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By Donald S. Macdonald

"I AM thankful for this opportunity to address the Toronto Branch of The Canadian Institute of Mining and Metallurgy. The Members of your Institute can have a great influence on the direction in which the mineral policies of Canada will evolve, and to assure that optimum benefits from our country's vast mineral resources will accrue to the nation as a whole and to all its citizens. Today, I want to: (1) offer an outlook on the mineral industry for 1973; (2) talk briefly about the role of minerals in the total economy; and (3) outline some of our thinking with respect to a national minerals policy for Canada."

Jan 1, 1973

By P. G. Hallof

The exploration staff of Campbell-Chibougamau Mines Limited has used past experience to delineate several areas of geologic interest under Lake. Chibougamau. Du• ring the winter of 1964-65, a reconnaissance induced polarization survey was carried out on the lake. First, several lines were surveyed over the known mu1.erahza-tion at the Henderson mine; the grid was then extended into the areas of interest. Several anomalous zones were located and drilled; one, of these proved to be of economic interest.

Jan 1, 1967

By Ham. Y. M.

The corrosion behaviour of Al-B4C metal matrix composites immersed in 2500 ppm boron-containing H3B03, 0.5 M K2SO4, and 3.5% NaC1 solutions was investigated. Effects of B4C particle volume fraction on the corrosion behaviour of composites were studied using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. Scanning electron microscopy was employed to study the surface morphology of the material before and after corrosion. Results show that all materials investigated are more corrosion resistant in 2500 ppm boron-containing H3B03 than in other solutions. No appreciable corrosion was observed in boric acid and sulfate solutions in contrast to an obvious pitting in NaC1 solution for both base alloy and composites. The preferential pitting sites are the interfaces of Al/Fe intermetallics for the base alloy, and the A1/B4C interfaces for the composites. Increasing the volume fraction of B4C particles in the composite decreases its corrosion resistance of Al-B4C composites.

Jan 1, 2011

By S. Borle

The microstructural features produced in friction stir welded AZ31, AZ80 and AZ91 alloys are examined when different welding parameters are applied. The microstructures primarily consist of a-Mg grains with a-Mg + Mg17A112 colonies, however melted films of Mg17A112 are produced in AZ91 alloy when high rotation speeds are applied. When the rotation speeds are slow, or the travel speeds are fast the Mg17A112 were incorporated into the stir zone, however they do not exhibit an elongated lamellar morphology associated with melted films. In the case of AZ80, the extruded base material contains a smaller fraction of Mg17A112 and few of these phases are observed in the stir zones. The results are explained based on the dissolution rate and melting temperatures of Mg17A112 controlling the overall morophology and fraction of phases in the stir zone.

Jan 1, 2011

By Larry G. Twidwell, Corby G. Anderson, Camille M. Fleuriault

"The selective precipitation of iron as ammonium jarosite is a well-established industrial technology in base metals hydrometallurgy. It is a key technology in minimizing iron tenors which would be disruptive to downstream processing. It also provides a more readily filterable iron solid to better facilitate materials handling. This paper elucidates the fundamentals behind industrial iron precipitation. Then, the details of the successful optimization of an industrial ammonium jarosite circuit are presented.HYDROMETALLURGICAL IRON REMOVAL FUNDAMENTALS Iron is the fourth most abundant element in the Earth’s crust (5% by weight) and is often found in complex ores such as sulphide-bearing formations. Iron represents an issue though during leaching, a technology which is widely used for the treatment of this type of ore: •,Iron has the particularity of forming hydroxides when leached under certain conditions. Iron hydroxides form a viscous gel, which is difficult to filter and traps valuable elements such as silver. •,Iron is solubilized along with other metals and interferes with the subsequent extraction steps. As a result, purification of the pregnant leach solutions is required to achieve economical extraction of base metals. In the 1960s, metallurgists developed iron precipitation processes for solution purification (Habashi, 1999). Nowadays, precipitation of iron bearing species, such as goethite, hematite or jarosite, has become one of the most common methods used in the industry to purify leach liquors. To be suitable, the precipitate has to be readily filterable and thus must not be too fine of particle size. Precipitation can take place in autoclaves at medium to high temperatures, under an oxygen or air overpressure (Tourre, 1984, Fleuriault 2016, Fleuriault Anderson Shuey, 2016))."

