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By P. A. Tichauer

Arbitration is a flexible method for dispute resolution that gives control to the disputing parties while still maintaining a clear and well-structured decision making process. It responds to the desires of the parties for a resolution that is fair, binding and enforceable and is guided more by pragmatism, efficiency, effectiveness and equality than by a need to comply with the legal procedures and practices of any single country or jurisdiction. Arbitration is particularly well suited for the resolution of disputes pertaining to international commercial agreements which are often present in the metallurgical sector. This paper provides a simplified outline of the features and advantages of arbitration as well as commentary regarding certain prerequisites in order for arbitration to be binding and enforceable.

Jan 1, 2015

By John C. Luck Jr.

"DEVELOPMENT of oil emulsion mud dates back to the early days of rotary drilling when oil was added to the drilling mud solely for the purpose of freeing stuck drill pipe. After the drill pipe was freed, and drilling resumed, this oil was considered a contaminant. Efforts were made to remove the oil but some of it remained and was emulsified with the drilling mud, thus forming a mechanical emulsion.During the late 1930's, operators found that adding crude oil to drilling muds seemed to alleviate 'sticky-hole' problems and so oil was allowed to remain in the mud. This practice was adopted when it was found that faster drilling rates and longer bit life were obtained. These observations led to the development of emulsion drilling muds. During the past five years their application has become more widespread because of the lower fluid losses obtained, greater lubrication qualities, faster penetration rates, and generally better hole conditions.An emulsion may be defined as a two-phase system consisting of a mixture of either finely divided oil droplets in water or of finely divided water droplets in oil. The surrounding liquid is known as the continuous phase. The emulsifiers reduce the interfacial tension, making the droplets tend to repel each other so that they remain dispersed and stabilized. These emulsions are classified as oil-in-water or as water-in-oil, depending upon whether water or oil, respectively, is the continuous phase. Briefly, close inspection shows that they consist essentially of globules of• the one liquid suspended in a continuous mass of the other liquid. Oil emulsion muds are usually of the oil-in-water type. Two basic types of emulsifiers •commonly used in Canadian muds are soaps and lignites."

Jan 1, 1954

By Damien Gaboury

"Two practical methods for correlating two or more diamond-drill core intersections, using a stereographic projection software are presented. The first may be used to establish if two or more vein intersections are correlative, based on their core angles and diamond-drillhole attitudes. The second method allows prediction of main vein attitudes from numerous intersections, based on a spherical density contouring projection. The methods are suitable for: (1) correlating veins in complex orebodies; (2) ascertaining lateral continuity of ore for reserve estimations; (3) demonstrating the hidden complexity of an orebody; and (4) correlating and interpreting various planar elements.IntroductionModern mineral exploration relies on diamond- drill core data and on the ability of geologists to interpret them. Drill core generally yields unoriented information, unless an expensive orientation device is used. As a consequence, strike and dip of planar elements such as lithological contacts or mineralized veins cannot be determined easily. This is particularly true for blind deposits (covered by thick overburden) and complex orebodies, where field data cannot support drilling interpretations. Such a problem has been addressed previously using two and three diamond drillholes and several solutions were proposed based on trigonometry, and geometric and stereographic projections (Mead, 1921; Wisser, 1932; Fischer, 1941; Stein, 1941; Bucher, 1943; Gilluly, 1944; Addie, 1962; Mills, 1963; Lyons, 1964). However, these solutions are time consuming and not relevant to present day computerized data plots."

Jan 1, 1997

By L. C. DeCory

"Concrete is a common denominator to the building process and portland cement is an integral and necessary component of concrete. The cost of portland cement is nominal and its cost comprises, in most instances, a small portion of the total cost of ""put-in-place"" concrete.The domestic demand for portland cement in Canada is projected to be slightly less than 11 million short tons in 1980. In order to achieve this projected goal, stabilization or lowering of the cost of put-in-place construction is necessary. This enhancement of the cost of building can be achieved by:(1) improving the building process;(2) refining and improving design techniques; and(3) developing improved and economical concrete products.Some of the techniques and materials that will lead to building cost stabilization include systems building in its broadest sense, slipforming, precasting, prestressing, computer design, lightweight aggregates, fibrous concrete and integration of building components."

