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By J. F. Perreault, J. Paraszczak

"The profitability of an underground mine depends to a great extent on the production cost.Random equipment failures and their consequences have significant influence on the total operating cost of a mining system. Having this in mind, a reliability study has been initiated for loadhaul- dump machines in an underground mine. The main purpose of this study is to identify the critical machine subsystems, determine their failure pattern and help work out an effective maintenance strategy. In the first part of this study, the failure data of diesel powered LHDs, gathered during an I8-month period have been analyzed. For the purpose of the analysis, the machines have been treated as systems comprising seven subsystems connected in series. The most critical subsystems, i.e. electrical and hydraulic, were further investigated, and analyzed by graphical and analytical methods. Different failure distribution models were applied and discussed. Basic Defmitions and ConceptsIn order to avoid confusion, several terms used in this paper are defined below, as compiled by O'Connor (1991). The acronymsBS and MIL-STD stand respectively for: British Standard and US Military Standard.Failure: the termination of the ability of an item to perform a required function (after BS 4778).Time Between Failures (TBF): the length of time between two consecutive failures.Observed Mean Time Between Failures (MTBF): For a stated period in the life of an item, the mean value of the length of time between consecutive failures computed as a ratio of the cumulative observed time to the number of failures under stated conditions (after BS 4778).Maintenance, Corrective: The actions performed, as a result of failure, to restore an item to a specified condition (after MIL-STD-721 B).Maintenance, Preventive: The actions performed in attempt to retain an item in a specified condition by providing systematic inspection, detection and prevention of incipient failure (after MIL-STD-721B)."

Jan 1, 1994

By M. Rantapaa

Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput. Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore. Barrick Goldstrike?s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs.

Jan 1, 2005

By J. W. Merkley, K. B. Hustwick

"The authors describe the use of a computer system for the control oj warehouse inventory at Cominco's Canadian operations. The challenge presented by the company's diverse products and various locations necessitated a practical approach to operational and manpower requirements. The utilization of modern forecasting techniques, manual intervention and exception reporting provides system flexibility. The system also provides both operational and management control to set required service goals at the lowest inventory levels for inventory management.IntroductionCominco Ltd. is a Canadian company, with international operations, the principal business of which is zinc, lead and chemical fertilizer s. Its involvement is fully integrated and range s from mineral exploration through mining, smelting, refining and by-product production to international marketing. It also embraces related services, including trade, wharfarge and power. With head office in Vancouver, it is involved, directly or through subsidiary or associated companies, in Canada and in the United States, Greenland, Europe, Australia, India and Japan.Cominco has over 12,000 employees and 26,000 shareholders, with 91% of all shares held in Canada.Cominco's Inventory Control System is one of the most extensively used computer systems employed by the company. Also, inventory control is regarded as one of the most economically successful computer applications to be undertaken by the Data Processing Services (D.P.S) Group that was responsible for the development of the Inventory Control System.The main use of automatic inventory control has been at operating plants in Western Canada and the Northwest Territories, which are separated by large distances. Each location has equipment-intensive mining and processing operations and it is essential to maintain control of parts and supplies inventories. Some of these locations are remote from urban and industrial centres and it is important to avoid the adverse effects of high personnel costs and re-training due to turnover."

Jan 1, 1982

By R. Mckinstry, M. Rantapaa, T. Bolles

"Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the open pit and process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput.Better fragmentation and a subsequent increase in mill throughput were achieved through the use of electronic caps for more precision and flexibility, as well as for allowing extremely fast shots; explosives with a higher velocity of detonation (VOD) to provide for improved shock energy; and improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by 6 tph in 2003 due to the improved fragmentation of the hard ore.Barrick Goldstrike’s D2M initiative includes roaster hard ore (BWI>17), as well as autoclave hard ore (BWI>15). Approximately 6 million tons of D2M material were shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs."

Jan 1, 2005

By Erwin L. Zodrow

"This paper is based on a statistical analysis of the Smallwood iron ore mine (6). In this mine, the prediction of magnetite is especially difficult because of strong trends. Recognizing the statistical limitations of the sample data, the paper approaches the basic statistical analysis of the magnetite by endeavouring to obtain a first approximation of its sample density function. The knowledge of the distribution of a random variable is essential for several reasons, but particularly: (1) to obtain reliable estimators of the population parameters -for example, mean and variance; and (2) to use these estimators in hypothesis-testing concerning future experiments -sample points and sample intervals."

