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By G. F. Trainor

At the Canadian Natural Resources Limited (CNRL) Horizon Mine they use Wenco International Mining Systems Ltd (Wenco) Fleet Management System to monitor and control their production fleet with the goal of increasing operator productivity and safety, and raising dispatcher awareness and control. Amongst the broad productivity goals CNRL wanted to achieve with help from the system was a very specific need to blend ore at the truck level. CNRL uses 25m x 25m block geological model information to represent their complex ore body. Wenco's High Precision GPS application, BenchManager provides precise graphical actual-vs-design operator feedback and system integration. Together the two companies advanced the BenchManager product to meet CNRL's needs by using live camera feeds to compare activity with data collection that ultimately lead to changes in the algorithm to include enhanced GPS indicators and the support of a GLONASS assisted solution generating distance and bearing information.

May 1, 2011

By Lindsay A. Robertson

The long term management of acid generating tailings at mine closure is a common issue, however, management of ARD is significantly impacted by local conditions, including climate. Acid generating tailings, over time, will produce acid rock drainage (ARD) if left exposed to water and air, which both contribute to the sulphide oxidation process. The long term closure of tailings storage areas is a concern from both environmental and engineering perspectives, with long term acid generation and dam stability the main risks. Several approaches can be taken to minimize ARD from tailings facilities using cover systems. Three tailings facility cover case histories, in areas of net positive water balances, were investigated using unsaturated flow modelling software to determine the long term potential for limiting ARD by increasing saturation of the tailings and decreasing oxygen ingress. Each case study demonstrates the importance of integrating the tailings dam engineering into tailings cover closure design. Model predictions are compared to measured saturation levels to assess the accuracy of the calculations.

May 1, 2011

By Trung Nguyen

Midwest is a unique uranium deposit with exceptionally high arsenic content. The ore body is located 17km west of the McClean Lake operation. The McClean Lake mill will be modified to process Midwest ore and handle solid wastes coming from the Midwest water treatment plant. This paper describes the modifications required of the McClean Lake mill, process challenges associated with treatment of the arsenic, and the possibility of recovering nickel and cobalt as a by-product. It also reviews the complexity in the design of the Midwest water treatment facility which incorporates reverse osmosis technology with conventional physical-chemical water treatment.

Aug 1, 2010

By Theophile Yameogo

Much has been said about the methodology of geomechanical design in underground excavations. However, the geological, hydrogeological and geotechnical complexities encountered at the production horizons in the Athabasca Basin commanded for a novel approach in the geomechanical assessment and design of underground openings. Rock mechanics engineers at Cameco McArthur River have been able to establish a practical methodology that goes beyond known conceptual approaches. In this paper, the author describes the original challenges and unique approach in the geomechanical assessment for drifts and chambers development. The example of the successful development of the 510-8225N Chamber will also be presented.

Aug 1, 2010

By B. S. Riess

A novel design for an automated uranium pellet stacking system is presented. This system is designed as a drop-in solution to the current production line to enhance the fuel pellet stacking process. The three main goals of this system are to reduce worker exposure to radiation to as low as reasonable achievable (ALARA), improve product quality, and increase productivity. The proposed system will reduce the potential for human error. This single automated system will replace the two existing pellet stacking stations while increasing the total output, eliminating pellet stacking as a bottleneck in the fuel bundle assembly process.

Aug 1, 2010

By Steve Simard

Suite aux excellents résultats, obtenus avec la technologie des détonateurs électroniques dans des chantiers longs trous de grandes dimensions, nous avons décidé d?étendre cette technologie dans les ouvertures, dans le dynamitage de piliers et dans différents chantiers complexes. Cette technologie nous a permis d?effectuer l?abatage de chantiers avec un très grand nombre de trous sans détériorer le terrain. L?équation est bien simple avec les détonateurs électroniques, plus gros sont les dynamitages moins de fois les épontes se font ébranler, moins de blocs d?effondrement se retrouvent dans les points de soutirages entre les dynamitages et plus la fragmentation est meilleure. La flexibilité d?opération que nous avons obtenu avec les détonateurs électroniques est difficilement quantifiable, mais elle nous a permis de maintenir notre rythme de production mensuelle même avec certains chantiers complexes. Il est bien certain que l?utilisation des détonateurs conventionnels a encore sa place dans une mine conventionnelle comme Beaufor, mais l?utilisation des détonateurs électroniques a aussi sa place dans certaines situations spéciales. Pour terminer, bien que la technologie des détonateurs électroniques soit encore dispendieuse, nous pensons encore l?utiliser pour optimiser certains dynamitages et ainsi maintenir notre flexibilité d?opération.