Jan 1, 1973

By L. K. Daneshmend

The mine of the year 2020 will need to be based on a new way of mining. It will employ technology in a paradigm that assumes responsibility for sustainable development: taking account not only economic but also ecological and social issues. This will require a holistic approach to mine design and planning, considering all controlling factors and impacts (technical, economic, environmental and social). A national collaborative strategy is required to address the several options that exist for the development and application of 2020 mining technology. Key issues in implementing 2020 mining technology will also relate to human resources, in terms of employment, skills and education. A need exists to proactively prepare for 2020 through development of a comprehensive education and training strategy.

Jan 1, 1998

By John Postle, Maureen Jensen, Marcel Vallee, Bernie Haystead, Dan Hora, Graham Clow

The Committee's proposed standards establish definitions and guidelines for the reporting of Exploration Information, Mineral Resources and Mineral Reserves in Canada and are identified as the "CIM Standards" and referred to as such hereafter in this document. To provide additional clarification to Qualified Persons (QPs), guidelines have been included with the respective definitions. The CIM Standards are applicable to all minerals including industrial minerals, diamonds and other gemstones. Reserve definitions for bitumen, natural gas and oil are not included in these Standards. The CIM Standards are not intended to cover mineral inventory estimates that will be reported to government agencies.

Jan 1, 2001

By J. Drenda

The model for methane removal from the workings directly behind an advancing longwall as presented in this paper may be used for U-ventilated cross or length-wise systems of longwall advance, starting from the boundaries of the extraction field. In mines with high methane concentrations, Uventilated longwall extraction from the boundary of the extraction field produces a methane risk. The risk is manifested by a higher methane concentration at the end of the longwall, upper gate and incline. The methane in increasing concentrations, which is emitted mainly from the workings with caved areas, appears towards the end of the longwall and in the upper gate. The graphical model of the longwall provided includes both the workspace of the longwall and the caved area. Based upon a model of the rock distribution in the cave, a ventilation model comprising two standard air splits and large number of crosswise air splits has been constructed. Simulations indicate that if the shearer is not present in the longwall, the air distribution in the caved area is symmetrical. The presence of the shearer, both at the bottom and the top of the longwall, causes an asymmetrical air distribution in the cave, that is the asymmetrical flows in the goaf and longwall workspace and in the inflows and outflow between those regions. This phenomenon causes an increase in methane concentration at the end of the wall and at the upper gate. The methane removal method proposed for workings with a caved area directly behind the advancing U-ventilated longwall, starting from the boundary of the field, consists of the removal of methane-air mixtures from the caved area with the boom pipes. These booms may be of several meters long and may be extended if necessary. The insertion of the boom pipes into the cave towards the end of the longwall and connecting them with the general methane removal system creates negative pressure causing a change in the depression field, which is the aerodynamic potential field in the goaf area around the ends of the boom pipes. This will promote the extraction of the methane-air mixture from voids and the goaf cracks, and the area from which methane is being extracted may extend to the side of the cave. This is a positive phenomenon, which could result in the methane flow from the goaf into the airflow in the longwall workspace decreasing or even stopping. A reduction in the methane flow into the longwall workspace with extractions booms will be advantageous for the production continuity. Based on the floor load model for the rocks in the cave and the methane-removal boom load model, the value of the force required to move the boom behind the advancing wall has been calculated. Strength calculations for the pipe were performed using a finite elements method. The analysis results, as well as the comparison of the pipe material effort to the strength parameters of steel, which can serve as piping material (for the assumed load conditions), lead to a belief that the proposed boom construction satisfies the strength requirements.

Aug 1, 2013

By A. J. MacEachen

"LIKE ALL OTHER NOVA SCOTIANS, I have been thrilled during the past few years with the growing evidence that substantial reserves of oil and gas are being discovered off the Atlantic coast of Canada. There are those in this province who believe that large-scale commercial production is just around the corner, and that when it starts Nova Scotia will begin to float on a sea of royalties. These overly optimistic people, of whom I am not one, are convinced that with the first barrel of oil shipped to market, Nova Scotia can forget its financial problems while its people take on the luxurious lifestyle of the shieks of Kuwait or Saudi Arabia. You and I know, however, that even though offshore oil and gas may turn out to be the greatest gift nature has ever bestowed on Eastern Canada, it may take some considerable time before the reserves can be accurately assessed, before the industry can become fully operational, and before the benefits of production can be translated into royalties and tax revenue, improved public services, new industrial facilities and more jobs. While it is premature for the ordinary Nova Scotian to take on the habit of buying expensive cigars and lighting them with ten-dollar bills, it is not too early for him to insist that governments and industry plan intensively and well for the beneficial exploitation of undersea resources."

