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By G. W. H. Norman

"The Indian Molybdenum deposit occurs in granite near the centre of Indian peninsula, Kewagama lake, in Preissac township, Abitibi county, Quebec, about 40 miles east of Noranda. Quartz veins containing molybdenite were discovered in the vicinity of the deposit in 1901 by J. F. E. Johnston of the Geological Survey of Canada. Innumerable trenches and a few pits were excavated during and prior to the first great war, but there was no production. During the second great war systematic drilling along a favourable zone disclosed by the earlier trenching outlined an orebody of 225,000 tons with a molybdenite content of 0.46 per cent.A 500 on mill was built in 1943, and 91,489 tons of ore underwent treatment, from which 699,568 lb . of molybdenite was recovered. The mill closed down early in 1944 when the wartime need for Canadian molybdenum production eased .GEOLOGYThe general geology in the vicinity of the deposit is shown in Fig. 1. The deposit lies at the north edge of a muscovite-biotite granite mass about 2 miles wide and several miles long. West of Kewagama lake this granite is cut by great swarms of quartz veins . The only other granite in the district known to contain similar swarms of quartz veins, and which similarly has become a source of mo!ybdenite, occurs 20 miles east in La Corne township. The non-molybdenite-bearing granites of the district are either more basic and contain frw dykes except aplite or are distinctly pegmatitic types and contain up to 50 per cent pegmatite dykes with molybdenite only here and there in small amount."

Jan 1, 1954

By B. S. Fee, R. R. Klimpel

"Froth flotation is the most widely used and economic means of concentrating metal sulfide ores such as those containing copper, lead, zinc, nickel, molybdenum, and pyrite. Also recoverable are other metal species that are often associated with sulfide ores such as cobalt, platinum, gold, silver, etc. Most of the initial developments made with the process of froth flotation in the early 20th century were based on the processing of metal sulfide ores. It is the relative technical and economic ease of floating metal sulfide minerals with small amounts of appropriate frothers and sulfur containing (thio) collectors that has been a major economic driving force behind the rapid expansion in the supply of metals such as copper, lead, zinc, and nickel that has occurred in the world's economy in the last 50 years. This author estimates that 1.6 billion tons of sulfide ores are processed each year (1980) in the free world based on the froth flotation process.While there has been a tendency for the quality of metal sulfide ores in any one geographic location to deteriorate over time due to mining intensity, the overall global supply of sulfide minerals is still very large. Thus, the physical supply side of sulfide ore concentrates has not been under strong technology improvement pressure with increasing metal demands. Part of this is due to the ability of capital to consistently move to new geographic locations having suitable grade sulfide ores. In these moves, the actual froth flotation technology used (including collector chemicals) has had to change little. As an illustration of this trend, of the approximately 80,000 metric tons of thio collectors used commercially (1980) in the free world, almost 98% were known and manufactured in some form 25 years ago (1). This is clearly not typical of reagent development in other process related industries. In addition, the industrial scale practice of froth flotation applied to sulfide ores has proceeded since the 1920 s with often little direct (predictive) scientific explanation due to the extreme complexity of the flotation process. Empirical testing has been a mainstay of industrial flotation reagent development and use. Even today there is often strong disagreement between researchers as to the mechanisms of chemical flotation practices that have been performed successfully at an industrial scale for many years."

Jan 1, 1987

By T. G. Joseph, G. W. Hansen

"This paper considers the duty cycle of an electric cable shovel and correlations with measured passive seismic responses of the underfoot oil sands material in-pit. It has been observed that the cyclic activity during operation of any shovel in the oil sands environment causes the material to deteriorate and provide a less than ideal footing for this large item of equipment, whose dead weight approaches 1500 tons with a footprint of merely 75 sq. yd. Consequences are manifested in the form of carbody and side frame cracks, and associated downtime, maintenance activity, cost, and subsequent loss of availability.The objective of these considerations, as part of the Oil sands-Equipment Interaction Program (OsEIP), currently a joint venture between Syncrude Canada Ltd., James Progithin International (JPi) Ltd., Caterpillar Inc., P&H MinePro and the University of Alberta, is to identify and provide feedback to the manufacturer and end user of adverse shovel-ground conditions. This would enable the manufacturer to incorporate greater knowledge into the design process and the end user to direct operations in an enhanced proactive maintenance stance."

