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By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American?s suite of specifications for gearless mill drives (?GMDs?). These specifications are based on experiences in both Anglo American?s and others? operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Nov 1, 2011

By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American’s suite of specifications for gearless mill drives (“GMDs”). These specifications are based on experiences in both Anglo American’s and others’ operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Jan 1, 2012

By Harvey McLeod

M3 -Technology HOWEVER:In practice we have limitations ?Clients: aggressive or cost based; inexperienced ?Consultants: ?expanding market w/training limitations ?Prescriptive designs ?Lack of senior oversight ?Regulators: difficult to retain technical capacity ?Stakeholders: perceptions and expectations ?Physical settings: challenging terrain, climate, soils/rock Do M3?s Perform? YES?Generally M3?s since mid-1960 do perform ?BC Closed Mines: Afton, Highmont, Trojan, Bethlehem, Cheni, SNIP, NO?ARD/ML issues?e.g. Equity Silver, Samatosum; selenium, cadmium, sulphate

May 1, 2010

By Hajime Miki, Gde Pandhe Wisnu Suyantara, Shigeto Kuroiwa, Eri Takida, Tsuyoshi Hirajima, Masashi Yamane, Yuji Imaizumi, Mitsuru Sawada, Keiko Sasaki

Selective flotation of molybdenite and chalcopyrite using various oxidation treatments (i.e., ozone treatment, hydrogen peroxide, and Fenton-like reagent) was studied in this work. It was found that ozone treatment produced a depressing effect on both minerals, resulting in a lower separation of both minerals. On the other hand, oxidation treatment using hydrogen peroxide (H2O2) and Fenton-like reagent could deliver selective oxidation on chalcopyrite surface and depress its floatability. However, bench-scale copper- molybdenum (Cu-Mo) flotation tests show that oxidation treatment using H2O2 required a higher dosage of H2O2 and a longer treatment time in order to deliver comparable flotation results to that of conventional Cu- Mo flotation using NaHS treatment. On the contrary, Fenton-like reagent could deliver selective Cu-Mo flotation results comparable to that of NaHS treatment at a lower dosage of H2O2 and a shorter conditioning time. Contact angle measurements and X-ray photoelectron spectroscopy (XPS) analysis were employed to understand the depressing mechanism of these oxidation treatments. It was found that the chalcopyrite surface covered by various oxidation products that render the surface hydrophilic. Meanwhile, the surface of molybdenite was slightly oxidized, making the surface remained hydrophobic. INTRODUCTION Molybdenite (MoS2), the main source of molybdenum, is associated with copper sulfide minerals, mainly chalcopyrite (CuFeS2), as a trace mineral. Molybdenite is a valuable mineral and plays an important role in making the copper-molybdenum (Cu-Mo) processing plant economically viable (Laskowski, Castro, & Ramos, 2013). Therefore, it is important to recover molybdenite efficiently and effectively and separate it from copper minerals. Conventional separation of copper and molybdenum minerals is usually carried out in selective Cu- Mo flotation process using a copper depressant (i.e., sodium hydrosulfide (NaHS), Noke’s reagent, or cyanides) (Ansari & Pawlik, 2007; Bulatovic, 2007). However, this process still suffers due to imperfect molybdenum recovery. Moreover, the copper depressants use in this process are toxic and harmful to the environment. As alternative, various methods have been developed to replace these toxic and hazardous depressants, for example, by synthesizing new non-toxic or low-toxic depressants or by using various oxidation methods such as sodium hypochlorite in an alkaline medium, manganese dioxide, oxygen, and plasma pre-treatment (United States Patent Office Patent No. US 2559104 A, 1951; Patent No. US2238250 A, 1941; Barzyk, Malysa, & Pomianowski, 1981; Hirajima et al., 2014). However, the oxidation phenomenon and mechanisms are still not clear since detailed surface analyses have not done and the plasma pre-treatment method is facing technical issues for industrial scale application.