Oct 1, 2004

By H. W. Hughes

"The Wasamac Gold Mines mill, situated 10 miles from Rouyn-Noranda on highway 59, commenced milling April 1st 1965 at a rate of 700 tons per day. This has gradually increased to over 1200 tons per day in December. The mill has done up to 1400 tons on occasion.The ore was formed in the Wasa shear zone by means of replacement. The minerals which replaced the original rocks were carbonates, quartz, pyrite, chlorite, gold and silver. Work index varies from 9. 6 on the chlorite to 11. 6 on the quartz. The gold is very finely disseminated throughout the gangue and while associated with the pyrite is not included in the pyrite. Very seldom is gold found or seen in the free state.Test work showed a medium fine grind of 85 to 90 per cent was necessary to achieve a 95.00 per cent extraction. Straight cyanidation time of 30 to 36 hours was indicated. This has been borne out by subsequent mill performance with a grind around 87 per cent minus 200 mesh and extraction ranging from 95 to 96 per cent.When it was decided to bring the Wasamac property into production, the Bicroft Uranium Mines Ltd. crushing and grinding units together with one pebble mill and the pachuca tanks from Dyno Uranium Mines Ltd. were purchased.Wasamac crusher house and mill buildings are of laminated wood construction, covered with 5/ 8th inch plywood and corrugated iron sheeting."

Jan 1, 1966

By J. Kicki

The paper depicts the current status of the EKSPERT mining machinery management system and shows the prospects for its further development. The system is the result of a rare attempt to utilize the comprehensive dataset; this refers to a precisely identified group of users and is used to develop a solution with a scope that encompasses other areas of activity within the company. The authors present the incredible flexibility and usefulness of the system used at KGHM Polska Miedz S.A. for everyday control of the mining machinery fleet. The issue of visual aspects of the reports generated by the system is handled separately and used as a tool allowing for implementation of the methodological assumptions of EKSPERT. A concept for creating a system for assisting decision making in the process of mine management with the use of IT tools and production monitoring is also discussed. The solution is based on integration of information from both the monitoring field and visualization of the technological process around the Production Reporting Center.

Aug 1, 2013

By Peter A. Witt

Highland Valley Copper is a conventional truck-shovel mining and flotation concentrator operation located some 75 kilometres southwest of Kamloops, B.C. (Figure 1). The ore is located within a porphyry copper deposit and is mined at a rate of 135,000 metric tonnes per day from two separate open pits. The nearby mill produces concentrates containing 375 million pounds of copper and 5 million pounds of molybdenum metal yearly. In the Valley pit, head grades are roughly 0.40% Cu at a 0.23% Cu equivalent cut-off. The Valley pit strip ratio currently sits at 0.55:1 with waste quantities made up of separate rock and unconsolidated overburden units. From the mill, concentrates are trucked to nearby Ashcroft and then hauled by rail to ocean port facilities in Vancouver. The mine employs 950 persons and is planned to operate until 2009. The operation is a partnership between TeckCominco with a 63.9% interest, BHP Billiton holding 33.6%, and others 2.5%. Management is shared by the two principal owners and directed by a management committee.

May 1, 2003

By D. Lemieux

A gold bearing pyrite concentrate was treated at the pilot scale for the extraction of gold. Mineralogical analysis of the concentrate identified gold to be mainly present in the form of a solid solution in pyrite. This gold distribution resulted in a poor extraction yield of 55% by direct cyanidation. A piloting campaign including an oxidative pre-treatment by roasting in a fluid bed was followed by treatment with halogens for gold extraction has led to a gold extraction yield of 96.5%. Sulphur removal during the oxidation was very efficient at >99.5% and gold extraction by the halogens was completed within a 1 hour contact time. The piloting was performed on a 300 kg sample and uses a diluted solution of hypohalites as the oxidizing agent for gold extraction. Sulphuric acid was injected in the reactor during the halogens treatment to lower pH to 2. The diluted solution of hypohalites (1-3%) was generated by electrolysis during the piloting campaign in a membrane-less electrolysis cell. The extracted gold was recovered over activated carbon in column and the gold depleted brine was treated for impurities removal and recycled for further gold extraction. With the recycling of water and brine, the regeneration of hypohalites and with a barren solid that is inert and stable, the Nichromet Extraction technology is a green process where the protection of the environment does not preclude profitability.

