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By M. A. Stogran-Baker, S. Cole

"Fluorspar mining occurred in the St. Lawrence area from the 1930s until the mid 1980s. In 2013, CFI discovered a new ore body, the AGS vein, which proved amenable to more economic open pit mining methods. A new mill was designed to produce 200,000 tonnes per year of high quality, acid-grade fluorspar concentrate. The simple mill flowsheet includes crushing, dense medium separation (DMS), grinding, sulphide flotation, pulp thickening, fluorite flotation, thickening, and concentrate filtration. The type of flotation cell used is being installed for the first time in North America. Site clearing commenced in the spring of 2016, followed by mill building erection completed by the fall of the same year. Civil and mechanical installation as well as site-wide construction was completed by the end of September 2017. Commissioning commenced, and at the time of paper submission mill production is on track to ramp up to full capacity by the beginning of 2018. This paper will focus on the use of fluorine NMR analysis applied to fluorite and the development of on-stream analysis, flotation cell selection and the decision to install the new cells, and the water control program designed to maintain process control with the least possible environmental impact.HISTORY St. Lawrence is located on the south-eastern coast of the Burin Peninsula in Newfoundland and Labrador. The first occurrence of fluorspar in the St. Lawrence area was recorded in 1843 by British geologist J.B. Jukes (DNR 2010). Fluorspar was likely extracted in small quantities prior, however commercial fluorspar mining did not commence until 1933 at the Black Duck Mine. The Black Duck Mine operation processed ore by washing and screening – acid-grade was hand-picked from the oversize, the undersize was sold as a lower grade product. The Black Duck Mine was closed in 1941 (Wilson 2010). The American Fluorspar Limited (New Fluor) commenced operations on the Director vein in 1936, and was bought by Alcan in 1942 (Cooper 2012). Alcan also developed the Iron Springs as well as the Tarefare deposits. The Black Duck Mine mill had closed, and a new mill was built. This new mill crushed the ore prior to dense medium separation, the sinks of which were sent to Quebec for use in Alcan’s aluminum smelter (CFI 2016). Alcan shut down it’s mining operations in 1977 due to the dropping price of fluorspar as well as labour disputes. In 1986, the British-based Minworth Limited began producing ore from underground at Blue Beach North and Blue Beach South, as well as from open pits at Tarefare and Director veins (Cooper 2012). A new mill was built by Minworth in order to process the ore using flotation to produce an acid-grade concentrate. The low price of fluorspar caused Minworth to shut down operations in 1990. Whilst exploration has been ongoing, no mining had occurred in the area since 1990."

Jan 1, 2018

By W. McCombe, G. Remple, L. Zunti, M. Bernardin, L. Nightingale-Mercer

"The McClean Lake Mill is located approximately 700 kilometres north of Saskatoon, Saskatchewan, Canada and is operated by AREVA Resources Canada Inc. (AREVA). The mill was designed to process high grade uranium ores, and has been undergoing a multiyear expansion to increase its production capacity to 24 Mlbs U3O8 per annum, while also undergoing upgrades to allow it to safely transition to processing high grade ores from the Cigar Lake Mine. During the metallurgical test work on the Cigar Lake ores, it was identified that some ore zones in the Cigar Lake deposit have a propensity to generate hydrogen gas during acid leaching. Hydrogen is a volatile and explosive gas, which poses obvious safety concerns in the leaching circuit. Uranium processing is further complicated by the fact that an oxidant in the form of oxygen gas or hydrogen peroxide is required to regenerate iron in the leach, which further increases the risk from hydrogen gas. During 2013 Hatch and AREVA designed and engineered a number of novel upgrades for the leaching circuit to mitigate the risk of hydrogen gas evolution in the process. Best in class technology was utilized in addition to control and operating strategy changes to ensure the leaching circuit can be safely operated with ores that can evolve hydrogen gas. This paper reviews the design concepts and modifications implemented on this unique and challenging project.INTRODUCTION The McClean Lake mill was originally designed to process high grade uranium ores, however until 2014 the average ore grade processed was 1%. The facility has been undergoing a multiyear upgrade and expansion to increase its production capacity from 12 to 24 Mlbs U3O8 per annum, while also undergoing upgrades to allow it to safely transition to new high grade ores, averaging 18% U, from the Cigar Lake Mine. During the last round of metallurgical test work on the Cigar Lake ores, it was identified that some ore zones in the Cigar Lake deposit had a higher propensity to generate hydrogen gas during acid leaching than previous test work had indicated. Hydrogen gas is a volatile and explosive gas, which poses obvious safety concerns in the leaching circuit."

