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By Richard J. Kolada, Ian R. Muirhead

"This paper reports on a CANMET-funded examination of less conventional underground coal mining methods. These methods are documented and those that show the most promise for application to western Canadian conditions are discussed in detail.IntroductionIn recent years, mining considerations and economics have encouraged a transition from underground mining to surface mining. However, a change in market conditions or the development of superior underground mining methods may reverse this trend . Should this happen, the industry must be quick to respond and have information available on the latest developments of underground mining technology. In time, deposits of high-quality coal, which are easily accessible to surface mining, will be depleted and a change to underground mining methods will require consideration. The economic transition point between surface to underground will be a major determinant in maintaining a competitive edge. For these reasons, it is important to keep abreast of improvements in underground mining methods. To meet this objective, CANMET awarded a research contract to Monenco Consultants Limited, to investigate unconventional underground mining methods that show a potential for western Canadaoi. This paper presents the results of this investigation."

Jan 1, 1988

By Alfred W. G. Wilson

In this paper is presented a review of the changes that have taken place in certain Canadian non-metallic mineral industries since 1909. The fifteen-year period 1909 to 1923, inclusive, has been selected for two reasons. In the first place, statistical treatment of the subject under review has been nearly uniform throughout the period. In the second place, this decade and a half is itself further subdivisible into three well marked quinquennial periods, the middle one covering the period of the great war when industrial conditions were greatly disturbed. It then becomes possible to institute certain comparisons between equal periods before and after the war disturbances. The items selected for inclusion in this review are certain of the more important members of that class of minerals usually grouped together under the heading of non-metallics. They are all minerals of which Canada is known to possess important resources, and which are indispensable to many of our greatest manufacturing industries.

Jan 1, 1925

By W. Curlook, V. G. Papangelakis, M. Baghalha

A pressure acid leaching process has been developed for the extraction of metal values, nickel, copper, cobalt and zinc, from base metal smelter slags. The basic concept contemplates cooling the smelter slags through solidification sufficiently slowly to induce a good measure of crystallization; and subsequently, after fine grinding, to pressure leach such slags at around 250°C while applying oxygen overpressure, utilizing smelter byproduct sulphuric acid. High levels of extraction of the slags' metal values are thereby achieved. It has been shown that if the same slags are quenched thereby producing an amorphous structure, the resulting metal extractions are very low. The process is applicable to smelting furnace throwaway/discard/dump slags, as well as to in-process converter slags. By extracting the bulk of the residual base metal values in the throwaway/discard/dump slags, the resulting leached residues are rendered virtually benign vis-à-vis the external environment.

Jan 1, 2004

By S. S. Sephton, Kirit C. Vyas, Melvin J. Greaves

Energy requirements for various pelletizing systems are considered from a fuel and power aspect, with the presentation of typical energy heat balance flow sheets. A partial calculation for the firing zone of a straight grate system is shown and a comparison of an actual measured and a theoretical-calculated heat balance for a grate-kiln is presented. The power used for each pelletizing system and future possible energy savings a1•e also reviewed.

Jan 1, 1976

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 Bird. M.

As the Cadia mill was the first 40ft diameter SAG mill, commissioned in 1998, its performance, liner and discharge design attracted considerable international attention. Twelve years on, the liner design and the control philosophy are being readdressed to further improve the mill?s performance. A comprehensive series of 3D liner scans, over life of the liner, have been used to calibrate liner mass loss and progressive changes in the liner profile. This data is being used to provide true charge mass and mill filling, plus progressive trajectory profiles over life of liner. This information, along with measures of mill performance over liner life, is being used to select the optimal operating conditions as the liner wears, and hopes to inform future liner design.

