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By Ryan W. Siggelkow

Mines today use various methods of mining to extract ore. Because of the dangerous nature of many of these processes, remotely controlled LHD machines are being used to extract the ore from the draw point. The remote control system, although being made safer all the time, has remained virtually unchanged for many years. The basic functionality is an operator switching the machine to remote control, getting out of the cab, walking up a stand, operating remotely, returning to the cab, switching to manual, driving manually, switching to remote, and switching to manual. It seems repetitive, and time consuming, does it not? Networking, convergence, video, voice, and data infrastructures, and other technologies are growing by leaps and bounds in virtually every industry and region, except for mining. From the comfort of the living room couch, a Canadian can play hockey online with full voice conversations over the Internet with someone in Russia in real time. Yet, a mine superintendent must jump through hoops to have a private conversation with the front line supervisor underground. "Is Joe around anywhere?" If Joe hears the message, he will respond. If not, who knows? Maybe he's hurt. Maybe he's not. Where is Joe? Nobody really knows, and that is scary. Today, surface knows that the workers disappeared into the cage at 7:00 a.m. They also know that the workers will probably and hopefully return at 3:00 p.m. Is there not a better way to handle this? With such a complex industry, it seems as if, for the most part, the introduction of new technology into mining has either been overlooked or has been met with some resistance. It is time to step back, look at the process, and see how it can be improved. Key areas of focus will be safety, productivity, dependability, and cost-effectiveness.

Oct 1, 2010

By W. E. Roscoe

The probability of making an exploration discovery in Canada can be calculated from Derry's (1970) data on exploration expenditures and number of discoveries over the last nineteen years. Considering an average exploration "try" to be $30,000, the probability of a discovery with one try has decreased tenfold from about 0.01 in 1951 to 0.001 in 1969. A plot of these probabilities can be extrapolated to the future, giving a 1969-71 three-year average probability of 0.00096 with 90 per cent confidence limits of 0.00042 and 0.00153. Using this probability, various calculations can be made, such as (1) the probability of making at least one discovery for any given exploration expenditure, (2) the probability of ultimate ruin or survival of the exploration investment process and (3) the expected value of an exploration investment. There is a critical minimum amount per discovery that must be re-invested in exploration, no matter how large the original investment is, for exploration to survive at all in the long run. Currently, this critical minimum is $31,200,000 with 90 per cent confidence limits of $19,600,000 and $71,400,000.

Jan 1, 1971

By Michael Zurowski

This paper traces the history of International Mogul's assessment program on the Lake Ainslie barite-fluorite deposits of Cape Breton Island. The geology of the area is outlined, and the main vein systems described. The geophysical and geochemical exploration techniques employed are explained, the metallurgy of the ore is covered, and the market prices and economics of operation are described.

Jan 1, 1972

By J. Makgatho, P. Condori, J. Winnett, Fischerm D.

"Palabora Mining Copper (PMC) has two autogenous mills that have been in operation since 1976. The mills were originally designed to treat 30 000 t/d of open cast copper ore in a closed circuit with cyclones. As the ore body went deeper the open cast method of mining was changed to block caving, a consequence of this was the dolerite content (hardest barren material) increased significantly, increasing the production rate of pebbles and thus reducing the milling capacity. In order to cope with the increased ore hardness and to increase mill capacity, a second ball milling stage and pebble crushing were incorporated to the circuit. The above actions created new challenges to the circuit operation and bottlenecks in different areas of the milling circuit.This paper reports the holistic work performed on the Palabora autogenous milling circuit including the implementation of a mill constraint control scheme, the implementation of a pebble removal system from the circuit and a new circuit configuration."

Jan 1, 2012

By R. E. Baylis, M. R. Tolley, S. Singh, A. J. Murray, R. Boden, L. E. Macaskie, T. P. Hathway, D. Vavlekas

We report rare earth element (REE) recovery using immobilized Serratia biofilm depositing metal phosphate via a robust enzymatic mechanism. Activity was approximately halved at pH 3.5 and restored at pH 5.5. REE(III) was recovered selectively against Th(IV) but the method was non-selective between different REEs (La, Y, Eu, Nd). Biofilms were active for a year (half life of ~ 3 months). The activity of aged biofilm was enhanced by pre-nucleation (‘priming’) with NdPO4 prior to onset of flow-through conditions. The use of different ‘priming’ metals and bacteria via a combinatorial approach revealed some REE selectivity through the selective exclusion of specific REEs.

