-Al-Sr system, which is a substitutional solid solution of Mg atoms in Al4Sr. Maximum solubilities of 21.3 at.% Al in Mg17Sr2 and 11.4 at.% Al in Mg were observed. It was also noticed that Mg38Sr9 dissolved 12.5 at.% Al. In the Mg-Al-Ca ternary system, one of the invariant transformations predicted by thermodynamic modeling was verified experimentally and found to occur at 512°C with composition close to 10.8 at.% Ca, 79.5 at.% Mg and 9.7 at.% Al. A ternary solid solution (Mg,Al)2Ca was confirmed where large solid solubility of Al in Mg2Ca was observed.

Jan 1, 2006

By J. Palarski

In the Polish coal mining industry, the use of mine waste in underground backfill has been the most common means of providing ground support to minimize surface subsidence, increasing extraction ratios, and reducing the quantity of waste for surface disposal. Over the last decade attention has been focused on the use of different waste as filling material of underground workings and grouting of roof fall rocks in caving area. In the paper, a brief history of the development of fill technology in Polish coal mining industry is presented. Next, the paper discusses various criteria that should be taken under consideration in the preparation process of a fill slurry and grout, fill distribution systems, mining geometry and placement methods. Moreover, in the paper evaluation of the potential of utilizing coarse and fine waste as a resource material in the production of a backfill slurry and grout for filling and injection in abandoned mines is presented.

May 1, 2007

By w. w. Fraser

"In late 1985, Hudson Bay Mining and Smelting Co., Limited announced the Namew Mine/Mill project. Environmental baseline monitoring and planning began in early 1985 while a major drilling program was under way to delineate the ore deposit. This paper overviews the environmental assessment work conducted for the mine/mill operation, and outlines the tailings and water management practices.Planned environmental works and approach were affected in late 1988 when a massive water problem was encountered in the mine. The requirement to depressurize the rock surrounding the underground workings led to the need to develop, on short notice, an environmentally-acceptable procedure to dispose of a large volume of slightly-saline water.Biological toxicity tests performed on the depressurized effluent proved the effluent to be non-toxic and thus allowed resolution of the disposal problem. This resolution includes the conversion of a large water body from native fish species to a rainbow trout fishery."

Jan 1, 1991

By Robert B. Parsons

"Originally intended to be implemented in 1977, but actually introduced effective May 6, 1974, the earned depletion regulations have been substantially refined and modified since their appearance on the Canadian tax scene, so that this important legislation now consists of a highly complicated set of rules which even the most astute follower of tax law has considerable difficulty sorting out!This month, Tax Notes attempts to cut through this bewildering array oj regulations, in reviewing the main features of the earned depletion allowance applicable to mining operations. Despite the phase-out of earned depletion allowances for most oil and gas operations as part of the federal government's new National Energy Program, earned depletion provisions are still alive and well for the mining sector, although they might well be slowly strangling to death in their own entanglement of complexity!"

Jan 1, 1981

By E. Poiate, P. R. Cabral, A. V. N. Santos, P. V. M. Costa, C. S. Amaral, A. M. Costa

This paper discusses the design of underground salt caverns, opened by solution mining, for the production of brine and storage of natural gas under high pressures. The caverns are located in the salt basin in Maceio City, Alagoas State, at the northeast region of Brazil. Special attention is given to the geomechanical structural design of the caverns using computer codes specially developed for the simulation of excavations in salt rock formations, considering validated constitutive creep laws under different initial stress states and temperatures. The behavior of sedimentary rocks intercalations presented in the salt layer is simulated using elastic-plastic models. The excavation of the caverns by solution mining is also simulated starting from a geostatic initial equilibrium state of stresses, with a unique formulation only implemented in these computer codes, without the need of the application of boundary stresses to the model in order to develop the initial state of stresses. These computer codes have being used in the design of several clusters of caverns for brine production used as raw material of Poly Vinyl Chloride (PVC) of the Chemical Industryin Brazil. These computer codes and methodology were also applied to the design of the underground conventional potash mine in the state of Sergipe, overlying tachyhydrite and carnallite with very high creep strain rate. They have also been used in the design of the pre-salt oil wells through thick layers of stratified salt rock in Santos Basin, for the exploration and production of the pre-salt reservoirs in Brazil. The constitutive creep equations implemented in the codes are based on a double mechanism creep law. The creep constants adopted in the simulation are taken from a previous investigation carried out on an experimental panel of the potash mine, considering the stratified geology with different salt rocks of the basin where the mine is located. These constants were also obtained by lab tests under different confined and differential stresses and temperatures.