Jan 1, 2012

By J. B. Boisvert, W. Board, C. R. Mooney

"Traditional geostatistical modelling methods are difficult to apply to heavy-tailed deposits because the extreme positive skew of the grade distribution leads to bias. The focus here is on an innovative method of modelling the high-grade population by conditionally simulating discrete volumes (nuggets) of gold with marked Poisson and Cox processes. Capping and other ad-hoc manipulation of the assay data is not required; however, an intensity map for the point processes is required. The method is demonstrated on a dataset from an epithermal deposit and demonstrates an improvement in reducing smearing and controlling the skew of the grade distribution.RÉSUMÉ Les méthodes traditionnelles de modélisation géostatistique sont difficiles à appliquer dans des gisements dont la distribution de la teneur est à queue lourde car l’extrême asymétrie positive de la distribution de la teneur génère des biais. Dans le présent article, l’accent est mis sur une méthode novatrice de modélisation de la population à haute teneur par la simulation conditionnelle des volumes discrets d’or (pépites) au moyen de procédés marqués de Poisson et de Cox. La limite d’utilisation et d’autres manipulations ad hoc des données ne sont pas requises; toutefois, il faut une carte des intensités pour le processus ponctuel. La méthode est démontrée sur un ensemble de données d’essais provenant d’un gisement épithermal et elle montre une amélioration dans le lissage du flou et dans le contrôle de l’asymétrie de la distribution de la teneur."

Jan 1, 2015

By C. L. Reichardt

"Pressure exerted on gold producers by regulators, project financiers, and civil society in the wake of the Baia Mare tailings spill in Romania during 2000 prompted most responsible gold companies to sign up to the International Cyanide Management Code for the Manufacture, Transport, and Use of Cyanide in the Production of Gold (the Code). The Code stipulates a ‘cradle to grave’ approach more comprehensive than that applied to any other mining reagent and poses particular challenges for operators who use cyanide-bearing tailings for backfill. This paper examine some of the challenges for Code compliance facing deep underground gold mines that employ backfill technology, most particularly the requirement to demonstrate that the potential migration of cyanide (and its degradation products) from emplaced backfill will not have an unacceptable impact on worker health and safety or on the receiving environment, either during mine life or after closure.Although the Code only contains a single reference to backfill, more careful consideration confirms that most sections of the Code that deal with tailings management are potentially applicable to mines where tailings material is used for backfill. Certain principles of the Code also pertain to aspects of operations, worker safety, emergency response, training, and dialogue with stakeholders relating to backfilling practice.For gold mines of the Far West Rand, the most significant cyanide-related risks associated with backfill operations relate to worker exposure to cyanide-bearing seepage and HCN gas. There is potential for seepage of cyanide-bearing water from backfill to compromise the beneficial use of surface and groundwater, and thus impact on downstream users and ecosystems. However, the extreme depth of mining and the specific geological and hydrological controls on the Far West Rand suggest that the potential environmental risks associated with backfill are likely to be considerably less significant than the cyanide-related risks to the workforce."

Jan 1, 2007

By N. Novikov, M. Jastrzebski, N. Kryzhanovskaya, D. Shevchenko, I. Kapran, N. V. Novikov, T. Koehler, B. Zaporozhets

"The PFK FeNi Smelter was re-commissioned by Solway Resources in 2002, ending a long period of economic decline in the adjacent town. In 2009 Hatch was retained to design, supply and install a custom furnace crucible that would accommodate a capacity increase from 34 MW to 40 MW and increase campaign life through binding and cooling technologies, as part of ongoing improvement efforts. The involvement of PFK personnel was critical to the successful integration of the new furnace technology with the existing process and operational practice. The furnace upgrade project was completed in 18 months during 2010 – 2011. Since start-up, the furnace has exceeded production expectations, operating successfully at 42 MW.INTRODUCTIONAfter ceasing operations in the 1990’s, the Pobuzhsky Ferronickel Combine (PFK), located in central Ukraine, was stripped of useful equipment and deteriorated while dormant. The surrounding town experienced a period of economic decline throughout the 1990’s. Solway Industries purchased the complex in 2002 and began a systematic incremental program to re-commission the smelter using both local expertise and specialists from other parts of the former Soviet Union. This led to the re-birth of PFK as a successful toll-smelting complex, and a renaissance for the surrounding economy.As part of the continuing improvement program, PFK approached Hatch in 2009 to study the possibility of a capacity expansion from 34 MW to 40 MW. It was decided, based on the results of the study, to design and install a custom furnace crucible integrating the unique PFK FeNi process with modern Hatch furnace technology. This novel approach had many benefits, including: maximum re-use of existing furnace components (off-gas, feed equipment and transformers), minimal impact on upstream and downstream equipment and building structure, and the retention of a familiar operating regime. The latter was a key factor in the success of the project, as it allowed the extensive operating expertise of the PFK staff to remain highly relevant to the upgraded furnace. This led to minimized capital investment, a rapid start-up and no significant operational challenges switching over to the new equipment incorporating Hatch furnace technology."