Jan 1, 1973

By Grant J. Goddard

"The Iron Ore Company of Canada (IOC) has been in operation for over 30 years. Today, and in the future, technology and its application will play an ever more critical role in the company’s business success.The Carol Mining and Concentrating (CMC) division of IOC is energetically applying technology today to enhance performance and results, and is aggressively exploring opportunities to apply technology to support improved business results in the future.A critical area of focus is the application of technology to maintenance management performance. CMC has taken a “back to basics” approach to the fundamentals of maintenance management in 1995 and 1996. In parallel, the mine is aggressively implementing its Vision 2000 maintenance integration plan. This plan is targeted at levering the energies applied to sound maintenance management fundamentals as the company moves to a fully condition based maintenance approach.This paper discusses some of the strategies, key technologies and objectives of theVision 2000 maintenance integration plan at the mining operations of IOC."

Jan 1, 1996

"The Pierre Beauchemin Mine attained commercial production in January 1989, and went on to produce 23 968 ounces of gold for the year, 3% higher than forecast. Underground development was accelerated to prepare the way for the production of an estimated 40 000 ounces in 1989.IntroductionThe Pierre Beauchemin Mine is located nine miles west of the city of Rouyn-Noranda (Fig. I).As a result of the amalgamation with Sullivan Mines in October 1987, the mine is now entirely owned by Cambior Inc.The Eldrich deposit was discovered in 1953and began production in 1955, closing in 1962 following the decrease in gold prices and the simultaneous decrease in silica content in the ore, which was sold to the Noranda smelter for flux. A total of 717 000 tons grading 0.14 oz Au/t were produced during this period.From July 1984 to October 1987, an underground exploration program was carried out by Sullivan on the Eldrich mining concession and the nearby Flavel property. The first phase of the program included reinstallation of surface facilities and dewatering of the Eldrich Mine. Following the completion of the first phase, extensive exploration was carried out, including a major program of diamond drilling. It was then decided to deepen the shaft to a depth of 1800 ft to access a new zone called the No.5 Zone .Following the amalgamation with Sullivan in October 1987, Cambior assumed the role of operator for the project, and continued the shaft deepening work that had already been started. A feasibility study was completed in April 1988 and the Cambior board of directors approved a production decision for the Eldrich-Flavel project.The preproduction program extended from May to December 1988 and was aimed at preparing the stopes in the upper part of the mine and at developing the mine infrastructure at the bottom of the mine.The mine was officially opened in August 1988. Cambior renamed the project the Pierre Beauchemin Mine in recognition of Pierre Beauchemin's pioneer-work."

Jan 1, 1990

By W. Petruk, D. R. Morris

"The lead concentrate produced from the volcanogenic base metal ore of Brunswick Mining and Smelting in New Brunswick contains major to trace amounts of iron, zinc, cadmium, arsenic, antimony, copper, silver, selenium, tellurium, bismuth, sulphur, tin, indium, mercury and manganese as impurities. When the concentrate is sintered some of these impurities enter a variety of oxide phases, whereas others precipitate as metals. In the lead blast furnace the oxide phases decompose and the impurities recombine 10 form new phases, most are eventually discharged to the slag. The metals of the sinter remain as metals in the lead blast furnace where even more are produced, and are discharged largely with the lead bullion,IntroductionMany lead concentrates are produced from volcanogenic base metal ores . Such ores contain a wide variety of trace minerals and trace elements , therefore, concentrate s obtained from them will contain the trace elements as impurities . The impurities in the lead concentrate from one such ore, the Brunswick No. 12 deposit of Brunswick Mining and Smelting Corporation (BM S) in the Bathurst area in New Brunswick , were studied as pan of a larger investigation that was conducted to determine the extent of chemical reactions of the sinter within the lead blast furnace(1,2) The lead concentrate was investigated to identify the host mineral s for the impurities, the lead sinter was studied to identify the host phases, and frozen products from different depths within the BMS blast furnace at Belledune, New Brunswick were studied to determine the behaviour of the impurities.T he investigation was performed by pre pa ring polished sections o f the samples and studying them with a reflecting microscope, a scanning electron microscope (SE M) equipped with a Kevex energy dispersive X-ra y analysis system, a microprobe, and a Quantimet 720 image analyzer. The samples were also analyzed by X-ray diffractometer, and individual grains were analyzed by the Debye-Scherrer X-ray powder film method."