Jan 1, 2002

By Greg Gosson

"Early efforts to develop formal reporting systems to quantify and classify mineral deposits date back over 100 years. (e.g. Hoover 1909: “Proved, Probable, Prospective Ore”). This was at first driven by mine operators’ need for reliable estimates of what their mines could produce. Disruption of transportation routes by world wars prompted western governments to recognize the need for assessments of strategic sources of metals and minerals that could support domestic industry during times of crisis. Categories were created to quantify mineral potential which were additional to those of mine reserves. Terms such as hypothetical and undiscovered resources entered the lexicon. Capital markets serving the mining industry were traumatized during the latter part of the 20th century by undisciplined and fraudulent disclosure by exploration companies of mineral deposit potential. Government securities regulators pressed for the development of credible reporting codes (e.g. SEC Industry Guide 7: 1981; JORC 1989; SAMREC 1994, CIM 2000). Representative organizations from the major western mining countries generally agreed that there should only be three categories of mineral resources (measured, indicated, and inferred) and two categories of mineral reserves (proven and probable). This was formalized in 1997 with the “Denver Accord”. Acceptance of the standard terminology may have been the easy part, because the challenge for the 21st century is to get general industry acceptance and agreement of the principles behind the definitions of each category. There has been noticeable movement towards this objective in the last few years. This is reflected in part in the updated reporting codes by JORC 2004, CIM 2005; SAMREC 2007; SME 2007; and PERC 2008, and the development of the CRIRSCO International Reporting Template 2007."

Jan 1, 2003

By H. C. Counsell, R. Webber

"The mill at Denison Mines' Elliot Lake Operations started up in 1957, with a capacity of 6,000 tons per day. Over the years various plant modifications expanded th.is to 7 500 tons per day. In 1976, management decided to carry out a major expansion of the milling capacity, and during 1980 the grinding capacity was increased to 15,000 tons per day.The original comminution system consisted of a conventional crushing plant feeding minus S/s-inch material to rod and pebble mills, in closed circuit with mechanical classifiers. The key decision that had to be made was whether the expansion should include conventional or autogenous grinding flow sheets.During 1977, extensive pilot plant studies at Lakefield Research showed that two-stage semi-autogenous grinding, with some steel media in the primary mill and with pebble media in the second stage, produced stable grinding conditions. This type of circuit was selected by Denison for the expansion, and went into production in 1980. Primary millThe flow sheet of the semi-autogenous grinding circuit is shown in Figure 1. The primary grinding mill is a Koppers 28 foot by 10 foot mill, driven by a 4,000 h.p. synchronous motor. It is fed with a minus 8-inch run-of-mine ore, and 4-inch grinding balls are added as supplementary grinding media. There are two Koppers 15.5 foot by 22 foot secondary pebble mills, driven with 1500 h.p. synchronous motors. Each grinding stage operates in closed circuit with cyclones, and the primary cyclone overflow is the feed to the secondary mills. The circulating load in the primary stage can be controlled by adjusting the cyclone apexes."