Jan 1, 2016

By S-E. Vandat

The goal of this work was to select an appropriate electrode for dummy load of diesel engine in fully salt-water in the DESA factory. The electrochemical corrosion rate of general structural steel, commercial pure aluminum and cathode copper calculated as weighting, volumetric and commercial in fully salt-water by city power. After several tests and then applying the fuzzy logic method, it was determined that general structural steel is the best selection for this purpose.

Jan 1, 2005

By D. H. Wilton, C. I. Godwin, A. J. Sinclair

"A computer-based drill core logging system used to examine computer-based drill core logging system used to examine copper mineralization hosted in volcaniclastic rocks at the Sustut deposit, in north-central British Columbia, has many advantages over conventional logging. A relatively simple format for recording geological information allows complex, but significant, geologic parameters to be recorded consistently, accurately and quickly. This allows graphical presentations and statistical interpretation of the data that lead to rapid and detailed analyses of the control and distribution of copper mineralization at the Sustut deposit.Ore mineralization is concentrated in lens-shaped bodies and is zoned from native copper cores through chalcocite, bornite and chalcopyrite to a margin containing pyrite. Chalcocite, the principal mineral, occurs mainly in volcaniclastic agglomerate characterized by a specific grain size, a narrow range of matrix and fragment proportions, and a specific sorting.IntroductionWe report here a case history of the practical application of a detailed computer-based drill core logging system applied to the Sustut copper deposit of Falconbridge Nickel Mines Ltd. The Sustut deposit, containing a few tens of millions of tons of ore grading slightly more than one per cent copper (Church, 1975), is in north-central British Columbia about 875 km north of Vancouver. The deposit is contained in volcaniclastic sedimentary rocks of the Upper Triassic Moosevale Formation, which is within the upper part of the Takla Group (Monger and Church, 1977) of basic volcanic and associated sedimentary rocks. Takla rocks occur along the eastern fringe of the Intermontane Belt in the Canadian Cordillera (Sutherland Brown et al., 1971). The deposit consists of concentrations of copper sulphides, native copper and pyrite within pods and lenses parallel to bedding in the host sedimentary rocks. These sheet-like deposits exhibit a mineral zoning from pyrite at the fringes successively through chalcopyrite, bornite and chalcocite to native copper at the core (Wilton, 1978; Wilton and Sinclair, 1979)."

Jan 1, 1980

By G. A. Vissac

IN THE preliminary design of a coal washery, the most important factor to evaluate is the ash content of the final product. The ash content permissible may be imposed by market demands, but, in the final analysis, sooner or later - as most consumers today are buying coal on a 'heat value' basis - the coal operator has a certain margin of latitude. and the ash content of the coal to be delivered can be determined on the basis of maximum returns and highest profits. A few years ago, the most desirable separation was selected on the basis of the plus-minus 0.10; that is, the most desirable gravity of the separation was selected at the point showing a minimum amount of near gravities in the raw coal. The reason for this was an expected wide error over these near gravities. Today with the recent development of cry accurate, automatically controlled cleaning apparatus, a much larger latitude is possible, and the most desirable gravity of separation can be selected, almost exclusively, on the basis of the economic factors involved. To illustrate these new methods of investigation we shall give two examples, based on actual coals from the western United States.

Jan 1, 1957

By M. W. Wadsley

"Physical and chemical property models are widely used in process engineering. There exist, in the published literature, completely empirical models of ''thermodynamic properties"", that is, property models that are not consistent with the laws of thermodynamics. There also exist property models that purport to be thermodynamically consistent but are flawed in their implementation. There are also published property models that are consistent with the laws of thermodynamics but that do not reproduce property values with an acceptable accuracy. A practicing engineer might be asked to assess very different property models for which there are a variety of claims. This paper discusses features of thermodynamic and empirical property models that may assist in their practical evaluation and implementation."