Jan 1, 2019

By V. Dinesen

"Grinding is simply the function of reducing particles in size or creating new surface areas. This may be accomplished by many means but we will only concern ourselves with the continuous grinding process as performed in a revolving drum or mill, containing a grinding media. Such a mill consists essentially of a feed head, a cylindrical shell section and a discharge head. To prevent internal wear of these parts it is customary to attach replaceable linings over the wear areas. The specification and design of these mill liners is more important than generally conceded. As they reduce the effective internal volume of the mill, they will consequently affect the whole mill ·design and operation.A number of mill designs of various sizes are available for combined crushing and grinding of materials within a wide size range. For simplif1cahon purposes we will refer 1n particular to conditions relating to standard mill shapes having a length which is greater than the diameter. Such mills usually rotate at speeds between 60% to 85% of the critical speed and may, depending on the grinding media used, be classified as rod mills, ball mills and pebble mills.LINER MATERIALSA great variety of materials have been and are being used for mill linings. These include wood, ceramics and cements, rubber and plastic compounds, rolled and forged steels, cast steels and cast irons, both plain, alloyed and specially treated.The choice of a liner material depends on many factors. In both dry and \\.:et grinding, it may be necessary to consider product purity, colour, chemical reaction etc. but for our purpose we \viii refer to wet grinding operations as generally used within the mining industry."

Jan 1, 1972

Session 1 ? Intro to MiHR ? Business Case for Aboriginal Inclusion ? Overview of the Mining HR Guide for Aboriginal Communities ? Two presentations of Programs featured in the Guide ?? The RAP Program from NWCC ?? First Nations Youth Employment Program PDAC-MM Session 2 ? Presentation from MAC ? Taking up the AFN Corporate Challenge ? Presentation on Mastering Aboriginal Inclusion in Mining About MiHR Who we are: ? National Sector Council for the Minerals and Metals Sector ? 18-person Board of Directors ? 100+ Industry Leaders volunteer on our project committees ? PPP - Funded by HRSDC and industry What we do: ? Identify national HR challenges and opportunities for the minerals and metals industry ? Create national solutions through collaboration, partnerships and Synergy

May 1, 2009

The control of carbon concentration in a counter current carbon absorption circuit is critical to optimise gold recovery. MINTEK has developed a carbon movement controller to address this potentially problematic area in gold extraction. This controller reduces operator interaction by automating carbon movement. Elution schedules are entered into the control system, which then moves the carbon through the circuit into the first adsorption tank until enough carbon is available for elution. This is done while maintaining the specified carbon profile within the circuit. MINTEK has also developed an online-carbonconcentration- meter to measure carbon concentration in pulp. The meter uses an ultrasonic measurement technique. Long term testing has shown the measurement to be robust and require minimal maintenance. Results from a gold mine in South Africa’s well known Witwatersrand gold producing area has shown a decrease in soluble gold loss between 30 - 50% when the controller was used.

Jan 1, 2014

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty type s. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk/ return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1988

By Sengpasith Houngaloune

Arsenic, which is a toxic and carcinogenic element, causes serious environmental problems throughout the world. It is also known as a major contaminant in the non-ferrous mining and extractive metallurgical industries, thus its disposal is one of the most important environmental issues for the mining and metallurgical industries. In order to ensure a safe disposal environment for the final wastes, stabilization of arsenic has been studied extensively with various approaches. Solidification/stabilization (S/S) represents one of the most effective methods to reduce the availability of arsenic in soil and waste by transforming toxic or potentially hazardous phases into less hazardous ones. Cement based S/S processes could reduce the solubility of arsenic in solid waste, using inorganic binders such as cement, lime, and pozzolanic materials. A new tailings management technique, called cemented paste backfill (CPB), has become widely employed for improving mining techniques and for tailing storage purpose and this technique could also enhance arsenic stabilization, by fixing the contaminants in the binder matrix. Disposal of arsenic in the form of scorodite (FeAsO4?2H2O) has been widely accepted as currently the most suitable method for stabilization and the safest known storage material. The Bio-scorodite process has been reported to be more economic and environmentally friendly method than the chemical crystallization processes. Retention of arsenic by schwertmannite (Fe8O8(OH)6SO4), a metastable ferric oxyhydroxy sulfate mineral, has gained more attention in the recent years. Schwertmannite has a large specific surface area and high capacity to adsorb arsenic in solution. Several researchers have reported that the transformation of schwertmannite to goethite could be retarded by the presence of adsorbed arsenic; therefore schwertmannite might be viable alternative for long-term storage of arsenic. In this paper, various approaches used in arsenic stabilization are reviewed with emphasis on the development in the recent years.