Aug 1, 2013

By Rebecca L. Jones

The paper addresses the application of XPAC AutoScheduler at the Fort Hills Energy Oil Sands Project to complete fast turn around ?what if? scenario testing of different mine schedules. Traditional scheduling approaches involve engineers making a ?best guess? at the required mining sequence, loading this sequence into a scheduling package and testing the results to determine if the schedule meets corporate objectives. This process is iterative and can be very time consuming. Autoscheduling techniques, on the other hand, are based on the engineer pre defining the mining rules and constraints of the deposit. The software then automatically selects a sequence of mining which the schedule should try and achieve, based off specified corporate objectives. Under this system the engineer is able to adjust the objectives and rules to evaluate numerous scheduling scenarios quickly and easily. An XPAC AutoScheduler model was built, documented, and implemented by Runge and Petro-Canada Oil Sands Inc. personnel in a month. It is currently being used by Petro-Canada Oil Sands Inc. to run multiple schedule scenarios, most taking less than ten minutes configure and ten minutes to schedule. The results of each schedule are tabulated with supporting graphs on; the bitumen grade profile, strip ratio, ore inventories and mined tonnage. In addition to this, the block model may be animated to show the progression of the resources mining the schedules.

May 1, 2008

The Boleo project is located in Mexico close to the town of Santa Rosalia on the Baja Peninsula. The Boleo deposit contains copper, cobalt, zinc and manganese values as oxides with minor sulfides. The Boleo deposit is metallurgically challenging due to: 1) the requirement to recover four separate metals; 2) the presence of high levels of clay in the deposit resulting in difficult solid-liquid separations, and; 3) the need to use seawater for the bulk of the processing. Baja Mining, Bateman Engineering and SGS Lakefield Research have collaborated to develop and test a process flowsheet to recover copper, cobalt, zinc and manganese products at Boleo. The key steps in the flowsheet are: ? Feed preparation (scrubbing and ball milling of oversize) in copper raffinate ? Ore leaching using oxidative and reductive leaching ? CCD washing using high rate thickening technology ? Copper SXlEW ? Treatment of a bleed solution for cobalt, zinc and manganese recovery The process for cobalt, zinc and manganese recovery involves iron and aluminum removal followed by cobalt/zinc bulk extraction using CSIRO's DSX solvent extraction system and selective zinc and cobalt stripping. The zinc strip solution is evaporated to produce zinc sulfate monohydrate crystals to market and cobalt is recovered via a further SXlEW process as high purity metal. Manganese is precipitated as manganese carbonate from the DSX raffinate solution. This paper will review the Boleo process flowsheet and provide detailed results from the 2006 pilot plant operation conducted at SGS Lakefield in Canada.

Jan 1, 2007

By L. Kraszewski

"IntroductionPortland cement is produced by burning an accurately proportioned mixture (raw feed) of finely ground limestone, silica, alumina, and iron oxide. The kiln discharge (clinker) is a chemically complex mixture of calcium silicates, aluminates and ferrites which when ground and blended with from 2 to 5 percent of calcium sulphate is sold as Portland cement.ManufactureThe most common raw materials are limestone and clay or shale. The raw mix is finely ground and heated to about (2600°F) 1430°C to decompose the calcium carbonate and combine the calcium oxide with silica, alumina and iron to form a partly fused clinker. The clinker is then ground, usually with a small proportion of calcium sulphate (gypsum), which regulates set. Cements with special properties are produced by varying the oxide composition and also by adding small amounts of chemical agents at the clinker-grinding stage or later.Clinker is manufactured by either wet or dry process methods. In the wet process, raw materials are prepared, blended and fed to the kiln as a water slurry (about 30-35% water) . In the dry process, raw materials are prepared, blended and fed to the kiln as a dry powder (about 0.5% water). The processing procedure is as follows:"

Jan 1, 1982

By R. Hagiwara, S. Kobayashi, K. Yasuda, T. Nohira, K. Kondo

To establish a process for the electrochemical recovery of rare earth elements from used magnet scraps, the electrochemical formation of RE-Ni alloys in molten NaCl-KCl-RECl3 salt at 973 K was investigated. Cyclic voltammetry and open-circuit potentiometry indicated the formation of several phases of RE-Ni alloys. The formation potential for each RE-Ni alloy phase was determined from the results of scanning electron microscopy and X-ray diffraction of alloy samples prepared by potentiostatic electrolysis of a Ni plate electrode at various potentials. The optimum electrolysis conditions for the separation of Nd, Dy, and Pr are discussed.