Jan 1, 2005

By Jose R. Hernandez-Aguilar

"This paper revisits data from previous studies (Hernandez-Aguilar, 2010, 2011) to better understand the link between metallurgical performance and bubble size (Db) in the collection (pulp) zone of full-scale flotation systems. To obtain conclusive evidence exclusively related to the collection zone, the experiments were designed in those studies to control both the bubble generation method and the influence of the froth zone on the overall metallurgical performance in industrial and pilot-scale flotation columns. The results showed that generating small (1 mm) bubbles had a significantly higher beneficial effect on the recovery of coarse (> 75 µm) particles compared to the effect on fine (< 16 µm) particles. It was observed that, under certain practical conditions, the recovery of liberated coarse particles was close to zero, but could be recovered almost completely by reducing bubble size. The evidence revealed an apparent inconsistency of the so-called “k–PSb” model: at constant froth recovery, increasing Sb did not always result in higher recovery, as the model predicts. Overall, the evidence showed that it was not the Sb but the bubble size that proved to be a more reliable link to metallurgical performance. Only under highly suboptimal bubble size conditions (Db = 3 mm) did the froth zone seem to play a role, possibly reflecting an effect of pulp-zone bubble size on froth stability. However, for the most part, both the bubble generation method and the froth zone played inconsequential roles. An empirical model that better describes the kinetics of particle collection is proposed.INTRODUCTIONStudies showing the link between metallurgical performance and the interactions of bubbles and particles in the collection (pulp) zone of industrial flotation systems are scarce. A common belief among a number of mineral processing practitioners considers that “small” bubbles are favourable to recover “small” particles and that, conversely, “larger” bubbles are more efficient at floating “coarse” particles. However, perceptions like this are often substantiated by anecdotal evidence rather than by rigorous data analysis. What is the optimum bubble size for a particular case, how operating conditions can be adjusted to control a target bubble size, and whether the bubble size needs to be changed in the first place to optimize the operation of a flotation plant are questions that usually remain without solid answers.The studies reported by Hernandez-Aguilar (2010, 2011) were, in part, performed to test the effect of bubble size on flotation response and, thus, help address some of the above questions. The focus of the studies was to optimize the metallurgical grade-recovery performance of the Cu-Mo separation plant at Teck’s Highland Valley Copper mine (HVC). The outcome was compelling and significantly valuable: consolidated production data showed that in 2008 – the year when the recommendations from the studies started to be implemented – the Mo plant recovery was 89%, and gradually increased to 92% and 94% in 2009 and 2010, respectively, along with an increase in Mo concentrate grade. (Note: these production figures were not included in the publications quoted above; however, they were shown during an oral presentation at the 43rd Annual Meeting of the Canadian Mineral Processors in 2011.)"

Jan 1, 2016

By Holly L. O. Huyck

Disseminated hypogene sulphide mineralization in the Lakeshore porphyry copper deposit (also called the Cyprus-Casa Grande deposit) of Arizona occurs in both a granodiorite stock and associated volcanic rocks. Structural development and vein paragenesis at Lakeshore are similar to other Laramide porphyry copper deposits of the southwestern U.S. Two major structural trends are present: intrusive contacts, copper-bearing potassic alteration veins and major post-mineralization Basin-and-Range type faults trend N-NW, whereas phyllic veins and secondary post-mineralization faults trend N-NE, and deep propylitic veins trend NE-ENE. Lithologic permeabilities, caused by fracturing in all rocks and by grain size distributions in volcanic rocks, controlled the distribution of copper mineralization. Differences in chemical compositions of host rocks did not affect are grade. Structural control, through density of chalcopyrite-rich veins, was the major control of are grade. Fracture density of other potassic vein types did not strongly affect grade. Within volcanic lithologies, permeability, as indicated by grain size distribution, provided a second-order, but significant, control of mineralization.

Jan 1, 1990

By Parsons. Robert B.