Jan 1, 2015

By E P. Graham

Orebodies occur in an infinite variety of grades, shapes and sizes, and take many millions of years to grow. When extraction starts there is only one possible end -the mine sooner or later will run out of ore and shut down. If the mineral industry is to supply the ever increasing demands of modern civilizations, more and more metals must be found and mined. This will require a never-ending search for ore, and the development of every economic body, large or small. To justify the mining of a small orebody, it first of all must pay its way. If the size of the burden imposed by the capital cost estimates is not carefully worked out, an otherwise promising situation could be killed. The very nature of mining, as a transient industry, re-leases a steady stream of good used equipment, and the trained personnel to install and operate it. All manner of plans and layouts, which can be utilized at a new property, are available. Working these and other economies into the estimates will sometimes make enough difference to give a prospect the green light.

Jan 1, 1964

By W. A. Lang

Introduction That the coal industry has entered a new phase in its development is now evident. Coal, besides being the chief source of heat and power, has become a potential raw material for many industries. Rapid progress has been made in the methods used in the mining and preparation of coal, and in the equipment for the burning of coal. Data of a fundamental nature relating to the composition of coal and to its transformations? during combustion and processing have also been revealed. Research, the key which has opened this new era, has already accomplished much, but it has only begun to show what it may and should be able to do. New developments of coal burning equipment, super-power plants, carbonizing and briquetting plants, hydrogenation and synthetic chemical processes, will undoubtedly have a marked influence in the post-war years on the economic welfare of many coal producing countries. Until comparatively recently, however, there has been in many branches of the coal industry a tendency to regard research as something abstruse and something which had little or no value to those managing such branches. But the fact that coal has suffered as a source of heat and energy through inroads of oil, natural gas, and water power, has made it plain to the industry that, if it is to maintain its present markets in this competitive world, much less increase them, the whole industry must be willing to follow the example of other industries and plan for the future.

Jan 1, 1946

By L. Tong

"The oxidation of Quebracho was evaluated by acid-butanol assay, which indicates depolymerization of Quebracho. Anthocyanidin, an oxidation product of Quebracho, is stable at 95?C for up to 2 h. The ionization, complexation, and oxidation properties of Quebracho were discussed. Complexation of metal-Quebracho occurs at ambient temperature. The formation of complex precipitates is influenced by the acidity of the solution. Temperature is another important parameter that influences the oxidation and the complexation of Quebracho. Quebracho-ferric complex precipitate forms at 90?C, 0.1 mol/L H2SO4. The formation of Quebracho-metal complex in the leach solution is a possible reason for the consumption of Quebracho. Quebracho molecules adsorption on the mineral surface is reduced by consumption of Quebracho, resulting in poor sulfur dispersing effect in the leaching process. INTRODUCTIONQuebracho is used as a sulfur dispersing agent (SDA) in the pressure leaching of zinc concentrate as stated in U.S. Patent No. 3,867,268 (1975). It prevents the zinc sulfide particles from being coated with molten sulfur, thus preventing the inhibition of the zinc leaching reaction. Recently, the sulfur dispersing effect of Quebracho was investigated in the oxygen pressure leaching of nickel concentrate. The oxygen pressure leaching of pentlandite can be represented by reactions 1-3."

Jan 1, 2012

By C. J. Hartley

"Scandium oxide can be recovered as a by-product from process streams in a number of chemical and metallurgical plants including TiO2 sulphate pigment, Ni/Co laterite, zirconium oxychloride and uranium operations. The feed materials available for processing can be either mid or end of process streams containing many species in solution. This paper describes the strategies available to limit coextraction of elements into scandium containing streams from TiO2 pigment production and the removal of these elements to deliver high purity scandium oxide.A critical part of process development is to work within the constraints of the main process in terms of introducing new unit processes and producing minimal additional process intermediates and residues. This requires flexibility in designing flowsheets and plants to find novel process routes that avoid production of intermediates and/or the introduction of reagents that can compromise the main process operations.Bloom Energy has developed novel solvent extraction processes for the extraction and refining of scandium oxide that minimise impacts on core process streams within TiO2 pigment plants. The additional unit processes are designed to have minimal contact with pigment plant process streams to produce a concentrate that is refined to nominal 3N purity scandium oxide in a simple, small scale commercial plant."

