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"Air Products approached LAC Minerals in 1987 to initiate trials with pure oxygen in the leach circuit at several LAC facilities in Canada. This paper gives an overview of oxygen use and covers specific operating data from the Doyon and Terrains Aurifères mills near Val D'Or in northwestern Quebec. LAC also uses oxygen at the Macassa mill in Kirkland Lake, Ontario.In addition to the LAC facilities, oxygen is currently in use for test purposes at the Holt McDermott mine in Kirkland Lake, Ontario and the Camflo mine near Val D'Or.There are two requirements for oxygen in the cyanide leach mill. Firstly, oxygen is required in the familiar gold dissolution reaction as follows:(1) 4 AU (s) + 8 NaCN (aq) + 02 (aq)+ 2H 20(aq) - 4NaAu(CN) 2(aq)+ 4Na OH(aq)Of the reagents on the left side of the equation, the availability of gold is fixed by the ore in question. Obviously, water is available in excess, 1eaving cyanide and oxygen as the limiting constituents in the process. Most mills operate with an excess of cyanide, which is fairly closely monitored. Dissolved oxygen levels, however, are not normally watched very closely and find their own level based on the temperature, the availability of compressed air and the ability of the ore to consume oxygen.Typical D.O. levels are in the 3-8 ppm range, however levels less than 1 ppm are not uncommon for refractory ores.With pure oxygen, dissolved oxygen levels as high as 30 ppm can be achieved. (Figure #1). This greatly accelerates the kinetics of the leach reaction and may also shift the reaction further towards completion thus increasing gold dissolution slightly."

Jan 1, 1990

By K. E. Barnes

"The IsaMill was developed for fine-grained ores that required at least double the grinding efficiency of ball or tower milling to be economic. This was achieved, but in practice, the benefits of using inert media (eg sand, slag, ore, ceramic) have proven to be at least as important as the higher grinding efficiency. Flotation selectivity and rate was improved for all particles, particularly fines. This allowed a dramatic simplification of the Mount Isa lead zinc flotation circuit – adding 6 MW of ultrafine grinding power reduced reagent addition and flotation volume and increased plant energy efficiency. This was quite unexpected.This paper examines four orebodies that were enabled by inert grinding – McArthur River, George Fisher and Black Star Open Cut Mines (complex fine-grained lead zinc orebodies in Australia), and the Western Limb Tailings Retreatment plant (a PGM operation in South Africa). In a unique case history, the operating performance of the Mt Isa lead zinc concentrator is explained by size-by-size mineralogical data collected over 25 years, systematically explaining the impact of declining ore quality, and the effects of additional conventional grinding, inert grinding, and circuit and reagent redesign.The mineralogical case histories are so compelling that it is argued that the advantages of inert grinding should not be confined to difficult, fine-grained orebodies. The availability of largescale efficient inert grinding mills could have profound impact on circuit design for many orebodies.INTRODUCTIONThe IsaMill was developed by MIM (now Xstrata) to enable the development of the McArthur River Orebody in the Northern Territory of Australia. This ultra-fine grained ore needed a grind size of 80% passing 7 microns to produce a saleable concentrate. Such a fine grind was not economic with conventional ball or tower milling. Below about 25 microns the low energy efficiency and high media consumption of these mills is prohibitive. Critically, the high steel consumption and associated change in pulp and surface chemistry also seriously affects flotation metallurgy."

Jan 1, 2006

By P. Choquet, F. Miller

"The development and testing of a simple low-cost gauge for measurement of tension in a cable bolt grouted in a borehole are presented. Its principle is based on a resistance wire which is wound on a 70 cm length into the spiral grooves of the wire strand cable bolt. Readings are then taken by a robust automatic data logger with a several day autonomy or by a portable readout. In order to have a complete profile of tension along the cable bolt, a number of tension gauges can be installed along its length.This paper provides a description of the development and laboratory calibration of the tension gauge and addresses the two modes of loading for a cable bolt in a rock mass, namely pure tension and shearing at a joint location.In the second part of the paper, four field tests in underground and open pit mines are reported. The first test was used to substantially modify both the gauge and the readout unit principles while the other tests which are still on-going show a very satisfactory behaviour of the modified version of the tension gauge. IntroductionCable-bolting is often used as ground support in Canadian mines for a variety of applications. In underground mines, cable bolts can be installed vertically at the back of cut and fill stopes or in an inclined fashion in the walls of large open stopes. Alternatively, cable bolts at Mines Gaspe (Noranda Inc.) are used in a fan-shaped pattern from a drill drift to stabilize the inclined roof in 25 m wide open stapes. This new application oriented our research efforts toward the design of a novel instrumentation to monitor the efficiency of most commonly used 5/8-inch cable bolts."