Jan 1, 2012

By Yoginder P. Chugh

This paper discusses design of sprays systems for dust control around a continuous miner (CM) in about 4.2 m (14 ft.) high mining areas with about 1.0 m to 2.0 m (3-6 ft.) of out-of-seam dilution mining. The challenges included low air volumes and velocity at the end of the line curtain, dust produced from out-of-seam dilution rock being very fine with 50% of the particles less than 10 micron, poor capture of aerosol through scrubber suction inlets, dust escaping through the sides of the loading pan in mining high areas, overloading of dust-laden air in the wet-scrubber, and dust rollback toward workers. The challenges were resolved through CFD modeling of airflows; improved line curtain installation, redesign and varying the spatial locations of spray systems as compared to low mining height areas. Water sprays on CM is the primary engineering control for dust control in coal mining. In 2010, the authors developed several spray system concepts for dust control (Chugh, Patwardhan, Gurley, & Hirschi (2009), Chugh & Gurley (2009), Chugh 2012). These included increased contact time between dust particles and water droplets, improved potential for the dust aerosol to be sucked in through suction inlets, and reduced dust-roll back to the operators and workers. CFD modeling was used to understand airflow patterns around mining areas and to identify spatial locations for sprays to minimize dust exposure of CM operator (CMO), haulage unit operator (HUO), and workers downwind of the operating CM in the last open crosscut (LOXC). Face area ventilation plays a key role in dilution and removal of dust generated by mining operations. High mining heights and large pillar sizes associated with longwall mining reduce the air volume reaching the face area to achieve good dust dilution.

Aug 1, 2013

By Jacque Trottier, Marcel Vallée, Gratien Gélinas

"Mineral exploration in Canada traditionally has gone from boom to bust in cyclical pat-terns following market and discovery cycles, but other endemic factors related to exploration financing and performance have contributed to the amplitude and recurrence of these fluctuations. In view of these problems, junior exploration is reviewed here in a marketing perspective, looking at the 4 Ps: Product, Price, Placement and Promotion.In the 1980s, MEDA incentives gave the shares of junior and mining companies significant price and promotion advantages, and contributed to excessive exploration funding. Many were thus led to minimize the basic values needed for continued investor interest: appropriate levels of product quality, sustained share value and customer satisfaction. Basic changes are needed to improve the marketing of junior mineral exploration in the future, with or without improved fiscal incentives. To be successful, the required improvements must come from the technical participants, but the financial partners also need to be involved.Exploration in Canada must be marketed with vigour, both in Canada and internationally. Exploration, mine development and mine production are essential to our economy. They are environmentally acceptable and they are welcome in Quebec and in most Canadian provinces and territories. Canadian exploration and mining are entrepreneurial industries that must take better advantage of their strengths and achievements and remove the shortcomings that hinder them: nobody can do it for them!"

Jan 1, 1996

By B. Surender Mohan

Mining lignite pollutes the environment and causes ecological damage if unattended. Being conscious of the importance of environmental resources for the well-being of the living system, the Neyveli Lignite Corporation (NLC) adopts the policy of environmental regeneration as the foundation on which productivity is built. NLC started investing on Eco Care and Environment Protection long ago and it continues. Early investment in environmental protection has resulted in steady growth of the Company along with a healthy environment. The future vision of NLC is to be in the vanguard among the contributors to the community, environment and the nation by developing and utilizing industrial and human resources to the optimum. Untiring efforts are being put in mines (NLC as a whole) to maintain and sustain the ecological balance arising due to continuous mining activity. NLC?s Environmental Management System is becoming a symbolic role model for many of the opencast mines in Southeast Asia. NLC has been bestowed with number of prestigious Environment and Sustainability awards in recognition of the mammoth contribution in maintaining a clean and green environment.

