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By Akiyoshi Horiuchi, Manabu Kanno, Shigeki Sato, Taro Aichi

"AKITA ZINC Co., Ltd. (Iijima Zinc Refinery), jointly owned by DOWA METALS & MINING Co., Ltd.(DMM), has used the company’s own hematite process for iron control since the beginning of operations in 1971. The hematite process consists of reductive leaching with SO2 gas and iron removal in autoclaves by high temperature hydrolysis. This process enhances not only zinc recovery but also the recovery of gold, silver, copper, lead and rare metals, which is carried out at another DOWA metallurgical plant. All by-products produced in the hematite process are marketed and sold. This paper presents an overview of the hematite process and the recent process improvements made.INTRODUCTION DMM carries out mining and smelting activities for precious metals, PGMs, rare metals and base metals such as copper, lead and zinc. It owns KOSAKA SMELTING & REFINING, producing copper and lead, and the AKITA ZINC Co., Ltd. (AZC) in Akita Prefecture. DOWA is a specialized smelting company which has established a metallurgical complex for copper, lead and zinc, including a recycling business. AZC was established in 1971 at a production capacity of 72,000 t/y zinc; it is jointly owned by DMM and five other non-ferrous metal companies. AZC has increased its capacity continuously and now produces 210,000 t/y of zinc. Figure 1 shows the changes in zinc production and capacity at AZC."

Jan 1, 2016

By R. M. Clowes

"As part of LITHOPROBE's multidisciplinary earth science research program to understand the evolution of the North American continent, studies have been undertaken in a number of key areas in Canada. In the Trans-Hudson Orogen of Manitoba and Saskatchewan, LITHOPROBE results require re-evaluation of tectonic models related to its origin. In the Abitibi greenstone belt of Quebec and Ontario, results indicate a more complex evolution for the southern Superior province, one that links with the development of gold and massive sulphide deposits. As part of the program, the seismic reflection profiling method is being adapted for the mining industry. Three examples demonstrate the subsurface information that can be obtained. In Noranda, the base of the volcanic Blake River group is imaged and reflectivity is tied to geology through well logs; in Matagami, the zone of mineralization is shown to be downdropped along a majorfault; in Sudbury, a new structural model is developed, one that shows marked asymmetry at depth and indicates that some ore-bearing units on the margins of the igneous complex may be repeated at depth. IntroductionLITHOPROBE is Canada's national, collaborative earth science research project, established to develop a comprehensive understanding of how the North American continent has evolved. Ten transects, or study areas, were chosen to investigate pivotal geological features to their deep lithospheric roots. They span the country from the Pacific to the Atlantic Oceans and from the U.S. border to the Yukon and Northwest Territories, and geological time from four billion years ago to the present. A multidisciplinary approach, which is spearheaded by seismic reflection techniques, is essential to developing complete interpretations and outstanding scientific results. LITHOPROBE also has pioneered the use and demonstrated the value of using reflection technology to determine subsurface geology in mining camps.This paper provides an overview of the transects and their significance for the tectonic evolution of North America. Two specific examples demonstrate how we detennine present three-dimensional lithospheric structure and past geotectonic processes which formed it. The application of the reflection method to imaging complex structures in ""shallow"" crystalline rocks has been developed with funding and other support from the mining industry and provincial geological surveys. Sustaining funds, however, are derived from the Natural Sciences and Engineering Research Council and Geological Survey of Canada. Emphasis has been placed on developing deeper penetrating tools for exploration of deeply buried, but economically retrievable, mineral resources near existing mines, where an expensive infrastructure already is in place. Three examples, Rouyn-Noranda in western Quebec, Matagami in northwestern Quebec and Sudbury in northeastern Ontario, illustrate these developments."