Jan 1, 1988

By Neil McMillan

"By any measure of common practice, Claude Resources' Seabee Gold Mine in Northern Saskatchewan should not now be operating. Not because reserves dwindled, or grade dropped or prices weakened or technical problems arose, but because a host of unimaginable other problems beset the project, any one of which would normally have led to the mine's failure.The success of the Seabee Mine, and it is extremely successful, is a story of the vision and blunt determination of two men. Neither is remarkable in his own right but each possesses the characteristics which were necessary to forge a highly productive and profitable narrow-vein mine in the midst of the most bizarre and unpredictable events which likely have ever beset a mine start-up in Canadian history.Together, Bill MacNeill, a Saskatchewan born, former bush pilot and Ray Gagnon, a big hearted, hard-fisted, miner with 44 years of experience in Canada's underground, built the Seabee Mine.They didn't accomplish this with brilliant geology, outstanding engineering or nimble corporate manouvering but rather a stubbornness and raw common sense which likely are all too often, ingredients missing in failed projects.The Seabee Mine is 100% owned by Claude Resources, a Saskatoon based company taken over by Bill MacNeill, its current chairman, in 1982. The company is listed on the TSE and produces 1200 barrels of oil per day and about 60,000 oz of gold per year. The company has a strong balance sheet, is very profitable and has 18 million shares outstanding.The Seabee property in Northern Saskatchewan started out like many other gold exploration properties in Canada.It was discovered in the l 940's by what is now Cominco, and, while highly regarded by that company the property sat largely dormant until acquired by Claude Resources in 1985.Claude did what most junior exploration companies would do and went looking for a company with a depth of expertise to joint venture the property.That company was Placer Development who could earn a 55% interest in the Seabee by delivering a bankable feasibility study on the Project by July 1988 and providing financing to production.Placer Development was an excellent company and spent over $8 million dollars on the Seabee over a 3 year period. Unfortunately for Claude Resources, Placer Development merged with Dorne Mines in 1987 and the new merged company, Placer Dome, established a minimum production threshold greater than the 50,000 oz per year which the Seabee appeared capable of supporting at that time. Placer Dome's request for an indefinite extension of the joint venture agreement to allow it to drill off a larger ore body was rejected by Claude Resources and the Seabee Property was returned to Claude in 1988."

Jan 1, 1998

By E. M. Watkin

"Although Canada has achieved one of the highest living standards in the world, people and organizations have, over the past decade, begun to question the cost and means of this achievement. Concern has been expressed about the degree of environmental disturbance arising from industrial activities which have greatly contributed to our increased living standards. These industries include hardrock mining, pit and quarry operations, hydro-electric schemes, various agricultural enterprises and urban land developments.In the construction and operation of the above industries many environmental problems arise because the natural vegetative land cover is destroyed or drastically disturbed. Disturbance may occur to such a degree that revegetation is di ffi cult, often it appears impossible. Portions of the environment around such industries remain aesthetically unacceptable and appear to offer little or no potential for future resource use in wildlife, recreation or agriculture.The general public cannot dissociate itself from the activities of the aforementioned industries. It has, over many years, accepted the benefits and conveniences arising from those activities. Despite this, the increasing level of public concern imposes upon industry a need to alleviate or repair past, present and future environmental disturbance. Therefore it is incumbent upon industry to modify present technology or develop new techniques which would allow the disturbed environment to be easily and rapidly repaired."