Jan 1, 2017

By Alex Rown

"THE SYDNEY COAL FIELD has long been afflicted by high costs and low productivities. However, a distinct possibility now exists that improvements can be made in costs, productivities and revenues. If these hopes materialize, the Sydney coal field will once again be regarded as a valuable asset in our national inventory of energy and metallurgical coals. The economic possibilities for the Sydney collieries depend on performance at the pits and in the market place. Because this audience is already well informed about colliery planning, I would like to start with an assessment of the modern coal market insofar as it may relate to the Sydney field. Since 1950 we have seen a vast growth in the population and industrial empires of the western world which has resulted in an enormous and escalating demand for energy. If the energy supply pattern of the first 50 years of this century had been followed, this would have led to an immense demand for coal."

Jan 1, 1972

By John B. Phillips

The mine is entered by a central vertical shaft, strongly timbered, and containing two compartments-one for the passenger cage, the other for the large skips bringing the ore to the surface. A man-way, for emergencies, is also provided, parallel to the shaft. The cage is a single-deck steel box, carrying about thirty persons; by means of arrangements above and below, it can also hoist and lower materials needed in the workings. Levels are run at intervals of 100 feet. In special cases, where the ore conditions warrant, sub-levels are operated, such as those at 1,113 feet and 1,123 feet (Fig. 7), which are connected by winzes with the 11 th level. One of these was pushed for 40 feet, and then abandoned because it was unprofitable to take up ore of the grade encountered. The ore between levels is removed by stoping. The drifts follow the course of the veins as much as possible, with numerous cross-cuts. Winzes, raises, connections, etc., are blasted out where needed. The main drifts are at least 8 ft. high by about 9 ft. wide. All former narrow drifts had to be widened sorne time ago, by ruling of the Ontario Department of Mines, to lessen the danger of accidents with cars in the small passages. Accurate plans of the under-ground workings are kept in the office, and extensive surveying is always being done underground to keep the maps up to date, measure the cubical contents of stopes, and so forth. Timber is extensively used in the construction of supports and chutes, and in the sinking of the shaft. Steel and concrete are too expensive to compete with timber, which 1s abundant in such sections as have escaped forest tires.

Jan 1, 1926

By John Ratti

Building on Canadian Capabilities for Space Resource Missions: Space resource science and technology mission building blocks Canadian historical perspective Status and future pursuits It takes Canadian Teamwork to succeed in space exploration! Space resource science and technology building blocks: Orbiting / Delivery Elements Spacecraft Sensors Landed elements Roving / Mobility, Autonomy Sample acquisition and handling Sensors, GN&C Science Operations Partnerships: Government ? Industry Between Industry With Academia and Scientists

May 1, 2013

By J. J. Crowder, A. L. Coulson

Ground support is a significant component of underground mining costs. The rehabilitation of failed support, however, is often much more expensive than the initial installation. This paper investigates whether the right type and length of support can be designed correctly the first time, through forward modelling of the support and the mining process. Back analyses demonstrate how high-quality instrumentation and monitoring can help with the estimation of the post-peak (post-failure) rock mass parameters required for a comprehensive analysis. A hybrid modelling approach combines a three-dimensional mine-wide boundary element model with a non-linear finite element model to allow for the failure process in the rock mass. The back analyses demonstrate that, for the case study site, the post-peak Generalized Hoek-Brown value of mr must be reduced significantly in order to properly simulate displacements observed in instrumentation data. High-quality instrumentation data is the key to post-peak rock mass parameter calibration. The procedures outlined in the paper highlight the need for a new hybrid numerical modelling package that can use the influence of three-dimensional mining-induced stresses to predict displacements in, and potential failure of, rock masses surrounding mining infrastructure in order to radically alter strategic and tactical mine design.

Jan 1, 2007

By P. V. Golde, R. A. Poole, G. R. Baiden

"INCO is committed to proceed into the next century using automation and robotics to achieve safety and productivity goals necessary to enhance its competitive position. Stobie Mine, decades old, is the first of its mines to change from labour-intensive to automationassisted techniques. This paper is a synopsis of the progress made during the transition period including overviews of some of the projects as well as some of the difficulties in the assimilation of the technology. BackgroundThe ObjectiveThis paper is an update on remote control and LHD automation installation at Stobie mine. The communications system installed at the mine and the ability to remotely control underground equipment from surface is reviewed (Poole et al., 1996, 1997). It discusses some of the experiences and processes required to further the concept to consolidate the operation of multiple machines under a single operator. It considers the communications systems requirements and their focuses, particularly on the development of systems for the tele-operation of LHDs and drilling machines from surface."

