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By P. Hansman

"Place Dome Canada's Detour Lake Mine is a low-grade gold producer located in northeastern Ontario. Production is targeted for 2850 tonnes of ore per day. As reserves and mining areas continued to be found below and far to the west of the shaft (Fig. 1), it became necessary to review and upgrade the materials handling facilities. This paper deals with the selection, design and construction of an underground crusher and conveyor system capable of handling up to 450 tonnes per hour from the lowest existing level in the mine.BackgroundThe Detour Lake mine site is accessed via secondary Highway 652 which runs northeast out of Cochrane, Ontario. The road consists of 200 Ian of hard top followed by 100 Ian of well maintained gravel to the mine site. A 1500 m airstrip is maintained at the mine site for emergency use. Prior to 1991, the workforce was flown to and from the mine site. Crews were now bused to the site from Timmins. Remnants of a winter road exist to the southeast which at one time ended in La Sarre, Quebec. This was the route used to haul bulk items during the construction period and early production years.A town site has not been established at the site for the current operations. Instead, a rotational scheme is being utilized whereby most personnel will work seven days on site followed by seven days off site. For some employees, however, the work week is termed as a four/three schedule where they work 42 hours between Monday at 10:00 a.m. and Thursday at 4:00 p.m. with the following three days off. All surface employees and maintenance employees underground work 12-hour shifts. All underground employees work a lOV2-hour shift. Supervisors work a similar schedule as their crews, however, other staff may overlap their rotation during the week.A five-compartment shaft was sunk in 1984 from surface to the 610 m elevation. Shaft stations were established at the 120 m, 260 m, 360 m, 460 m, and 560 m levels. The cage compartment consists of a single deck, 4O-man cage in balance with a counterweight. The cage hoist is an Ingersoll-Rand 10H and is regulated to travel at 4.1 m/s. Two 9 t skips operate in balance at a travel speed of 7.1 mls. The skip hoist is a 3.05 m drum Nordberg. Both hoists are automated to function without a hoistman during normal skipping and cage service runs."

Jan 1, 1995

By ANNE FUZESY

Soluble potassium salts in bedded underground salt deposits supply most of The world demand for potassium f or agricultural and industrial use. The potassium salts, sylvite and carnallite, were f irs, noted in drillcores in southern Saskatchewan during The search for oil and gas in ihe early /940s. Problems in shafi sinking beset pioneering potash companies, however, and cominuous production did no, begin uniil 1962. Powsh deposits in southern Saskatchewan occur within ihe uppermost 60 111 of the Middle Devonian Prairie Evaporite a, depths in excess of 900 m. Four groups of po/ash-bearing haliie beds have been distinguished: the Esierha-::,y, White Bear, Belle Plaine and Paiience Lake members. Powsh deposiis extend a jell' kilomeires into Manitoba and south imo orth Dakoia and non heasiern Moniana. Individual potash-rich beds are extensive and consistent in grade and Th ickness. Local th ickening occurs where carnallite is the dominani poiash mineral. Th e preferred ore, sy lviniie, is a clean mixiure of sylvite and haliie. Carnalliie and insolubles are avoided wherever possible because of Their detrimenwl effects on mine stability, grade and refining. Sy lvin ite is exTracted by underground mining or brought TO swjace as brine in solution mining. Poiash is separaiedfrom halite byfloiation or sequential crystallization. The refined produci, potassium chloride, is employed as a fertilizer ingredient as well as in chemical and other industrial capaciiies. The ten poiash mines of Wesiern Canada all are in Saskatchewan and account for aboui 25 per cem of world production. Faciliiies are being expanded, and a new mine and refinery was planned for ihe Breden bury area. Deposiis in Manitoba also were being evaluaied.