Jan 1, 2014

By K. C. Sole

In most copper solvent-extraction operations, an important consideration in choice of extractant is the requirement for high selectivity of copper over iron. Ester-modified aldoxime extractants presently offer the best Cu:Fe selectivity. In some plants, however, the process feed liquors contain significant amounts of manganese but little iron. Although manganese is not chemically extracted by oximes, trace amounts are carried over to the electrowinning circuit by physical entrainment. This may result in anodic oxidation of manganese which, in turn, can cause oxidative degradation of the organic phase when returned to the solvent-extraction circuit in the spent electrolyte. Many of these operations prefer to operate with higher levels of iron reporting to the advance electrolyte, as appropriate control of the Fe(II)/Fe(III) couple will ensure that manganese remains in the benign Mn(II) form. A new reagent, LS 4202, designed by Cytec, now offers the possibility of tailoring the iron co-extraction, so that appropriate Cu:Fe selectivity can be achieved in the solvent-extraction operation to maintain an electrolyte Fe:Mn mass ratio of >10:1, while retaining the other benefits offered by ester-modified aldoximes. The results of an integrated solvent extraction-electrowinning pilot-plant trial are presented, in which the performances of the conventional extractants ACORGA® M.5774 and LIX® 984N are compared with LS 4202. The Cu:Fe selectivity is demonstrated, along with results on the transfer of other impurities to the advance electrolyte.

Jan 1, 2007

By B. Dubreuil

Arsenical bearing deposits are posing an increasing challenge for the mining industry. In particular, mineral processing of arsenical sulfidic ores for base and precious metals recovery tend to produce problematic arsenical tailings. This arsenic being present as sulphide or oxide, tends to dissolve, contaminating surface and underground waters. To meet the environmental regulations, it is often required to stabilize the arsenic in a more insoluble form. Nichromet has developed a new patented technology using vitrification of the arsenic oxide in an economical way, giving a stable solid, well below the environmental regulations upon leaching. This technology involves oxidation of As (III) to As (V), by using a low cost natural oxidizer and transformation of the produced arsenic oxide into calcium arsenate, which is not volatile at the melting temperature of the glass. This technology would be advantageously applied on most cases around the world where sulphide concentrates are oxidized in a fluidized bed or smelted.

Aug 1, 2013

By Marcel Laflamme

Underground mine workers are continuously exposed to many sources of noise and vibration in carrying out their tasks. Even though the vibration and sound level of some mining equipment is documented, it was found that this information is not readily available for many pieces of equipment and that it is not considered when choosing equipment or planning tasks. As well, health problems related to vibration and noise are among the main causes of work-related compensations in mines. Considering those facts and although no Canadian regulations could force employers to limit the exposure of their workers to vibration, the Société de recherche et développement minier (SOREDEM) decided to address the problem by including vibration among their research priorities. In order to characterize noise and vibration sources of different mining equipment used for underground mining, the authors have performed a study in 8 different mines in Québec on 28 different mining equipments. The paper will present the procedure that was followed to select the list of equipment to be evaluated and the low cost acquisition system developed to perform multichannel time domain acquisition in harsh environments. It will also present the results obtained for the noise level produced by the equipment as well as for the hand-arm and whole-body vibration exposures.

Aug 1, 2013

By J. Seidel

In 2009 Newmont Mining Corporation’s annual global spend on grinding media reached $94M USD, having doubled in the five years since 2004. The major contributing factor to the spend escalation during this period was unit consumable price, with total media consumption also rising as a function of annual ore tonnes milled. In an effort to better understand and manage the growth of this expenditure a significant supply chain management program was implemented. This was complemented by a series of technical initiatives focussed on grinding media specifications, quality management and the prediction of grinding media wear rate as a function of physical ore characteristics. This paper discusses the methodology and outcomes of these activities.

Jan 1, 2012

By L. Torres, C. S. R. Rondestvedt, M. Bustos

In February 2010, Teck’s newest Concentrator at Mina Carmen de Andacollo (CDA), Andacollo, Chile was commissioned. The Concentrator is a single line configuration, comprising of one 36 ft diameter x 20 ft long SAG mill driven by an 18,000 hp gearless drive. The SAG mill feeds two ball mills each 25 ft in diameter x 40.5 ft long, each driven by a total of 19,000 hp through dual pinion drives. A series of four phases will be reviewed from operational readiness, mechanical completion, commissioning, and ramp-up. Also, now after 6 months of operation, this paper will review the significant steps taken during ramp-up enabling the announcement of commercial production, in October 2010.

Jan 1, 2012

By Theophile Yameogo

The rock mechanics literature has documented the challenges, failures and successes of tunneling through weak rocks. Cases usually deal with low RMR rock masses or high stresses in a fractured zone. With the combination of 5MPa water pressure, 14 RMR ground with clay infillings and ground freeze walls, the case of the 510-8225N development drift at McArthur River is certainly much more challenging, especially when high grade uranium production is at stake. The article explains the excavation and the ground control techniques that were used to overcome the challenges of development at the Unconformity in the Athabasca Basin.

Aug 1, 2010