Jan 1, 1984

By Joe Price

Canada?s energy future will increasingly depend on a supply of light, sweet crude oil derived from the Athabasca oil sands deposit of North-eastern Alberta. Billions of dollars are being spent on the construction of new and expanded mine and bitumen extraction plants, in situ recovery facilities, pipelines, upgrading installations and all the infrastructure needed to support these projects. The success of the existing operators has also inspired new players, anxious for ?a piece of the action? to come forward with exciting project proposals of their own. None of this investment and spin-off economic activity would be taking place today if events had unfolded differently in this part of the world some one hundred million years ago. The accumulation of sand in rivers, estuaries and in the near-shore marine environment created the great reservoirs that host the enormous oil deposits these projects are designed to exploit. Mine operators of all stripes will likely agree that there are few good ?geological surprises?. With specific reference to oil sand deposits, the geological history determines the distribution of sand, silt and clay bodies, which in turn controls the ore grade. Important design factors including everything from stable pit slope angles to tailings properties reflects events that took place millions of years before. An understanding of the sequence of events that resulted in deposition and preservation of the sediment and oil are important to sound design for both mining and in situ facilities. A geological history of the region is described. Site-specific examples from Syncrude?s operating mines are used to illustrate some of the geological factors that can present design challenges.

May 1, 2003

By R. A. D. Pattrick, D. A. Polya, D. J. Marsh, J. -J. Bao

"Abstract-The utility of high-density stream sediment and stream water sampling to the exploration for silver deposits was investigated by the study of the epithermal Ag-Au base-metal prospect at Lagalochan in western Scotland. The geology of Lagalochan is dominated by a calc-alkaline Caledonian intrusive complex emplaced into Dalradian Supergroup rocks (Harris et al., 1988a). The complex consists of subvolcanic porphyrytic rocks associated with intense hydrothermal alteration and brecciation. Early Cu-Ag-Mo-rich mineralization is found in the core of the complex with later Pb-Zn-Ag-Au-As-Sb-rich mineralization toward the margins (op. cit.).Stream sediment sample analysis spatially resolved the Cu-rich and Ag-rich mineralization. Ag and Cu anomalies relative to local background values were found in all size fractions analyzed (-125 µm, +125 µm, +180 µm, +250 µm) but the more pronounced anomalies were found in the -125 µm fraction. The coarser fractions generally revealed more erratic but longer dispersion trails. The separation of Cu-rich and Ag-rich mineralization is also apparent in the distribution of relatively high dissolved Cu and Ag in stream waters, particular when expressed relative to the solute load as Cu/TDS and Ag/TDS.The mineralization at Lagalochan is indicated by Ag, Cu and Pb stream sediment and water concentrations that are anomalous with respect to local backgrounds, but are difficult to distinguish from regional backgrounds. This emphasizes the further potential of high-density stream water sampling, in particular, as a viable geochemical exploration tool on a sub-regional scale for epithermal deposits in relatively unpolluted upland terranes."

Jan 1, 1995

By Tobias Riedel, Peter Ay, University of Applied Sciences, Bianka Bade, Nicole Pausch, Bernhard Gemende, Florian Logsch, Matthias Leiker, Satyanarayana Narra, Claudia Glaser

This study focusses on the production of micro-structured agglomerates with high porosity from iron (III)-hydroxide-containing materials as adsorbent. A fractal-like structure of the agglomerates was created through a two-stage agglomeration process. Developing porous structures was necessary to increase the adsorption capacity. Various materials were used for the agglomeration experiments: i) filter cake (dry matter content 23 to 27 wt.-%); ii) FerroSorp®DGµ, a product which is already being used commercially for various applications in water cleaning. These materials in the pristine state have different characteristics such as dry matter content and particle size distribution. The desired optimised agglomerates can be achieved with the help of additives or binders, respectively. Additionally, the agglomeration process parameters play a vital role. In order to produce agglomerates with high porosity, the process was carried out in two steps. Firstly, FerroSorp®DGµ (d90 < 30 µm) was agglomerated jointly with the aforementioned filter cake in an Eirich intensive mixer (particle size range 125 µm < d90 < 500 µm). The second agglomeration step post drying was carried out in a pelletisation disc or in an Eirich intensive mixer with the addition of polymeric binders (up to particle sizes ranging from 2 to 4 mm). Agglomerates were characterised both in short and long term loading tests using phosphate as model ion. Contact times were less than 10 min, similar to practical application in percolation columns, or more than 7 days, respectively. The results show that the agglomerates produced in the two-stage pelletisation process have more advantageous properties like better accessibility of the active sites obtained by specificly influencing the particle size distribution during the two-stage pelletisation process.