Aug 1, 2013

By C. Bissue, G. M. Castillo

Newmont’s Phoenix mine started production in March of 2006. Due to the extreme hardness of the ore, the mill has struggled to meet throughput projections. Grinding studies showed that optimizing the existing circuit would not achieve budgeted throughput. These studies also showed that the pebble crusher was being underutilized due to the inability of the SAG mill to break the rock. The concept was developed to supplement the feed to the existing pebble crusher with a secondary crusher. Models of this process looked favorable so a portable crusher was installed to test the process. The temporary crusher was successful at increasing the throughput by 7% and based on the operating data, plans are currently being developed to install a permanent secondary crushing system in front of the SAG mill. This paper will review the results from the test crusher and the flow sheet for the permanent secondary crusher.

Jan 1, 2012

"The Schist Lake mine, owned and operated by the Hudson Bay Mining and Smelting Co., Limited, is situated on the northwest arm of Schist Lake, 4 miles southeast of Flin Flon, Manitoba.The deposit was discovered early in 1947, during a diamond drilling program exploring small copper showings along the west shore of the lake. The orebodies came to surface between the mainland and the north end of Stitt Island.Production began in August, 1954, at an initial rate of 300 tons per day. Underground workings have been carried to the 1,700-foot level, where exploration work is now being done.General GeologyRocks of the area are Precambrian lava flows, with associated pyroclastic breccias and tuffs, and related minor intrusions. Their general strike is northwest and their dip is nearly vertical. Shearing is common and is related to the activity which caused intense folding and much faulting in the area. The larger faults and the fold axes trend a few degrees west of north. The lavas are mainly andesitic but a layer of sericite-carbonate schist, which is probably derived from a fine-grained, grey quartz porphyry, occupies most of Stitt Island and extends into the mine area. It is within this layer of schist that the ore deposit occurs (Figure 1).The OrebodiesThe ore occurs as tabular to lens-shaped bodies which strike northwest, dip nearly vertically, and plunge at 60 degrees to the southeast. The ore zone is 800 feet long and has been traced for a distance of 2,000 feet along the plunge (Figure 2). The maximum length of continuous ore within this zone is 200 feet. Widths of individual ore lenses vary from a maximum of 35 feet to a minimum of 2 feet.The ore consists of three distinct types: massive sphalerite-pyrite, massive chalcopyrite-sphalerite, and disseminated chalcopyrite-pyrite. The No. 1, or eastern, orebody is predominantly massive sphalerite-pyrite. The western part of the No. 2 orebody is massive chalcopyrite-sphalerite. The disseminated ore forms the eastern part and the lower end of the No. 2 orebody. All three types of ore, with patchy distribution, are found in the smaller lenses below the 1, 100-foot level.Metallic minerals, in order of deposition, are pyrite, arsenopyrite, chalcopyrite and sphalerite, galena, enargite, and gold. Both massive types of ore exhibit banding in many places, probably as a result of the selective replacement of schist. The disseminated ore was formed as a filling of the interstices in a brittle chert rock which appears to have been crushed by the same forces which produced the schist."

Jan 1, 1949

By G. Lee, E. T. C. Spooner

"Molybdenum mineralization at Boss Mountain is hosted by the Triassic Takomkane quartz monzodiorite batholith and is associated with a Cretaceous monzogranite stock. Ore has been mined from a sheeted vein system that describes a partial annulus centred upon the apical region of the stock and from subvertical breccia pipes that emanate from the stock. Molybdenite precipitation is coincident with CO2 effervescence from a dilute (1.9 mole o/o NaC/ equivalent) hydrothermal fluid over a temperature range of 250°C to 370°C at a pressure of approximately 350 bars, interpreted to be greater than or equal to the lithostatic load and equivalent to a depth of 1.3 km or less.IntroductionThe chemical and thermal constraints on molybdenum transport and deposition to form molybdenum ore deposits are not well understood. To address this problem, the Boss Mountain mine in central British Columbia, operated by Noranda Mines Ltd., was chosen as a well-described (Soregaroli and Nelson, 1976), relatively small and simple example of a Cordilleran Mo~ deposit. It is situated on the northeast slope of Takornkane Mountain, 10 km west of the community of Hendrix Lake (N.T.S. 93A/2W; latitude 52°06'N, longtitude 120°56'W). Access is from 100 Mile House by nearly 90 km of road, the first 50 km of which are paved."