Jan 1, 1984

By Wei Sun, Xiangsong Meng, Xiaodong Li, Weisheng Huang, Yuehua Hu, Chonggao Cao, Haisheng Han, Wensheng Chen, Runqing Liu, Central South University

"The similar flotability of scheelite, fluorite, and calcite resulted in the difficult separation by flotation. This work revealed the effect of water glass on the flotation of scheelite by FTIR and the wettability change of the usual cleavage plane, and proved that water glass inevitably influenced the flotation of tungsten minerals to a large extend in traditional fatty acid flotation process. A new collector, benzohydroxamic acid complexes, was found to be selective for the separation of scheelite and calcium minerals with little water glass. Hence a novel flotation process was developed for the recovery of tungsten minerals in shizhuyuan mine in China. Normal temperature flotation of tungsten minerals was developed to instead of the classical “Petrov's process” for scheelite-calcite-fluorite type ores. Compared with the traditional process, the recovery was improved by 10% and the grade of scheelite concentrate was above 55%. The disappearance or decreasing of water glass contributed to improving the recovery of tungsten and fluorite and the circulation of water and reagents.INTRODUCTIONChina is rich in tungsten resources and the proved reserves accounted for 60% of the world's reserves (Cai Gaipin et al., 2009). However the wolframite has been dried up and the scheelite resource has become the main resource of the tungsten metal. Scheelite deposits were classified to scheelite-silicate type and scheelite-calcite-fluorite type based on the associated gangue minerals. Scheelite was easy to separate from the silicate minerals. Flotation separation of scheelite from calcium minerals creates difficulties because of the existence of the same cation in the minerals and similar physicochemical characteristics such as solubility, hardness, specific gravity, PZC (point of zero charge) etc.(Arnold & Warren, 1974; Yongxin & Changgen, 1983; Ozcan & Bulutcu, 1993a; Deng et al., 2015, 2016;). The conventional collectors used in the flotation of scheelite ores are generally fatty acids or fatty acid derivatives ( Yongxin & Changgen, 1983; Oliveira & Sampaio, 1988; Sivamohan, 1988; Shi et al., 2014; Bo et al., 2015). It is difficult to separate scheelite especially from calcite with these reagents because the adsorption mechanism of these collectors occurs through chemisorption of the oleate ion onto the mineral surface (Atademir et al., 1979; Changgen and Yongxin, 1983; Hiçyìlmaz et al., 1993; Hu et al., 2011). Therefore, it is almost impossible to separate them by fatty acid flotation without using any selective depressant. Although oleoyl sarcosine was used as a selective collector in the flotation of fluorite and siliceous scheelite ores (Ozcan & Bulutcu, 1993b; Ozcan et al., 1994), this selectivity is not adequate for a low-grade calcitic scheelite ore. Unfortunately, the reagents such as organic colloids (dextrine, starch), quebracho, sodium phosphates, sodium silicate solutions containing polyvalent cations (hydrosols), etc. (Yongxin and Changgen, 1983; Schubert et al., 1990; Shi et al., 2014; Bo et al., 2015) used for calcite depression also depress scheelite to a large extent."

Jan 1, 2016

By Adrian Dance

The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copper-zinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products. Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance. Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of the ROM and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling. One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost and reagent consumption. Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ?equivalent?) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ?ore? becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance ? and thereby profitability ? is a powerful tool. In an operation such as Antamina, where managing ore sources, campaigns and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency.

May 1, 2003

By R. M. Graves, C. B. McKenzie, D. Barbour, D. W. Desnoyers

"Abstract -The prospective Tulks volcanic belt hosts five significant massive sulfide deposits, Tulks Prospect, Tulks East, Jack's Pond, Daniel's Pond and Victoria Mine, as well as numerous showings and indications throughout its 70 km outcrop length. Regionally, the 498 Ma sequence consists dominantly of felsic pyroclastic rocks and flows with interbedded mafic volcanic units and fine­ grained sediments, commonly graphitic. Contemporaneous granitoid rocks occur in the south half of the belt. Rocks usually display a strong NE-SW, steeply dipping, penetrative foliation and other shear-related high-strain fabrics. Facing directions are normally northwest, although there is local evidence of folding. Sulfide bodies and their alteration systems are deformed and shape-modified in the style of ambient strain.The Tulks, Tulks East and Jack's Pond prospects appear to occupy a similar stratigraphic level, on or near the contact between a thick felsic pile and an overlying broad, conductive package of graphitic sedimentary rocks. AU are pyritic deposits with well-developed footwall alteration systems. The Tulks prospect comprises four polymetallic lenses totalling 750 000 t. Three lenses constituting more than 6 000 000 t of sulfide mineralization are indicated at Tulks East but only the 210 000 t ""B"" lens contains significant base metals. Jack's Pond consists of a very extensive, zoned alteration complex in which four lenses of massive to semi-rnassive pyrite + chalcopyrite are known.The central part of the system, characterized by Mg chlorite and carbonate, is enveloped by pervasive sericitization and capped by intensely silicified and pyritized volcanics. The sulfide lenses are interpreted as part of the footwall zone and are beneath that part of the system most likely to host polymetallic massive sulfides.Daniel's Pond differs from the other prospects in such fundamental ways as metal content, associated alteration and structural setting. The deposit comprises strongly tectonized, Ag-rich, Zn-Pb mineralization distinguished by a pronounced Ba-As-Sb signature. Mineralization is confined to a narrow, north-south high-strain zone which separates unstrained mafic volcanic rocks to the east from well-foliated felsic rocks. The deposit Jacks an extensive alteration halo and at its north end is associated with a lens of barren, undeformed massive pyrite.The Victoria Mine deposit, the most cupriferous of the five, is related to a moderately dipping structure that separates well-foliated Tulks volcanic rocks from an overlying, Jess deformed volcanic­ sedimentary sequence that may be as young as 462 Ma. The structure is also the locus of black chlorite, dolomite and quartz alteration. Structurally remobilized precursor sulfide mineralization is one possible source for the deposit."