Jan 1, 1994

By Peter N. Blakey, Jean-Paul Paquette, Barton A. Thomson

"FROM THE BEGINNING OF THE PIT, it was known that the surface mining method had a projected life of about ten years, and that the ore extended to depths recoverable only by underground mining. When serious consideration was given to underground mining in 1968, it was realized that tremendous advantages could be gained by starting the underground mine as early as• poss1ble. These included: 1. The availability of underground ore for grade control, which would become more difficult as the pit deepened. 2. The need to develop new systems, equipment and skills to take full advantage of the technological revolution in underground mining. 3. Early knowledge of rock behaviour through trial mining on a small scale prior to finalizing plans for major blocks. In addition, the pit would be available to guarantee the mill supply if problems were encountered. 4. With sufficient time and early mining experience a much better job could be done on all mine planning. Because ample reserves of economic underground ore were virtually assured, the desired underground mining capability became a function of two restraints: first, the time required to excavate and construct the permanent headframe, shaft and ore-handling facilities necessary to handle large volumes of stope ore; second, the time for lateral and stope development on at least one level which would normally follow shaft sinking. The decision made was to move immediately on the permanent hoisting installations and at the same time embark on the planned ramp from surface, which would allow much stope preparation to be completed prior to .bringing the shaft on stream. Both projects were placed on an urgent basis early in 196S' and the following decisions made shortly thereafter."

Jan 1, 1974

"This paper describes an alternative method of vehicle control which uses a micro-processor to control the field current and armature voltage concurrently. The field tests carried out and the conclusions drawn from the basis of the paper.IntroductionIt is generally accepted that the main obstacle to a greater use of electric vehicles is the relatively poor range and performance when compared to alternatives such as diesel and petrol-engine vehicles. Much effort has been applied to the problem of increasing the energy storage density of batteries and considerable improvements are now being reported.Improvements in the efficient use of the stored energy, although unlikely to achieve the necessary increase in range and performance for a widespread acceptance of electric vehicles, can nevertheless make a useful contribution. Because the improvement in efficiency is achieved by a reduction in losses, it follows that the temperature rise in drive-train components is reduced. These advantages, coupled with the increasing cost of energy, make improvements in the efficient use of the stored energy desirable, if not absolutely necessary. To achieve this with the large and rapidly varying loads encountered during the operational use of a vehicle will require a more flexible system of control than that provided by the current limit. This paper describes an alternative method of control which uses a micro-processor to control the field current and armature voltage concurrently.The value of these parameters is selected to supply the power demand at the motor shaft, with the minimum losses in electrical transmission, thus increasing the efficiency with which the stored energy is used."

Jan 1, 1982

By M. Tardif, F. L. -Lavoie, M. Ruel

"In mineral processing, it is often very difficult to reliably measure several key operation variables. The harsh environment and high temperature encountered in pyrometallurgy processes lead to some difficulties when selecting the instruments, valves and actuators. If an important variable cannot be measured or manipulated adequately, controlling it can really become a big challenge. Sometimes, it is simply impossible to find the perfect equipment for the task. To help overcome these difficulties, a different approach is required. This approach will not correct the inherent problems related to the instruments and valves, but will cope with these problems. This article will demonstrate how modern process control techniques can be used to solve complex problems while remaining easy to implement. In this article we will described how soft sensors and multivariable fuzzy logic control were implemented at Koniambo Nickel to stabilize the furnace feed and allow for safe and reliable operation of an 80 MW DC arc furnace.INTRODUCTION Process Overview The process plant at Koniambo Nickel SAS is located in the North Province of New Caledonia, 310 km north of Noumea. The nickel-bearing ore is mined in the nearby Koniambo massif. After being screened and crushed, the ore is transported to the processing plant using a 12 km conveyor. After stacking in two blending piles, the ore, containing 2.3% nickel, is fed to the processing plant where it will go through the NST process (Nickel Smelting Technology) before being sent to refining and shotting. This article will focus on the improvement to control of the NST processes. The first steps of this process consist of milling the ore and removing all moisture through calcining (Figure 1)."

Jan 1, 2017

By Joseph Carlston

With environmental regulations continuing to restrict the discharge of phosphorus from wastewater treatment facilities, traditional methods of phosphorus removal are proving inadequate. To achieve the phosphorus control necessary, a new coagulant used for phosphorus removal, cerium chloride, has been studied in several municipal and industrial wastewater treatment facilities that must meet a phosphorus discharge limit of 0.5 mg/L or lower. These studies demonstrated the high phosphorus removal capabilities of cerium chloride, with the results illustrating the ability for cerium chloride to reduce phosphorus to low concentrations in the effluent using a lower volume of product as compared to traditional coagulants, such as ferric chloride. This reduction is due to the unique ability of cerium chloride to remove phosphorus as cerium phosphate, whereas iron- and aluminum-based coagulants rely on adsorption and co-precipitation.

