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By Hiroaki Sakurai

Using batch reactors equipped with CO and CO2 gas sensor, CO oxidation over Au catalysts in room air has been investigated and compared with Pt catalysts. For both Au and Pt catalysts, the logarithm plot of CO concentration data during initial 10 min are well fitted by straight line, which mean the first order dependence on the CO concentration between 10 and 10,000ppm. The rate constant value (k) over Au and Pt catalyst generally decrease with increasing initial CO concentration above 100ppm. The value decrease especially rapidly between 100ppm and 1,000ppm over Pt catalysts, which should be due to the strong adsorption of CO on Pt. The k value over Au catalyst has become ten times or more as large as the Pt catalysts at 1,000ppm. Already for the initial concentration of 100ppm CO, the strongly adsorbed CO on Pt metal has been clearly observed by FT-IR during the reaction over Pt/Al2O3. A part of the strongly adsorbed CO has been remained on Pt after the disappearance of gas phase CO, and has gradually changed to gas phase CO2. Such strongly adsorbed species on Au has never been observed on Au/TiO2 under the same reaction conditions. These features of Au catalysts are favorable for indoor air purification.

Oct 1, 2003

By James L. Oleson, Hunter R. Propsom, Kevan J. R. Ford, Robert D. Henderson, Bob Musgrove

"Kinross’ Fort Knox Gold mine, near Fairbanks, Alaska has successfully implemented two major metallurgical continuous improvement projects resulting in growth of gold production and an extension of mine life. In 2009, Fort Knox produced 263,153 oz of gold at a cash operating cost of $543/oz. In 2010, approximately 63% of the gold will be produced from the CIP circuit, 15% of the gold from the gravity circuit and 22% of the gold from the heap leach.In 2009, a 44,000 ton per day run-of-mine valley fill heap leach facility was constructed and commissioned as a cost effective treatment option for low grade ores to supplement the higher grade mill. The heap leach facility will produce approximately 100,000 ounces of gold per year under severe winter conditions. Heap leach gold recovery, based on test work shows 30% after a 55-day leach cycle, with long term ultimate gold recovery targeted at 65%. The paper presents the heap leach design concepts and production data.Additionally in 2009, installation of a Knelson gravity concentrator unit (XD70) was completed. This together with an Acacia intense leach reactor (AILR) has increased overall mill gold recovery from 79.3% to 80.7%. A manual shaking table gold recovery operation has been replaced by batch intensive cyanidation of the high grade Knelson concentrates. Increased removal of coarse gold and difficult-to-leach gold species from the grinding circuit, via the gravity circuit, has improved gold leach recovery in the conventional whole-ore tank leach CIP circuit. The paper presents plant operating data, showing the improvements over the old flowsheet.Focus on the metallurgical properties of the high grade and low grade end components of the Fort Knox ore has resulted in significant improvement to gold recovery."

Jan 1, 2011

By David W. H. Ellis

This presentation will discuss over 2 dozen past, present and future oils sands projects in Alberta. The very early projects as well as the most recent along with the ones that never got off the ground and the ones in production are all included. For each, the following will be given (where known): owners, location, type (mining/SAGD/refinery), production, capital budget, spent to date, status. Some overall impacts will be discussed.

May 1, 2004

By Todd Smith, Brigitte Lacouture, Greg Anderson, David Lin

"The lead and zinc flotation circuits at Red Dog Mine are preceded by a preflotation circuit which recovers naturally-floating organic carbon contained in the ore. Organic carbon is a potential contaminant in the lead concentrate and is detrimental to lead-zinc selectivity. Prior to 2007, the Red Dog preflotation circuit consisted of a single stage bank of tank cells which floated the organic carbon. The preflotation concentrate was discarded directly to tailings, however, this stream contained significant amounts of lead and zinc. Zinc loss to preflotation ranged from 2% to 6%, relative to the zinc in the mill feed and was proportional to the amount of organic carbon in the ore. The main mechanism of the zinc loss was entrainment.Pilot plant and modeling testwork were conducted to examine the use of a Jameson Cell to clean the preflotation concentrate. Results indicated that up to 90% of the zinc deporting to preflotation concentrate could be returned to the flotation circuit for recovery. The installation of a 5.4 m Ø Jameson Cell with 18 downcomers was initiated in June 2006. The new preflotation cleaning circuit was commissioned in March 2007. Conservatively, preflotation cleaning has resulted in zinc and lead absolute recovery gains of 1.0% and 1.5%, respectively. The $9.1M project has a payback period of approximately 1 year at current metal prices.INTRODUCTIONRed Dog Preflotation CircuitRed Dog Mine is located above the Arctic Circle in northwest Alaska. It is the world’s largest zinc concentrate producer with a production rate of more than 1.0M t/yr. Red Dog is operated by Teck Cominco Alaska Incorporated under an operating agreement with the Northwest Alaska Native Association (NANA). Due to the remote location of the mine, it is accessible only by air, or seasonally, by ocean-going barges.The Red Dog deposit is a rich sedimentary exhalative (sedex) zinc-lead-silver deposit. The major sulphides, in decreasing order of abundance, are sphalerite, pyrite, galena and marcasite. Due to the complex nature of the ore body, run-of-mine ore is blended in stockpiles before being crushed and processed through the concentrator. The average mill feed grade for 2006 was 6.1% lead, 20.6% zinc, 8.0% iron and 0.67 % organic carbon."