Jan 1, 2016

By J. Costigan, C. Corless

In 1997, damage as a result of Castrol R40 entering the INCO pressure carbonyl plant carrier gas stream was becoming increasingly severe. The oil in the gas stream was adversely affecting both equipment availability and process control resulting in rising unit costs. The main source of the Castrol R40 was determined to be the carrier gas and low pressure gas blowers. Plant personnel initiated a plan to prevent the Castrol R40 from entering the carrier gas stream by replacing the mechanical shaft seals with Ferrofluidics seals on these blowers. The following paper details a brief case history of the Castrol R40 in the carrier gas including impact on the plant. This will be followed by a technical discussion of the new sealing arrangement that was developed by plant personnel, Roots Blower and Ferrofluidics. Lastly, this paper will update the status of the blower upgrade project and document the results to date.

Jan 1, 2000

By W. J. Cherones

This paper describes the history of the development and application of the electric mining shovel in open-pit mining, dea1ing particularly with far-reaching advancements in three primary areas: metallurgy, mechanical design and electrical systems. Hoist drives and crowd drives, including the Magnetorque and Electrotorque systems, and the integral propel drive are given close attention.

Jan 1, 1972

By J. E. Gill

THE 1938 season was marked by a distinct lull in exploratory activity in the Province of Quebec. Quebec was not unique in this respect, but the condition appears to have been more acute here than in most other parts of the Dominion. Various causes may be suggested to account for this. The general disturbance in political and economic conditions throughout the world has certainly had an adverse influence. Uncertainty induced by changes in the mining laws of Quebec in 1937 contributed. A third cause was the belief, now held by many, that the easily accessible deposits in the main producing belt extending eastward from. the Rouyn district have now all been found and that new discoveries in this field will henceforth come more slowly and more expensively. A fourth is the lack of conspicuous success by companies and individuals who have interested themselves in less accessible areas to the north, notably the Chibougamau district. A fifth, the unattractive appearance, as viewed on published geological maps, of the vast area extending northward to Ungava bay and Hudson strait. A sixth, the attraction of such speculative funds as were available to the Northwest Territories, where spectacular finds were reported in the fall of 1937. Whatever may be the relative importance of these causes, languor in exploration will ultimately be reflected in production returns. This appears, therefore, to be an opportune time to take stock of the general position of the Industry in the Province and to consider ways and means of counter-acting those conditions which are now impeding, or will in the near future impede, its expansion. At the request of the Institute Secretary, Mr. Carlyle, I have prepared a brief summary of accomplishments to date and a discussion of some of the geological aspects of the problem.

Jan 1, 1939

By I. Yarita

Magnesium alloys have the lowest density among the metals in practical use, and have properties such high specific strength, electromagnetic interference shielding and good vibration damping. Thus, there are many applications of these materials in automotive and electric parts. However, there is a little use of the products of metal forming of these materials because of poor plastic deformability in the normal temperature range and their high cost of production. To expand the range of application of products manufactured by metal forming, rolling technology for producing thin sheets having good mechanical and surface qualities is required. In this study, hot-rolled Mg-alloy sheets are experimentally rolled with or without lubrication in the temperature range from 293 K to 523 K. Rolling force, plastic deformability and surface quality are investigated, and the grain structures and their uniformity are observed. The effect of friction between the roll and the deforming material on the uniformity of the grain structure is discussed. Moreover, rolled materials are annealed and their mechanical properties are investigated by the tensile test and compared with those of as-rolled materials. The effects of the rolling conditions on the mechanical properties are discussed.