Jan 1, 1968

By C. I. Walker

Field tests at a number of large mineral processing operations have been undertaken to better understand the wear life impact of different aspects of pump design, materials of construction and maintenance procedures. Data are presented for wear rates, and typical result variability is explored. To improve the availability of pumping equipment in a milling circuit it is not only important to improve the wear life, but also reduce the variability in the wear life of components so that the incidence of premature failure is lessened. Localised gouging wear due to flow separation and turbulent eddy formation is often the point at which part-holing occurs. A number of improvements to the design of pump impeller and throatbush (suction side liners) to reduce the localised gouging wear are outlined. Also, results are presented on the use of composite materials (mix of metal, rubber and ceramic) for throatbush materials to protect specific areas against wear.

Jan 1, 2012

By K. S. Raja, B. McNall, B. Pesic

"High-level radioactive wastes are stored in large underground storage tanks made of low-carbon steel. The wastes consist of concentrated solutions of sodium nitrate (NaNO3) and sodium hydroxide (NaOH), and the radionuclides 137Cs, 99Tc, and 90Sr. The corroding steel microenvironment may produce localized reducing or oxidizing conditions that affect the solubilities of the species such as Tc(VII) and Tc(IV), which in turn modifies the kinetics of corrosion of the storage tank. To understand the influence of technetate ions on the corrosion of steel, electrochemical polarization studies of A 537 steel samples were carried out in 1 M NaNO3 + 0 .05 M S r(NO3)2 + 0.1 M NaOH with and without addition of HReO4 at different temperatures (24 – 85 °C). The concentration of HReO4 was varied from 0.014 – 0.04 M.INTRODUCTIONAqueous processing of spent nuclear materials generates a large amount of high-level radioactive wastes. The wastes are primarily salt solutions of sodium hydroxide and sodium nitrate which also contain fission products such as 137Cs, 99Tc, and 90Sr. Among the high level radioactive fission products, Tc-99 is of great importance because of its high concentration, long half-life (2.1 x 105 years), high solubility in geologic waters as technetate, and rapid diffusivity through the geologic systems. The solubility of technetate ions varies depending on the oxidizing conditions prevailing in the storage containers. High level radioactive wastes are stored in single shell or double shell tanks made of low carbon steels such as ASTM type A15, A516-70 and A537. Most of the available literature on corrosion of steel in simulated radio active waste environments pertains to nitrate induced stress corrosion cracking (Subramanian & Mickalonis, 2005). The corroding steel microenvironment may produce localized reducing or oxidizing conditions that affect the solubilities of the species such as Tc(VII) and Tc(IV). Corrosion of steel and formation of Fe(II) and Fe(III) will affect adsorption and reduction of Tc species. The radioactive species can irreversibly be sorbed on the steel surface by oxidation of Fe(II) to more stable Fe(III) and fixed as less soluble Tc(IV)/Fe(III). The solubility of Tc species is also affected by other factors such as dissolved oxygen, local pH, temperature etc. How the corrosion behavior of steel will be affected in the presence of Tc species is not clearly understood.Cartledge (Cartledge, 1960) demonstrated that passivation of iron can be achieved in the presence of oxygen along with suitable inhibitor ions/molecules of the general formula XO4 n-, such as pertechnetate (TcO4 -). The pertechnetate ion is univalent. Since it is derived from a strong acid, no buffering action can be expected from this ion. The redox potential of the reaction (1) is 0.738 VSHE (Pourbaix, 1974)."

Jan 1, 2012

By Dennis Z. F. Mraz

"Because rock salt and pot ash formations contain particles capable of elastic deformation, the material has usually been compared with various rheological models containing elastic elements. Extensive laboratory testing of salt and potash samples resulted in various theoretical conclusions based on conditions quite different from those in a deep mine. It is felt that sufficient data have now been collected from underground measurements and observations to demonstrate the inelastic behaviour of salt masses in a deep mine. The conditions in deep salt strata can be defined as near hydrostatic, because the acting pressures are very high compared to the negligible elastic limit of the salt. The pressure field and creep around the single opening is a function of its shape, size and age. The same factors, together with extraction, determine the behaviour of the mining a rea. The application of the correct analytical method in mine design can significantly improve the excavation techniques and predetermine the long-term behaviour of openings."