Jan 1, 1998

By Lawrence Bragg

WE associate metals with hardness, toughness, and strength. But a curious paradox lies at the root of the valuable mechanical proper-ties of the metallic state: in order to be strong, a metal must be weak. This paradox, and the equally surprising fact that, in a sense, metals are not true solids at all, are among the topics here discussed by Sir Lawrence Bragg. (1) WHAT METALS MEAN TO US We employ various materials to build or fabricate the many objects we use in everyday life, choosing those whose properties are most suitable for the purpose which the object has to serve. Certain of these materials have been used from the earliest times, such as stone, wood, leather, and animal or vegetable fibres, each with its own peculiar valuable properties. Stone resists crushing and is very durable and permanent, as indeed it must be, since it has so long resisted change as a part of-the earth's crust. It is there-fore ideal for walls and buildings, and very early in his history man discovered how to make artificial stones by burning clay, with the advantage that they could be given any desired shape, and made into bricks or given elaborate forms as pottery. Wood is strong and tough and light, it resists tension as well as compression, and is nor brittle like stone. It forms beams and furniture and parts of tools or weapons. Leather is tough but at the same time iris flexible; it is ideal as straps or sheers. Vegetable fibres such as linen or cotton, and animal fibres such as wool and silk, owe their value to their flexibility and strength in resisting extension. They can be spun into yarn or rope, and woven into cloth. The technological age in which we are now living is replacing the natural products used by early man by a series of artificial products, but it is remarkable to see how in nearly every case we are copying Nature's materials. The wide use of concrete represents a developed art of making artificial stone. Artificial fibres such as rayon or ?nylon replace cotton, wool, and flax. Plastics are coming very much to the fore; they correspond to early man's use of horn, another substance with peculiar properties of roughness in all directions without the 'grain' of wood. For the most part we are following in the footsteps of our remote ancestors, though we can make for ourselves what they had to cull from wood and field. There are exceptions; for instance, we have discovered comparatively recently the number of uses to which natural rubber can be put, and are now making it artificially. This is a really new discovery; our ancestors had nothing with such remarkable powers of elastic stretching without breaking, and resistance to being abraded.

Jan 1, 1943

By J. Janzen

The cost to supply ventilation may exceed 40% of the total mine energy cost for underground mines and is often higher for deeper mines. The goal of Ventilation-on-Demand (VOD) is to ensure that the required quantity and quality of air is supplied to underground mining crews and diesel equipment at the least energy expenditure (minimum cost). A VOD system may include control of surface fans (Supply & Exhaust), underground booster fans, auxiliary fans and automated regulators/dampers to regulate the flow of air with more control elements providing more value. Strategically located Air monitoring stations measure air quantity and quality and provide feed-back enabling control. The modular design involving controls, intelligent instrument and intelligent motor control centres coupled with a communication network allows the quick installation, commissioning and expansion of the system as the mine develops. The result is a very robust, flexible system while reducing maintenance costs and spare parts. This paper discusses the impact of sensors, installation and commissioning on advanced controls and provides solutions for in-field applications.

Aug 1, 2013

By J. D. Robertson

An in situ water sampling device has been developed to measure biologically-available or “labile” metals in natural waters and effluents. The active mechanism involves the use of a polyacrylamide gel layer to quantitatively control metal transfer to a trace-metal-adsorbing, gel-imbedded resin. Because the resin only adsorbs free metal ions (the gel sampler methodology is a kinetic speciation technique), and because metal bioavailability is related to the free-ion activity, the device provides a direct measure of the biological-availability of metals in the environment sampled. The prototype consists of a layer of ion-permeable polyacrylamide gel which separates the solution to be sampled from an ion exchange resin. Because approximately 90% of the polyacrylamide gel is water, mass transport through the gel is diffusion-controlled, and is therefore well defined. Metal ions are rapidly bound by the resin, creating a steep concentration gradient in the gel. The amount of labile trace metal that accumulates on the resin can be related directly to the concentration of the metal in solution, the exposure time and the molecular diffusion coefficient of the labile species. In addition, the passive nature of this device affords it the potential to address many of the limitations presented by conventional sampling methods, such as sample contamination introduced during collection or filtration and changes in trace metal speciation prior to analysis. Laboratory studies and limited field trials indicate that the sampler behaves as anticipated and illustrate that biologically- available metal concentrations in many environments are a small fraction of the total concentrations and often significantly less than the dissolved concentration. The implications of this on regulatory criteria are discussed. Additional field trials and correlation with bioassays are currently underway.