Jan 1, 2014

By Jacque Turgeon, Gontran Foy

"The Mineral Research Centre of the Quebec Department of Energy and Resources has worked extensively on the development of a dry process to extract pure mica flakes from a phlogopite ore. The liberation of mica from the gangue is effected basically by impact crushing, and the ground ore is screened into several fractions, each having a fairly narrow range of grain size. Each sized fraction is then fed to an air separator where heavy grains are separated from light flaky grains. Heavy fractions are returned to hammer mills where gangue minerals are ground finer and blocky mica particles are exfoliated. A second stage of screening is performed and each fraction is sent to an air separator. This sequence is repeated until mica products are virtually free of gangue. These different fractions are then treated in a cage mill in which mica flakes undergo a more orderly exfoliation along cleavage planes. The ground mica is again submitted to a final screening stage, after which each fraction constitutes a final commercial product.This process permits the recovery of about 70% of the mica contained in the ore. The over-all process will be described along with technical details of each unit operation. Recent work on a wet grinding method to produce very fine mica will also be discussed.IntroductionRecords of production of mica in Quebec date back to 1886. Production has been more or less continuous since that time, with peak activity during the war years. Production was interrupted in 1966, but started again in 1972 when Marietta Resources and Laviolette Mining and Metallurgical Corporation started their joint operation in Canton Suzor, northwestern Quebec. Mica deposits of more or less importance exist in different parts of Quebec, of which three have attracted attention in recent years: the Canton Suzor deposit, the Canton Lamy deposit and the Canton Chasseur deposit. The Suzor orebody was first identified by Carl Faesler in 1936, who described the rock as ""brown biotite in flakes half an inch in diameter, with interstitial augite, apatite and feldspar""."

Jan 1, 1982

By F. Awotwe-Appiah, P. Koshy, J. Dankwah, J. R. Dankwah

This research investigates the generation of an effective carbonaceous material from waste ‘pure water sachets’ and their subsequent utilisation as reductants for the reduction of the Opon Mansi iron ore. Composite pellets of Opon Mansi iron ore and pulverised carbonaceous material generated from waste pure water sachets were heated from room temperature to 1200 °C in a gas fired furnace for seventy minutes. The reduced pellet was analysed chemically for its oxygen and carbon content using a LECO Oxygen/Nitrogen and LECO Carbon/Sulphur analysers, respectively. It was observed that nuggets of metallic iron were readily produced with the carbonaceous materials acting as an effective reductant and source of chemical energy. XRD analysis of waste ‘pure water sachets’ revealed that the polymer was semi-crystalline with peaks that were identical to those of high density polyethylene (HDPE). Gas emission behaviour of the iron ore-PWS pellet was studied in a horizontal tube furnace at 1200 °C using an infrared gas analyser; the results revealed an exhaust gas rich in the reducing gases CO and CH4 along with CO2.