Jan 1, 1975

By D. Brand

"The risk management objective of the AMIRA Code of Practice for Metal Accounting has seldom been systematically investigated in the literature up to the authors’ knowledge. Risk is defined in the Australian Standard on Risk Management (AS/NZS 4360:2004), as “the chance of something happening that will have an impact on objectives”. The simplified economic analysis performed in this paper has lead to define “something happening” as measurement non-representativity and “impact on objectives” as NSR loss from the optimal NSR. This has pinpointed a missing link being the establishment of a relation between NSR in flotation plants and measurement representativity. The proposed framework, referred to as the total cost of representativity, answers the previously unanswered question of how much accuracy/reproducibility is fit for purpose in a given flotation plant. Authors readily acknowledge that it is way easier to assess the cost of accuracy/reproducibility than the cost of inaccuracy/irreproducibility. However, this exercise not only answers previously unanswered questions but also establishes an essential link with operational excellence. This paper exposes why such operational excellence could neither be attained nor proved without a state of the art metal accounting system. This should impact not only how metal accounting systems are audited/designed/refactored, but also how flotation plants are designed.IntroductionBecause representative metal accounting is a vital source of information for the financial accounts of a mining/metallurgical company, the need for a code on metal accounting was recognized in 2001 and a team was formed in 2003, under the sponsorship of several major mining houses, to produce such a code. Table 1 exposes the two main objectives of this AMIRA Code of Practice for Metal Accounting."

Jan 1, 2017

By Clifford Britch

"Kaiser Resources Ltd. has completed feasibility studies resulting in approval of $277,500,000 for the construction of the Greenhills Surface Coal Mine, located 35 km north of Sparwood, B.C. The mine is designed to produce 1,800,000 tonnes per year of metallurgical coal over a 20-year period by conventional truck /shovel methods.The project is in the detailed design phase, with some preparation work being carried out on the site. The major construction activities are scheduled to commence in the spring of 1981. Mine development and pre-stripping will commence in July 1981, with first coal production scheduled for mid 1983.This paper will be a general description of the project and will include a discussion of the geology, reserves, mine planning, coal handling and processing, surface facilities and related topics.IntroductionProject DefinitionThe Greenhills Project is designed to produce, by conventional truck I shovel surface mining methods, 1,800,000 clean tonnes of metallurgical coal per year for twenty years . The production/ life constraints were chosen as being meaningful for planning and evaluation purposes after appraisal of the market potential and are not limited .by economic reserves. Substantial additional strippable reserves are available which would facilitate expansion of the proposed mine life and/ or capacity. In fact , all the facilities are designed so that they can be expanded in the future to accommodate a doubling of annual coal production, and certain portions of the coal processing facilities are being installed with an annual capacity of 3,600,000 tonnes. The mine will also produce approximately 2,400,000 clean tonnes of oxidized thermal coal, mostly in the first decade."

Jan 1, 1981

By J. Yue

"Mount Milligan mine is located in northern British Columbia. The concentrator employs conventional SABC grinding circuit with bulk sulphide flotation processes. Commissioning started in September of 2013 and nameplate production of 60,000 TPD was reached in the fourth quarter of 2015. As is typical with many mill ramp ups, bottlenecks developed as throughput increased. Since then, plant modifications and new control philosophies in the comminution and flotation circuits have been implemented and evaluated. The mine-to-mill collaboration played a key role in reaching target throughput rates by improving blast fragmentation and implementing temporary pre-crushing. Results of the projects as well as ongoing challenges/bottlenecks and solutions will be discussed.IntroductionMount Milligan Mine is a copper-gold producer located approximately 253 km northwest of Prince George in British Columbia. Production commenced in September 2013 and reached nameplate capacity of 60,000 TPD in December 2015. Average head grades for the mine life average 0.18% Cu and 0.39 g/t Au.Circuit DesignOriginal process design began with run-of-mine ore from the pit crushed through a 60-110 gyratory crusher, conveyed to a live ore stockpile and fed to the mill via four variable apron feeders. The concentrator circuit employs SAG mill - Ball mill - Pebble Crusher (SABC) grinding configuration to grind the ore down to a target P80 of ~200µm. It is then fed to two parallel trains of flotation tanks, each consisting of five 200 m3 tank cells with the first two being roughers and last three being scavengers. Concentrate streams from roughers and scavengers are separately reground with a closed circuit Tower mill and two open circuit ISA mills operating in parallel, respectively.Three stages of cleaners upgrade roughers/scavenger products to 25% Cu followed by a cleaner scavenger stage. The final concentrate is then thickened and filtered to approximately 9% moisture and shipped off site (Figure 1)."