Jan 1, 2014

By A. Singh

Deformation structures after tensile and compression tests on Mg926Zn64Y alloy extruded at 250°C and 400°C are studied, in as-extruded and heat treated conditions. The icosahedral phase particles stimulate recrystallization during extrusion, resulting in fine grain size. Tensile and compression tests at room temperature show comparable yield strength, with a yield asymmetry ratio up to 0.98. c-type dislocations are observed in the grains near the submicron size icosahedral phase particles. The source of these dislocations is believed to be dissociation of <c+a> type non-basal dislocations. No dislocation pile-ups on icosahedral phase particles are found. {10 1 2} type twinning occurs in compression.

Jan 1, 2006

By M. Zavvari

Flotation, as with most engineering disciplines, involves testwork. Commonly this means going from lab scale to pilot scale to industrial scale. It is important to conduct tests to identify key parameters and to optimize even at the lab scale. To reduce the number of tests while maximizing the information, it is necessary to use Design of Experiment and Statistical Analysis. In this communication Fractional Factorial Design was used to identify the effect of 7 main factors on barite flotation recovery from jig gravity tailings at the Dorrin Kashan operation. The factors include: pH, collector and depressant dosage, impeller speed (RPM), pulp dilution, particle size and flotation time. By analysis of the output with Minitab software all factors were shown to have an effect. Among the factors, pH and flotation time have an interaction effect but the others have wise effect as an interaction effect and main effect. Finally, reliability tests at pH= 9, RPM= 1000, collector 1 000g/ton, depressant l 750g/ton, particle size 90 µm, flotation time 90 s, pulp dilution 23 % solids, the optimum level of each factor, were done. At the optimum level a barite concentrate with average specific gravity 4.308 g/cm3, average grade 93.72% and average recovery 90.04% was produced from the jig tail.

Jan 1, 2009

By K. Trapani

"The study undertaken aims to investigate an ice stope heating and cooling system for its potential to be implemented in sub-arctic mines, as a low carbon alternative to conventional natural gas and refrigeration chiller systems. Its performance was simulated for a years’ worth of data, taking into consideration hourly temperature data. Results showed that to supply the required heating and cooling loads, the ice stope system had to supplement its heating with natural heating. The techno-economic performance of this system was compared to that of a conventional heating and cooling system in a mine, with the ice stope thermal storage system hawing the lowest annuitized cost and significantly lower carbon emissions.INTRODUCTIONConventional heating and cooling, in a mine is implemented using natural gas heaters and chiller refrigeration systems respectively. This results in a significant portion of energy consumption in underground mines attributable to ventilation (De Souza, 2015), including the conditioning of the air to ensure that temperatures do not exceed work comfort standards (ACGIH, 2011). Especially at depth where heat could become a significant issue. An ice stope thermal storage, using ice as the storage medium is being proposed as an alternative to provide the heating and cooling—with the ice creation resulting in heating and the ice melting providing the cooling required. A techno-economic investigation of the two systems is undertaken to identify the capital and operating costs for the two systems, and to assess the ice stope’s potential to be considered a low cost and carbon solution for heating and cooling of mines in sub-arctic climates.NATURAL STORAGE SYSTEM – CONCEPT DEVELOPMENTThe concept for the natural storage system is developed from the ice stope at Frood-Stobie Mine, ON, Canada (Stachulak, 1991). The ice stope was developed for mine air heating, with the heating occurring by spraying warm return service water onto the cold intake air—resulting in the air temperature increasing and ice being created in the stope. In summer this ice was melted by passing warm air on top of it, resulting in slight cooling of the air but no significant temperature difference which could allow effective cooling. A schematic of the Frood-Stobie Mine ice stope is provided in Figure 1."

Jan 1, 2019

By S. R. Stopic

The EU-financed INTREAT Project (Integrated treatment of industrial wastes to¬wards prevention of regional water resources contamination) addresses the environmental pollution associated with solid and liquid wastes/effluents produced by complex sulphide ore mining and metallurgical activities. The results concerning the electrolytic recovery of cop¬per from effluents formed after mixing of streams from Copper Refining, Precious Metals Plant and Electrolyte Regeneration in the Balkan Area will be shown. The waste water is characterized by low pH values and high contents of heavy metals, such as Cu, Ni, Bi, As, Sb. The majority of these waste water flow untreated into the natural water streams and through the network of existing rivers, which end up in the river Danube. The influence of current density and flow rate on the deposition rate, the quality of copper and the process efficiency will be presented. The full continuous process is based on cells with rotating disc cathodes and represents a pre-treatment step before common neutralisation in a cascade line

Jan 1, 2007

By W. G. Stevenson

With the author's background of extensive experience, this paper delineates the role of the prospector in modern-day exploration programs. The stages in the development of a prospect to a producing mineral district are outlined, and examples are given from the Ross River area of the Yukon Territory and the Peachland and Highland Valley areas of British Columbia.