Aug 1, 2013

By S. L. Gertsman

Canadian steel foundry practice has made marked progress during the past decade. Equipment suppliers, development engineers, and foundry personnel have focussed their attention on every phase of the foundry operation, with a resulting lower demand on manpower and materials. Also, more rigid specification requirements as to dimensional tolerances and quality have necessitated improvement and increased control at every stage from the pattern shop to the cleaning room. The growing trend toward mechanization is clearly evident. Equipment such as sand mixers, sand reclamation systems, material handling devices, moulding machines, core blowers, etc., is being increasingly employed by the steel foundryman. This equipment not only increases production but also tends to lessen the human variable so prevalent and disconcerting in the early days of steel founding. The result has been an improved and more reliable steel casting, which is gradually obtaining wider acceptance by design engineers. The purpose of this paper is to discuss briefly some of the practices being used, and also the direction of development that is being pursued by Canadian steel foundrymen.

Jan 1, 1948

By J. Budac, E. Krause, C. L. Stewart, D. Wrana, S. W. Laundry

"As part of an over-all arsenic management strategy, Inco has developed a novel process that converts a by-product high moisture copper/arsenic sulphide precipitate into a crystalline copper arsenate suitable for the manufacture of wood preservation chemicals.The copper/arsenic sulphide precipitate is atmospherically leached with oxygen and sulphuric acid, producing a crude (blue) copper arsenate precipitate, elemental sulphur, and a copper and nickel containing solution. The blue copper arsenate is dissolved with sulphuric acid, the molar Cu/As ratio is raised to 2, and a crystalline copper arsenate (olivenite) is precipitated by the addition of sodium carbonate. Dissolved copper is recovered using metallic nickel (or matte) and elemental sulphur, to produce a low-moisture (low-arsenic) precipitate suitable for standard nickel-copper processing.The process was successfully piloted at Inco's Manitoba Division between September 1990 and June 1991. The copper arsenate product typically analyzed 43% Cu and 25% As, and the moisture content was about 10%."

Jan 1, 1995

By Jay Tuttle

THE spiral stoping method of mining was first seen by the writer at the Granby Consolidated Mining, Smelting & Power Company's Hidden Creek mine, at Anyox, British Columbia. Where the method received its name, or by whom it was named, is a question, but it was employed by the Granby Company at their Phoenix mine, in the Boundary district, B.C., as early as 1901-02 after they had tried unsuccessfully other methods at that large, law-grade property. its adoption there was suggested by two miners, John and Steve Swanson, then working at Phoenix, who had previously been employed in the hard iron-ore mines of Michigan and Wisconsin, where they had learned this system of mining. The method proved successful at Phoenix and also, later, at the Company's Hidden Creek mine at Anyox, where some 40,000,000 tons, or more, of ore was mined in this manner during a period of about thirty-five years.

Jan 1, 1939

By M. Imani, A. Fahimifar, A. H. Javid

"Current studies of bearing capacity for shallow foundations tend to rely on the hypothesis of an isolated footing. In practice a footing is never isolated; it is mostly in interaction with other footings. This paper focuses on a numerical study to evaluate the ultimate bearing capacity for two interfering strip footings resting on a rock mass in which the strength can be described by the generalised Hoek–Brown failure criterion. This criterion is applicable to intact rock or heavily jointed rock masses that can be considered homogeneous and isotropic.The material is assumed to exhibit perfect plasticity and obeys an associated flow rule. The effects of Hoek–Brown parameters including GSI, mi, and sci were studied and the corresponding results are presented. For different clear spacing (S) between the footings, values of the efficiency factor (?) were determined; where ? is defined as the ratio of the failure load for an interfering new footing of a given width (B) to that of a single isolated footing having the same width. The maximum value of (?) occurs at spaced between S/B = 0.5 to 1.0. The results have been compared with those available in the literature.INTRODUCTIONEvaluating the ultimate bearing capacity of rock masses is essential for important projects like dams and bridges. Closely spaced footings may occur on rock masses in the form of pier foundation and grillage footing. Close spacing lead to permit higher loads than can be bore by similar isolated footings. The ultimate bearing capacity of two interfering strip footings resting on cohesionless soil have been studied theoretically (Kumar, & Gosh, 2007; Kumar, & Kouzer, 2008; Stuart, 1962). Results revealed when two strip footings approached closely enough, failure zones affect each other and ultimate bearing capacity significantly increased."