Jan 1, 2017

By L. C. Bird, N. T. L. Landgren, M. W. Mikhail

"Through funds made available in 1972 by the Nova Scotia Department of Mines and Energy (DME) and the federal Department of Regional Economic Expansion, a program was initiated to recover saleable coal from mine waste dumps adjacent to the existing Acadia wash plant in Stellarton, Nova Scotia.Following evaluation of these dumps in 1972, the Acadia wash plant was modified to treat high-ash material. The first production was recorded in late 1974. By the end of 1979, a total of 738,202 t of dump material had been processed, yielding a total of 205,212 t of thermal-quality coal.The successful Stellarton operation led to considering the possibility of recovering thermal coal from other dumps. Evaluation of the Westville dumps indicated total recoverable reserves of 1,346,617 t averaging 53.8OJo ash.Parameters for plant design were defined from the washability characteristics of the dump material and the results of a bulk test. Two options were proposed; one was to use the existing plant with some modifications, the other was to build a modular mobile plant that could be used at future dump sites in the province after Westville. At the 25% ash level, the potential recovery of coal from the dump was estimated at 41% yield (by weight) or 549,679 t."

Jan 1, 1981

By Wm Petruk

"The tungsten-bismuth-molybdenum deposit in southwestern New Brunswick occurs in greisenized and silicified tuffite * and feldspar porphyry in and adjacent to volcanic necks. The ore minerals occur as veins and veinlets and as disseminated grains in gangue. These minerals can be grouped into three assemblages. Assemblage 1 consists of oxides and phosphates of W, Ti, Fe, Nb, Sn, Ta and rare-earth elements, with the main minerals being deposited in the sequence wolframite, rutile, cassiterite. Assemblage 2 consists of arsenopyrite, molybdenite and bismuth, and assemblage 3 of sulphides with minor cassiterite and arsenopyrite. Sphalerite is the main sulphide mineral, but it contains minute inclusions of copper-tin- and indium-bearing minerals. Textural relations suggest that most of the elements can be recovered from this ore by conventional mineral beneficiation and extraction methods, but a variety of techniques must be employed. It is expected that the wolframite and molybdenite can be recovered satisfactorily, but poor recoveries are expected for bismuth and cassiterite. A sphalerite concentrate can be readily obtained by flotation, but it would contain a wide variety of elements. It is suggested that leaching be used to recover the bismuth and the elements in the sphalerite concentrate."

Jan 1, 1973

By K. D. Hester

"1.0 INTRODUCTIONThe uranium industry started in Canada with the reopening of the gravity concentrator at Eldorado's Port Radium mine in the North West Territories in 1942. In 1948, uranium exploration and processing was opened to the private sector, and the Federal government offered special pricing incentives to the industry. Eldorado explored the Lake Athabaska deposits in northern Saskatchewan, and in 1953 opened the Beaverlodge mine. Other mines in the area soon followed. In 1953 also, the deposits in the Blind River - Elliot Lake area and in the Bancroft area of Ontario were discovered. Mines and mills were quickly developed in these areas.Canadian uranium production peaked at 15,900 short tons of U3O8 in 1959. In that year, uranium exports at $300,000,000 exceeded those of all other minerals in value. On October 1, 1959, Canadian uranium operations employed 13,900 people.Up to 1956, it was a seller's market. By 1958, world production of uranium was far ahead of requirements. Accordingly, in November of 1959, the USAEC announced it would not renew it's options for continued delivery of uranium from Canadian mines. This led to the ""stretchout"" of existing uranium contracts, and many mines were shut down (see Table 1) .In the early 1970's, a commercial uranium market seemed to be developing. In Ontario, at Elliot Lake and Bancroft, mines reopened. But competition was coming from the Athabaska basin of Saskatchewan. Currently it is these high grade, open pit deposits of northern Saskatchewan which are in the forefront of Canadian uranium developments. Canadian developments since 1942 reflect the political and market forces, as well as metallurgical progress and changes in environmental standards. This paper attempts to show these process changes in broad perspective."