Jan 1, 1970

By B. R. Johnston, K. D. Streeter

"ABSTRACTCoal Mountain Operations is the newest of Fording Coal’s operations although it is the oldest in terms of its historical production. In October, 1994, Fording purchased the former Corbin Creek/Byron Creek Mine. The mine is located in southeastern British Columbia, approximately 150 air kilometers from Calgary, Alberta. It was first developed in 1905 and has gone through a variety of owners in its 90-year history.This paper will deal with the remobilization strategy and the mining plans for the operation which are being implemented to make this operation competitive in the world export coal market. IntroductionIn October 1994, following a due diligence process, Fording Coal Limited purchased Coal Mountain Operations from Corbin Creek Resources, an employee group which had previously owned the mine. The purchase awarded Fording Coal Limited with 100% of the assets, and control of all the coal leases at Coal Mountain.The mine is located in southeastern British Columbia, southeast of Sparwood at the hamlet of Corbin, (Fig. 1).Rehiring of laid-off employees started in November 1994, with mining activities also recommencing in November. The coal preparation plant was restarted in December with one shift, went to two shifts in January 1995, and had four-shift, full-time operation in April 1996."

Jan 1, 1997

By Kenneth M. Haley

THE development of Reserve Mining Company's pelletizing practices began in 1949 in a pilot plant located at Ashland, Kentucky. Three years later the participating companies -Armco Steel Corporation, Cleveland Cliffs Iron Mining Company and Republic Steel Corporation concluded the work and the small plant was shut down. Oglebay Norton and Company was the operating manager and Armco Steel Corporation furnished labor and services. Arthur G. McKee and Company were the designers and constructors. The equipment flow sheet that was employed in that pilot operation is shown in Figure 1. This was Reserve's first step from the laboratory work per-formed by the Mines Experiment Station of the University of Minnesota in developing a commercial operation. The plant used New York state concentrate, purchased from Jones and Laughlin Steel Corporation's Benson Mine. This concentrate, minus 14 mesh, 64.3 per cent Fe, 5.7 per cent Si02, was processed at Ashland to 80 per cent minus 325 mesh in conventional ball mill, classifier, thickener, filtering

Jan 1, 1961

By William E. Roscoe

"Non-producing mineral properties include those at various stages of exploration, properties at the pre-feasibility or feasibility stage, properties with currently uneconomic mineral resources, and past-producers. The market approach is applicable to all these types of non-producing mineral properties. Income approach methods such as discounted cash flow and option pricing are generally not applicable to properties at the exploration stage, but may be applicable to non-producing mineral properties with defined mineral reserves or mineral resources.The value of a non-producing mineral property depends on its perceived potential for the existence and discovery of an economic mineral deposit. The potential, in turn, depends on a number of factors which must be considered when choosing market comparables. These comparability factors include such items as geology, mineralization, stage of exploration and results, mineral resources, location and geography, and political jurisdiction. The date of the market comparables must be within a reasonable time period of the valuation date of the subject property. Although it is difficult to find good market comparables because of the unique nature of mineral properties and the small number of transactions, these difficulties are compensated for by analyzing a number of transactions on similar properties to develop a range of values for the subject property.For valuation purposes, market comparables can be expressed in terms of total property value, value per unit area (e.g., $ per hectare), or value per unit of metal contained in mineral resources (e.g., $ per ounce of gold, or $ per pound of copper). The market comparable value can be used to estimate the value of the subject property by using the total property value, unit area value or contained metal value."

Jan 1, 2003

By B. Hart, D. J. Miller, J. T. Francis, M. C. Biesinger, Smart. R. St. C.

Diagnosis of the surface chemical factors playing a part in flotation separation of a valuable sulfide phase requires measurement of the hydrophobic and hydrophilic species that are statistically different between the concentrate and tail streams. Time of flight secondary ion mass spectrometry (ToF-SIMS) can be used to identify sufficient particles of a specific mineral phase for reliable statistics determining a mean value for each species with 95% confidence intervals (1). Using the region of interest (ROI) facility in the Tof-SIMS software, a mass spectrum from each particle, at 1-2 monolayer sensitivity, is recorded and stored. This analysis is reported for a chalcopyrite / pyrite / sphalerite mineral mixture conditioned at pH 9 for 20 minutes in order to study transfer of copper from chalcopyrite via solution to the other two mineral surfaces since this mechanism can be responsible for their inadvertent flotation in copper recovery. Analysis from mineral selection based on specific ToF-SIMS signals (eg. Pb, Zn, Cu, Fe, Fe/Cu) indicated no statistical difference in the copper intensities on pyrite and sphalerite after this conditioning. Principal component analysis (PCA) of the ToF-SIMS imaging data identifies combinations of factors strongly correlated (positively or negatively) in images or spectra from mass spectra recorded at each of 256x256 pixels in a selected area of particles. PCA is a better method of selecting minerals due to multi-variable recognition. It has clearly separated a statistical difference in copper intensities between the sphalerite and pyrite phases. The method has been extended to samples from an operating plant again with excellent phase recognition and diagnostic surface chemistry.