Jan 1, 2006

By D. R. Lentz, S. H. Mcclenaghan, J. A. Walker

"Abstract - The Orvan Brook deposit is one of several (Zn+Pb>>Cu)-rich sulfide deposits hosted by the Spruce Lake Formation (California Lake Group) in the northwestern part of the Bathurst Mining Camp. This parautochthonous deposit is hosted by a narrow band of highly deformed, locally graphitic shale that appears to conformably overlie felsic volcanic rocks of the Spruce Lake Formation, and is in tectonic contact with overlying mafic volcanic and related sedimentary rocks of the Canoe Landing Lake Formation. The Spruce Lake Formation is dominated by felsic volcanic rocks and subordinate fine-grained sedimentary rocks, and mafic volcanic rocks (Canoe Landing Lake member). The felsic volcanic rocks can be divided into aphyric and feldspar-phyric rock types. The feldspar-phyric rocks and a few of the aphyric varieties have a Zr/TiO2 ratio of 0.06, and fall into the California Lake Group field on a Y/TiO2 versus Zr/TiO2 diagram. In contrast, the aphyric felsic volcanic rocks have Zr/TiO2 ˜ 0.09 and are marked by high Zr and Th, which is consistent with highly fractionated felsic magma of Spruce Lake affinity. Major and trace element analyses of host rocks suggest that weak to moderate hydrothermal alteration developed on the south side (stratigraphic footwall) of the deposit, which is consistent with a north-younging succession. The sulfide lens strikes east-west for approximately 2.3 km, extends down-dip for at least 500 m locally, and has an average thickness of between 0.75 and 1 m, but is locally up to 5.5 m thick. The contacts of the massive sulfide lens with its host rocks are invariably sharp. Host rocks show evidence of intense ductile deformation as well as later brittle deformation. Compositional layering and sulfide breccia textures in the sulfide body are interpreted to result from deformation or tectonic enhancement of original primary layering. The deposit contains an estimated resource of 2.69 Mt grading 1.73% Pb, 5.95% Zn, 0.37% Cu, 72 g/t Ag, and 0.9 g/t Au. Similarities in bulk d34S between the Orvan Brook (+8.6‰) and the nearby Cu-rich McMaster deposit (+8.2‰) suggest a common depositional setting."

Jan 1, 2006

By Eurípides do Amaral Vargas Jr., J. A. de Mello Franco

"It is frequently necessary to excavate a tunnel for Civil Engineering purposes, or wells for petroleum exploitation, in laminated rock mass like schists or phyllites or in highly foliated gneisses. The determination of the pre-existing in situ stresses is essential, in order to assure the stability of these excavations. In most cases, the pre-existing triaxial stress field is arbitrary in relation to the tunnel or well axis. For these rock masses the concept of Generalised Plane Strain can be correctly utilized.There are closed form solutions for the calculation of stresses in anisotropic rock masses under Generalised Plane Strain conditions (Lehknitskii, 1981 and Hong , 1994). Based on these analytical solutions, established for the cases of Generalised Plane Strain, a synthetic problem will be formulated: the theoretical in situ stress tensor acting on this rock mass will be determined, with the aid of Bayesian Inverse Problem Techniques, as developed by de Mello Franco (2009). Additionally, the reliability of results obtained will be evaluated, in accordance with the research performed by this author. INTRODUCTIONThe Inverse Problem Technique, as developed in the paper, is based on the definitions and concepts obtained from the current literature and used for the solution of Inverse Problems, but the innovation to be presented is the utilisation of Bayesian Techniques and the determination of the reliability of the results obtained. This will be shown in a synthetic example where the determination of the in situ stress tensor, from strain measurements in a drill hole is supposedly performed. It is assumed that this drill has its axis arbitrarily placed in relation to the rock mass. Generalised Plane Strain conditions will hold for use with problem. The equations of Beltrami – Mitchel, in agreement to Lekhnitskii (1981) and Ong (1994), will be used in this synthetic case, for calculating strains, hypothetically measured in the hole before the final excavations. Finally a synthetic example for the determination of the in situ stress in a fully anisotropic rock mass, based on Bayesian Techniques and its reliability, developed in de Mello Franco (2009) is presented."

