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By P. D. R. Maltby

"The Canadian Institute of Mining and Metallurgy has undertaken to host the XIV International Mineral Processing Congress to be held in Toronto at the Royal York Hotel from October 10 to 16, 1982. The theme of the Congress will be ""Worldwide Industrial Application of Mineral Processing Technology."" The program will include 10 sessions and numerous field trips to the different mining areas of Canada.For prospective authors, the preliminary program includes sessions on,1. Flotation - plant practice, equipment design, simulation, control and economics.2. Comminution - plant practice, equipment, design, simulation, control, wear, energy consideration and economics.3. Round table seminar on large grinding mills.4. Round table seminar on modern and future plant design.5. Mineral processes to recover precious metals.6. Mineral processes to recover energy minerals (coal, uranium).7. Mineral processes to recover industrial minerals.8. Round table seminar on the environment and ecology and how the different countries cope with associated problems.9. Materials handling with an emphasis on agglomeration techniques ereconentration methods, solid-liquid separation.10. Open session to deal with topic emerging from general demand."

Jan 1, 1980

By Gobbs C., J. Lam

"The Eagle East project, accessed from the existing and operating Eagle Mine in the Upper Peninsula of Michigan, is an underground base metal project currently in execution by Lundin. This paper will provide an update on several aspects of ventilation including use of a twin-decline access, innovative airflow crossover arrangement and construction ventilation methodology. Integration into existing mine ventilation systems including construction methodology will also be covered. Performance benchmarks and lessons learned are discussed across these topics.INTRODUCTIONLundin has owned and operated the Eagle Mine since 2013. This hard rock underground mine is located in the upper peninsula of Michigan, USA. High-grade nickel ore is mined using sublevel open stoping mining methods and trucked to surface via haul ramp. The mine, having been in production for four years, is nearing the completion of the initial orebody. A satellite orebody 2,000 meters East of the current workings and approximately 900 meters below surface, was identified that could extend operations until 2023. In 2016, Lundin approved the Eagle East project and construction began in 2017 (Lundin Mining Corporation, 2017).Due to proximity to the existing mine, Eagle East will be both accessed and serviced from the existing Eagle Mine. Ventilation at the Eagle Mine uses two fresh air intakes with direct fired combustion heaters; one at the mine portal feeding fresh air into the ramp and one at a fresh air raise located near the Eagle deposit. The primary ventilation circuit is powered on the exhaust air side, with two 700 hp exhaust fans located at a single return air raise. Underground, fresh air is distributed through the main access decline and fresh air raise (FAR) to the production levels and controlled with mechanical regulators on the exhaust side. The exhaust air is collected through return air raises with a collector/transfer drift on 250 Level and then to the surface through a return air raise (RAR)."

Jan 1, 2019

By S. Banisi, E. Arghavani, A. Akbari, Gh. A. Parsapour, S. Darvish Tafvizi

The new copper processing plant of the Sarcheshmeh copper complex consists of two parallel circuits. After a primary crushing, the ore is sent to a SAG mill and the product is further ground in a ball mill. The overflow of the hydrocyclones is fed to a flotation circuit which contains 8 rougher tank cells (RCS130), 3 cleaner cells (RCS50), 5 scavenger cells (RCS50) and a 4 x 12 m flotation column as recleaner. The circuit was initially designed to process a feed containing 0.8% Cu, but because of the ore type change, the feed grade decreased to 0.6% Cu. This resulted in a reduction of final concentrate grade and recovery from 28 and 85.5% to 24 and 84.4%, respectively. Based on the original design, the copper and silica recovery in the cleaner cells should be 69 and 55%, respectively, but these values increased to 85 and 75% because of a higher retention time. The rather high silica recovery (i.e., 75%) was found to be the main source of the lower final concentrate grade. In order to reduce the retention time of particles in the cleaner cell from 13.7 to 6.9 min, the rougher concentrates of two parallel circuits were fed to only one cleaner-scavenger and regrind circuit. This modification increased the cleaner and final concentrate grade from 15.1 and 24.5% to 17 and 26%, respectively. To prevent a possible reduction in the copper recovery, the froth depth in the scavenger cells was reduced. The overall outcome of the circuit modification was evaluated to be a 10% reduction in the energy consumption without any loss in the overall copper recovery.