Jan 1, 2004

By S. C. Tadolini, J. M. Goris, J. L. Gallagher

Cable supports offer several advantages over traditional secondary support methods by enhancing stress redistribution to pillars and gob areas, minimizing or eliminating timbers and cribs that reduce ventilation, eradicating material-handling injuries related to placement of crib supports, and providing a cost-effective alternative to secondary support. The U.S. Bureau of Mines (USBM), researching alternatives to traditional roof support methods, designed and installed high-strength cable supports to improve the stability of longwall gate road entries in a western U.S. coal mine. With the cooperation of industry, methods were developed to install and evaluate cable supports in a tailgate area using traditional resin cartridges. The cable-bolted areas successfully maintained roof support throughout the developed entries. Cable supports have replaced wood cribbing as secondary support in the bleeder entry system and have minimized or eliminated the use of cribbing in the longwall tailgate entries. This paper describes the theory, application, and advantages of cable supports and presents some mine measurements made to assess the cable performance during the retreat process of longwall mining.

Jan 1, 1999

By A. Rahimi

Refractory castables based on alumina-silicate aggregates are commonly used in casting wheel components and launders. In this research the recycling process of waste magnesia chrome bricks for production of refractory castable lining for launders and casting wheel ladles at Iranian Sarcheshmeh copper complex (I.S.C.C.) is discussed. The smelting plant of ISCC consumes 4,000 tons refractory materials and produces 2,000 tons waste refractories annually. In order to reduce the environmental pollutions and gain the economical advantages, the recycling of waste refractories proved to be a solution [1]. In ISCC, 800 tons alumina or alumina-silicate refractory castables are used for linings of anode furnace ladles and launders annually [2]. In the present work, the spent bricks from reverberatory, converter and anode furnaces were analyzed in term of microstructural changes from hot zone to the cold end to evaluate the changes in texture and chemical composition. Different formulations based on recycled magnesia chrome aggregates and various particle size distribution and cement content were tested. Economic recycled magnesia chrome refractory mixture was prepared after crushing and sizing the non-deteriorated regions of wasted bricks. After evaluation of physical and mechanical properties of samples, one ton of refractory castable was prepared and successfully installed in the casting wheel ladles.

Jan 1, 2007

By Leroy C. Stewart

Owing mainly to the use of ethylene dibromide in the production of tetraethyl lead for gasoline treatment, there has been a tremendous increase during the past decade in the demand for bromine. In the United States, production, derived mainly as a by-product from the treatment of brines from salt wells, rose steadily from about two million pounds in 1924 to nine million pounds in 1931. In 1936, production amounted to between 20 and 21 million pounds. Much of the increase during the past four or five years has been due to the operation of the Ethyl-Dow Chemical Company&apos;s plant, which extracts bromine directly from sea water. The process employed by the Ethyl-Dow Company is somewhat similar to that in use on salt-well brines at their plant at Midland, Michigan, but whereas these brines contain around 1,300 parts per million bromine, sea water contains only 65 to 70 p.p.m.-about as much as the waste effluent in the brine process. By intensive research, however, a process was developed whereby a very considerable percentage of the bromine content of sea water could be recovered, and at a satisfactory operating cost. In its essentials, the process consists in liberating the bromine from the sea water by treat-ment with chlorine, blowing the bromine out of the water by a current of air, and finally absorbing it in a solution of soda-ash.

