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By Claude A. Jr. Seger

Introduction This paper presents in detailed form the results of settling tests that were published in a few preliminary notes in the April 1949 issue of the Bulletin (p. 166). Carborel is the trade name for sodium carboxymethyl-cellulose and aluminium carboxymethyl-cellulose produced by the reaction of monochloroacetic acid on the alkali cellulose to form an ether. The water-soluble sodium carboxymethyl-cellulose has been known in Europe for several years as sodium cellulose glycolate and has been marketed under several trade names. These cellulose ethers, however, are relatively new in North America, where the name carboxymethyl-cellulose is often abbreviated to C.M.C., or they are referred to as cellulose gum. The particular grade of Carboxel used in the settling tests in the mill of Chesterville Mines, Limited, is the high-viscosity sodium carboxymethyl- cellulose known as Carboxel H.V. It is a white, fluffy powder and is hygroscopic, although not deliquescent. Carboxel solutions in water are colourless, odourless, and resistant to beat and light. They are stable to alkalies, but are precipitated by acids when the pH is reduced below 4.0, and also by solutions of soluble lead, iron, copper, aluminium, and chromium salts. Solutions of Carboxel exhibit the properties of hydrophilic colloids.

Jan 1, 1949

By R. S. Boorman, H. G. Ansell

"Poor separation of lead from a copper concentrate of a major base metal producer was thought to have resulted from copper (0.2-0.4%) in the galena which caused it to float with chalcopyrite. No inclusions of copper mineral were detected which could account for the flotation of galena. The tendency for copper-bearing galena to float with chalcopyrite was confirmed by Hallimond-tube experiments in which the floatability of copper-doped synthetic galena (0.1-0.4% Cu) was approximately four times as high as copper-free galena. The difference in the cell edge (5.9338 ± 0.0003 A, Cudoped galena; 5.9361 ± 0.0002 A, Cu-free galena) indicated that the copper was lattice-bound and did not occur as submicroscopic mineral inclusions."

Jan 1, 1973

By Suzie Nantel

Crystalline igneous rocks, known commercially as granite, are exploited in Quebec f rom more than twenty-five quarries for building, ornamental and monumental purpose$. Quebec is the main Canadian producer of construction granite, accounting for nearly 90 per cent of total production. Jn the last three years, this industry has experienced an important growth due to improved marketing and use of modern equipment in rock-cutting and polishing. Jn /983 a 35 per cent sales increase is forecast. The main rock varieties extracted are the following: porphyritic pinkish grey granite and green charnockite from Riviere-dPierre, mahogany brown granite and black anorthositic rock f rom the Lac Saint-Jean area, fine-grained pink granite from Guenette, coarse-grained brown quartz monzonitefrom SaintA lexis-des-Monts. All these rock types occur in the Grenville tectonic province whereas a medium-grained, light grey granite, Devonian in age, is extensively being quarried in the southern part of the Appalachians. In the Superior province a greenish black diabase and a deep red granite are extracted. Search for new varieties and deposits is actively being carried out by prospectors and by the minis/ere de /'Energie et des Ressources du Quebec following growing demand for granitic and gabbroic rocks as dimension stone.

Jan 1, 1984

By Carl Pelletier

The Sigma-Lamaque Complex is considered a lode-gold deposit characterized by narrow vein structures, which have been mined historically by underground methods. In addition to the narrow vertical structures, mining also took place on horizontal veins, ?North Dipper? veins and dykes mineralized with sub-horizontal veins and stringers. Over the 60 + years of production, mining took place to a depth of 1.8 km. The upper portion of the deposit was considered all but exhausted, when viewed from an underground mining perspective. The year 1998 is considered a turning point for the Complex when a small open pit was mined at Sigma. The resource evaluation methods used underground were applied to surface mining, which allowed small pits to be mined. The resource evaluation method considered only the narrow vertical structures and was not well adapted to open pit mining. As a consequence, resources were consistently under evaluated. It became clear that a new geological approach was necessary to more accurately define resources (i.e., what was being mined). In order to integrate all characteristics (geometry, mechanics and chronology) of this complex lode-gold deposit, a new geological model was proposed. Due to this new approach, dating to February 2000 and updated in December 2000, the reserves evaluated in the first 180 meters now stand at 15 million tonnes @ 2.61 g/t Au (1,265,350 oz). Those reserves cover an east-west corridor extending 1,500 m by 750 m.