Jan 1, 2016

By Robert S. Penczak

Red Lake Gold Deposits ? Descriptive Classification (modified from Pirie, 1982) VHR Au -- Volcanic-hosted (vein & wall-rock) replacement Au deposits ~93% of camp production Q-(T) Au -- Quartz-(tourmaline) vein Au deposits ~7% of camp production Quartz-sulphide Au deposits Porphyry-hosted sulphide Au deposits Current & Significant Past Producers Camp Production 21.6 M oz / 672 tonnes Au Other Deposits / Occurrences (Intermittent Exploration

Apr 1, 2005

By D. W. MacFarlane

In the formation of Oil and Gas Producing Units lawyer& and engineers are interdependent members of the same team. Management is, there-fore, entitled to expect no less than a total cooperative effort from the members of these professions. The petroleum and natural gas lawyer must diligently inform himself on the implications of engineering evidence. Otherwise he can be of little assistance to his engineering witness in a thorough, systematic and convincing presentation of his technical evidence. Conversely, the engineer must appreciate the concern of counsel that quasijudical hearings, whether technical or otherwise, be con-ducted in such a manner as to pre-serve some semblance of organized judicial procedures in the adjudication of property rights. The principal problems in unitization are the participation formula and the adjustment of investment in unit facilities. The equating of oil to gas, the effect of unit infill drilling, the relative values of producing zones and well productivity have •been controversial factors in several Saskatchewan units to date. Perhaps the most perplexing of these has been well productivity. While preserving current income, it may also preserve an ability to drain adjacent tracts plus an inequitable sharing of .reserves properly attributable to secondary recovery operations. However, inequity may also result in depriving an operator of the benefits accruing to him under competitive operations by virtue of his favourable reservoir position or his use of advanced production techniques. The Saskatchewan Oil and Gas Conservation Act has been construed by the Department of Mineral Resources as •completely negating any benefits inherent in the rule of capture when determining equities under unit operations. Under adjustment of investment provisions, large cash flows between owners of exploited acreage should be avoided upon the creation of a unit. These provisions should not deprive any company of the benefits it may have obtained under competitive operations in producing its fair share of the reservoir at a lower net cost per barrel than its competitors. Unitization should be concerned with physical conservation rather than in equalizing production costs as between operators.

Jan 1, 1960

By P. C. Benedict

"The Island Mountain mine is at the southeast end of Island mountain; across Jack of Clubs lake from the Cariboo Gold Quartz mine.; The orebodies consist of quartz veins and pyritic replacement deposits in limestone. To December 31; 1944; there has been mined 296; 273 tons of quartz-vein ore averaging about 0.34 oz. gold a ton; and 101; 002 tons of sulphide ore averaging about 0.83 oz. gold a ton; a total of 397; 275 tons averaging 0.46 oz. From this; 175; 985 fine oz. of gold and about 26; 450 fine oz. of silver were recovered; having a value of $6; 510; 521.More than 95 per cent of the production has come from a band 500 feet wide along the contact of the Rainbow and overlying Baker members and extending about 100 feet into the latter. Evidence that the Rainbow belongs stratigraphically above the Baker is presented later in this paper. Both members are most variable lithologically, and individual beds and whole series of beds pinch out in short distances. In part, at least, this is due to squeezing out incidentally to intense folding. No section can be claimed with assurance to be really representative. However, both memb.ers are composed predominantly of quartzitic rocks. Both contain argillaceous quartzite, argillite, limy quartzite, limy argillite, limestone (marble), and minor amounts of highly ankeritized rocks believed to be igneous sills possibly originally approaching diorite in composition."

Jan 1, 1954

By T. R. Ellis

The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned. Since 1981, the Securities and Exchange Commission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis. Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers.

Mar 1, 2002

By T. R. Ellis

"The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned.Since 1981, the Securities and ExchangeCommission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis.Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers."

Jan 1, 2002

By T. C. Cheng, G. P. Demopoulos

It is the object of this paper to discuss various options for improving the hematite process in terms of increased throughput hence lower capital cost and production of saleable quality hematite. With reference to increasing the throughput of the process, it has now been determined via the analysis of Akita Zinc Co's continuous industrial autoclave performance data that the process kinetics is limited by the rate of the hydrolytic precipitation reaction. By correlating the hydrolytic precipitation rate to supersaturation ratio, it is shown that accelerated kinetics can be achieved via the following measures: (1) in-situ neutralization with addition of zinc calcine; (2) elevation of temperature; and (3) dilution of feed; of which, the first one was retained for further evaluation. According to presented estimates, addition of calcine, amounting to only 2.6% of the total zinc calcine processed, can allow for shortening the retention time by at least 50%. Such drastic shortening of retention time may be either used to increase the throughput of a given autoclave circuit or alternatively to release autoclave capacity for clean hematite production. Hydrothermal treatment of the crude hematite product proved effective in producing clean hematite as according to laboratory tests, hence allowing the sulphur content of hematite to be reduced from around 4% to less than 1%. A conceptual flowsheet incorporating in-situ neutralization for accelerated kinetics with hydrothermal upgrading of crude hematite without sacrificing production capacity and with minimum upset of the plant's water balance is described.