Jan 1, 1973

By George F. Crocker

Introduction The Helen mine and the Victoria mine of Algoma Ore Properties, Limited, in the Michipicoten district, Ontario, are 120 miles north of Sault Ste. Marie, on the north shore of lake Superior. They are on the Algoma Central railway between Hawk Junction and Michipicoten Harbour. Between them, these mines have produced 10,757,113 tons of iron ore. From 1900 to 1918, 2,823,369 gross tons of brown ore was shipped, and from 1939 to the end of 1949, 7,933,744 tons of siderite was produced from the open-pit operations and underground development. The finished product, known as 'Algoma sinter', is shipped to blast furnaces both in Canada and the United States. The iron-ore bodies are a part of a tabular shaped area of iron formation that extends over a length of more than 10,000 feet and has maximum width of 1,000 feet. The two siderite orebodies, known as the Helen and Victoria, are separated by two diabase dykes. The Helen orebody is 1,600 feet long with a maximum width of 250 feet and the Victoria is 1,200 feet long with a width comparable to the Helen. These orebodies are considered to be a replacement of the original rock by iron carbonate. The introduction of the iron-1bearing material probably occurred after the development of the major folded structures. The open-pit mining of siderite started in the Helen ore body in 1939 and continued until 1945. During this period, 3,853,395 tons of ore was mined. Open-pit mining started in the Victoria body in 1946 and is still being carried on. Underground development commenced in September, 1947. Diamond drilling and surface sampling had shown the Helen deposit to average 35.61 per cent Fe and 7.28 per cent SiO2, and the Vi.otoria deposit 33.73 per cent Fe and 10347 per cent SiO2?

Jan 1, 1950

By A. A. Beland, R. J. Dawson, S. Shewchuk

"Shovel buckets, scraper blades, dipper teeth, mine car wheels and hammermills are examples of equipment which require routine maintenance due to abrasion. Service life can be extended by the use 0/hard/acing and buildup materials. Mining and milling applications are described and field welding procedures discussed.A high-stress abrasion test used to select hard/acing and buildup materials/or hammers in a hammermill is described in detail. Field tests of the selected alloys confirmed their performance, and maintenance records showed a significant saving in down time and cost.The relationship between the abrasion resistance of the alloys and their hardness, work hardening, composition and microstructure is summarized. IntroductionLarge volumes of ore are handled daily by the mining industry. The abrasive nature of most ores results in extensive wear to both handling and processing equipment. If such wear is neglected it may cause lost production time and also, in extreme cases, require the complete replacement of expensive equipment. The well-planned maintenance of components subject to abrasive wear by means of buildup materials and hard facing can result in substantial economic benefits. Such benefits can , however, only be realized through the correct choice of welding process, consumables and deposition methods available to maintenance personnel. Hardfacing MethodsHardfacing is applied by a variety of methods; the three most widely used being arc welding, oxyfuel gas and thermal spraying. Table 1 summarizes the major processes used within each method. Filler metals in the form of rod, wire or powder are necessary to fulfill the individual requirements of each process. The filler rods are available in the cast form or, in the case of ductile metals or alloys, as wrought rod or tube. All types are supplied bare or flux covered. Wire is supplied in two forms, drawn flux cored and drawn solid. Powder filler metals are available in many metals or alloys; they may be simple mechanical mixtures or prefused and atomized alloys made to a specific size range and shape for optimum results for each applicable process."

Jan 1, 1980

By M. W. Lewis, B. Sambirsky, J. Werner

A mine’s inherent capacity is dictated by factors such as equipment, design, people, processes, and environment. Actual production may approach, but never surpass, the inherent capacity limit. The inherent capacity ceiling can only be increased through re-engineering. Autonomous haulage systems have the potential to significantly increase a mine’s inherent and realized capacity. Realized capacity may be maximized through the optimization of soft factors such as the processes, behaviours, and organizational systems, controlling asset utilization, availability, and performance. Truck shovel dispatching systems revolutionized the utilization of mobile assets. High-precision global positioning systems (HP-GPS) are increasingly being adopted to optimize equipment performance. Real-time maintenance management systems have the potential to revolutionize equipment availability and significantly reduce cash costs. This paper explores some of the solutions available to mines to increase their inherent capacity and maximize their realized capacity.