Jan 1, 2008

Operations and maintenance departments have had a long-standing adversarial relationship. The widespread evolution and adoption of modern management techniques, such as reliability centered maintenance (RCM) and Lean, however, has driven interest in working co-operatively to optimize overall plant performance. Mining and minerals operations have long adopted RCM in maintenance and are now adopting Lean throughout organizations. Such modern management initiatives explicitly call for co-operation between the two disciplines of maintenance and production and many advances have been made in terms of people and methodology. One area that has lagged behind in supporting these developments, however, is information systems. Enterprise asset management (EAM) systems in maintenance and newer manufacturing execution systems (MES) in operations have not been truly integrated in the needed ways. Complicated plants, different software architectures, continually changing conditions and many other variables have led to systems problems, which have contributed to the maintenance/operations divide. Master data synchronization (the plant tree) and integrated reporting of real-time data with transactional data are just two of the issues that are being solved by new approaches in information technology, including web services and service orientated architectures. New technologies are coming on-stream to enable the final bridging of the gap.

Jan 1, 2009

By Joe Holmes, Peter Langlois

"Falconbridge’s Raglan Concentrator, located at the northern limit of Quebec’s Nunavik Region, has been in operation since December 1997. Originally designed to process 800,000 tonnes per year of high grade nickel ore, plant capacity is currently approaching 1,000,000 tonnes per year. Optimization of the ABC grinding circuit has proven to be the most challenging component of this capacity increase. Concurrent flotation circuit modifications have allowed concentrate grades to increase from 16 to 18 percent nickel, while maintaining recoveries. Concentrate drying problems encountered during the first 15 months of operation have been addressed through equipment upgrades. The challenges associated with surface deposition of filtered tailings in an arctic environment are now better understood, and detailed design of the progressive reclamation cover is underway.GRINDINGCircuit OverviewOre from open pit and underground mining operations is introduced to the underground ore handling system via surface and underground truck dumps. Two underground bins with a combined capacity of 4000 tonnes provide roughly a day of live capacity for ore storage. Ore from the two bins is conveyed to a 150 tonne surge bin immediately ahead of the grinding circuit in the concentrator.The Raglan grinding circuit has a conventional ABC configuration (Figure 1) with a design capacity of 100 mtph (800,000 tonnes per year). The 24’ AG mill is powered by a 3000 hp motor with variable speed drive. AG discharge is sized on a 8’x16’ single deck vibrating screen, with screen oversize recirculating to a 5 %’ short head cone crusher (400 hp) before returning to the AG mill. Screen undersize is combined with ball mill discharge to feed up to 5 15” Krebs hydrocyclones. The ball mill is a 14’x 21’ overflow mill driven by a 3000 hp motor at 73% critical speed. Target Pgo for the grinding circuit product is 65 microns"