Jan 1, 1985

By Seungwoo Park, Whuisu Shim, Roe-Hoan Yoon, Kaiwu Huang

"A comprehensive froth model has been derived from first principles. It is based on predicting the kinetics of film thinning in the presence of particles of varying sizes and surface hydrophobicity. According to the Reynolds lubrication theory, the thinning of a horizontal film is driven by the excess film pressure (p), which is determined by the capillary pressure (pc) and the disjoining pressure (II). In the presence of particles, macroscopic capillary pressure (pc) is affected by the local capillary pressure (pc,local) in the vicinity of a particle and the number of particles in the film (N1,film), which in turn vary with the hydrophobicity and size of the particles. The Reynolds equation corrected for pc,local and N1,film is then used to predict the time (or froth height) at which a film is thinned to a critical rupture thickness (hcr), which in turn can be predicted using the Vrij’s capillary wave model (1966) after a modification to incorporate the contributions from hydrophobic disjoining pressure (IIhp). The model can predict bubble coarsening represented by the bubble size ratio between the top (d2,t) and bottom (d2,b) of a froth as functions of particle size and hydrophobicity, ? -potentials, frother dosages, froth height, gas flow rate, salt concentration, etc. The model predictions have been verified in experiments.INTRODUCTIONFroth flotation is regarded the best available technology today for upgrading minerals and coal fines. In the pulp phase of a flotation cell, air bubbles collect hydrophobic particles dispersed in it and rise to enter the froth phase on the top. Once in a froth phase, the bubbles coalesce with each other and become larger, resulting in a decreased bubble surface area. Under conditions of limited surface area, less hydrophobic particles drop off the bubble surface and return to the pulp phase. Thus, bubble coarsening provides a useful mechanism of increasing product grades. On the other hand, uncontrolled coarsening results in a decrease in bubble carrying capacity and hence throughput."

Jan 1, 2016

By Adam Jordens

Along with gravity separation and froth flotation, magnetic separation is one of the most common techniques for separating minerals. Minerals are separated by a magnetic force that is dependent on a combination of the applied magnetic field, the magnetic field gradient and the magnetic properties of the minerals themselves. Minerals may be classified as diamagnetic, paramagnetic or ferromagnetic based on the way they interact in a magnetic field. The magnetic susceptibility of a material may be determined by using a vibrating sample magnetometer to determine the magnetic moment of the material in an applied magnetic field and then converting this measured moment into the material?s magnetic susceptibility. In the case of rare earth minerals, magnetic separation is commonly used to remove ferromagnetic iron-bearing gangue minerals and to concentrate paramagnetic valuable minerals such as monazite and xenotime. These magnetic separation steps are frequently preceded by a gravity separation step as many iron oxides and rare earth minerals have specific gravities that are much larger than those of typical gangue minerals. By varying the magnetic field intensity it may be possible to use magnetic separation to selectively separate the paramagnetic and ferromagnetic minerals that report to the concentrate after gravity separation. Test work on a Canadian rare earth ore has shown that a gravity concentration step using a Knelson concentrator was able to selectively concentrate heavy magnetic minerals as evidenced by increased recoveries, relative to the Knelson tailings and fresh feed, after processing through a wet variable intensity magnetic separator. Mass pull to the Knelson concentrate was 4.5 % and the magnetic recovery of this concentrate, at 0.94 T, was approximately 40 % higher than the magnetic recovery from the Knelson tailings (70 % versus 30 %). The products of the wet high intensity magnetic separation were also analysed using a vibrating sample magnetometer to determine the magnetic susceptibilities of the various concentrate and tailings products.