Jan 1, 1993

By K-A. Adamson

If fuel cells and hydrogen are to become a mass market reality a substantial amount of further research and development needs to be undertaken. Work in hydrogen storage, production, the economics of all aspects of fuel cells and hydrogen, materials balances, and product integration are just a few of the areas that are under focus. Setting R&D targets, and providing R&D funding are therefore areas that are central to the long term development of the market, and areas in which a number of governments worldwide are highly active. Some governments, such as Japan and Korea, have set a number of very ambitious, highly focused, long term targets and are backing this up with substantial funding, others such as the EU are working on a more integrated approach, wrapping some fairly fundamental R&D into large integrated projects which run in combination with a number of other market aspects, such as public acceptance and roadmapping. The US is slightly different, in that although is has a number of long term programmes and targets, FreedomCar and SuperGen being just two, the levels of funding are set annually with the passing of each years Fiscal Budget. This paper takes three high profile regions and analyses the R&D targets and funding levels for fuel cells and hydrogen. Criteria that will be looked at include: Time frame of target(s), level of ambition, funding issues, including: Funding windows, levels available, funding barriers, overall programme goals. The added value to this paper is that it will provide a clearer picture of where each region is heading, what are its strengths and weaknesses, in terms of R&D and where there may be areas for potential international collaboration.

Jan 1, 2005

By Laxman M. Amaratunga, Glen G. Hein

"Most mining operations utilize the tailings coarse fraction for backfilling while the fines have been traditionally disposed on surface in tailings ponds. Recently, paste fill has been developed which uses a fraction of the fine tailings (10-30% w/w of <45 µm) in the fill (Brummer and Moss, 1991). This development allows a mining company to use a portion of the fines for backfill, but still requires surface impoundment of the unused tailings. Reactive tailings have the added problem of generating acid after being oxidized in the presence of air and water. Treating acid mine drainage (AMO) from these ponds has proven to be a costly environmental problem and a long term liability.One practical method to reduce the environmental impacts associated with the tailings pond is to modify the physical and chemical prope1ties of the fine tailings so that they can be utilized in an environmentally safe manner. This was accomplished by agglomerating the tailings into pellets and using theses pellets as a coarse aggregate in a total tailings paste fill. This technology does not require any supplemental sand or gravel to be added to the fill.This paper presents the ongoing research into utilizing these tailings agglomerates as a coarse aggregate fraction, in order to create a total tailings paste fill which has supe1ior strength characteristics.IntroductionThe Canadian mining industry produces more than 500 million tonnes of tailings and waste rock annually. The waste rock is usually returned underground for use as rock fill in underground support with the tailings remaining to be disposed of in tailings ponds. Tailings consist of a coarse and fine fraction, and can be either reactive (acid generating) or non-reactive. In an effort to minimize tailings disposal, the coarse fraction has been used underground in backfill along with alluvial sands. This diversion of the coarse fraction, however still requires that the fine fraction be disposed of in tailings ponds. This disposal creates the potential for acid mine drainage (AMO), since in the presence of air and water, reactive sulphide tailings can generate acid. It is therefore an important goal in the mining industry to minimize the disposal of fine tailings into tailings ponds since the treatment of AMO is a costly and long-te1m environmental liability."