"Starting this year, corporations that conduct business in Ontario face a new tax a corporate minimum tax. This tax is in addition to the myriad of other taxes that make up a corporation&apos;s total tax burden including federal and provincial capital 1oXJ!S, payroll tax and sales taxes. Mining companies with gross revenues in excess of $10 million or total assets exceeding $5 million may be liable for this new tax. IntroductionOn December 8, 1993, the Ontario government introduced legislation to implement the corporate minimum tax (CMT promised in its May, 1993 budget. There are very few differences between the final legislation and the budget proposals.The CMT is effective for taxation years commencing after 1993. Subject to certain specific exemptions (detailed below), the tax applies to all corporations liable for Ontario Corporate Income Tax that have either gross revenues in excess of $10 million or total assets in excess of $5 million. These measurements apply to the aggregate gross revenues and total assets for all corporations in an associated group and a corporate partner&apos;s share of partnership assets and revenues must be included in the determination.In essence, the CMT is an income tax that is based on financial statement profit instead of an income amount that is determined separately under a statute. Accordingly mining companies (including so called ""junior"" exploration companies), which traditionally sheltered their taxable income by claiming generous exploration and development deductions, could find that they have a CMT liability."

Jan 1, 1994

By M. Saghaeian, R. Hejazi, Sheikhzadeh. V., A. Abazarpoor

"The morphology of iron ore concentrate particles is known to influence several properties of iron ore pellets, including drop number, compression strength, and reduction properties. This study aimed to determine why grinding methods and particle morphology influence green pellet properties. Particle morphology can be directly related to the grinding method: ball mill (BM) or high pressure grinding roll (HPGR). In this research, two iron ore concentrates, namely Gol-e-gohar and Ardakan, were ground by a BM and HPGR to produce a suitable Blaine value for pelletizing (nearly 1,900 cm2/g). Morphological features of particles were subsequently investigated by sieving and cyclone sizing for particle size distribution, the Brunauer-Emmett-Teller (BET) and Blaine methods for specific surface area (SSA) and scanning electron microscopy (SEM) for the evaluation of shape descriptors. It was concluded that HPGR resulted in generating a greater proportion of fine particles compared to ball milling. The BET results showed that the SSA of HPGR pellet feed was higher than that from the BM due to a greater proportion of cracks, indents and bulges and the creation of new fracture surfaces. SEM images processed by ImageJ software indicated that particles ground by the BM tended to be more rounded and less elongated than HPGR particles because of the breakage model of each method. To show the effect of morphology on the green pellet quality, green pelletizing was performed in a pilot pelletizing disc. The HPGR pellet feed had a higher drop number in comparison to the BM pellet feed, due to the angular and rough shape of the particles.INTRODUCTIONThe demand for fine or ultra-fine particles as feed material for ceramics, composite materials, and mineral processing is on the rise (Kotake, Kuboki, Kiya, & Kanda, 2011). The final concentrate of iron ore processing plants (filter cake) has a size range roughly between 0 and 300 µm, depending on the liberation of Fe containing particles (Meyer, 1980). In general, to produce a suitable pellet feed of appropriate quality, Blaine numbers of 1800–2000 cm2/g should be achieved (Van der meer, 2015)."

Jan 1, 2016

By A. A. Ruitenberg, L. R. Fyffe

"This paper compares several distinct types of mineral deposits associated with different families of granitoid rocks in the New Brunswick Appalachians. Porphyry copper deposit s are associated with late-stage differentiates of Lower to Middle Devonian I-type igneous complexes. Contact metasomatic deposits were formed where these plutons intrude carbonate rocks and they gave rise to vein deposits in fracture zones near wrench faults. The I-type granitoids were emplaced mainly in areas of thin continental crust and locally along prominent faults in areas of thick continental crust.In contrast, tin-tungsten-molybdenum-bearing greisen deposits and skarns, and antimony-bearing quartz veins are associated with predominantly S-stype granitoid complexes ranging in age from Middle Devonian to early Carboniferous. The mineral deposits occur within or along the contacts of very fractionated (specialized) late phases of these intrusive complexes, which are characterized by high K2O/Na2O, Rb/Sr and Rb/Ba, and low Fe, Mg, Zr and Ti contents. These specialized granitoids are in a large wrench fault zone that cuts across thick continental crust in southwestern and central New Brunswick.IntroductionA great variety of igneous intrusions and subvolcanic stocks were emplaced in the New Brunswick Appalachians during the latter stages of and immediately after the Acadian Orogeny (late Lower to Middle Devonian) and during the subsequent Hercynian Orogeny (Carboniferous). The presence or absence and characteristics of mineral deposits associated with these intrusions reflect the level of intrusion, the composition of the associated igneous rocks and the composition of the invaded sequences.Nickel-copper sulphide deposits occur in mafic intrusions in the St. Stephen area of the southwestern Magaguadavic - St. Croix Zone and in the Goodwin Lake area of the northeastern Mirarnichi Zone. Contact metasomatic and vein-type copper-rich base metal sulphide deposits and porphyry copper deposits with or without molybdenum are related mainly to high-level granitoid stocks of intermediate composition in the Matapedia-Tobique and northwest Miramichi zones. Tintungsten - molybdenum deposits with or without base metal sulphide minerals and antimony-uranium deposits are mainly associated with Upper Devonian and Lower Carboniferous biotite-muscovite granites and related &apos;subvolcanic intrusions that occur in an arc-shaped belt extending from the southwestern Magagaudavic - St. Croix Zone into the central Mirarnichi Zone."