Jan 1, 2001

By J. Sammut, T. G. Joseph, R. Andreev, M. Curley

"Decisions regarding mining method and subsequent choice of excavator must take into account the quantitative factors of productivity, availability, and capital, operating, and maintenance costs. Dig performance was compared between a hydraulic excavator (HE) and electric rope shovel (RS) of similar size class (i.e., use the same amount of energy to excavate a unit quantity of the same material from a mining face), focusing on the quantitative factors above. Machine performance, normalized to bucket capacity, was assessed as a function of hours of service (60,000 hours per machine). Results showed higher production rates for the HE of similar capacity and age. In general, the RS exhibited lower service cost per volume capacity, though it had higher capital cost. The RS became more cost effective than the HE of similar capacity within approximately 30,000 hours of service. ¦ KEYWORDS Cost, Electric rope shovel (RS), Excavation, Hydraulic excavator (HE), Surface mining RÉSUMÉ Les décisions concernant la méthode minière à adopter et le choix ultérieur d’un engin d’ex¬cavation doivent tenir compte des facteurs quantitatifs de la productivité, de la disponibilité ainsi que des coûts d’investissement, d’exploitation et d’entretien. Cette étude compare les performances en termes d’excavation d’une excavatrice hydraulique et d’une pelle électrique à câbles de même taille (qui utili¬sent par exemple la même quantité d’énergie pour creuser une quantité unitaire du même matériau dans un front de taille), en se concentrant sur les facteurs quantitatifs susmentionnés. La performance de la machine, normalisée à la contenance du godet de volume unitaire, est évaluée en fonction des heures de service (60 000 heures d’activité par machine). Les résultats montrent des taux de production plus élevés pour l’excavatrice hydraulique d’une capacité et d’une ancienneté similaires. De manière générale, la pelle électrique à câbles affiche un coût d’entretien par capacité volumique inférieur, mais son coût d’in¬vestissement est plus élevé. La pelle électrique à câbles devient plus rentable que l’excavatrice hydrau¬lique d’une même capacité au bout d’environ 30 000 heures de fonctionnement. ¦ MOTS CLÉS coût, excavation, excavatrice hydraulique, exploitation à ciel ouvert, pelle électrique à cablesINTRODUCTION The most common excavating tools in surface mining operations are the hydraulic excavator (HE) and electric rope shovel (RS). In general, electric RSs are more reliable and cheaper to maintain (P&H Mining Equipment, 2007), but where complicated geological conditions exist, HEs are preferred because they are generally considered to be more mobile."

Jan 1, 2019

By J. E. Udd

"In early 2000, CANMET-MMSL was engaged by the Ontario Ministry of Labour (OMOL) to conduct an international study of the practices, in several key mining jurisdictions, of determining the criteria that are used to decide when the wire ropes used in mine hoisting are to be retired from service. Subsequently, the author visited key officials and institutions in Canada, the United States, the Republic of South Africa, the United Kingdom, Germany, and Poland. Material from the Australian province of New South Wales and Hungary was also included.The report that resulted included, among other sections: (1) the history of wire ropes and trends in manufacturing technology; (2) a review of mine hoisting practices; (3) the requirements regarding safety factors; (4) a review of the various operations and their potential future development; (5) the criteria for rope replacement; (6) potential future developments that could take place in both hoisting and rope inspection practices in Canada; and (7) recommendations.Subsequently, the report was issued by OMOL, and as a CD-ROM by CANMETMMSL. In this paper the author presents the key findings and the recommendations made in the study."

Jan 1, 2004

By Chuck Edwards

"Milling operations in northern Saskatchewan’s Athabasca Basin have produced uranium continuously since 1975. Over that period, the Athabasca Basin has been one of the world’s premier uranium camps, yielding more than 660 million lb of U3O8. In this paper, the author describes former and current milling operations and discusses why and how the milling process has changed and developed over the past 35 years. The author’s considerations for the future of uranium extraction in the Athabasca Basin close out the paper.INTRODUCTIONThe roughly oval Athabasca Basin in northern Saskatchewan occupies nearly one third of the surface area of the Saskatchewan Shield. Its sandstone-like deposits lie unconformably on the older basement. The basin hosts many high-grade unconformity-type uranium deposits(Saskatchewan Energy and Resources, 2010) for which the Athabasca Basin is world famous. Uranium production in the Athabasca Basin has come from four mills. In the order of startup these are Rabbit Lake, Cluff Lake, Key Lake and McClean Lake. General data (AREVA, 2010; Cameco, 2010; Denison 2010) for each mill are shown in Table 1."