Aug 1, 2013

By Farzad Mohammadi, David Kratochvil, Patrick Littlejohn

"With more rigorous regulations being enacted in the mining industry, a need exists for cost effective and environmentally compliant technologies to remove selenium from mine impacted waters to ultra-low concentrations. Existing selenium treatment methods have high life cycle costs, introduce risks of acute fish toxicity, and produce biological waste residues that represent future liabilities. Furthermore, achieving selenium discharge limits of less than 4 ppb is a challenge for existing technologies. Selen-IX™ is a technology developed by BioteQ that selectively removes selenium from mine impacted waters to less than 1 ppb. The technology is purely physico-chemical and takes advantage of the basic principles of ion exchange and electrochemistry. Unlike conventional electrocoagulation that removes suspended solids and breaks emulsions or oxidizes heavy metals, the electrochemical process employed by Selen-IX™ relies on creating conditions where iron acts as a highly effective reducing reagent transforming selenium from a dissolved species into elemental selenium bound in a solid phase. The iron-selenium by-product of Selen-IX™ is an inorganic, non-hazardous and chemically stable solid. Due to their high iron content, the solids produced by Selen-IX™ are of interest to the steel making industry as a low cost feedstock. This offtake potential can not only reduce the life cycle cost of selenium removal by reducing disposal costs but more importantly, eliminate the risk of future environmental liabilities. In this paper, the basics of Selen-IX™ technology are presented along with results of successful piloting on streams from coal and copper-gold deposits.INTRODUCTIONVarious contaminants are released into mining wastewater during the extraction and processing of metals. One such contaminant is selenium. A naturally occurring element found in rocks and minerals, mining activities accelerate its release into the environment. Selenium in trace quantities is essential to all life forms but at higher concentrations it can be harmful, especially to aquatic life where selenium bioaccumulation can lead to reproductive deficiencies."

Jan 1, 2016

By S. Dessureault

The relatively recent explosion of available data in all business sectors has induced a common expression of “drowning in data, starving for information.” The mining sector is affected by the information age through equipment-based sensors, process monitoring, and traditional enterprise data sources. Information technologists have developed techniques such as data mining that apply new and old statistical algorithms to large datasets. Mine planners and managers can apply these tools for improved planning and control, thereby increasing the use of the highly underutilized information system infrastructure in most modern mines. This paper describes the use of data mining and its enabling technology, data warehousing, in the development of an energy consumption model for large surface mines using real historical data.

Jan 1, 2007

By D. Berkley

"Economic and environmental constraints drive more and more industrial organizations in using energy management as one of the means for addressing these issues. The recent increase in energy price could even make energy management a matter of “survival” in some cases.Experience shows that energy management is successful when the energy is managed like a resource, i.e. continuously, systematically, and in an organized manner, not like an expense, paying the bills once a month. This requires the development and implementation of an energy management program (EMP).This paper outlines some of the barriers, keys to success, components, and approaches to a successful energy management program, plant- or corporation-wide."

Jan 1, 2005

By Lin Li, Ahmad Ghahremaninezhad

"In this paper, the electrochemical behavior of ferric and ferrous couple on the pyrite surface was studied by application of the chronoamperometry technique in an acidic solution at room temperatures and atmospheric pressure. The effects of the pyrite origin, ferric and ferrous ions concentration on the electron transfer kinetics of Fe3+/Fe2+ reaction were probed. Tafel behavior of all the test conditions were developed. The results showed that the ferric-ferrous reaction on pyrite electrodes with different origins have a common mechanism, despite different reaction kinetics. The exchange current densities of the redox reaction have the same magnitude of about 10-5 A·cm-2, which is far lower than the value reported for the gold and platinum electrodes, but larger than that of the chalcopyrite electrode. The cathodic transfer coefficients are between 0.4 and 0.5, while the anodic transfer coefficients appear unusual with the lowest value being 0.23. It was also demonstrated that an increase of one order of magnitude of iron concentration has no clear effect on the exchange current density and cathodic transfer coefficients of Fe3+/Fe2+ redox reaction.INTRODUCTIONPyrite, FeS2, is mostly considered as a gangue mineral which frequently coexists with valuable minerals and metals, such as gold, copper and nickel. Its separation from valuable minerals can be a costly process (Chandra & Gerson, 2010). In refractory gold ores, the fine gold particles are locked inside the pyrite structure. Oxidative leaching of pyrite is a hydrometallurgical method to destroy the structure of pyrite and expose the fine gold particles to the cyanide solution in the downstream cyanidation circuit. Pyrite oxidative leaching can be achieved by oxidation of pyrite via oxygen and ferric ion(McKibben & Barnes, 1986). In fact, pyrite oxidation by oxygen and ferric is a significant source of acid mine drainage(AMD), which adversely causes serious environmental problems(V. P. Evangelou, 1995).The pyrite oxidation mechanism is accomplished in three consecutive steps: (i) pyrite is oxidized by oxygen and ferrous ion formation (Eq. 1); (ii) ferrous oxidation by oxygen and ferric ion formation (Eq. 2); (iii) pyrite oxidation by means of ferric ions (Eq. 3). Hence, both oxygen and ferric participate in the pyrite oxidation process (Moses & Herman, 1991):"