May 1, 2001

By Lucas van Latum

A Model for Safety Swiss cheese metaphor of safety layers Image »Multiple layers with independent, often transient failure modes »For a loss to occur, all layers must fail independently and simultaneously ??Latent? failures are due to inherent system flaws ??Active? failures are due to unsafe acts

May 1, 2011

By R. Fukuzawa

"The objective of this research is to evaluate the magnitude of carbon prices required to drive process development and innovation for the global nickel industry in a direction that tackles the multifaceted sustainability challenges that the industry faces, including air pollution reduction and greenhouse gas abatement. The results suggest that the currently considered carbon prices are not sufficient to drive innovations in processing methods or upstream pollution prevention. The co-benefits of climate change mitigation and pollution prevention cannot be readily realized under climate change policy alone. Increased coordination between climate change policy and performance-based environmental legislation is necessary. INTRODUCTIONNickel is an important metal in our modern society as it is used in stainless steel, alloys, electroplating and rechargeable batteries, all of which are integral to our economic growth and development (Eckelman, 2010).However, nickel production is energy intensive and therefore susceptible to emerging climate change policies, which may lead to production curtailment and/or increased unit costs of production unless changes in efficiency or energy sources are made (Mudd, 2010). The industry is faced with multi-faceted constraints: future technology must not only deal with metallurgical, financial and environmental constraints but also promote low energy and low carbon practices. This presents a challenge for this industry where technology innovation, development and commercialization are often lengthy, risky and costly processes (Imrie, 2006).Climate change is one of the many challenges faced by our society. Others include other pollution to air, water and land, resources shortage and economic development. From a policy perspective, it is important to balance multiple and often competing needs in an integrated manner. It would require some levels of trade-off in order to maximize the overall effectiveness but also to ensure that one policy does not undermine other policy objectives.The aims of this study are to evaluate how developments in climate change policy would affect the nickel industry in the context of existing environmental regulations and how the industry could respond under these constraints."

Jan 1, 2012

By Michael E. Charles, Jaroslav J. Vocadlo

"The hydraulic transport of solids through pipelines can have many advantages over other modes of transport. Numerous successful applications both within plants and over longer distances have demonstrated the technical and economic feasibility of slurry pipelining. Solids successfully transported include kaolin, coal, iron ore, gilsonite and limestone, and others, such as sulphur and potash, are likely to be transported in Canada in the near future. However, though the technology of solids pipelining is quite advanced the underlying principles have not yet been formulated past the semi-empirical stage. The main objective of this paper is to present a discussion of the important technical and economic considerations in the design of so lids pipeline systems by reference to typical data. The Worthington slurry pumps and pilot facilities are briefly described."