Jan 1, 2016

By P. C. Garg

"IntroductionThe Central Mine Planning and Design Institute (CMPDI) of India, started planning the extraction of thick seams highly susceptible to heating in 1977by the French method of sub-level caving and/or multi-slicing. Nitrogen flushing was proposed for inhibition of heating by the author in one such project - the Kotadih colliery.Inhibition of heating was unheard of in the Indian coal industry before 1977-78. The usual practice was to seal off a district or a part of the mine or the entire mine when spontaneous heating occurred. With very little equipment in a normal bord and pillar district and a low production rate, the financial loss in capital assets and in production did not warrant any serious thought for inhibition of spontaneous combustion. With the planned advent of longwall mining, particularly sub-level caving, with heavy capital investment as well as high production potential, the sealing of a longwall face due to spontaneous heating could not be considered an appropriate solution.Principle of Inhibition of SpontaneousCombustionFrench engineers have established that a fire will not break out when oxygen is 15% or lower in the general body of the air. However, once a fire starts, the percentage of oxygen has to be reduced to 2% - 4% to extinguish it. It is this principle which has been used at Blanzy Coalfield in France to inhibit heating and it is claimed that this has retrieved the integral sub level method of mining. Nitrogen infusion has been used in Frence since 1978 to keep the oxygen content below 14% in the goaf."

Jan 1, 1987

By Mohamad Sabsabi, André Hamel, André Moreau, Paul Bouchard

"Laser-Induced Breakdown Spectroscopy (LIBS) is an atomic spectroscopy technique used to measure elemental concentrations. It is well-adapted to in-situ and in-line measurements during materials processing in general, and pyrometallurgy in particular. It is an optical non-contact technique and it can measure nearly all elements, including light elements. Our group has developed a mobile prototype system to measure molten metals. The system includes a tube, also called a lance, one end of which is immersed in the molten metal. An inert gas flows in the tube and bubbles out below the surface. The LIBS measurement is made through the tube and onto the bubble’s surface. This is done to avoid measuring contaminants, slag, or fluxes often found at the surface of the melt. An added benefit is that the molten surface is constantly renewed and thus, more representative of the bulk. An alternative to using our lance is to use a tuyère, such as a gas injection tuyère in a converter, as we did several years ago in a nickel matte converter. In this presentation, we will show various applications emphasizing more recent developments. This includes the simultaneous measurement of the concentrations of Cu, Ni, Fe, Co and S in molten matte at 1125 °C. The more obvious industrial applications of the technology include determining the best time to end oxygen blowing in the converter and elemental concentration measurement during alloying.INTRODUCTIONThe mining industry continually faces challenges in optimizing cost and productivity. Because of the large volumes of materials that are being processed, small improvement can have a big impact on benefits. Better real-time information can help improve this optimization."

Jan 1, 2016

By L. D. Smith

"Those who submit competing proposals for projects seek to present senior management with complete and fully supported material that will not fail under questioning. Hopefully, misleading notions and omissions will have been minimized and there will have been testing of the assumptions regarding the economic, social and political environments.A capital project evaluation team can do management and itself a service by including a sound approach to the impact of inflation (and its twin problem, interest) on a project and a great disservice with an inappropriate approach to inflation.InflationHandled deftly, inflation can alter a project evaluation to show almost any result the handler desires. It must be a constant source of frustration for design people and cost estimators to spend weeks perfecting the technical aspects of a project in order to minimize costs, only to have all of their efforts set awash in a sea of financial and economic assumptions that submerge all of the detail. In all of this, inflation is perhaps the largest offender, with inflation criteria often being brought to bear at the last minute, almost as an afterthought. Perhaps this tardiness reflects the difficulty of the subject and the belief that senior management will take its own approach to the problems of inflation. Such a belief is unfair to senior management, for it is entitled to not being misled by omission. It is entitled to the full use of the skills of the evaluating team, including reasonable assumptions of the impact of inflation.Working in a consulting context, one has the opportunity to participate in the evaluation of a large number of projects."