Jan 1, 1987

By M. Churchill, V. R. Degner

"Over the past two decades, declining ore body grades, increased operating costs and increased construction costs have provided an incentive for the development of progressively larger flotation machines. As a consequence, the 60 to 100 cubic foot flotation machine of the l950's and l960's is being rapidly replaced by large volume machines, with a resulting improvement in the flotation machine specific capacity (TPH processed per square foot floor space), specific power (HP per TPH processed) and process control simplicity. The recent development, and satisfactory plant evaluation, of the WEMCO 1000 cubic foot flotation machine provides the means by which further economic and operating advantages may be incorporated in high tonnage mill applications.The systematic development of the large 1000 cubic foot flotation machine, and its subsequent performance evaluation in beneficiating metalliferous ores (copper, zinc and iron) will be reviewed in this paper and recently completed plant results will also be provided."

Jan 1, 1982

By T. R. Raponi

"The Williams Mine, Canada's largest gold mine, processes over 6,000 t/d of ore utilizing SAG/ball milling, leaching and CIP, carbon stripping, electrowinning and refining to produce gold dare bullion.Grinding accounts for over 50% of milling costs with grinding media, power and mill liners making up over 75% of grinding costs. Since 1991, several changes in these areas have been made which have significantly reduced costs, while fineness of grind and mill recovery have both been increased.This paper discusses the changes made in the grinding circuit over the past few years and assesses their impact on operating costs and mill operations.IntroductionThe Williams Mine is located in the Hemlo area of northwestern Ontario, about 40 km east of Marathon. It is operated by the Williams Operation Corporation, which is equally owned by Teck Corp. and Homestake Canada Inc. Canada's largest gold mine, the Williams Mine commenced operation in October 1985 at a rate of 3, 000 t/d. Mill throughputs have typically exceeded design, averaging 3, 397 t/d in 1986, and 3,380 t/d in 1987. In August 1988, production was increased to 6,000 t/d. Throughput averaged 4,212 t/d in 1988. Production increased over the next few years averaging 5,477 t/d in 1989, 6,248 t/d in 1990, 5,987 t/d in 1991, and 6,283 t/d in 1992. With a recovery of over 95.5%, production for the first three quarters in 1993 is averaging 6,408 t/d.GeologyThe main ore body is a steeply dipping conformable zone of microcline-quartz-muscovite rock. It occupies the contact zone between hanging wall metasedimentary rocks and foot wall felsic quartz feldspar porpyritic rocks of possible volcanic or subvolcanic intrusive origin. The ore body is enveloped by muscovite schists which are thickest on the footwall side. The schist is enriched with tourmaline, pyrite, and green mica containing vanadium and barium. The ore body contains pyrite and barite which occurs mostly in laminae and bands to veinlets and breccia fillings. The gold occurs as free (native) grains, 20 to 30 µm in size at grain junctions of the microcline and quartz. Visible gold is rare in the main zone. There are commonly two or more discernable layers of economic value which are separated by weakly gold mineralized material which usually consists of muscovite schist, barite rich zones or sulphide poor-microcline-quartz rock and in the upper and western fringes by biotite rich schist with feldspathic fragmental characteristics. Molybdenite is a common constituent as very fine disseminated grains in the microcline-quartz rock and is most prominent with gold enrichment. Stibnite and realgar are two of the more common accessory sulphides."

Jan 1, 1994

By Y. L. Su, S. Vongpaisal, H. A. Smith

"It is extremely difficult for a mine's central control room operator to control peakpower demands and to maintain normal materials handling operations at the same time. An investigation of the Falconbridge Strathcona Mine 's central control room has revealed that there are more than eight thousand possible combinations of ""situations"" that can arise. For such a circumstance, an expert system can become a very valuable tool to assist the operator in taking the most appropriate and timely action.A forward chaining expert system module has been developed for this application. The module is based on Level 5 ObjectTM software. It is graphics oriented and user-friendly. Training requirement is minimal.ForewordThis paper has arisen out of work carried out by YLS Associates and Falconbridge Limited as part of a contract between Falconbridge and the Department of Energy, Mines and Resources, Government of Canada, on the application of expert systems in mining operations.IntroductionThe electrical bill charged to large consumers by Ontario Hydro is based upon two elements: demand and energy consumption. The demand is the peak kilowatt level that the consumer has required during a monthly period. It is not uncommon for the demand portion to be as much as one third of the monthly bill. Energy consumption is the total kilowatt-hour s (kWh) consumed during the period.Ways to reduce the energy consumption part of the electrical bill involve utilizing energy-efficient equipment and operating machines in off-peak hours when a lower energy rate is charged. Maintaining the peak power below a critical level may require that simultaneous usage of major pieces of equipment be avoided. A 3000 kW skip run at an inopportune time could cost a company an extra $30,000 in that month's power cost.Potential disadvantages associated with peak power control are lost production due to work stoppage and increased operating costs due to the need to employ extra personnel. Most companies find these matters relatively easy to deal with and with incentives provided by Ontario Hydro, actively pursue this facet of energy savings (Harju , 1991)."