Jan 1, 2015

By Robert A. Gault, T. Scott Ercit, Mehmet F. Taner

"Abstract -Vanadium mineralization occurs in oxide-rich horizons within the layered gabbro zones of the upper parts of the Bell River Complex, Matagami, Québec and the Lac Doré Complex, Chibougamau, Québec. The vanadium-rich horizons are well defined on the ground and in aeromagnetic surveys by their high magnetic susceptibility; consequently, magnetic susceptibility can be an indicator of vanadium mineralization. The main oxide minerals are ilmenite and titanian magnetite, containing 20% to 70% of volume and the ratio of titanian magnetite to ilmenite is relatively constant, ranging from about 1:1 to 2:1. Their sizes are less than 5 µm to greater than 1 mm to 2 mm, occurring as coarse- to medium-grained subhedral crystals intergrown with cumulate silicate minerals (plagioclase, pyroxene, etc.). Electron microprobe analyses indicate that the ilmenite grains are mineralogically and compositionally homogeneous and have low V contents (average 0.18% equivalent V2O5). In contrast, the titanian magnetite grains are inhomogeneous, consisting of trellisworks of ilmenite lamellae in Ti-poor, V-rich magnetite [less than 2 wt% TiO2, and 1.41% equiv. V2O5 (1.16% V2O3) for 20 analyses]. Thus, the magnetite is the principal ore mineral of vanadium; it hosts vanadium in the form of V3+, not V5+, as is commonly and erroneously reported. We have also devised a flowchart for the beneficiation of vanadium-titanium ores. Sommaire - La minéralisation de vanadium se trouve dans des horizons riches en minéraux oxydés de la partie supérieure des zones de gabbros lités des Complexes de la Rivière Bell, Matagami, Québec et du Lac Doré, Chibougamau, Québec. Des horizons riches en vanadium ont été bien définis sur le terrain et dans les levés aéromagnétiques par leur susceptibilité magnétique élevée; conséquemment, la susceptibilité magnétique est l’indicateur directe du contenu en vanadium. Les principaux minéraux oxydés sont l’ilménite et la magnétite titanifère, contenant 20% à 70% du volume et le rapport de magnétite titanifère à ilménite est relativement constant, allant d’environ 1:1 à 2:1. Leur dimension varie de 5 µm à plus grande que 1 mm à 2 mm, apparaissant sous forme de cristaux subidiomorphes, de grains grossiers à médiums, intercroissant avec la gangue silicatée (plagioclase, pyroxène, etc.) de la texture de cumulat. Les analyses à la microsonde électronique montrent que les grains d’ilménite sont minéralogiquement et chimiquement homogènes avec un faible contenu en V (moyenne 0.18% équiv. V2O5 ). Contrairement, les grains de magnétite titanifère sont hétérogènes, contenant des lamelles d’ilménite en "trellisworks"; ces grains sont pauvres en Ti et riches en V pour la portion magnétite de la magnétite titanifère [surtout contenant moins de 2 wt. % TiO2, et en moyenne 1.41% équiv. (1.16% V2O3) pour 20 analyses]. Ainsi, la magnétite est le principal minerai de vanadium; elle renferme du vanadium sous forme de V3+ et non de V5+, tel qu’il a été communément et à tort rapporté. Nous avons aussi défini un "flowchart" pour la bénéficiation des minerais de vanadium-titanium."

Jan 1, 1998

By Raja V. Ramani, Sukumar Bandopadhyay

"The dispersion of diesel contaminants into the mine atmosphere is a variant of general class of diffusion-dilution problems relevant to underground mining practice. The equipment operations in underground mining are characterized by different activities with different time duration s, i.e. varying duty cycles. Therefore the volume and quality of diesel emissions and consequently, instantaneous concentrations are quite variable. Design of mine ventilation systems under these conditions becomes complex. In this paper, the development and use of mathematical models of mine production system, the engine exhaust air quality and engine exhaust transport in the design of ventilation system are discussed.IntroductionThe turbulent diffusion of suspended matter in an atmosphere is not only a topic of considerable intrinsic interest to the mathematical physicist and meteorologist, but also a problem of great practical interest. Release of particulate matter into the atmosphere at large has created o ne of the acute problems of the present day. Pollution of environment by industrial and domestic smoke, fumes and grit is widespread and has necessitated extensive studies in order to determine the concentration and distribution of pollutants in various areas. Pollutants discharge from stacks, whether chemical or radioactive, give rise to similar, but more localized, problems. The laws which govern turbulent diffusion in the atmosphere are also applicable to the study of the diffusion of toxic gases and the deposition of radioactive dust from nuclear explosion.The dispersion of diesel contaminants into the mine atmosphere is but a variant of a general class of diffusion-dilution problems relevant to underground mining practice. Most of the mine air pollutants, such as respirable dust, methane, diesel exhaust, and blasting fumes are produced in the face areas and haulage ways. Understanding of their dispersion in the mine airways is important to calculate their concentrations. In this paper, the development and use of mathematical models of mine production system, the engine exhaust air quality and engine exhaust transport are discussed. The over-all objective of this research effort is to evaluate the impacts of dieselization on production and ventilation systems and to aid in mine planning and design, as shown in the flow model in Figure I."