Jan 1, 2015

By J-L. Tang

A new rhcoforming processing of Al alloys with component shaping systems apart from slurry preparation systems is experimentally exploited, using the reversible multilevel-speed electromagnetic stirrer, the slurry transfer tool and its coating, the thin plate sample with five steps and rheocasting mould, all of which are independently developed. The results show that semi-solid A356 alloy slurry with shape factor of about 0.85 and particle size of 70~80 µm (under air-cooling condition) could be prepared in 20~25 s, fully meeting the production rate of high pressure die casting. The slurry could be smoothly transferred from the slurry preparation equipment to the rheocasting shot chamber while the slurry temperature of slurry decreases by no more than 3 . The tensile strength and elongation of the semi-solid rheocasting samples could be respectively increased by 11.6~18.2 % and 42.5~50 % compared with the traditional liquid die casting ones, and the rheoforming processing has close affinity with the traditional hot working processes.

Jan 1, 2007

By R. L. Dunsmore

Introduction If one had been called upon to describe petroleum oil refining seventy-five years ago, he could have acceded to the request quite satisfactorily in about fifteen minutes. Fifteen years ago, an hour and a half would have been sufficient to give a general idea of oil refining, and of the equipment used for this purpose. Today, so extensive has been the research into all phases of the refining and manufacturing of petroleum products, and so rapid the strides in improvement in technique and equipment, that I doubt if a week would suffice to give an adequate outline of ail the ramifications of present-day oil refining. I propose to only 'hit the high spots', dealing particularly with the equipment and methods employed at the Imperoyal refinery, which you are to visit. Crude oil, the refiner's raw material, contains essentially only two elements, hydrogen and carbon. These are not present in the free state but are combined in various proportions as 'hydrocarbons'. A given crude oil is not made up of just one hydrocarbon, but of myriads; some solid, others liquid, and still others gaseous at atmospheric temperature and pressure, ail dissolved one in the other. Moreover, the nature and the relative amounts of the several hydrocarbons vary very considerably in crude oils from different sources. That is, a 'crude' from Oklahoma will contain hydrocarbons not present in crude from Mexico, and is different again from the Venezuela crude. Not only this but oil in a certain well in, say, Peru may be differently constituted from that in a well half a mile distant from it.

Jan 1, 1931

By Junior Santos

Kinross Paracatu started the operation of the new gold processing plant in the end of 2008, being composed by one SAG mill and two ball mills. During the first year of operation the plant had several problems related to stability and throughput capacity, mainly due to low grinding efficiency of the ball mills. In this period many actions were taken to maximize the throughput rate. Among the actions are reducing the size of balls in the mills, increasing the ball charge in the SAG mill, changing cyclone configuration and return of circulating load to SAG mill. With better stability of the circuit, the second stage of improvements has begun with the objective of increasing throughput rate and also reducing operation costs. Among the actions are the optimization of ball charge in the mills and a better operational control of cyclone parts. After two years of operation was obtained a significant increase in plant capacity, but still requires the addition of a third ball mill in order to maximize the use of SAG mill, which has spare capacity.

Jan 1, 2012

By C. George Miller

"As the influence of governments has become more widely felt, the use of research techniques to analyze policy has increased. Mineral economics, as one of the foundations of mineral policy research, has grown accordingly. Policy research and analysis has been carried out within governments, university departments and the private sector. Each of these institutional environments has characteristics which influence the topics of study, the approach, the methodology and the output of the research. A brief survey of recent research activities provides illustrations of trends and developments occurring within this organizational framework.A radically different organization, the independent research institute, has begun to make an impact on policy research in recent years, and will have an increasing importance in the future. Combining certain features of the traditional research organizations, it nevertheless has important differences which are essential to its effective functioning. An overview of the formation, goals, organization and operation of one such institute is presented."

Jan 1, 1976