Jan 1, 1972

By Y. Mercadier, M. Ait-Ali, M. Dostie

"This paper presents the results of an analytical study to assist in the design of blast furnace tuyeres, including a prediction of the heat transfer process.IntroductionA blast furnace tuyere must be made of a material which must con serve its geometric and structural integrity in the environment of the fire-ball of the furnace. It must be cooled by a fluid forced through its internal cavities in such way as to keep its maximum temperature below the allowable limit. The prediction of the convective heat transfer coefficient inside the tuyere is of great importance in the design of new tuyeres with increased service life. We have developed a computer program which can predict the convective heat transfer coefficient for two-phase flow. This paper shows how the program work s and how it can be used for the numerical simulation of tuyeres.To simulate the h eat transfer conditions in water-cooled tuyeres, one has to predict:a) The heat flux (radiation and convection) generated by the combustion gases. This was evaluated using the single-zone gas-furnace model. This model yields results which are of the right order of magnitude. A more fundamental study of radiation heat transfer based on combustion and gas concentration s will be reported in a future publication.b) The local convective heat transfer coefficient at all points with in the tuyere.Prediction of the Convective Heat Transfer CoefficientTo calculate the convective heat transfer coefficient for refrigerant stream, semi-empirical correlations developed by the nuclear industry were adopted. These correlations permit us to analyze the entire range of the convective boiling range, as shown in Table 1. Our first attempt, with a single-phase flow correlation, has shown the need to take nucleate boiling into account."

Jan 1, 1982

By T. C. Rao, Deb Kanungo

"The results of tests carried out on a 3-in. hydrocyclone have shown the linear relationships that exist between: (1) the flow-rate of water in the feed to and the overflow product from the cyclone; (2) the flow-rate of solids in the feed to and the underflow product from the cyclone. The underflow size distribution of an operation has been found to be linear and its usefulness in evaluating particle distribution in the cyclone has been discussed. Effects of design and operating variables on the above relationships have been discussed. The performance of this 3-in. hydrocyclone has been compared with that of a 20-in. cyclone, the results for which are available in the literature."

Jan 1, 1973

By Lawrence D. Hoy, Armand Savoie, Pierre Trudel, Ghislaln Tourigny, Robert Crépeau, Lao Kheang

"Recent fluid inclusion and stable isotopic studies in the Bousquet mining district have identified spatial and temporal trends in mineralization temperatures and isotopic compositions of vein forming fluids. These studies indicate that mineralizing temperatures were lower during sterile vein formation (T=200-300°C) than during auriferous vein formation (T = 300-400°C), and that 8 80 values of minerals in sterile veins are lower by 1-3 %o than in associated auriferous veins. In addition to these small differences in 8 80 within individual mineralized zones, a trend of increasing 8 80 values of vein minerals is identified from west to east across the district, with 8 80 of vein minerals increasing by4-6%o. Quantitative evaluation of potential causes of the observed oxygen isotopic shifts suggests that the best explanation for these trends is the derivation of the mineralizing fluids from an isotopically inhomogeneous terrain in which the fluid isotopic compositions are controlled by the isotopic compositions of the host lithologies due to high rock/water ratios in these source terrains. This inhomogeneous source terrain is interpreted as consisting of the Blake River Group volcanics (low 8 80 component) and the adjoining Kewagama and Cadillac Group sediments (high 8 80 component).The genesis of the hydrothermal fluids is attributed to crustal heating during metamorphism, with the fluids representing metamorphic dewatering products and/or fluids incorporated during deposition and burial of the host lithologies. Ductile deformation of the fluid source regions impeded fluid migration during metamorphism; the ultimate release of the mineralizing fluids is attributed to the penetration to depth of vertical structures (fault and shear zones) during brittle deformation of the crust under waning metamorphic conditions. Release of fluids caused by this puncturing of the closed hydrologic source regime produced a localized zone of lowered pressure, drawing fluids from adjacent lithologies toward the fault zones, feeding further hydrothermal fluid upwelling. Au mineralization resulted from chemical processes related to cooling of the hydrothermal fluids and/or interaction with lithologies encountered during fluid migration; the level of crust at which Au deposition occurred likely migrated upward with the thermal anomaly caused by hydrothermal fluid upwelling, eventually reaching the level of current exploitation. Cessation of fluid flow along the vertical structures is attributed to inadequate recharge of the hydrothermal systems as fluid contents were depleted in the lithologies proximal to the vertical structures and/or sealing of the structures by mineral deposition."