Jan 1, 1997

By Tadeusz W. Wlodek

THE known phenomenon that a test-piece of ferro-magnetic steel is magnetic after it has been broken in tension indicates that, while it is being loaded, the steel acquires magnetic properties. In the present investigation of the influence of the stress on the magnetic flux, repeated pulsating stresses of increasing amplitude, varying from zero to the maximum tensile value, i.e., pull-pull loading, were employed. The specimens were prepared from two types of carbon steel and two of alloy steel. The magnitude of the magnetic flux was determined indirectly. The voltage and mode of variation of the electromotive force induced in a coil surrounding the stressed steel specimen were measured as an indication of the varying magnetic flux within the specimen. Curves representing the electromotive force induced by the varying magnetic flux show that as the tensile load increased so also the magnetic flux increased, with a corresponding increase in measured e.m.f. At a certain stress there is a sharp bend in the voltage curve (point Win the diagram, Figure 5); this critical stress corresponds very closely with the yield stress (0.2 per cent permanent strain). Beyond this point, slight increases in the stress produce large increases in the voltage. The wave form of the e.m.f. was registered on an oscillograph. Analysis of the curves so obtained demonstrated the necessity of continuing these experiments, in order to determine the type of induced wave form associated with various types and amplitudes of stresses. In these experiments, the shape of the stress wave was sinusoidal, although the shape of the induced e.m.f. was sinusoidal only up to a certain load and became more and more complex above this load.

Jan 1, 1944

By W. A. Crosby, W. K. Smith, K. L. McDonald

"IntroductionThis paper describes how the introduction of two blasting techniques and the resuItant development of new dragline digging methods have increased the productivity of single- and double-seam dragline operations at the Rietspruit opencast mine.LocationRietspruit , one of South Africa&apos;s largest opencast strip mines, is situated some 11 5 kilometres east of Johannesburg in the Witbank coal field.BusinessRietspruit is a joint venture between Transvaal Consolidate d Land and Exploration Company (T.C.L.) and Shell, South Africa. Rietspruit is administered and managed by Rand Mines, the Mining division of Barlow Rand, transportation and marketing being the responsibility of Shell. The total saleable coal product, approximately 5,5 million tons per annum, is exported via Richards Bay.Presplitting and Throw BlastingPresplitting was initially introduced in September 1980, as a means of dewatering t he overburden and mid burden to facilitate the use of dry-mix explosives a s opposed to slurry explosives.The utilization of the throw blasting technique arose as a direct result of observed ground movement after the successful introduction of presplitting. The first trials commenced in March 1981 on the double-seam operation. The methods, economics and resulting advantages are fully described elsewhere. A brief description follows.Method of PresplittingAfter determining the desired presplit line, 250-mm holes are drilled to top of coal at 4-m to 6-m intervals, dependent on the competency of the rock overlying the coal. A single 60-kg charge of slurry explosives is located at the bottom of each hole, no tamping is used and all the holes are detonated simultaneously. The results are a competent, straight, vertical highwall. This enables accurate control of the first row of blast holes closest to the highwall, which is a prime requisite for successful throw blasting."

Jan 1, 1983

In most instances, the preferred mining methods in steeply dipping narrow vein deposits are selective methods such as cut and fill or shrinkage. The main advantage of these methods lies in the higher degree of control over dilution that can be achieved. However, where ore body geometry lends itself to it, high yield bulk methods can also be attractive. Higher productivity (and the associated lower costs) and lower worker exposure are some of the significant advantages that have made such methods so popular. The Lapa gold mine located in North-Western Quebec uses the long hole mining method (with cemented rock fill) very successfully despite challenging ground conditions. This paper focuses on the experience of the mine with regards to drilling and blasting practices. Firstly, the reasons that prompted the selection of this mining method at Lapa are examined. Secondly, the challenges that the difficult ground conditions found at Lapa pose to drilling and blasting are discussed. Finally, the results of trials of different drilling and blasting strategies that were performed at the mine are presented with particular emphasis on the lessons learned.