Jan 1, 2015

By J. Jung, W. Keller, N. Rohn

In hydrometallurgical minerals processing slurries are often processed at very small grind sizes and high solids concentrations. This normally results in flow anomalies of such slurries. Due to flow limits or yield stress the slurry tends to stagnate close to the vessel bottom, the walls and at any internals. The main mixing task therefore generally is not suspending of the solids but the homogeneous blending of the entire vessel volume. If not considered during the agitator design only a fraction of the vessel contents will be mixed. Therefore the knowledge of the slurry rheology as well as the variations in process parameters is vital to design e.g. storage or surge tanks. The integral mixing solution considers the motor power, the choice of the impeller type and number, the impeller diameter as well as the design of the baffles and feed and discharge positions.

Jan 1, 2014

By C. J. Newman, K. Molnar, A. G. Storey, G. Macfarlane

"The Kidd Creek copper smelter started operation in June 1981 using the Mitsubishi Continuous Smelting Process. A steady increase in plant production rates has been demonstrated, and the annual tonnage of concentrate smelted is now double the original design rate. This paper summarizes recent modifications made to increase concentrate feed rates, increase on-line time, reduce copper losses and control the impurity level in anode copper. It includes improvements made to furnace design, improvements to reduce downtime f or boiler cleaning, and improvements made to the acid plant to allow handling of increased gas flowrates and higher gas strengths while maintaining low acid plant emission rates. IntroductionThe Kidd Creek Division of Fal conbridge Limited operates a base-metal mining and metallurgical complex, located in Timmins, Ontario, which includes an underground mine, a 13 500 tonne/day concentrator, a 130000 tonne/year zinc plant and a copper smelter and refinery, The copper smelter and refinery were commissioned in 1981, with an installed capacity of 59 000 tonnes/ year of cathode. The smelter, utilizing the continuous smelting technology of the Mitsubishi Process, has subsequently been expanded in production capacity, and in 1991 produced 113 500 tonnes of blister copper The capacity of the refinery, which uses Onahama No. 3 tankhouse technology, has been increased to 96 000 tonnes/year of cathode. The capacity increase at the smelter has been realized through the input of additional oxygen to both the smelting and converting furnaces, without increasing the process off-gas flowrate through the associated waste heat boilers.In this paper, a brief review of smelter operation and modifications in the period 1982 to 1987 is presented, together with a more detailed discussion of operation during 1988 to 1991, and a discussion of future planned improvements."

Jan 1, 1992

By Serena Biella

Gold has received a growing interest as a catalyst for the selective oxidation of organic molecules using oxygen under mild conditions1. In the liquid phase application small gold particles (2.5-7 nm) deposited over different solid supports can be used but, like many other noble metals, their catalytic activity depends upon the nature of the support and the preparation metod2-5. In particular, gold on carbon is the preferred catalyst for the oxidation of the alcoholic 2-7 and the aldehydic7-9 groups and one of the best preparation method is the immobilisation of colloidal particles2-5,8,9. Suggested application of gold catalysis in fine chemicals production, tested on laboratory scale preparations, is reported in table 110. In order to produce more efficient catalysts for the liquid phase oxidation and to derive new insights into the reaction mechanism, we have made a comparison among catalytic systems based on different metals. The first effort was to test the activity, if present, of naked metal particles and then to study the influence of various materials commonly used as a support.