Jan 1, 2004

By A. Taylor, M. Blanchette, J. Doucet

"A Z1600 Jameson Cell Test Rig was rented for test work at Vale’s Clarabelle Mill operation. This paper discusses the evolution of renting the unit for test purposes to owning the unit and operating it as a revenue generating process component. The paper focuses on three aspects of the Z1600 project; the initial rental and installation, the test work performed in the cleaning circuit, and the business factors which led to the unit being permanently incorporated into the copper circuit.INTRODUCTION Clarabelle Mill is located in Sudbury Ontario (approximately 350 km north of Toronto) on the southwest rim of the Sudbury basin a meteoric impact crater that is 62 km long and 30 km wide. The result of the meteoric impact was concentrated nickel (Ni), copper (Cu) and platinum group metal (PGM) ore bodies in the outer perimeter of the basin; described in more detail by Hanley (1957). Vale currently has seven operating mines in the Sudbury basin, from which nine distinct ore types are mined. Ores are also received from two QuadraFNX mines. Clarabelle Mill processes all of these ores for the Ontario Operations of Vale. The mill, commissioned in 1971, was originally built as one of four mills operated by then Inco Limited. Between the late 70’s and the early 90’s process changes were made to consolidate the Sudbury Operations milling processes into a single operating mill, Clarabelle Mill. In 1990, the SAG mill was installed resulting in peak mill throughput of 11.9 million short tons per annum (Mstpa), with typical throughputs of ~10 Mstpa. Mill average feed grades were 1.4% Cu and 1.2% Ni. During the resources boom, plans were developed to increase the mill capacity at Clarabelle Mill in stages to a final capacity of 13.5 Mstpa. The project known as the Clarabelle Mill Expansion and Recovery Project (CMERP) included expansion and reconfiguration of the grinding and flotation circuits. The first stage was a planned increase in grinding capacity with the reallocation of existing mills, the existing flotation capacity would be required to treat higher throughput until the new flotation circuit was constructed."

Jan 1, 2012

By F. Musuka, D. Jenkins, A. Keyes

BHP Olympic Dam operates a Direct-to-Blister copper flash smelting Furnace (DBF) and an Electric Slag Cleaning Furnace (ESCF). Tapping blister copper from these furnaces via tapholes is a routine task carried out by trained personnel. Blister tapping is a high-risk activity with personnel operating in close proximity to molten metal. BHP’s risk management framework has identified taphole integrity as key to managing the potential for loss of molten metal containment and molten metal – water steam explosion, both of which have the potential to cause multiple fatalities. As part of the focus on managing this risk, since 2017, a dedicated Taphole Development Team has been embedded in the operation to run an accelerated improvement program focused on safely and sustainably embedding an improved taphole design with greater integrity. The program of works includes selecting and testing of new materials as well as improving operating discipline by collaborating with tapping personnel to convert their knowledge into codified condition monitoring and operating strategies. Computational fluid dynamics (CFD) is being used to derive critical risk controls, and to develop live-alerts to infer excessive refractory insert wear. To date, improving DBF blister taphole mudgun clay has led to more consistent drilling depths and subsequently reduced oxygen lancing requirements, resulting in improvements in taphole insert service life. On the ESCF, insert performance testing and development of a new taphole condition monitoring strategy, is being used to increase taphole insert tonnages to more sustainable levels. Operations personnel have been closely involved in different phases of the change management, this has led to standardization of tapping practices for both furnaces, and improved ownership of the proposed changes. The paper discusses the maturity in taphole integrity risk management as a result of recent and ongoing developments. It then provides an overview of future taphole developments proposed at Olympic Dam. INTRODUCTION Tapping operations at Olympic Dam and learning from significant events The Direct-to-Blister furnace (DBF) at Olympic Dam was built with a conventional design blister taphole, which was designed for manual oxygen lancing and clay stopper bar plugging tapping operations (Campbell, 2005). Manual tapping is a high-risk activity, where personnel work in close proximity to molten metal, and molten metal personal protective clothing and equipment must be used. Opening tapholes by oxygen lancing is a skilled activity and unintentional damage to the taphole inserts can occur. Since 2008, a Mudgun and Drill unit has been developed and trialled and is now in use on the DBF blister tapholes, to remove personnel from the line of fire when opening and closing tapholes. This has the additional benefit of reducing lancing damage to taphole inserts. A new taphole design labelled the Modular Blister Taphole (MBTH) was developed at Olympic Dam for the Mudgun and Drill operation. The intent of the design was for mudgun clay to fill the entire tapping channel when plugging after a tap. The drill would then drill through this clay plug to open the taphole.

Jan 1, 2019

By Lee Nichols

Convergent Bitumen Recovery Context of discussion It should be noted that the CBR process is a conceptual bitumen recovery feed methodology, designed to provide supplemental bitumen to the oil sand operations of Northern Alberta. To date the following have beencompleted. ?Bench Scale testing. ?Peer group brainstorming. ?Energy Balance ?Confidentiality agreements have been signed with several companies Discussions are ongoing with industry and although conceptual atthis stage the process holds significant promise.