Jan 1, 1982

By R. Harrisson, K. Esmaieli

Brunswick mine employs an ore and waste pass system for material transfer. This paper reviews the evolution and performance of ore pass systems at the mine. It presents the range of selected configurations, inclination, dimensions, etc. Select case studies are used to address the influence of structure, stress and materials handling on the longevity of the employed ore passes.

Jan 1, 2008

By Brendan Parker, Tyron Rees, Steven Hart, Abba Manesh, Ian Mcgaffin

"In September 2009, Newmont began the commissioning of a 3 stage crushing and milling circuit at its Boddington Gold Operation in Western Australia. The Boddington ore has been recognized as one of the hardest and most abrasive ores treated to date and this played a pivotal role in the selection of crushing and HPGR technology for this operation as opposed to the more conventional SABC circuit.This paper will examine the scale up from laboratory to pilot plant and full scale operation of the crushing circuit. There have been many challenges to overcome in the first 18 months of operation; however, the HPGRs have in general met design expectations and performance is expected to improve further with ongoing design changes"

Jan 1, 2012

By R. W. Davis

INTRODUCTION CHURCHILL river was named for John Churchill, first Duke of Marl-borough and third Governor of the Hudson&apos;s Bay Company, in the latter part of the 17th century, some fifty years after the ill-fated Danish expedition, led by Munck, had abandoned the site of the now famous seaport of Churchill, as a worthless, cold, disease-ridden country. No other attempts were made to explore the interior until the river basin became a part of the grant to the Hudson&apos;s Bay Company and began to play its part in furnishing the luxury of fine furs to civilized people as it had furnished the necessities of food and dress for untold centuries to uncivilized natives. This was the sole contribution of the region to the economic life of the country for some two hundred and fifty years, until 1926, when the power site at Island Falls was discovered by engineers seeking a cheap power source to make possible the development of the great ore-body at Flin Flon. DRAINAGE BASIN OF CHURCHILL RIVER The river is some 1,325 miles long. Rising in the headwaters of the Beaver river, in east-central Alberta, it flows in an easterly direction across Saskatchewan and northeasterly across Manitoba to Hudson bay, through a remarkable basin of some 115,500 square miles, only 6,000 square miles less than the area of the British Isles. A journey down this river leads one through three distinct belts of country, each vastly different from the others geologically and in surface characteristics. For the first five hundred miles the river flows through a basin of 36,000 square miles of the great central-plains country, which is covered with fertile soil and carpeted in its southern part with prairie grass, which gradually gives way to the mixed forests of poplar, spruce, birch, and jackpine in the northern and eastern sections: About midway across Saskatchewan, bald-headed knolls and ridges begin to make their appearance as the river meets the western margin of the Canadian Shield. Then, for some seven hundred miles, it passes through country underlain by the pre-Cambrian rocks of the Shield, which continue to within one hundred miles of Hudson bay. Here the character of the country again changes to a low, clay plain underlain by sandstone, and through this &apos;clay belt&apos; the river flows between steep clay banks, to empty into Hudson bay.