Jan 1, 1938

By F. F. Langford

"The Athabasca Basin occupies about 100,000 km2 of the northwest corner of Saskatchewan with its western margin extending about 50 km into Alberta (Fig. 1). The basin is filled with a Helikian sequence of predominantly fluvial sandstones up to 1600 m thick. The sandstone beds are generally flat-lying, and rest unconformably on a crystalline basement which consists mostly of granitic intrusive complexes and quartzfeldspar- biotite gneisses. The basement rocks represent Aphebian sediments and Archaean basement rocks that were metamorphosed and remobilized to varying degrees during the Hudsonian Orogeny (ca 1800 Maj.Since 1968, three mining camps and several substantial unconformity-type uranium deposits have been discovered in the area (Figs. 1 and 2). These deposits lie along the unconformity surface, partially enclosed in sandstones, and partially in the basement rocks. The major deposits have elongate, pencil shaped orebodies that are parallel to the strike of underlying graphitic biotite gneisses. The total tonnage of uranium is in the order of 150,000 to 200,000 tonnes and mining grades range from 0.5 to 2.5 per cent U3O8.IntroductionUranium exploration started in Saskatchewan in 1945 when Jolliffe and Murphy headed field parties to investigate uranium occurrences on the north shore of Lake Athabasca (Kupsch, 1978). Their investigation lead to the development of the Beaverlodge camp in the following years. Some of the early prospectors were impressed by the fact that the uranium occurrences at Beaver lodge were centred on a thick sequence of unmetamorphosed arkosic redbeds which are now called the Martin Group. This sequence was referred to as the Athabasca Series by Christie (1949), and although some occurrences of uranium were found near Stony Rapids and Black Lake, the vast expanse of Athabasca sandstones south of Lake Athabasca was generally regarded as unpromising."

Jan 1, 1986

By E. M. Hillary, D. F. Sangster

"Abstract - As a contribution to the World Minerals Geoscience Database Project, an index-level database comprising information on 142 SEDEX Pb-Zn deposits and occurrences was constructed in Microsoft Access 95 format. Although consisting of only basic information, the compilation, with full referencing of all data, is possibly the largest non-corporate SEDEX Pb-Zn database in the world. It thus provides an opportunity to make geoscience queries of SEDEX Pb-Zn deposits on a scale not previously available. This report provides a summary of the results of a few such queries both as a contribution to a better understanding of SEDEX lead-zinc deposits and as a demonstration of what even such a simple database can offer.During the compilation process, it became apparent that SEDEX Pb-Zn deposits could be assigned to one of the following three sub-types: Type 1 (53.5% of total) in which sulfide minerals are the only exhalative components; Type 2 (33.1%) in which the exhalative components are sulfides plus chert, siderite/ankerite, and/or barite; Type 3 (13.4%) which contains any components of Types 1 and 2 plus abundant iron-oxide minerals (commonly magnetite) and/or is associated with iron oxide-rich sedimentary rocks.Highlights of systematic queries of the database reveal that:1. a majority (84%) of the world’s SEDEX Pb-Zn deposits are not underlain by a discordant footwall feeder zone or vent complex;2. 63.6% of deposits occur in Proterozoic strata followed by a second peak in the Devonian (16.8%). Of those in the Proterozoic, 83% of Type 3 deposits occur in the Gondwanaland supercontinent, whereas only 42% of Type 2 and 39% of Type 1 are located in this large paleo-landmass;3. median (Pb+Zn) grades in Types 1 and 2 fall between 9% and 10% with a majority clustering within this range. Type 3 grades, however, range from ~1% to ~20% (Pb+Zn) with a median of 5%; 4. median size of Type 3 deposits is ~33 Mt, whereas Type 1 and 2 median sizes are ~7 Mt and ~8 Mt, respectively.The report concludes with a brief discussion of how an index-level database such as this can be used in conjunction with other, similar databases to reveal interesting and instructive relationships for guiding both research and exploration."

Jan 1, 1998

By R. S. Bigelow

Part 1.- Metal Mines Early experiments with mechanical loaders in metal mines were confined largely to machines of the shovelling type and generally air-operated. Although the first application of the scraper to metal mines dates back to 1910, it was not until about twelve years ago that it came to be used extensively. Generally, the scraper gives better results in metal mines than in coal mines, as degradation due to soft bottom and breakage are not factors, but it has a wide range of application and is successfully used in the mining of salt, potash, gypsum, zinc, copper, and a variety of ores, from soft material to hard chunky ore which settles compactly. Today, the scraper has replaced to a large extent the shovelling type of machine in metal mines. Scrapers have offered an inexpensive solution for the mucking problem and are now employed in most mining districts throughout the world. They are operated by labourers of all colours and degrees of skill. Each installation, however, requires individual study on the part of the mine mechanical department to determine the type of scraper, horsepower of hoist, and most economical speed of rope, as well as method of rope rigging. Unfortunately, the scraper has no power to select pay ore from waste and its suitability for use under circumstances which might require sorting of the ore can only be decided by a weighing of the economic factors involved

Jan 1, 1931