Jan 1, 2011

By G. M. Hughes, J. Ellis

"IntroductionHydraulics has been considered a science for thousands of years. Applications included water wheels, dam; and slice gates but today the term ""hydraulics"" commonly refers to ""power hydraulics"" in which fluid is used under controlled pressure to do work. The mining industry employee’s hydraulics in practically every aspect of its operations, on such equipment as trucks, front end loaders, LHD units, crushers and hydrostroke feeders. The many benefits of hydraulic drives such as ease of variable speed control, high power: weight ratio low envelope size of hydraulic actuators and ease of maintenance have been extensively developed in the pulp and paper, chemical, steel, and other basic industries, but until quite recently, concentrator operators have not taken advantage of the versatile methods of power transmission offered by hydraulic systems.After some preliminary testing at the Lynn Lake concentrator Sherritt Cordon Mines Limited installed several hydraulic system; at their Fox Mine concentrator to drive slurry pumps and conveyors. The systems used at Fox and the systems which will be installed at the Ruttan concentrator are briefly described in this paper. Since acceptance is based mainly on understanding a few basic principles of hydraulics system; including pumps, motors, circuitry and central methods are also presented in the paper.PRINCIPLES OF POWER HYDRAULICSBasicsHydraulic systems provide an uncomplicated, versatile means of power transmission. The basic system is quite simple. It consists of five main elements, as shown in Figure 1, which are:1. Prime Mover - generally an electric motor.2. Hydraulic Pump - fixed or variable positive displacement type such as a piston or vane p.mp which displaces a constant amount of fluid for ead1 revolution - this unit converts mechanical energy of the prime mover into fluid energy.3. Oil Reservoir - a standard tank to operate under atmospheric pressure which has a capacity of 2 - 3 times the maximum gpm outp.it of the hydraulic pump."

Jan 1, 1972

By Virginia T. McLemore

The Gallinas Mountains are in northern Lincoln County and southern Torrance County, New Mexico, USA where a series of alkaline igneous bodies, including porphyritic latite, trachyte/syenite, andesite, and rhyolite laccoliths, flows, dikes, and plugs, have intruded Permian sedimentary rocks belonging to the Permian Abo, Yeso, and Glorieta Formations. A small amount of bastnaesite, a REE mineral, was recovered during processing for fluorite from the Gallinas Mountains. Four types of deposits are found in the Gallinas Mountains: epithermal REE-F veins, Cu-REE-F veins, REE-F breccia pipes and iron skarn deposits; all are associated with Tertiary alkaline to alkalic-calcic igneous rocks. Alteration includes brecciation, silicification, chloritization, and fenitization. District zonation is defined by Cu-REE-F (±Pb, Zn, Ag) veins that form center of the district, surrounded by REE-F veins. Carbonatites are inferred at depth by the presence of fenitization, carbonatization of the breccias, presence of REE and similarity of the intrusive rocks and mineralization to areas with known carbonatites.

May 1, 2011

By Patrick F. R. Murphy

The mechanization of platinum group metal (PGM) underground reef mining in South Africa has posed a challenge to mining engineers for several decades. This is primarily due to the shallow dip angles and narrow thickness (<1.1m) of the tabular orebodies mined, and the issues faced in developing reliable drilling, bolting and loading machines suitable for such hard-rock mining applications. Presently, mining is typically conducted using hand drills and scraper shovels. These methods, however, are intensive in terms of manual labor, and limited in terms of productivity, and improved methods are desired. This paper will review the technical features of a 4 tonne, low-profile, LHD for narrow-reef PGM mining, developed by EJC Loaders Division.

May 1, 2003

By J. Coffin, R. Multani, C. Deredin

Glencore’s Strathcona Mill has recently evaluated a pyrrhotite depressant combination of diethylenetriamine (DETA) and sodium metabisulfite (SMBS) to improve its overall plant pyrrhotite- pentlandite (Po-Pn) selectivity, with the aim of producing a higher quality nickel concentrate. In a previous paper, key findings from a comprehensive lab-scale program (completed at the XPS Centre) were summarized where, of the depressants tested, DETA/SMBS combination was found to be the most effective in improving the Po-Pn selectivity. The present paper describes the metallurgical program recently completed at Strathcona Mill; DETA/SMBS evaluation on select plant “grab” samples as well as the major results of three DETA/SMBS plant trials conducted on several plant ore feeds (long-term testing). Interestingly, it was found that there was variable success in using DETA/SMBS depressants on the different plant ore feeds; DETA/SMBS (dosage: 25/50 g/t milled feed) on lower Cu feeds demonstrated a ~2% Ni recovery increase at the same Ni grade. On the other hand, higher Cu feeds demonstrated virtually no benefit from DETA/SMBS at the same plant dosage, suggesting that higher DETA/SMBS dosage (at specific locations) than that tested is required to overcome the increased Cu-DETA complexation for these particular feeds. Glencore Nickel – Sudbury Integrated Nickel Operations owns and operates Strathcona Mill which has been processing Ni-Cu ores from the Sudbury Basin since 1968. The valuable sulfides are pentlandite (Pn) – (Ni,Fe)9S8 and chalcopyrite (Cp) – CuFeS2, majority of the sulfide gangue is pyrrhotite (Po) – Fe(1-x)S [0 < x ≤ 0.125] which is present in two forms: hexagonal Po (Fe9S10) and monoclinic Po (Fe7S8) (Multani & Waters, 2017; Lawson et al., 2014). Currently Strathcona Mill processes ore mined from two primary sources from the Sudbury area and produces two concentrate streams: (1) nickel-copper concentrate that is sent to the Sudbury Smelter; and (2) copper concentrate that is shipped to the Fonderie Horne (Glencore Copper, Rouyn-Noranda).