Jan 1, 1990

By K. Soldenhoff, M. Fainerman-Melnikova

The use of strong base resins for uranium recovery is severely affected by the presence of chloride ions in solution. In areas where high-quality process water is not readily available, the use of saline water would extend the potential application for ion exchange in uranium processing. This study presents measurements of uranium uptake, using a wide range of commercially available weak base anionic exchangers, from solutions with chloride concentrations ranging from 2.5 to 22 g/L Cl. Out of 14 weak base anionic resins tested, 3 were identified that were not severely impacted by the presence of chloride and significantly outperformed a gel strong base resin typically used for uranium recovery in high-chloride environments. The uranium loading was sufficiently high for the consideration of development of the application of uranium recovery from uranium ores leached with seawater.

Jan 1, 2012

By W. H. MacLean, S. Liaghat

The Key Tuffite is a thick (0.3 m to 6 m) and laterally extensive (-10 km) cherty, sulfide-bearing tuff unit in Archean greenstones in the Matagami mining district in northwestern Quebec. It lies at the contact of the Watson Lake Group and overlying Wabassee Group volcanic rocks, and is host to major Zn-Cu volcanogenic massive sulfide deposits. The tuff component is highly altered and its volcanic precursors are not identifiable by petrographic means. The tuff is mixed with a volcanic exhalative component comprising chert, carbonate and sulfides (pyrite, pyrrhotite, and minor sphalerite and chalcopyrite). The normative mineral composition of the Key Tuffite is 33% quartz, 28% sulfides, 16% sericite, 8070 carbonate, 6% chlorite and 9% other minerals. In the vicinity of the Bell Allard and Orchan mines, the precursor tuff components are identified using immobile major and trace elements, as Watson Lake tholeiitic rhyolite (Zr/Y = 1.5 to 3.5, LaN/ybN = 1.7 to 2.8, SiO2 = 72.5 ± 1.2 wt %, and Wabassee calc-alkaline andesite (Zr/Y = 9, LaN/YbN= 4 to 8, SiO2 = 56% to 65%). Immobile element computation techniques were used to calculate mass additions and losses in the conversion of the tuff to the Key Tuffite. Average net amounts of FeP3 (27% total iron), Si02 (14%), Cao (8%), S and K2 (+ 2%), were added, Nap was removed (-2.8%), and MgO was over-all unchanged. Total net mass change was +63%, which comprises mainly exhalative additions, but also includes changes owing to hydrothermal alteration of the tuff component.

Jan 1, 1992

By F. Rashchi, N. Naseri Joda

Recycling of electronic wastes is an important subject both from an environmental point of view and also the recovery of valuable materials. In this research, PC board scraps were leached to recover Cu, Ag, Au and Pd. Due to the high cost of the shredding process and to avoid secondary pollution from odors and dusts, board scraps were cut into 5X5 cm2 pieces. To determine the most effective leachant, aqua regia, nitric acid, hydrochloric acid, ammonium persulfate and potassium persulfate were tested. The effect of the leaching parameters, the leachant concentration, temperature, leaching time and liquid to solid ratio were studied and optimized using response surface methodology.

Jan 1, 2011

By M. Jorgensen, I. Markland, D. Shuck

"The McLaughlin Mine owned by Homestake Mining Company is located 70 miles northeast of San Francisco in California's coastal range. The mine began operations in February of 1985. The mill currently processes 3,000 short-ton per day of sulfide ore that has an average grade of 0.15 ounces of gold per ton, plus another 3,000 tons per day in a newly completed oxide circuit. Annual production from the mine totals over 200,000 ounces.The sulfide ore extraction process involves three basic steps, grinding, oxidation of sulfide minerals in an autoclave, and cyanide leaching for recovery of gold in a carbon-in-pulp circuit. This process, which incorporates a new technology where oxidation of sulfide minerals is conducted prior to cyanide leaching to facilitate gold recovery, was successful from start-up. However, limitation in the grinding mills initially limited sulfide tonnage throughput.This paper discusses modifications made in the grinding circuit, both mechanical and operational, to resolve it deficiency. The SAG mill, in particular, was unable to achieve design tonnage initially and proved to be most troublesome. Complications occurred due to the hardness and variability of ore being processed, short component life, and a lifter /liner arrangement that had to be tailored to the particular circumstances at McLaughlin. IntroductionHomestake Mining Company's McLaughlin Mill, located in northern California, was designed to process a refractory gold ore at a rate of 3,000 tpd to render the ore amenable to cyanidation. Seven years transpired between discovery of the near-surface ore body in 1978 and the February, 1985 plant start-up. Development of the McLaughlin mill and open pit gold mine hinged on the use of autoclave technology to achieve design recoveries."