Jan 1, 1990

By R. E. G. Caines, P. Alport

"Operating heavy equipment in Labrador, where the winters are 8 months long and the temperature frequently drops below -40°F (-40°C) for days and sometimes weeks presents unique problems in both the operation and maintenance junctions. Winterization programs must be well designed and implemented at the proper time. These programs must include the proper selection of fuel oil, engine oil, hydraulic oils, greases, cooling system fluids, etc. More often than not, modifications have to be made to the original equipment in order that it can be operated safely and economically in the Canadian North. Manufacturers usually design equipment for a less harsh environment and the user makes adaptations by trial and error.Operators have to be trained for the proper operation on ice- and snow-covered roads in an open-pit mine. Special emphasis must be put on haulage road conditions. In this paper, the authors will cover some specific maintenance procedures, equipment modifications and operator training problems experienced by the Iron Ore Company of Canada in its open-pit operation in Labrador.IntroductionT he Iron Ore Company of Canada is engaged in open-pit mining , concentrating and pelletizing of iron ore. The company operates in two provinces, Quebec and Newfoundland (Fig . 1) . The Knob Lake operation "", based in Schefferville, Quebec, has mine sites located both in Labrador and Quebec . The Caro l Lake Project is situated in Labrador, 25 kilometres east o f the Quebec border at Labrador City. The Carol operation mines, concentrates and pelletizes it s o re before rail transportation to the seaport o f Sept-lies via the Quebec North Shore and Labrador Railway."

Jan 1, 1984

By V. Silins, J. Tameling, R. C. Cook

"A general review of the wear problems encountered in the mining industry is presented and current practice for wear protection systems is reviewed.A new concept in wear protection is described and compared to alternative systems. Utilization of conventional stud welding technology and abrasion-resistant wear studs is shown to be a useful supplement or substitution for conventional techniques. Operating life of many consumable components can be increased by up to four fold. The technique is highly portable for on-site field application or can be used in shop environments.Details of the wear protection model and metallurgical properties of the wear component are also reviewed. Laboratory wear test data are reported to supplement field test performance or to screen potential alloy compositions for application in specific environments.A Review of Wear Problems and Wear ProtectionThe emphasis on wear protection has increased in recent years because of the increasing impact of the potential savings in time, materials and energy. A 1974 German study concluded that attention to tribology, the study of friction and wear, could save approximately $3 billion, and a study in the U.S.A. at the same time put the figure at $100 billion of which $20 billion was for materials. A more recent American study put the energy component of the potential savings at $16.2 billion per year. A recent British study estimated the total potential savings in the U.K. as $1 billion per year, with the largest savings coming from lower maintenance and replacement costs ($500 million), lower breakdown costs ($250 million) and increased machinery life ($200 million). These three major contributions are all potentially accessible in the mining industry."

Jan 1, 1982

By Y. Chengxian, F. Yaorong, Xinzhe. L.

Many factors about the HIC (hydrogen-induced cracking) resistance of pipelines are discussed in this paper. The main factors that influence the ability of HIC are environmental and material factors. The chemical compositions, non-metal inclusions and microstructure are discussed in detail, while a group of tests on HIC resistance are done according to varying C, S, Mn and P contents in pipeline steels, different experiment time and different strength to the coupon. It is concluded that decreasing the amount of C and S can obtain good HIC resistance; the test time has an effect on the different microstructure of X70; microstructure is the most sensitive factor for the initiation processes of HIC.