Jan 1, 1993

By Jan E. Nesset, James A. Finch, Frank Rosenblum, Rebecca Payant

"Under certain conditions of moisture and oxygen, sulphides can spontaneously heat, a phenomenon known as self-heating. In this paper, we test a hypothesis that galvanic interaction between some sulphides can promote self-heating. Galvanic interaction is controlled by restpotential difference between minerals and their surface area of contact (particle size). In order to decrease rest-potential, four sulphides were tested: pyrite, chalcopyrite, sphalerite and galena. Two series of samples consisting of mixtures of two sulphides, each representing a mass fraction of 50 %, were run in standard self-heating tests. The first series comprised five mixtures, two with low rest-potential difference (pyrite-chalcopyrite and chalcopyrite-sphalerite) and three with high rest-potential difference (pyrite-galena, chalcopyrite-galena and pyrite-sphalerite). The second series was performed on a pyrite-sphalerite mixture at four particle sizes (80 % passing 850 µm, 300 µm, 75 µm and 38 µm). The first series showed that the individual sulphides and the mixtures of low rest-potential difference did not self-heat but the mixtures of high rest-potential difference did self-heat. The second series showed that self-heating increased inversely with particle size (increased specific surface area) and revealed that it was the fineness of the pyrite (high rest-potential sulphide) that governed the self-heating effect, indicating the rate-limiting step is the reduction reaction on pyrite (cathodic mineral). The increase in self-heating with high rest-potential difference and increasing particle fineness supports the hypothesis that galvanic interaction contributes to sulphide self-heating. A possible mechanism based on the hydrogen sulphide hypothesis is proposed where the reduction reaction at the cathodic mineral surface is ferric to ferrous. The understanding gained will be of interest to those involved in storage, shipping and disposal of sulphide minerals.INTRODUCTIONSulphide mineral ores are the major source of most base metals such as copper, zinc, nickel and lead. Once the ore is extracted, the sulphide minerals are liberated by size reduction (crushing and grinding), concentrated by flotation, and the concentrates sent for further processing to extract the metal (smelting and refining). At the various stages from mining to concentrate shipment and tailings storage, the sulphides are exposed to a variety of environments, which under certain conditions of air (oxygen), humidity and temperature can cause them to heat. Since no external heat source is involved, this pyrophoric process is known as spontaneous heating or, more commonly, self-heating. The self-heating of sulphides is associated with oxidation reactions under moist conditions. If the heat generated is greater than the heat dissipated, the sulphides will self-heat and the material temperature will rise. This can make working conditions potentially dangerous as oxygen is consumed from the surrounding air and significant quantities of sulphur dioxide (SO2) can be released (Ninteman, 1978)."

Jan 1, 2011

By G. K. Jorgenson, S. H. Chung

"IntroductionThe SABREX Blast Modelling Program was developed jointly by the companies of the ICI Explosives Group, of which C-I-L Inc. is a member. SABREX (Scientific Approach to Breaking Rock with Explosives) is a modular computer program which incorporates new technology with a number of tested programs that have been in use world wide.SABREX predicts the performance of blasts in terms of (I) fragment size and distribution; (2) muckpile profile and face velocity; (3) grade fracture; (4) collar breakage; (5) a rupture envelope which depicts crack penetration behind and beneath blastholes; and (6) a complete cost analysis including explosives, drilling and accessory costs. The predicted blast results are displayed as dynamic colour graphics and in tabular form.SABREX uses data on the detailed geometry of the drilled and loaded pattern, detonation characteristics of the explosives and the dynamic properties of the rock to generate blast predictions. SABREX blasting calculations take into account the effects that shock and quasi-static pressures exert on the rock around the blastholes. While physical effects occur very rapidly in rock blasting, it is possible to view and model the sequence of events as discrete sections.The program can be run on a microcomputer and is currently operated by C-I-L technical service staff in Canada for the use of drilling and blasting operators.Figure I is a diagram representing the modules of the program and associated technology that is used to complement the program.Any, or all, of the modules may be used in a particular study or blast optimization. Because the BOBCAT module of the SABREX program has been described in previous papers(7.8.9), this discussion will concentrate on the newer modules: CRACK, HEAVE, RUPTURE ENVELOPE and to a limited extent, KUZ-RAM, which present a more detailed picture of the blasting process.Each of these modules is discussed in terms of the information they offer the operator in analyzing the blast. Specific examples of recent usage in Canadian mining situations are included to illustrate the ability of the model to produce practical results that can assist in optimizing actual blasting operations or solving problems that do exist."