Aug 1, 2013

By D. S. Speakman

The copper-zinc orebody at Sherritt Gordon&apos;s Ruttan Mine occurs in a structurally complex area of the Rusty Lake greenstone belt in northern Manitoba. Problems in interpreting drill results indicated a large deviation, and the structural complexity an erratic deviation, of drill holes. This was confirmed when a surface hole was intersected 420 feet to the left of line on the 800 level. This problem acted as a catalyst in promoting a search for a suitable down-hole survey method. The instruments investigated included magnetic multishot and gyroscopic units as well as the ABEM Reflex-Fotobor. Only the Fotobor came close to meeting the company&apos;s needs of simplicity, reliability, accuracy and ownership. In this paper, the methods of operating this instrument, as well as the data extraction and reduction techniques, are described. Data on the accuracy and repeatability of the instrument are presented, and a tabular presentation of the results of surveying on 86 holes totalling 64,000 feet of drilling is made. Preliminary statements of the results of ongoing research on causes of hole deviation are presented and recommendations for minimizing deviation are given. The use of the survey device is recommended in areas of structural complexity, for very steep or backsight holes and where expected ore intersections are missing.

Jan 1, 1978

By D. W. I. Griffiths, J. C. Bélanger

"La Division Matagami de Minéraux Noranda inc. a profité de la construction de sa nouvelle mine (Isle-Dieu) pour continuer sa modernisation.L&apos;utilisation d&apos;automates programmables (PLC) s&apos;est intensifiée pour contrôler et automatiser de plus en plus d&apos;équipement dans ses minessouterraines, au concentrateur, dans les atelierset bureaux.Tous les PLC comrnuniquent entre eux et les IBM PC sont utilisespour exterioriser l&apos;information et faire Ie lien entre Ie personnel et les automates. Le système Central IBM 36 emmagasine les donnees traitees par lesPLC (a travers les PC). Ces donnees sont transmisesau programme d&apos;entretien de chaque equipement et compile les heures, cycles, tonnes, etc., fait imprimer automatiquement les feuilles d&apos;entretien préventif &apos;, etc.Les principales realisations adate et en progrès pour la mine Isle-Dieu sont:• automation complète du système de remblayage du concentrateur ala mine Isle-Dieu situee a2 km de la mine principale;• automation du fonctionnnement des ventilateurs qui comprendra la position des portes de ventilation, Ie chauffage, Ie débit, etc.;• automation des pompes, surveillance des sous stat ions électriques, concentration des gas (CO, SO2) à chaque niveau en tout temps et du propane à l&apos;entree d&apos;air frais;• tonnage et cycles par Ie treuil; et• contrôle d&apos;autres équipernents à differénts niveaux. D&apos;autres travaux furent egalement effectues par les employes, tels que:• la conversion d&apos;un Scooptram ST5A de diesel à électrique;• I&apos;installation complete de systèmes de depoussierage a I&apos;eau (scrubber) pour le concassage secondaire;• I&apos;installation d&apos;un marteau hydraulique avant les concasseurs coniques;• la rénovation des cellules de flottation ; et• l&apos;installation d&apos;un système de gardiennage par caméra. D&apos;autres projets seront effectués ou étudiés:• automation d&apos;un Scooptram"";• automation d&apos;un marteau hydraulique;• récupération de Scooptrarn; téléguidé:• gestion de l&apos;énergie, contrôle de la demande, surveillance et contrôle de l&apos;équipernent de machines fixes(compresseurs, boulloires, pompes à vide, génératrices, débits et pression d&apos;air, eau pour diagnostiquer les problémes, analyser les coûts;• concasseur portatif pour fabriquer de la pierre concassée pour utiliser dans les chemins sous-terre, et• utilisation de micro-ondes pour transmettre les images captées par camera."

Jan 1, 1990

By L. D. Snyder, J. K. Russell

"The Lower Jurassic Iron Mask batholith intrudes Upper Triassic Nicola Group volcanic rocks in the Quesnellia terrane of southcentral British Columbia and hosts Cu-Au mineralization. The batholith comprises three mappable intrusive phases, including: Pothook gabbro to diorite, Cherry Creek monzodiorite to monzonite and Sugarloaf diorite. The Iron Mask hybrid forms a fourth mappable unit that makes up to 45% of the areal exposure in the batholith. It is highly variable in texture and composition and subdivided into three types; Type I and II have abundant (partially digested) xenoliths, many of which are derived from the Nicola Group, whereas Type III is xenolith-poor and shows extreme outcrop-scale textural diversity.Pothook and Cherry Creek rocks are similar in texture, mineralogy, whole rock and mineral composition and style of alteration. Contacts between the two can be intrusive or gradational. Rocks collected from these two suites have compositions that are permissive of a single magma batch, although simple crystal fractionation does not explain all chemical variations within and between the two suites. The Sugarloaf unit comprises a diverse group of amphibole-phyric rock types and is texturally and mineralogically distinct from Pothook and Cherry Creek suites.The Iron Mask hybrid represents progressive stages of physical and chemical interaction between Nicola Group country rocks and Pothook magma. Magmatic assimilation (selective or partial) is supparted on the basis of field relationships, petrographic observations, and REB compositional data. Thermal dehydration and partial assimilation of Nicola Group rocks by Pothook magma is shown to be a valid means of promoting early and extensive volatile saturation in the Iron Mask batholith."