Jan 1, 1935

By K. Tarr

Acid-producing mine tailings are present at many active and inactive mine sites and pose an environmental liability due to the potential for acid rock drainage. Acid rock drainage originating from a tailings pile, a waste rock pile, or exposed sulfide-rich rock, can cause discoloration and turbidity in receiving waters, and the loading of ions mobilized by the acid can cause a decrease in aquatic flora and fauna, and reduction in the quality of groundwater. The primary cause of acid generation is the oxidation of sulfide minerals, predominantly pyrite and pyrrhotite. Considerable mine tailings are being stored on surface in vast tailings impoundment areas across Canada. In the tailings within this study, from the Sudbury, Ontario area, the sulfide mineral of primary concern with respect to acid generation is pyrrhotite. Different tailings types show varying and progressive degrees of oxidation correlating to their specific sulfur contents. The degree of oxidation is determined by the relative extent to which the sulfides have reacted as well as the depth of oxidation within the tailings. Natural Resources Canada, CanmetMINING is dedicated to research supporting the Green Mining Initiative, a program reducing business risks by demonstrating practices that reduce environmental impacts. In cooperation with the Canada Mining Innovation Council (CMIC), applied research aims to reduce land disturbance, waste volumes, and releases to the environment. By reutilizing tailings from vast impoundment areas as a component in backfill, the potential environmental impact would be lessened considerably, due to the reduced tonnage stored on surface long-term. From an operating perspective, there is a need for supplemental feed for backfill from time to time. The reclamation of old tailings for use in backfill is also driven by the fact that old tailings ponds may not be structurally stable, and it may be more cost effective to remove the tailings than to upgrade the impoundment structure. However it is imperative that these old tailings be fully characterized to determine their suitability for use underground, in order to ensure the long-term integrity of the resulting backfill matrix. A study was conducted to investigate the feasibility of tailings reclamation from old impoundment areas as a significant component in backfill. The materials were first physically and chemically characterized, followed by preparation of samples to determine optimal mix proportions for strength development for both paste and hydraulic fill compliance. It was found that the amount of oxidized tailings included in the backfill material had a profound effect on both the segregation and settling properties of the backfill matrix, as well as the mechanical properties of the samples. The strategies for decision-making, based on the criteria for material characterization, mining plan, and cost effectiveness are discussed.

Aug 1, 2013

By R. Stratton-Crawley, S. W. Wilson

"Inco's Matte Separation Plant is a unique mineral processing facility having no process tailings stream. Each product is a high-grade concentrate with strict assay specifications which are defined by the downstream refining route. The most recent column application in the flowsheet, copper scavenging in the production of a high quality nickel concentrate, is described in detail. Testwork in pilot-scale columns (0.038 m, 0.051 m and 0.10 m in diameter) was used to develop a model of the copper scavenging system. This data was then used to simulate the performance of plant-scale equipment. The relationships thus established were confirmed by a series of plant tests in a 1.8 m diameter column. Column results consistently exceeded conventional cell performance. The modelling was extended to assess full plant production requirements and, as a result, a 2.1 m diameter column was specified for this application. Engineering design for this column is currently underway and the column is scheduled to be commissioned later in 1991.INTRODUCTIONMatte SeparationINCO's Matte Separation Plant is a part of the Copper Cliff Smelter complex near Sudbury Ontario. The flowsheet and the development of column flotation within it have been described previously (Feeley et al., 1987, Wilson et al., 1989). The plant feed is a synthetic Bessemer Matte from the Nickel smelter. This matte is slow cooled to promote grain growth and typically assays 46-52% Ni, 23-27% Cu. These elements are present primarily in sulphide form (Ni3S2 and Cu2S respectively) with some metallic alloy also precipitating from the sulphur deficient matte. Minor amounts of iron, precious metals, and nuisance elements are also present.The matte separation process is, in concept, relatively simple. Following magnetic removal of the metallic alloy from the feed, the flowsheet is designed to float a high grade copper concentrate from the nickel sulphide matrix. A simplified flowsheet of the process is shown in figure 1."

Jan 1, 1991

By R. T. Saxon

Prior to November 1975 there were several failures of front -wheel spindles on large haulage truck s in B.C., attributed to fatigue cracks. Since that time, a non-destructive test program has succeeded in detecting the cracks before catastrophic failure, However, the author regards the failures as just one example of a. general unreliability in large high-strength steel castings and urges the industry to look to forgings for sensitive components of heavy equipment.

Jan 1, 1977