Jan 1, 2019

By J. R. Hart, V. C. Smith, V. P. Babarovich-Hansen, J. H. Schubert

"An introduction and case study of Mintek's latest generation of Milling Circuit controller, the MillStarTM with IES (Interpreting Expert System) is presented. This paper also describes as a case study its installation on a Southern African base metals concentrator plant which has demonstrated improved operation, greatly reduced variation in product quality, as well as increased capacity and availability of the circuit.In this case study, the MillStarTMw as installed along with several other enhancements, including hydrocyclone underflow monitoring, product particle size estimation and flotation circuit stabilisation. MillStarTM utilised the particle size measurement to control grind to within 2% of setpoint, all the while ensuring sump level control, density control as well as mill power optimisation. Mintek' s expertise in the modelling of tumbling mills allowed the development of a specialised optimising controller that ensured the mill was kept in the most efficient operating region.MillStarTM augments the automatic control with useful user interface features, such as on-line trends of any logged variables, historic data warehousing and retrieval and production summary reports.A novel feature that distinguishes the MillStarTMi s the IES (Interpreting Expert System). This is a feature of the software that works with the automatic control code to generate explanations for control actions made by the controller. Often complex control systems are mysterious in nature, reducing trust and eventually resulting in them being switched off. The IES method of exposing the heart of the controller has proved popular and is seen to have potential as a training tool. 314"

Jan 1, 2000

By O. P. Garg

"The Iron Ore Company of Canada (IOC) operations in Labrador and Quebec, in Canada, is among the largest openpit mining complexes on a world wide basis. Since the 1981-82 recession, IOC has embarked on a comprehensive cost reduction and productivity improvement program in order to survive in the world iron ore market.This paper will outline the approach used in prioritizing the cost reduction items.IntroductionMuch of the mining industry in North America is in a crisis state. Most producers are operating at production levels well below capacity, some have been merged or sold, while others have been mothballed or closed permanently. For many of us still operating, the future is uncertain. Despite the many cutbacks and closures, there is still an abundant supply of minerals in the world market and there is almost no hope for any relief on price pressures on most mineral commodities in the near future. The Iron Ore Company of Canada (IOC) operates an iron ore mine, a concentrator and a pellet plant known as the Carol Project located in Labrador City, Newfoundland. This concentrator and the pellet plant have the annual capacity to produce 20 million and 10 million tons respectively. A company owned and operated railway links this operation with the dock terminal facilities in Sept-Iles, Quebec.In the past decade the Iron Ore Company of Canada has been one of the largest producers of iron ore products in the world. Its pellets and concentrates as well as natural ores were sold in North America, Europe and the Far East. In 1981-82, sales, particularly in North America, went into a serious decline. For almost 30 years, the gospel IOC preached to employees was ""production, production!"" There were many innovations, and millions of dollars were spent on the biggest and best equipment, on research and development, on training and developing employees."

Jan 1, 1987

By R. L. Bruening, J. B. Dale, N. E. Izatt, S. R. Izatt

IBC Advanced Technologies&apos; Molecular Recognition Technology (MRT) SuperLig® products selectively and rapidly bind with target metal ions to remove them from solution. The MRT process can produce a high purity separation product of maximum added value at low cost. This paper discusses applications for MRT in the gold industry, including recovery of gold and silver as well as metal contaminants from various process and recycle streams.