Jan 1, 2000

By John Shirokoff, Ladan Khaksar

"Cyclic polarization technique and also potentiodynamic measurements were applied to study corrosion behavior of 13% chromium steels in chloride containing environment. Potentiodynamic measurements were performed at 25 and 75 °C with 0, 10 and 20 g/l NaCl in 0.01 M hydrochloric acid solution. At the same time, the significant pitting parameters such as corrosion potential (Ecorr), pitting potential (Epit), protection potential (Epro) and passive current (Ipass) of cyclic polarization curves with various NaCl concentration were analyzed and compared to describe the corrosion behavior of 13% chromium stainless steel. Surface measurement techniques such as SEM and EDS were used for morphology and analysis of corrosion products. The results showed that both temperature and Cl- concentration had significant effects on corrosion behavior of 13% chromium stainless steel in acidic solution.INTRODUCTION Of all the corrosion resistant alloys (CRA) used in oil and gas developments, martensitic stainless steels (MSS) are some of the most common ones these days. These steels not only have the advantages of normal steels: high strength, cost-effective, easy to manufacture, available in a wide variety of product forms, but they also have good CO2 corrosion resistance at higher temperatures as a result of their 11% minimum chromium content. One of the most common types of MSS used in the oil and gas industry is 13% chromium steel. NACE and API standards both reference several different varieties of 13% chromium steels for use in oil and gas projects(“Corrosion Resistant High Cr Steel for Oil and Gas Wells,” 2013). All types of 13% chromium steels have about 12 to 14% chromium and other minor alloying additions, and can be placed into two general groups: conventional and modified. Conventional 13% Cr steels (13Cr) are those most common in oil and gas, some of which are CA6NM (UNS J91150), AISI 410(UNS S41000), and AISI 420 (UNS S42000). These alloys have excellent corrosion resistance when compared to carbon steels up to about 300°F (150°C) and are used for a variety of wellhead, tubular, and downhole components however they have very limited resistance to cracking in H2S (Vallourec Group, 2015). Modified 13% Cr (M13Cr) steels came from the need for increased corrosion resistance at higher temperatures, increased H2S cracking resistance, and increased yield strength above 85 ksi (586 Mpa) primarily for tubular goods and other downhole equipment. These features were developed by taking a conventional 13Cr steel and adding nickel (Ni), molybdenum (Mo), copper (Cu), and other alloying elements. M13Cr provides better corrosion resistance than 13Cr up to about 350°F (177°C), yield strengths up to 110 ksi (758 Mpa), and also improved H2S cracking resistance(“Corrosion Resistant High Cr Steel for Oil and Gas Wells,” 2013)."

Jan 1, 2017

By A. J. Oliver, C. E. O’Neil, I. J. Itzkovitch, V. A. Ettel

A new solvent extraction process for the separation of cobalt, copper and zinc from nickel sulphate process streams has been developed. It involves selective extraction of these elements with a quaternary ammonium thiocyanate dissolved in an aromatic diluent. The chemical principles of this process have been investigated and are described, together with background physico-chemical data relating to the use of this solvent. Long-term testing in a continuous "mini-plant" circuit gave high-purity nickel and cobalt products (Ni/Co —200011 and Co/Ni ~1000/1 respectively).

Jan 1, 1976

Iron control and iron residue management and disposal are significant issues in all zinc production processes. This paper briefly reviews the most important primary zinc production routes and discusses the challenges posed by iron control in each of them. The technologies and strategies that have proven successful in controlling and managing iron are discussed. SNC-Lavalin's experience in designing and commissioning zinc plants provides a unique perspective from which to review this aspect of zinc production.

Jan 1, 2006

By Staff

The Tetreault mine, operated by the British Metal Corporation (Canada), Limited, holds a unique position in Canadian mining, being the only steady producer of zinc in Canada east of the Rocky mountains. Its importance in Canadian zinc production may be gauged with some accuracy, since, in 1927, it was responsible for over 13 per cent of the zinc output of the Dominion. In addition, it also made valuable contributions to the production of lead, silver, and gold. Location: Situated in the foothills of the Laurentian mountains, 600 feet above sea level, 20 miles from the St. Lawrence river, and 52 miles due west from the city of Quebec, the property is in the township of Montauban, county Portneuf, Province of Quebec, as shown in Figure I. The municipality of Montauban, immediately adjoining the mine, has a permanent population of 700 people and is six miles by road from Notre Dame station on the main line of the C.N. Rys. between Montreal and Chicoutimi-Notre Dame being n6 miles by rail from Montreal. Connection by 19 miles of dirt-and-gravel road with the Provincial highways' system of Quebec Province, the city of Quebec, which is distant 78 miles, can be reached by automobile in less than three hours, while the distance to Montreal by road is 16o miles .