Jan 1, 1983

By J. Baz-Dresch

"The most cost-effective method of placement of the high strength fill used in the Cannon Mine' s overhand cut-and-f ill bench stopes was determined to be truck haulage. Constraint s imposed by the mine layout dictated the use of a truck which could dump its load in a fifteen-foot high drift. The Dux Teledumper truck was selected as the most suitable unit for this application based upon operational and maintenance parameters which included a telescoping, tilting dump box; large load capacity; and robust construction. Development of the truck continues through the cooperation between the manufacturer and user. INTRODUCTIONThe Cannon Mine is situated in the centre of Washington state, approximately midway between the cities of Spokane on the east and Seattle on the west. The mine complex is located three block s south of the Wenatchee city limits at the eastern base of the Cascade Mountain range.Asam era Minerals (U.S.) Inc., with 5I% ownership, operates the Cannon Mine. Breakwater Resources, Ltd. holds the remaining 49%.Annual paroduction is 520 000 tons per year, presently on a 21-shift per week operating schedule for both the mine and the mill.All production is presently won by overhand bench stoping with backfill. Stoping starts with 15-ft high by 24- or 30-ft wide sill cuts driven above and below a stope block . A drop rai se and slot are used to open a bench which is then slabbed toward the open slot. Truck-placed backfill is dumped into the mined - out stope from the upper sill cut. This stoping sequence is repeated until the top of the ore block is reached . The top sill cut is then tightly filled with backfill to minimize subsidence and to provide adequate roof support during extraction of the pillars.Mining equipment consists of hydraulic drills and rubber-tired, diesel scoops and trucks."

Jan 1, 1989

By Helen Morrison, Chris Staun, James Vaughan

"Mercury is introduced into the Bayer refining process as a trace element in bauxite. During the digestion stage, a portion of the mercury is extracted which partitions between the flash tank off-gas, vapour condensate and bauxite residue streams. A technology or treatment that stabilises mercury in the solid phase during digestion would prevent environmental management issues that may arise from the presence of mercury in condensate and non-condensable gases. This study examines the effect of process additives on the deportment of mercury under Bayer digestion conditions. Bauxite digestion experiments were conducted in batch autoclaves in the presence of additives. Process liquor was analysed for mercury content using a thermal desorption technique. Pyrite and copper hydroxide were evaluated for their suitability as additives.INTRODUCTIONMercury is an ancient metal characterised by electrochemical nobility, volatility, low solubility in water and a liquid state at room temperature (Holleman and Wiberg, 2001). The biogeochemical cycle of mercury is complex. Elemental mercury may enter the atmosphere due its volatility, where it can be transported long distances. After settling and adsorption to sediments, methylation is catalysed through microbial metabolism (Qureshi et al., 2009). Methylated mercury species are potent neurotoxins, and bioaccumulation of mercury is well documented, particularly in seafood (Kozin et al., 2013, Pan et al., 2014, Pollman, 2014). Environmental regulations for mercury emissions are becoming increasingly stringent (UNEP, 2015). Considerable research has already been performed and technologies developed for the remediation of mercury in wastewater and the trapping of mercury from industrial stack emissions. Wastewater technologies usually target ionised mercury using adsorbent, ion exchange and complexation mechanisms (Krishnan and Anirudhan, 2002, Li et al., 2015a, Chiarle et al., 2000), while stack emission technology is dominated by impregnated activated carbon adsorbents (Gao et al., 2013, Zheng et al., 2012). Related developments include piezoelectric amalgamating sensors for in line detection of gaseous elemental mercury in industrial stack emissions (Kabir et al., 2015, Sabri et al., 2011). There is a paucity of research regarding removal of mercury from the Bayer process."

Jan 1, 2016

By Q. G. Reynolds, R. T. Jones

The choice of furnace design parameters has a marked effect on the integrity of the furnace that is constructed. The design methodology for DC arc furnaces typically begins with the chemical reactions and feed materials that define the process. The specific energy requirement of the process, and the feedrates of the raw materials largely determine the power requirement for the furnace. A chosen value for the 'power intensity' sets the diameter of the furnace. Justification is provided for why this is a good choice of scale-up parameter. Equations are presented to quantify the resulting trade-off between thermal efficiency and the degree of error that can be tolerated in the balance between power and feedrate. This improved understanding should provide a better rationale for selecting an appropriate power intensity (or furnace diameter) for future furnaces.