Jan 1, 1991

By Carol A. Pilon

"IntroductionRECENTLY, the Saskatchewan Research Council (Saskatoon ) marked the completion of one of its coal-related projects with the publication of the Bibliography and Index of Coal in Saskatchewan and Adjoining Provinces and States, hereafter referred to as the Bibliography and Index of Coal. Over a two-year time period, literature was surveyed and indexed and bibliographic data were compiled using a computer-assisted information retrieval system called FAMULUS. The final publication contains 1150 bibliographic references, which are cross-referenced by six indices.The project was initiated in September 1974, in support of Saskatchewan's Coal Resources Evaluation Program , an ongoing research program sponsored by the Department of Energy, Mines and Resources (Ottawa) and the Province of Saskatchewan. This program places emphasis on such areas of concern as the occurrence of deposits, chemical and physical properties, calculation of reserves and computer-assisted applications for the evaluation of lignite resources in the Province. Attention is also given to aspects of geophysical exploration, mining conditions and economics, by-products and the transporting of lignite. These are the subject areas .covered by the Bibliography and Index of Coal.The over -all objectives of the literature indexing project may be enumerated as follows: (1) to build a specialized resource library by surveying established public and specialized libraries, and commercial data bases; (2) to enter library data into the FAMULUS information retrieval system, to be used to generate bibliographies and indexes, and to retrieve information by the use of specified searching techniques; (3) to make this library data available to interested persons."

Jan 1, 1977

By B. D. H. Knights, N. B. du Preez

The recovery of the economy of the Democratic Republic of Congo has allowed for the rapid increase in production of copper from this region, while the increased price of cobalt continues to support the recovery of that country’s economy. This has enabled the modernization of the process technology used, particularly the change from direct electrowinning of copper to solvent extraction-electrowinning. With this change has come a variety of technical challenges in optimizing the recovery of cobalt from these sources. In this paper, we discuss aspects of the flowsheets for the production of cobalt from the ores of the DRC and Zambia, highlighting the technological improvements that have been made. Following this description of the practice, we assess the challenges of further improving the recovery and purity of cobalt from these sources. INTRODUCTION The African Copperbelt (Figure 1) is by far the biggest producer and holds the greatest reserves of cobalt (Sheed, 2015). However, the ores of this great mining region are extracted primarily for their copper content, and cobalt is a by-product. The ratio of copper-to-cobalt is between 6 and 20 to 1, with the ores from the DRC richer in cobalt than those from Zambia. The overall supply of cobalt, shown in Figure 2, is increasing due to an increase in demand for its use as a battery material. Cobalt is used in superalloys, hard metals, pigments, catalysts magnets, tyre adhesives, lithium-ion rechargeable batteries, and wear-resistant coatings, amongst others. Although these generic categories persist, Figure 3 shows how the relative usage of cobalt is changing due to the uptake of electric vehicles in China and Europe. Cobalt is a key element in lithium-ion batteries, and because it is widely anticipated that electric vehicles will be legislatively encouraged, it is anticipated that the demand for cobalt will rise. This anticipated increase in demand resulted in an increase in the price for cobalt, to which suppliers responded over-eagerly, and the price has dropped dramatically in the first few months of 2019, as shown in Figure 4. However, there is a clear cycle of price peaks in cobalt’s history.