Jan 1, 1995

By Steve Wilson, Bern Klein, Jeff Drozdiak, Stefan Nadolski, Andrew Bamber

"In the adaptation of high pressure grinding rolls (HPGRs) to hard-rock mining applications, circuit development has mainly focused on placing HPGRs in the role of tertiary crusher in the preparation of ball mill feed. In order to take advantage of the potential energy benefits associated with HPGR and stirred mill grinding technologies, work was done to investigate the potential of and resultant energy benefits of placing the HPGR in series with a high speed stirred mill in replacement of the conventional cone crusher / ball mill arrangement. The proposed circuit was designed to operate with two stages of HPGR grinding followed by high speed stirred milling.Using a pilot-scale HPGR unit inline with a 20 liter stirred mill, the design criteria, circuit arrangement and consequent comminution energy requirements for a circuit processing copper sulphide ore from Teck Resources’s Mesaba Copper project were determined. These results were then compared to two other circuits, an HPGR / ball mill circuit and a conventional crusher / ball mill circuit processing the same ore.The testwork indicated at a proof-of-concept level that the HPGR / stirred mill circuit could potentially be appropriate for this duty and further work on the concept is merited. While the results indicate that the HPGR component of the circuit was more energy efficient than conventional cone crushing, the energy efficiency of the stirred mill was found to be lower than that of a comparable ball mill undertaking the same duty. However, increased energy efficiency of the stirred mill portion of the circuit is possible with further optimization and further work on the concept is indicated."

Jan 1, 2010

By J. H. Nantel, J. F. Archibald

"The presence of radon from uranium-bearing ores, waste and from backfill material introduced underground to provide ground support, work platform and waste disposal functions, requires that ventilation controls be established to maintain safe working level concentrations. One approach has been developed at Queen's University to quantify radon and radon daughter source level s and to estimate ventilation requirements necessary to maintain these safe levels.Knowledge concerning the sources of radioactive contaminants and their production quantities is of value for planning and design stages of ventilation control systems. For any given mine layout, radiation level estimates may be forecast and modified by ventilation network design where excessive production quantities may exist.Behaviour of Radon Gas in MinesRadon gas, produced from the decay of Ra-226 in a host medium, will diffuse through porous media. In areas adjacent to mine workings, radon will be liberated into the mine atmosphere. The rate of radon emanation is proportional to the rate at which radon is produced within the host material (a function of the ore grade of U308) , to the radon concentration gradient in the host pores and to the diffusion properties of the material.The radon source concentration is determined by the rate at which Rn-222 is produced by the decay of Ra-226, and by the emanating coefficient (E), or fraction of the radon which escapes from the source matrix and is free to diffuse through the pore spaces."

Jan 1, 1984

By J. R. Eastwood

"H.D.P.E. Piping in the Mining IndustryThere has been much use· ms.de of high density polyethylene pipe in the mining industry over the past several years. This is not only in new installations but al.so in areas where other piping materials such as wood, transite, concrete and steel have worn out and failed.The uses of H.D.P.E. in the mining industry are as follows:Tailings disposal linesMine water supply linesTailings water return linesHydraulic backfill linesPit drainageCorrosive liquid supply and disposal linesH.D.P.E. pipe has many advantages for both underground and above ground installations. It is tough, flexible, weather resistant and inert which makes the pipe suitable for many installations."

Jan 1, 1975

By Alain Langlais, Caroline Boudrias Chapleau, Claude Bazin, Ahmed Bouajila

"Slurry «viscosity» has been recognised for several decades as a variable that significantly influences the operation of grinding mills. This paper describes an instrument that can be used in a laboratory or a plant to measure and monitor the flow properties of mineral slurries. Laboratory results obtained for two different ore samples are consistent with results obtained during a full scale trial. The results provide a basis for analysing the effect of the solids concentration and particle size distribution on the slurry flow properties. Grinding tests were also conducted in an attempt to link the grinding efficiency to the rheological properties of mineral slurries.INTRODUCTIONThe flow properties, or incorrectly called «viscosity», of a slurry influence the operation of mineral processing devices. Work has been conducted for instance to assess the effect of this variable on the operation of hydrocyclones (Kawatra et al. 1996; Klimpel, 1982a) and dense media separators for coal (Napier-Munn, 1996). However, most of the research effort has been oriented toward the grinding processes which is still the most energy demanding operation for ore dressing (Fuerstenau et al., 1995).Results of investigations of the influence of slurry flow properties upon grinding performances are presented regularly in the literature since 1950. In the 70's, most of the research work was conducted with the aim of using slurry flow properties for the control of grinding mill and to analyze the effect of that variable upon the population balance model breakage and rate functions (Austin et al., 1984; Hemmings et Boyes, 1977). In the 80's, most of the litterature dealing with slurry rheology was devoted to the use of viscosity modifiers to adjust the slurry flow properties, allowing an increase of grinding mill throughputs (Klimpel, 1982b; Fuerstenau et al., 1985). Although laboratory and pilot plant results show the benefits of adding these modifiers to the slurry, few plants have published results concerning the advantages of such addition (Fuerstenau et al., 1985). It is felt that the use of these modifiers introduce operating difficulties with the concentration circuits, especially flotation (Kawatra et Eisele, 1988)."