Jan 1, 2015

By M. Fiset, D. Belley

"To better understand the wear process of various materials that may be used as blades on snow removal equipment, the first step is to evaluate the influence of the load applied and the moving speed on road wear rates of one type of steel and three types of polymers. While the behavior of steel conforms to Archard's law, wear rates of polymers increase to a power of ex of the load applied according to a model implying that the wear of these materials is due to fatigue. The wear rate of some of the polymers varies considerably in terms of speed, unlike the steel. The wear resistance of some of these polymers outclasses the steel tested as long as the speed is not too great. They, therefore, present interesting alternatives for snow removal on more fragile surfaces such as sidewalks and zone made of inter-block slabs.IntroductionSince the dawn of the Industrial Revolution, the massive use of machines has brought with it a number of different problems regarding wear. Snowplowing roads, parking lots and sidewalks is an activity that generates enormous expense in a country such as Canada. To better understand these wear processes and in the hope of stimulating new approaches designed to reduce the costs related to this sector of activity, this paper presents the behaviour of several materials (steel, polymer and rubber) as they wear on an asphalt-fines matrix surface lubricated with water. Also discussed is the effect of various parameters such as the load applied and speed."

Jan 1, 1990

By T. Güyagüler, U. Y. Önder

"This study investigated the psychrometric properties of ventilating air in GAL coal mines. Related measurements were done in underground openings and have been arranged as input data for computer programs prepared for ventilation network and psychrometric analysis.Results obtained from network analysis have been used for psychrometric analysis of ventilating air. Changes in heat and moisture content of air in two major path s between entry and discharge of ventilating air have been investigated. Psychrometric processes occurring in the mine were determined and are shown graphically in Figures 1 and 2. Special attention has been given to determine the changes in psychrometric properties and processes involved in the faces. Results are outlined in this paper.IntroductionThe psychrometric properties of mine air are important factors to mine productivity and efficiency. Therefore, psychrometric analysis should be made for all underground mines; any undesired situation observe d could be corrected by taking the necessary precautions.The analyses were done as a case study for GAL mines, the only mechanized lignite coal mine in Turkey. In this mine, workable reserve is about 300 million tons of coal and yearly planned production is 2.2 million tons. Production is continuing from a coal measure-bed having two coal seams with average thicknesses of 1.52 m and 1.72 m respectively. A 0.85 m shale band exists between these two seams.Two full y-mechanized faces, approximately 220 m long, usually work simultaneously. All measurements, including mine gases and air velocity, are done by sensors connected to a control room by a monitoring system.In the analysis, a line diagram is utilized to described the mine on which every junction and branch is numbered."

Jan 1, 1992

By John Hughes

1. De Beers, Diamonds and Canada 1.1. De Beers was founded long ago (1888, the same time that Canada became a country) in a rural mining village in South Africa. Today, we employ 22,000 people across 19 countries and have 14 mines including open pits, shafts, beach-sands and seabed. 1.2. Last year our sales were US$5.7 billion and our total production amounted to 47 million carats which means a 40% global market share. For the Kyoto buffs in the audience, the company consumes 66 million cubic metres of water per annum, 210 million litres of hydrocarbon fuel and 1,600 GWh of electricity. Stats are good, but aren?t as expressive as a movie. This one is 2 minutes long, which is quicker than I could elaborate. (Video 1 - 2 minutes) 2. De Beers in Botswana is the leading source of diamonds 2.1 Today Botswana is the Jewell in the Crown. There are three big open pits that enjoy economies of scale that make them the lowest cost producers. Last year 60 million tonnes of overburden and 30 million tonnes of ore were moved in Botswana alone. Botswana produced 31 million carats, compared to 14 million carats in South Africa and 2 million very high quality carats inn Namibia. 3. Diamond Mines provide feedstock? ?.to jewellery stores

Apr 1, 2005

By H. Gharahbagheri, S. Shafiei Zadeh, H. Hassan Nejad, Reza Roostaazad

In this paper, dissolution of vanadium from mining residue, in which vanadium is associated intimately with magnetite ore, was investigated via both bacterial ( aerobic and anaerobic) and fungal activity. Although bacterial activity was tangible, it could not reduce and dissolve vanadium in both aerobic and anaerobic experiments. However, in fungal leaching, after 30 days about 36.9% and 29.7% of vanadium was dissolved for a pulp density of 10 and 30 g/l, respectively. At the end, the concentration of metabolites usually produced by fungal activity was optimized and oxalic acid was chosen as the main agent for the leaching process.