Jan 1, 2019

By Gwenaële Petit, Ulan Massimkhanov, Gilles Joubert

For its Zuuvch Ovoo uranium deposit in Mongolia, Badrakh Energy (partly owned by Orano Mining) is working on the prefeasibility study for exploitation by ISR (in situ recovery). As part of this project, Orano built a 2-cell (each cell is constituted of one producer well located in the center and surrounded by six injection wells in an hexagonal pattern) and a processing pilot plant that will be used to demonstrate the operability and economic viability of an ISR process. Another main objective of this pilot trial is to demonstrate the ability of Orano’s modeling tools to predict the ore behavior under given leaching conditions. To model uranium production by ISR, Orano uses HYTEC, a reactive transport computational software, which was adapted for its existing operation in Kazakhstan (Katco) to predict uranium recovery and reagent usage based on operating conditions. In order to perform similar simulations for this new deposit, Orano engaged in a comprehensive program including ore sampling, detailed characterization, and metallurgical testwork. The mineralogical conclusions were used to prepare a simplified geochemistry for the ore, in particular carbonate and reactive clay grades, uranium mineralization and penalizing elements such as pyrite. Then, bottle roll leach tests were used to characterize dissolution kinetics for smectite clays. Eventually, column leach test results such as pH, free acid, and uranium recovery were modeled on HYTEC to improve the fit of some of the dissolution kinetic parameters. Parameters fitted using metallurgical test work results will now be used as inputs for predictive model at the pilot scale, in order to anticipate operational results and help with operating decisions for production ramp up.

Jan 1, 2020

By A. J. Paul Laprairie

"ADVANCE planning of mining methods, from the first development openings to stope layout and pillar recovery, has long been accepted as a normal method of operating a mine. Recently, mine managers have become increasingly aware that advance planning of cost and accounting controls can also be considered a normal method of operation. The use of such controls is wide-spread in manufacturing industries. In mining, the gold mines of South Africa have pioneered, with marked success, in this field and have been closely associated with most of the research and field work in accounting control. Canadian mine managers are also beginning to realize the advantages of using planned costs. The control procedures which subsequently have been introduced at various mines have come to be known by such names as ""Responsibility Costing"" or Budgetary Control"".Budgetary control, the term used in this paper, is based on the concept of decentralized authority with centralized control. ;The control is achieved by measuring results against yardsticks which are in the form of budgets or standards. Bud-gets are made for the future activities of each possible operation as planned by the department head, and attention is directed to variations from this plan. Furthermore, the control process charges to each operation only those costs which are incurred directly for that operation, and which can be controlled by the person in charge. Thus, budgetary control relates results to the officials responsible for those results. Expenditures are analyzed according to the organizational structure of the mine and the people who run it, and not according to production processes."

Jan 1, 1960

By D. O. Tansey

This paper will describe the mechanisms involved in delay blasting and how they are applied with the use of D.S.B. It will examine the control of potential damage resulting from detonations, and show how good fragmentation and efficient recovery of this material blasted can be achieved.

Jan 1, 1979

By M. Muinonen, A. R. Barnes, R. Pandher, M. J. Lavigne

Over the past three years, Ring of Fire chromite ores have been tested extensively at both the bench scale and pilot scale at XPS Consulting and Testwork Services. Following bench scale testwork, two smelting campaigns were completed using a 300 kW DC arc furnace on different chromite deposits from the Ring of Fire. A ChemSheet model was developed to aid in the design and optimization of the recipes, and its predictions were confirmed with both the bench scale and pilot scale tests. A total of 7.5 tonnes of chromite ore was smelted at XPS. The results of the testwork demonstrate excellent reducibility for the ores tested with good reduction kinetics when compared with South African chromites.

Jan 1, 2014