May 1, 2007

By S. Duvah Pentiah

The transformation of an open pit coal mine to a horizontal-punch underground mine is subject to a number of challenges. These include scheduling the operation of various sizes of trucks over a long period, as well as updating delivery routes and dump site locations as the mine transformation progresses. In this process, rock is excavated from a quarry through earthworks. The bulk earthwork and quarry material delivery were initially drawn from traditional planning and experienced issues in their early phases. As a result, a traffic simulator was developed in order to validate schedules and predict achievable throughput, likely delays or blockages in the long term. The dynamic traffic simulator was also used to provide traffic density and vehicle arrival data at selected intersections in order to identify possible safety and efficiency issues.

Aug 1, 2013

By H. Ewaschuk

"INTRODUCTIONRio Algom's involvement with the Enviro-Clear thickener began in May 1975, when tests on a laboratory waif were carried out by our Research and Development group. Commencing in June, further tests were carried out using a 3 foot diameter pilot unit. By December, a 30 foot full-scale thickener had been installed. In the near future, 3 more Enviro-Clear thickeners will be commissioned. With in the space of a year, almost $2.5 million had been committed to liquid/ solid separation facilities using the Enviro-Clear thickener. This paper briefly traces the extent and development of this commitment.BRIEF HISTORY OF QUIRKEQuirke Mine started operating in September 1956 at a rated capacity of 3,000 TOD. Because of market conditions, Quirke was shut down in December 1960. The facilities were re-opened at an increased capacity of 4,000 TPD in July 1968, by which time the demand for uranium had returned. Also, a second shaft was sunk, and by 1970, all of the ore treated in the concentrator was coming from the new Quirke II mine. The Quirke I stopes were allowed to fill with natural seepage. As well, acidic barren solution from the concentrator was pumped underground.With increasing demand for uranium, the capacity of Quirke will be further expanded to 7,000 TPD by 1978. Studies of how this expansion could best he carried out led to the consideration of a fairly new piece of equipment, the Enviro-Clear thickener, for certain operations in the concentrator. These operations are as follows:"

Jan 1, 1977

By Pierre Gratton, Gordon Peeling

The Mining Association of Canada launched the Towards Sustainable Mining initiative in 2004. TSM’s goal is to improve the mining industry’s performance by aligning its actions with the priorities and values of Canadians. The initiative currently includes performance indicators for four areas: tailings management, energy use and greenhouse gas management, external outreach and corporate crisis management planning. Over the past year, the association has been designing a performance assessment and verification system for these performance areas, as its members prepare to move to external verification of their performance in 2006. The presentation will describe the initiative and its evolution, as well as the challenges faced in developing a verification system applicable to an entire sector.

Jan 1, 2006

By G. Winkel

"Safety conditions in industry have greatly improved over time. However, around the world, in Canada, and in each province or territory, people are still the victims of serious industrial accidents. The increasing safety of people at work then continues to be an imperative in industry today. In addition to protecting people, safety has been shown to make good business sense in any industry.The road to safety improvement is built on establishing a culture of safety that forms the basis for how work gets done in a company. Most importantly, an effective safety culture is built on the full engagement and participation of workers and leaders alike, who share in a vision for safe work performance where “no one gets hurt” and “everyone is a leader in safety.”Let’s learn together on how we can make a safety culture happen. The resulting bias for safety will ultimately save lives, and fulfills our moral objective to strive for safety excellence. IntroductionWe have the good fortune of living in democratic countries where freedom and the value of human life are key beliefs. These beliefs translate into the moral obligations and laws that we value and uphold in our society and life today.A minesite or workplace is simply a necessary part of our society where people earn a living. It is a place where our moral obligations and laws equally apply, a place where human life is of ultimate importance and value. In the early years of industry, this value has not always been evident. Take this description of a tragic accident reported in a coal mine on December 8, 1879:“Oliver Thompson, shaftman, aged 35— While taking wooden partitions out of a ventilation shaft, he fell off the work platform a distance of 100 yards, there did not appear to be anything unusual to account for this accident.”"

Jan 1, 2004

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 M. W. Lewis

A mine's inherent capacity is dictated by factors such as equipment, design, people, processes, and environment. Actual production may approach, but never surpass, the inherent capacity limit. The inherent capacity ceiling can only be increased through re-engineering. Autonomous haulage systems have the potential to significantly increase a mine ’s inherent and realized capacity. Realized capacity may be maximized through the optimization of soft factors such as the processes, behaviours, and organizational systems, controlling asset utilization, availability, and performance. Truck shovel dispatching systems revolutionized the utilization of mobile assets. High-precision global positioning systems (HP-GPS) are increasingly being adopted to optimize equipment performance. Real-time maintenance management systems have the potential to revolutionize equipment availability and significantly reduce cash costs. This paper explores some of the solutions available to mines to increase their inherent capacity and maximize their realized capacity.

Jan 1, 2004