Jan 1, 2014

By J. Kochhar, Robert G. Cooper

"The Cape Breton Development Corporation is a federal Crown corporation which was formed in 1968. Initially, the Corporation had two divisions - the Industrial Development Division, whose purpose was to stimulate Cape Breton Island's economy, and the Coal Division with a mandate to phase out the operating coal mines. However, that strategy changed in the early 1970s with the Middle East oil crisis. As a result of that crisis, Nova Scotia Power Corporation adopted an ""off oil"" policy. Today, approximately 700/0 of Nova Scotia power needs are met by generation of electricity from coal. Therefore, since the early 1970s, emphasis has been on the rehabilitation of the Cape Breton coal mining business with the opening of three new mines.Today, Devco is solely a coal mining company which employs 3300 people.Physical DescriptionThe mines operate in the Sydney coal field which is located on the eastern tip of Cape Breton. The Corporation leases the deposit from the province of Nova Scotia and its leases cover all coal from the outcrop to the 4000 ft depth. The seams outcrop along the shoreline and dip beneath the ocean floor at dips varying between 5% and 100%.There are eleven seams, of which three - the Harbour, Phalen, and Hub - have been extensively mined."

Jan 1, 1990

By L. R. Bower

"This paper describes a highly versatile variable speed unit with a torque multiplication feature as a direct replacement for a fluid coupling .The unit is comprised of a modulating clutch with torque converter and lock-up options.The UCD does not start or stop the motor. This is carried out in the normal manner.The UCD continually monitors and rapidly regulates the output speed to the requirement of a set point demand from input signals or a pre-set program with full manual override.The pre-set program can include start and stop ramps, top speed and minimum speed regulation and also mid-speed set point with security for man-riding, etc. Speed variation is from zero to 100% on a constant duty basis.The input signals can be from any source, e.g. belt weigher. load profile bunker probes, mine monitoring system, etc.The UCD when fitted with a torque converter has a torque multiplication feature which automatically provides a starting torque up to two and a half times greater than the full load torque without exceeding the normal motor power levels.IntroductionIt is common practice in the mining industry to drive conveyors, whether they be belt or chain, through a transmission system incorporating a fluid coupling between the driving motor and gear-box .However, there are drawbacks and in an effort to attain a better degree of drive and control, two-speed motors - inverters cycle- converters - hydrostatic drives, etc ., have been introduced."

Jan 1, 1986

By K. R. Barnard, K. D. Marte, T. V. Gamarano

"The first commercial scale application of CSIRO’s direct solvent extraction (DSX) technology has been in operation at the Boleo project in Mexico since December, 2015. In this application, DSX is a synergistic solvent extraction system consisting of the extractants LIX 63 and Versatic 10 for recovery of cobalt and zinc from a solution background of manganese, magnesium, and calcium. Key operating parameters such as metal extraction, phase disengagement and extractant stability are summarized and discussed in this paper.INTRODUCTION Commissioning of the Boleo processing plant, located on Mexico’s Baja peninsula, began with the copper circuit starting in late 2014, with first copper cathode production achieved in January, 2015. The cobalt and zinc circuits began commissioning in December, 2015 with first zinc sulphate monohydrate (ZSM) and cobalt cathode production achieved in February and April, 2016 respectively. The Boleo project flow sheet and development has been described in detail in previous publications (Dreisinger, et al. 2005; Dreisinger, Baxter, & Molnar, 2006; Dreisinger, et al. 2008; Dreisinger, et al. 2009) and is summarized schematically in Figure 1. Boleo is a mixed oxide/sulphide Cu-Co-Zn-Mn high clay deposit that is processed in a whole ore, atmospheric, oxidative and reductive, sulphuric acid/seawater leach. Copper is recovered as cathode by conventional solvent extraction and electrowinning. Cobalt and zinc are recovered, from a solution background of manganese, magnesium, and calcium, by CSIRO’s synergistic solvent extraction technology Direct Solvent Extraction (DSX). Cobalt and zinc are bulk stripped from the DSX circuit and then further purified by phosphinic acid solvent extraction to produce zinc sulphate monohydrate granules via spray dried granulation and cobalt cathode rounds via divided cell electrowinning."

Jan 1, 2017