Jan 1, 2005

By Y. Chengxian

Many factors about the HIC (hydrogen-induced cracking) resistance of pipelines are discussed in this paper. The main factors that influence the ability of HIC are environmental and material factors. The chemical compositions, non-metal inclusions and microstructure are discussed in detail, while a group of tests on HIC resistance are done according to varying C, S, Mn and P contents in pipeline steels, different experiment time and different strength to the coupon. It is concluded that decreasing the amount of C and S can obtain good HIC resistance; the test time has an effect on the different microstructure of X70; microstructure is the most sensitive factor for the initiation processes of HIC.

Jan 1, 2005

By D. C. Fraser, W. J. Scott

"Airborne electromagnetic surveys were flown during 1965 in the Moose River area of Ontario. The systems used were INPUT Mark II and the Canadian Aero Otter. Anomalies indicated by both systems were located on the ground with vertical-loop EM. Two such anomalies were drilled, with no explanation being found in the bedrock geology. Subsequent seismic, resistivity and gravity surveys indicated that the sources of these anomalies lay in the overburden. Current work in the similar geological environment of the Winisk River area has shown that comparable AEM anomalies can still be misleading. The lesson to be, learned from these experiences is that additional geophysical work can help to resolve doubtful cases before drilling decisions are made."

Jan 1, 1973

By J. W. Coetzee, H. E. Deist

Carbon-in-pulp (CIP) and Carbon-in-leach (CIL) processes are used extensively in the gold mining sector to recover aurocyanide from solution. This paper discusses the modelling of these operations, using various simplifying assumptions, in order to simulate the effect of changing operating conditions on the dynamics of the system. It is assumed that the adsorption and leaching rates are a function of concentration difference between the source phase and recipient phase. The simulation was set up using Matlab&apos;s Simulink interface. Plant variables are solved using a medium scale Newtonian search algorithm in Matlab, where the differences between the actual and predicted plant outputs are minimized on a continuous time-line.

Jan 1, 2005

By F. Daniel Rosenkranz, Peter L. Silveston

Experiments investigating the treatment of a ground wood white water waste from an Ontario pulp and paper mill by an HVCB coal are reported. Adsorption capacity for the waste, with a soluble COD contribution of 2,100 mg/I, amounted to 0.17 per cent, by weight, of the Nova Scotia coal used. Percolation of the white water waste through a coal bed indicated that soluble COD is removed. For finely ground coals, over 90 per cent of the suspended solids in the waste are retained on the coal. Plugging of the coal bed is rapid, so that any treating process using filtration would have to renew the surface of the bed frequently.

Jan 1, 1970

By J. K. Shaw

The science of low temperature engineering is well entrenched in mining. Uses for common cryogens, including liquid oxygen (LOX), liquid nitrogen (LN2), and liquefied natural gas (LNG) in the gas and minerals industries are reviewed. Potential future applications are discussed within the scope of mining, particularly in refrigeration and ventilation. The second part of this paper focuses on the Linde cycle, which is at the heart of most liquefaction plants. Steady state equations describing the mass and energy flows are presented. The paper concludes by explaining the concept of a wind powered Linde- Hampson cryogenic cycle and assessing, with scoping calculations, the technological feasibility of producing cryogens with an intermittent source of (renewable) energy.

Aug 1, 2013

By Raymond Dallaire

The Humphrey&apos;s spiral is a static gravity separation device which cannot be adjusted to match short-term variations that occur in the feed. Any disturbance in the feed grade, per cent solids or flow rate affects substantially the recovery and grade of concentrate. Such variations must be minimized in order to maintain the desired rate of production and quality of the product for which the installation has been designed. A study has been performed in which the foregoing assertions were quantified. The feed grade, per cent solids, flow rate and particle size were varied independently. Ore from Carol Lake, Nfld., was used throughout the experiments. This consisted of specular hematite and magnetite in a silica gangue.

Jan 1, 1978