Jan 1, 2016

By F. Hosseini

Shaping of metals by thixoforming relies on the unusual flow behavior of semisolid slurries containing nondendritic solid phase. The Flow behavior of metallic alloys containing both solid and liquid phases is investigated in the low solid fraction range (, 55%). This behavior depends on both the solid fraction and the shear rate. Four different shear rates is applied using back extrusion technique and flow stress versus true strain in different solid fraction is compared. It is well accepted that the flow stress s of alloys in their semi-solid state obeys to a thixotropic behavior, due to agglomeration and dissagglomeration phenomena during forming. The load-displacement curves produced from the tests may show an initial peak, believed to originate from a skeletal structure which rapidly breaks down under shear. Apparent viscosity obtained from this method is compared with other works and the proper power law of pseudo plastic state is introduced.

Oct 1, 2011

By Walter K. (Cory) Conrad

Two pumping tests in the Chilson Member of the lower Lakota Formation were completed at nearly the same location in 1979 and 2008. The 1979 test consisted of a pumping well and several surrounding observation wells penetrating the full 55-m thickness of the aquifer. The 2008 test consisted of a pumping well and three surrounding observation wells screened over 10 m in one of the known uranium ore horizons in the lower portion of the Lakota penetrated only about 3 meters of the more than 55-m thick lower Lakota aquifer. The average transmissivity and storativity values determined from the 1979 tests were 17.6 m2/day and 1.8 x 10-4, respectively. Comparing median transmissivity of 13.9 m2/day and storativity of 1.2 x 10-4 determined in the 2008 test to the 1979 test, the new aquifer parameters for the lower Lakota are respectively about 80 and 70 percent of the 1979 results. Because transmissivity and storativity depend on aquifer thickness, comparing the results suggests that there may be some scaling effect between the tests due to the differing lengths of screened intervals. However, the effect cannot be predicted by calculations such as relative screen lengths or open intervals to the formation, or sandstone versus shale thicknesses on geophysical logs. The scaling effect is attributed to partial disconnection between the lower and upper portions of the Lakota Formation aquifer by locally continuous shale interbeds. Suggestions to resolve this scaling issue are presented.

Aug 1, 2010

By S. Kelebek

Efficient separation of minerals is the essence of mineral processing. Separation of hexagonal pyrrhotite in processing of Ni-Cu sulphide ores was investigated together with particle size effects with respect to selective flotation recovery of pentlandite and nickel. The recovery by size response was compared for sodium metabisulphite (SMBS), triethylenetetramine (TETA) and their combinations with amyl xanthate as a collector. The pyrrhotite recovery for all sizes was lower than that of pentlandite for the blank case as well as individual cases with SMBS and TETA. For pyrrhotite, the recovery by size relations in the case of individual uses of reagents were mainly determined by recovery losses at coarser size range (>74 um), which occurs at a coarser size for pentlandite (>212 um). The combined use of SMBS and TETA, and the associated synergistic effect very significantly knocked down the pyrrhotite recovery to less than 7% that was a maximum for the –10 um (attributable to hydraulic entrainment). High recovery of pentlandite in a wide range of intermediate sizes and drastically low recovery of pyrrhotite resulted in a very efficient separation of pentlandite from pyrrhotite in all sizes. Separation of this mineral is discussed in relation to fundamental functionality of the reagents used.

Jan 1, 2017