Jan 1, 1995

By M. Barati, K. Ebrahimi-Nasrabadi, P. W. Scott

"The conversion of cryptocrystalline magnesite to caustic magnesia was studied experimentally at temperatures of 400–1,200°C and for calcination times of up to 8 h. A differential thermal analysis– thermal gravimetric analysis showed that decomposition begins at temperatures as low as 340°C and is completed at 600°C. Specific surface area, iodine adsorption number, crystallite size, and loss on ignition were measured to characterize the product quality. It was found that high-quality caustic calcined magnesia can be produced in a narrow temperature (600–650°C) and time range (1–4 h).RÉSUMÉ La conversion de magnésite cryptocristalline en magnésie caustique a été étudiée de manière expérimentale à des températures de 400 à 1200 °C et pour des temps de calcination atteignant 8 heures. Une analyse thermique différentielle – analyse thermique gravimétrique montre que la décomposition commence à des températures aussi basses que 340 °C et qu’elle est complète à 600 °C. La surface spécifique, l’indice d’adsorption de l’iode, la taille des cristaux et la perte au feu ont été mesurés afin de caractériser la qualité du produit. Il a été trouvé qu’une magnésie caustique calcinée de grande qualité peut être produite dans un petit écart de température (600 à 650 °C) et dans une période de temps variant entre 1 et 4 heures."

Jan 1, 2015

The following briefing is intended to provide an overview of the present and future challenges associated with our access to a secure and adequate supply of electrical energy necessary to support safe, productive and sustainable mining initiatives at Musselwhite. Contents ??Site power demand vs. current available supply ??Supply technical deficiencies ?adequacy and security of present supply ??Present internal generation ??Anticipated future internal generation requirements ??Increased requirements necessary for planned expansion ?demand/security ??Goldcorp?s strategy to achieve required supply ?transmission line initiative ??Subsequent benefits to others from the Goldcorp initiative. ??Economic impact of MusselwhiteMine on the northwest region ??Anticipated economic impact of planned expansion ??Expected life cycle of MusselwhiteMine ??Comparative energy costs for similar operations in other jurisdictions ??Conclusions ??Anticipated action plan ??Energy Management Initiatives ??Site Orientation

May 1, 2009

By D. M. Watson

Mineral discoveries and subsequent extraction have led to the establishment of many small communities, some major towns and a few cities . In Canada, such developments have essentially occurred without benefit of long-range regional or local planning. In the past, this was not a cause for concern. Now, however, rising expectations and reorientation of social values have placed increasing responsibility on government and industry to ensure the long-term viability of communities and regions. Such responsibility means large investments by government in infrastructure and by industry in extractive and processing plants. Uncertainty in the interpretation of ore reserve estimates becomes a critical factor. The traditional methods of reporting reserves - "proven", "probable" , "possible" - may be useful in individual mine production planning, but they are inadequate for planning industrial and public infrastructure, The need for a better information base is critical, with clear and precise definitions of what is being reported, but we are a long way from achieving it. The challenge is therefore to develop a closer professional relationship between government and industry and to tie mineral development to long-range regional strategies.