Jan 1, 1928

By M. H. MacLeod

"IntroductionTHE ORE PASS raise system at the H.B. mine as contracted by the Patrick Harrison Company consisted of two raises 6 ft. by 10 ft. in section •at 60 degrees to the horizontal. No. 88-88 raise, the longer of the two, was a straight raise 690 feet long, with access only from the bottom. In addition, this raise had two branch knuckle-backs only one of which was driven by. the Patrick Harrison Company. The other, known as 88-89 raise, was 540 feet long with knuckle-backs at 280 feet and 410 feet. Its access, also, was from the bottom (see Figure 1)."

Jan 1, 1954

By L. E. Puddington, A. L. Mular

"Since the inception of spherical agglomeration, few investigations to exploit commercially the technique in the metallurgical field have been conducted. Of these, none appear to have been carried sufficiently far to demonstrate commercial feasibility.This paper describes a continuous agglomeration-separation process that can rapidly handle large tonnages of ore material. A small pilot plant de-signed from information obtained with the semi-batch unit described herein is currently in operation.In the absence of a reagent recovery system or cheap reagents, the process is probably not economically attractive for many common ores. However, for iron ores, the fuel content of the agglomerates can be used in a subsequent step such as direct reduction."

Jan 1, 1968

By W. Gordon Muir

This paper deals with the exploration, development and current operations of the salt mine at Goderich, Ontario operated by the Sifto Salt Division of Domtar Chemical Limited. The rock salt is obtained from a bed 1,760 feet below the surface, 75 feet thick, extending under Lake Huron. Annual production is in excess of one million tons. Large mobile equipment is used. Details of this equipment, as well as the shaft layout, which permits the equipment to be lowered underground with a minimum of trouble are outlined. Mining, crushing and screening procedures' are rev1ewed. Reference is also made to productivity salt distribution and uses.

Jan 1, 1967

By W. G. Scott

IT IS APPROPRIATE that your Institute should have chosen, for its 1956 Annual General Meeting, the Capital City of a province which is making such rapid advances in mining. The railway industry is proud to be playing an active role in this development, expenditures on equipment and railway construction in the Province of Quebec alone in recent years being in ?excess of a quarter of a billion dollars. In looking up some background material for this address I ran across a definition of a mine by Mark Twain, the great American humorist, which I thought might amuse you. He said that a mine was "a hole in the ground owned by a liar". I am sure that if he were alive to witness the enormous value attached to Canada's mineral resources today he would quickly change his definition. Canada's postwar record of mining development has been staggering in its variety and enormity. Historically, only the ?construction of our transcontinental rail ways outranks the largest of three of these development projects - the aluminum undertaking at Kitimat; the Quebec-Labrador iron ore deposits ; and the petroleum and natural gas developments in Wes tern Canada.

Jan 1, 1956

By G. O. Prickett, P. Somasundaran

An application of the statistical and computer techniques in basic mineral processing research is illustrated by means of a case history involving the study of starch adsorption on calcite. Multi-factorial experimental designs and computer techniques were used for determining the effect of different system variables, such as solution pH, sodium oleate concentration and starch concentration, and to obtain a mathematical model of the response. Response maps enabled the investigators to see the effects clearly and to predict the results of changes in factor levels within the design region. Use of time-shared computers and plotters made data processing and analysis efficient and relatively inexpensive.

Jan 1, 1973

By Knud Sinding

Many industries have established their own systems for self-regulation. They often do so when companies operate in countries where financial, technical, environmental and social regulation is weak and when the industry is challenged by legitimacy issues related to behaviour in one of these areas. Mining is one industry that has progressed unevenly down the road of self-regulation in these areas. This paper examines how the development of self-regulation for mines and mining companies involves difficult questions of scope, rules, membership, assessment criteria and performance evaluation. Using a range of theoretical and empirical results from research on self-regulation, performance rating and corporate strategy, this paper analyses the strategic and operational issues related to the idea of self-regulation in the mining industry. The analysis indicates that while self-regulation may bring benefits to members, they are likely to take a long time coming; but when they do arrive they may be substantial. Using the fact that in relation to technical and financial issues the industry is quite experienced in self-regulation ? not least as it is more reluctant in areas such as environmental and social performance ? the case is made for a comprehensive and innovative approach, that draws on the areas where the industry is experienced and develops new institutional solutions in the areas where the industry is more reluctant.

Aug 1, 2013