Jan 1, 1987

By P. J. Noakes

Remote and isolated, located in a frigid, hostile environment, the Black Angel mine in Greenland had to create a warm social environment which would help attract and retain a stable work force of miners and support staff. The high cost of personnel turnover plagues many mines and, when the mine is inside the Arctic Circle, accessible by helicopters which are highly vulnerable to unpredictable weather conditions during the long, dark winters, the potential costs of personnel turnover become critical factors in the success or failure of the mining venture. Manpower planning should start from the date the engineers begin the technical design of the new mine. The plan should include provisions not only to ensure an adequate, skilled work force, but also to ensure a stable work force of people who are happy enough in the mining environment to want to remain, take their vacation and return to work at the mine. The skilled work force was assured with training courses of four months, designed to produce highly specialized underground workers from unskilled Danes and Greenlanders supported by trained Swedish and other Scandinavian miners. The stable social unit was assured by plans the primary attribute of which had to be flexibility. The accommodation changed from shared accommodation with communal washroom facilities to single accommodation with private washroom facilities. A recreational director was hired to help the workers make use of elaborate recreational facilities. A closed-circuit TV and radio system was installed to operate as a private broadcasting system using taped programs originally broadcast on European TV networks or developed by the mine personnel themselves. The liquor rules were changed and the mine manager became a licensed innkeeper responsible for the orderly operation of the Black Angel Bar in accordance with the Danish laws governing the services of a public bar. The result is a relatively stable work force. Some 35% of the people have more than two years' service with the company, Greenex A/S, and some 62% complete 10 months of service.

Jan 1, 1978

By Brad Sampson

Project Ownership ?Discovery Metals Limited ?ASX (DML), BSX (DML), AIM (DME) ?Market Cap AUD 195M ?Key assets ?Boseto Cu ?Dikoloti Ni The Boseto Copper Project ?Location ?Setting ?History ?Status ?Future

May 1, 2010

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 Y. Faitakis

In the mining industry, maintenance is a key priority and a major expense. As mining equipment is large in scale, high in cost, and difficult to tow, it is key to maintain equipment on a timely basis. Breakdown in -40°C or away from a maintenance station can cause great costs in repair as well as lost production. It has often been quoted that about 5% of the North American production is lost every year due to unscheduled downtime. About one-third of the downtime is attributable to equipment failures. From this fact alone, it is evident that proper equipment maintenance can add tremendous value to the bottom line. As organizations and equipment become more sophisticated, maintenance expectations begin to evolve. This evolution can be traced through three generations: The first generation (1940?1950): A ?fix it when it broke? attitude prevailed during that time, mostly because the industry was not highly automated. The second generation (1950?1980): Automation and mechanization of the industry increased. The industry now was dependent on machines performing the majority of the work. Preventive maintenance (overhauls at fixed intervals) appeared as the first maintenance practice. Maintenance costs started to rise rapidly. The third generation (1980?): Assets become more complex. Failure modes are better understood and computerized maintenance methods are becoming mainstream. Condition-based maintenance (CBM) starts to gain ground as a cost-effective alternative, replacing the fixed interval overhauls. As corporations amalgamate and market places are becoming more complex, multi-functional teams become responsible for maintenance. At the beginning of the third generation, maintenance organizations began embracing technology to provide efficiencies in maintenance management. A strong push was made to transition from reactive maintenance to proactive maintenance. At the forefront of this push is condition-based maintenance.

Jan 1, 2004