Jan 1, 2003

By Lynn M. Gould

Syncrude Canada operates the largest oil sands crude oil production facility in the world and produces over 13 percent of Canada?s total oil requirements. To do this, Syncrude mines the oil sand in open pits, extracts the raw oil known as bitumen from the sand using water-based processes and upgrades it into sweet light crude oil by fluid coking, hydroprocessing, hydrotreating and reblending. The final product, Syncrude Sweet Blend (SSB) is sent by pipeline to three Edmonton area refineries and then to pipeline terminals which ship the SSB to refineries in Canada and the United States. As parts of the Mildred Lake Base Mine reached their economic life, they were replaced with new facilities at the Aurora satellite mine. Aurora is situated on Oilsand Leases 10, 12, and 34, 35 kilometres northeast of the Mildred Lake facility. (Figure 1) In 2000 the first hydrotransport low energy extraction production train started up at Aurora. A second production train is scheduled for start up in 2003. Open pit mining at Aurora occurs using two hydraulic shovels, two cable shovels, and trucks ranging from 320 ton to 380 ton payload capacities.

May 1, 2002

By Robert B. Parsons

"With several hoots of the whistle, Canada's fiscal engineers are once again cranking up the income tax locomotive, in an effort to inject new stimulus into a stubborn economy. And once again, additional gears, wheels, levers, and other mysterious part s are being added to the already complex machinery in order to accommodate the new push.This time, a significant new mechanism involves a major overhaul and expansion of the investment tax credit system.Although the shiny new devices have considerable appeal to a certain group of potential passengers, one wonders if all of the renewed chugging and huffing is on the right track.IntroductionAs indicated in Tax Notes in the July 1983 issue of CIM Bulletin , the April 19, 1983 federal bud get introduced a number of new measures which would permit investment tax credits and research and development deductions to "" flow through "" from a corporation to another taxpayer."

Jan 1, 1984

By D. B. Dreisinger, M. R. Tavakoli

Vanadium has been produced from both primary and secondary sources having various compositions. Vanadium pentoxide and vanadium trioxide are the most available and known sources of vanadium oxides. In this paper, an overview of leaching both oxides has been reported. The problem of vanadium pentoxide leaching under acid conditions is the low solubility of the dissolved vanadium. This was investigated and then supplemented with further studies of leaching at mildly basic pH’s as well as under acid reductive leaching conditions (to form vanadium (IV)). Atmospheric oxidative leaching of vanadium trioxide was investigated using oxygen and ferric ion as the oxidant. It was shown that the leaching of vanadium trioxide using oxygen is very slow; however, ferric ion can dramatically increase the kinetics and leach efficiency.

Jan 1, 2014

By S. Koski, M. Schmalzel, D. A. Jacobson, S. Crosby, P. Cook, M. Mular

"Mining operations, whether new or existing, are constantly looking for ways to maximize production and improve energy efficiency, while keeping the footprint required to a minimum. The Nordberg MP1250 cone crusher was designed with these three goals in mind. A series of side-by-side evaluations comparing an MP1250 to an MP1000 were completed at two Freeport-McMoRan operations. The first evaluation began October 2009 in a tertiary position and the second began March 2010 in a secondary position, where it remains in full production today. Utilizing 25% higher power capacity than the existing MP1000 tertiary crushers, the MP1250 had 29% higher capacity and 17% lower specific energy, adjusted for differences in feed and product size. The MP1250 compared to the existing MP1000 secondary crushers achieved 30% higher capacity at a slightly reduced specific energy, while achieving a finer product.The MP1250’s higher capacity and energy efficiency may have application in many crushing plants. Depending on site specific economic factors, greenfield projects may benefit from a smaller footprint and less ancillary equipment, whereas brownfield projects may benefit from higher capacity or a finer product within the same footprint."

Jan 1, 2012