Jan 1, 1977

By C. A. Pickles, K. Mackowiak, D. Gajonera

"Shake-flask oxidation tests were performed on Red Dog mine waste to study the initial dissolution behaviours of lead, zinc, and iron. The conditions for accelerated acid generation in terms of Eh and pH were determined. Each mineral behaved distinctly, with galena dissolving first, followed by sphalerite, then pyrite, although there was some overlap in behaviour. Iron was not detected in solution until approximately day 40 and was present at low concentrations. The experimental conditions and the theoretical model results indicated the formation of iron oxyhydroxides at low weathering times and jarosite at longer times.RÉSUMÉ Des tests d’oxydation par agitation en flacon ont été effectués sur les déchets miniers de l’exploitation Red Dog afin d’étudier les comportements initiaux de dissolution du plomb, du zinc et du fer. Les conditions entraînant la production accélérée d’acide en termes d’eH (potentiel d’oxydoréduction) et de pH (potentiel d’hydrogène) ont été déterminées. Chaque minerai se comportait différemment ; la galène a été la première à se dissoudre, suivie de la sphalérite, puis de la pyrite, mais un certain chevauchement des comportements a été observé. La présence de fer en solution n’a été détectée qu’après environ 40 jours et ce, à de faibles concentrations. Les conditions expérimentales et les résultats du modèle théorique signalaient la formation d’oxyde-hydroxyde de fer sur de courtes périodes d’altération atmosphérique, et de jarosite sur des périodes plus longues."

Jan 1, 2017

By W. A. Jankola

Teck Cominco Metals Ltd. operates an integrated zinc-lead smelter at Trail, British Columbia, Canada. The zinc circuit comprises three parallel operations: conventional fluid-bed roasting, direct zinc pressure leaching of concentrates and atmospheric leaching of zinc oxide fume recycled from the lead smelter. The products from these three areas are combined in the main leaching plant where they undergo iron purification. Unlike most leaching circuits, the leach process in Trail begins with an acid leach and is followed by a neutral leach. An evaluation was undertaken to determine if the process at Trail could be improved by converting to the conventional neutral leaching process with a subsequent acid leach of the residues. This paper explores the results of these tests and the implications for Trail Operations.

Jan 1, 2006

By P. L. Li, B. X. Song, C. H. Wang, T. Wang, Z. Hu

"The treatment of an oxidized copper-gold ore by stage cyanide addition was investigated. For cyanidation, free cyanide ion concentration can be an indicator of whether there is copper dissolved in cyanide solution, and maintaining the free cyanide ion concentration lower than 1.0 g/L could be an effective way to prevent copper dissolution and reduce cyanide consumption. For that purpose, stage cyanide addition was introduced to control free cyanide ion concentration within the range from 0.8 to 1.0 g/L. Cyanidation tests results indicate that gold extraction was still acceptable at reduced cyanide consumption with a lower copper extraction. Based on the experimental study, industry application works at Beiya concentrator of Yunnan province, China were successfully conducted. When the raw ore contains 2.95 ppm Au and 0.75% Cu, by stage cyanide addition method, the gold extraction was still 93% at reduced cyanide consumption of 2135 g/t, which was only half of one addition method, and the copper extraction dropped to only 5%, which indicated that dissolution was prevented for almost 75% of the malachites.INTRODUCTIONCyanide with its competency to form a strong complex with gold, is the most preferable lixiviant for gold leaching. However, cyanidation is not inherently a selective process since many other minerals present in the ore are also readily soluble, especially the copper minerals. Muir (2011) reported that every 1% reactive copper present in the ore consumes about 30 kg/t NaCN, which can have detrimental effects on the process efficiency and economics due to high cyanide consumption, reduced gold leach rates and poor gold recovery."

Jan 1, 2016

By L. C. Lien

Tower crane layout (TCL) is a typical construction site layout (CSL) problem, which is suitable for a wide range of work assignments and site conditions. Tower crane is one of the key facilities for vertical and horizontal transportation of materials, especially for heavy prefabrication units such as steel beams, ready mixed concrete, prefabricated elements and large panel formwork such as machinery and equipment, and a wide variety of other building materials within a construction site. However, it is a difficult combinatorial optimization problem to determine the locations of tower cranes with materials quantity supply and demand for engineers. Swarm intelligence (SI) was very popular and widely used in many complex optimization problems which was collective behaviour of social systems such as honey bees (bee algorithm, BA) and birds (particle swarm optimization, PSO). This study applied a hybrid swarm algorithm namely particle bee algorithm (PBA) based on a particular intelligent behaviour of honey bee and bird swarms by integrates theirs advantages. This study compares the performance of PBA with BA and PSO for a proposed hypothetical construction engineering of TCL with materials quantity supply and demand problem. Results show that PBA performs better performance than the mentioned algorithms on a proposed hypothetical TCL problem.

Aug 1, 2013