Oct 1, 2003

By Jiuhua Xu, Yuling Xie, Fenglei Bie, Neng Jiang

"Abstract - The Xiaoqingling Mt. area is one of the most productive gold districts in China. The gold-bearing quartz veins are controlled by a series of east-west shear zones within the Archean Taihua Group, and related to the late Yanshanian (Cretaceous) granite. The major metallic minerals are native gold, electrum, pyrite, galena, chalcopyrite and sphalerite, with gangue minerals dominated by quartz, sericite, ankerite, and calcite. The host rocks are mainly amphibolite, plagioclase gneiss, and migmatites. Principal alteration is sericitization, silicification, pyritization, and carbonization.There are four generations of hydrothermal quartz in altered rocks of gold deposits. The earliest generation of quartz, (Q1), occurs in altered amphibolite gneiss and migmatite, and typically contains fluid inclusions with halite crystals (type A) and two phases, (L+V), of fluid inclusions (type B). The salinities of type A inclusions are 32 wt% to 52 wt%, with dissolution temperatures of halite crystals being from 155°C to 465°C. The second generation of quartz, (Q2), occurs as a fine-grained aggregate associated with sericite, and has small (less than 3 µm) type B inclusions. The third generation of quartz, (Q3), occurs in mylonitic, intensively altered rocks and specially beresite (a type of rock composed of quartz, sericite, and pyrite) near the veins, and contains large amounts of CO2-rich fluid inclusions (type C-fluid inclusions with liquid CO2 and type D-fluid inclusion with high density CO2). The CO2 contents of type C range from 72.6 to 87.4 mol% in gas phases, and 35.7 to 68.3 mol% in liquid phases, based on Laser Raman analysis. The homogenization temperatures of fluid inclusion type A and C are from 215°C to 380°C, and from 210°C to 325°C, respectively. The minimum trapping pressure of fluid inclusions is estimated as 80 MPa to 170 MPa for type A, and from 57 MPa to 190 MPa for type C, which approximate to those of fluid inclusions in vein quartz.The ?18O of quartz are from 10.4‰ to 11.0‰ for Q3 of altered rocks, and from 10.7‰ to 12.8‰ for stage I quartz. The calculated ?18O of fluid inclusions varies from -1.3‰ to 6.0‰. The ?D of fluid inclusions ranges from -67‰ to -59‰ and from -81‰ to -48 ‰, respectively. It is concluded that the water in the hydrothermal fluids both reacting with wallrocks and precipitating orebodies could have been mainly of magmatic and/or metamorphic nature. However, local meteoric water might have been important in late mineralization, because of a distinct oxygen-shift toward the meteoric water. The ?34S values for pyrite of the ores range from -7.1‰ to +7.1‰, with an average of +2.9‰. Those of other sulfides (chalcopyrite, galena, and sphalerite, range from -12.5‰ to 8.3‰. The ratios of lead isotopes for galena of the ores are: 17.06 to 17.31 (206Pb/204Pb), 15.43 to 15.74 (207Pb/204Pb) and 37.58 to 38.45 (208Pb/204Pb). In summary, ore-forming fluids in the Wenyu-Dongchuang gold deposits may have originated from a mantle and/or lower crust source, and ore materials were derived from the Precambrian basement, the Taihua Group."

Jan 1, 1998

By R. M. Giegerich

"This paper begins with a brief history of Madawaska Mines, a brief description of the geology, mining methods and equipment, and the historical development of 7/8-in. tapered drilling equipment. It then outlines the performance characteristics and inherent problems of the traditional 12-degree, tapered connection, blade-type insert bits. Service-free (Unipass) button-type insert bits are presented as a possible solution to these problems. The paper concludes with an analysis of button bit performance to date.Brief History of Madawaska MinesMadawaska Mines Limited, near Bancroft, Ontario, is in Faraday Township, Hastings County, approximately 100 miles northeast of Toronto and 100 miles west of Ottawa.The mine re-opened in 1976committed to 1,500 tons per day to provide approximately 600,000 pounds of yellowcake (U3O8) per year to A.G.I.P. (an Italian government agency) under the joint ownership of Federal Resources Corporation, Salt Lake City (51%), and Consolidated Canadian Faraday Limited (49%). At present, the mine is producing approximately 2 pounds per ton (.1% U3O8) at the rate of 60,000 pounds per month. The mine employs about 400 employees.Brief Description of Geology, Mining Methods and EquipmentGeologyThe Grenville metasediments of the mine area are chiefly paragneiss, amphobolite and some carbonate (marble) rocks, which were intruded by a basic rock, altered to a metagabbrometadiorite. These formations are generally concordant, striking east to northeast and dipping 45 to 60 degrees to the south. Locally, the metagabbro is often discordant. The above group of rocks (mixed hybrid gneisses) forms the hanging wall of the south-dipping Faraday granite sheet and was intruded by nepheline syenite, syenite and granite. The ore occurs in the granite-syenite-pegmatite dykes that are probably genetically related to the Faraday granite. The ore shoots are erratically distributed within the pegmatite bodies, mainly on the hanging or footwalls but also medially. Their size varies from 50 to 350 feet in length, 5 to 40 feet in width and 50 to 200 feet in height. The ore occurs most frequently in a medium-grained granite or syenite, well hematized with 10 to 30% mafic crystals of pyroxene, amphibole and/or relics of the host rock."

Jan 1, 1982