Jan 1, 2011

By Jan E. Nesset, James A. Finch, Wei Zhang

"Bubbles are unquestionably the heart of the flotation process. Their size and combined surface area are largely what drive the recovery process. This suggests that plant engineers should be aware of where their plants are operating with respect to what is achievable for these key parameters. The paper presents a model of how the key operating variables of frother type and concentration, gas rate, altitude (above sea level) and viscosity affect the Sauter mean bubble size (D32) and bubble surface area flux (Sb). The results are compared to a set of plant measurements that demonstrate the benchmarking capability of the approach. A case study is used to link hydrodynamic change to improved metallurgical performance.INTRODUCTION At the beginning of the 20th Century the early practitioners of flotation were aware of the importance of understanding bubble behaviour (Rickard, 1916) but measurement of individual bubble and gas behaviour in the industrial environment was not possible due to a lack of adequate sensors. This situation was not rectified until three quarters of a century later with the advent of industrially-robust sensors developed, notably, at the University of Queensland’s Julius Kruttschnitt Mineral Research Centre (JKMRC) (Schwarz & Alexander, 2006) and McGill University (Gomez & Finch, 2002). What emerged was not the chaotic environment perhaps expected, but defined relationships between gas rate, gas holdup, bubble size and the total surface area of bubbles. These relationships could be defined by mathematical expressions and predicted from an understanding of the key process variables (Gorain, Franzidis & Manlapig, 1997; 1999) (Hernandez-Aguilar, Gomez & Finch, 2002) (Gomez, Cortes-Lopez & Finch, 2003) (Nesset, Gomez & Finch, 2007). The early JKMRC work focused on a large pilot cell (3 m3) installed in plant environments, while the McGill work was initiated on flotation columns (Finch & Dobby, 1990) (Xu, Finch & Uribe-Sales, 1991) and later adapted to industrial mechanical cells (Cooper, Scott, Dahlke, Finch & Gomez, 2004) (Dahlke, Gomez & Finch, 2005) (Nesset, Gomez, Finch, Hernandez-Aguilar & Difeo, 2005). Yianatos of Santa Maria University (Chile), a graduate of the McGill research team, carried the work to industrial settings in South and Central America (Yianatos, Bergh, Condori & Aguilera, 2001). The methods of gas dispersion measurement are now well accepted and most major research centres and flotation cell manufacturers have adopted the technology (Pyecha, Sim, Lacouture, Hope & Stradling, 2006) (Yañez et al., 2009) (Collins, Schwarz & Alexander, 2009)."

Jan 1, 2012

Leadership "Organizing a group of people to achieve a common goal" Paradigms ? Rush to produce or cut costs. ? The most important thing after safety is production. ? We?ll take care of ??this?? once in production. ? I know what to do, 30 years of experience in mining. ? I want a 100% reliable operation.

Aug 1, 2013

By D. Komljenovic, J. Paraszczak

"This paper presents the use of queuing theory in truck fleet sizing in open pit mining operations. In the first part, a methodology is developed by which an optimal ratio between the size of shovels and trucks may be determined. The second part gives the fundamentals of the queuing theory and its application in analyzing shovel and trucks. The stochastic character of involved times (loading, truck cycle, etc.) is taken into consideration. Using the above theory, the optimal truck fleet size in actual conditions may be estimated. Minimal operating cost of the working system (shovelstrucks) represents the basic requirement of the analyzed process. The methodology was validated on Caterpillar front-shovel – truck combinations. IntroductionLes camions représentent probablement les équipements les plus utilisés pour le transport dans les mines. Le coût de transport peut parfois atteindre 50 % du coût d’exploitation et 25 % du coût total (Collins, 1996; Kennedy, 1990). Il est critique pour une opération minière de le minimiser. C’est un sujet qui a été traité relativement souvent dans la littérature spécialisée. Les premières applications informatiques dans l’industrie minière ont été développées pour la détermination du temps de cycle des camions.Au fil des ans, la capacité des camions a augmenté et, aujourd’hui, les plus gros manufacturiers de camions (Caterpillar, Orenstein & Koppel, Euclid, Terex, Unit Rig, Komatsu, Liebherr, Belaz) fabriquent des camions ayant une capacité de 200 t et plus dont quelques-uns d’une capacité supérieure à 320 t. Pour les plus gros camions, le coût d’opération peut même dépasser 240 $US/heure dans des conditions modérées (Caterpillar, 1999). Les mines modernes de grande taille peuvent posséder plusieurs dizaines de camions dans leur flotte."

Jan 1, 2004

By D. Komljenovic

This paper presents the use of queuing theory in truck fleet sizing in open pit mining operations. In the first part, a methodology is developed by which an optimal ratio between the size of shovels and trucks may be determined. The second part gives the fundamentals of the queuing theory and its application in analyzing shovel and trucks. The stochastic character of involved times (loading, truck cycle, etc.) is taken into consideration. Using the above theory, the optimal truck fleet size in actual conditions may be estimated. Minimal operating cost of the working system (shovels-trucks) represents the basic requirement of the analyzed process. The methodology was validated on Caterpillar front-shovel ? truck combinations.

Sep 1, 2004