Jan 1, 2004

"10.1. IntroductionAs discussed by Westland (1981), the six platinum-group elements (PGE) belong to the Group VIII transition metals, to which iron, nickel and cobalt also belong. The chemical similarity between these nine metals accounts for the fact that they tend to be concentrated together as a result of geological processes. These processes started to effect the distribution of these metals at the very beginning of the earth's history.The first line in Table 1 gives the concentration of nickel and certain other Group VIII transition metals in carbonaceous chondrites, those meteorites with a composition that is believed to reflect best the composition of our planetary system apart from hydrogen and helium. The second line is the estimated concentration of the same elements in the earth as a whole. It is seen that these two estimates are quite similar, the earth being perhaps 2 to 3 times richer in these particular metals than the planetary system as a whole. The reason for this is not fully understood, but it may be due to the earth being formed by the accumulation and capture of a greater proportion of iron (and therefore siderophile-rich) than stoney (and therefore siderophile-poor) planetesimals than the planetary system itself.The third line in Table 1 is the average composition of the crust of the earth. With the exception of iron, all of the Group VIII transition elements are rare in the crust, present at concentrations of It tOO to Itt ,000 of that of the bulk earth. This is because the outstanding chemical characteristic of this group of elements is their siderophile nature; that is, their tendency to alloy with metallic iron. Because of this, once the earth became molten very early in its life history, these elements dissolved in the molten iron present at this stage and were removed from the outer accessible parts as this dense liquid sank to the centre of the earth to form the core. Although iron was the main instrument of concentration of the Group VIII metals, its much greater over-all abundance and its ability to combine with oxygen more easily than the others in the group means that significant amounts still remain in the oxidized portions of the earth.The fact that most of the Group VIII metals are available to use in workable concentrations at all is that they are 5 to 30 times more concentrated in the earth's mantle than the crust, as shown in line 4 of Table I. There has been a constant, if slow, interchange of matter between the mantle and the overlying crust throughout most of the earth's history and, under certain circumstances, this interchange has given rise to economic concentrations of metals."

Jan 1, 1979

By Harry F. Weaver

WHEN 1 was assigned by the Director of the United States Bureau of Mines to present a paper at this annual meeting of the Mining Society of Nova Scotia, 1 was grateful, honoured, and elated to realize finally a life-long desire to see your beautiful land and visit with you who have the good fortune to live and work here. Naturally, in preparing for this important event, 1 wanted to give you something of special interest within the limits of the subject so I chose an area dose to my heart -the operation of our Federal coal mine inspection service, which has, as its fundamental purpose, the prevention of accidents in and around ?Coal mines. In 1957 the United States had 10,879 active coal mines scattered throughout 28 States and the Territory of Alaska. The production of coal for the year was about 515,472,000 tons, including 2.5,472,000 tons of anthracite and 490,000,000 tons of bituminous coal and Hgnite. Anthracite is mined principally in a comparatively small area of one State. AU the 28 States and the Territory produce bituminons coal and/or lignite. The beds mined range from 18 inches to more than 100 feet in thickness and from the horizontal to the perpendicular.

Jan 1, 1958

By A. A. Goss

We investigate the relationship between corporate financial performance (CFP) and environmental and social performance (CSP) in a sample (n=165) of large, publicly traded U.S. mining and oil and gas firms. Using optimally scaled principal components analysis to generate aggregate measures of CSP strengths and concerns, we find higher concerns are related to higher volatility of unexpected earnings and discount rates. Furthermore, these earnings shocks are more likely to be negative as concerns increase. Decomposing this relationship shows that negative environmental performance dominates proactive environmental management as a driver of unexpected earnings, but proactive community efforts increase the magnitude of earnings shocks. We document some evidence of the strategic use of CSR, with those firms that have greater risk investing more proactively in CSR.

Aug 1, 2013

By N. Geoffroy, E. Benguerel, G. P. Demopoulos

In the late 1990s, a chemical process to remove mercury and selenium from weak sulphuric acid solutions was patented and implemented in the CEZinc refinery in Valleyfield, Quebec. The CEZinc process comprises two stages. In the first one, sodium sulphide is added to the weak acid solution in order to precipitate the soluble mercury. The solution is then treated with sodium dithionite in order to reduce the selenium to elemental form. Because of recent changes in the composition of the industrial solution, a project to study the background chemical reactions was started. In this paper, a review of the background chemistry is presented on the basis of several eh-pH diagrams on one hand, while on the other experimental results are reported dealing with the reaction of selenium (IV) species with either dithionite, sulphide or a combination of the two. According to this work, elemental selenium enjoys a wide pH-eh range stability with selenium sulphide being metastable. Selenium (IV) in single metal synthetic solutions was found to be reduced - to elemental state - at ambient temperature down to ppb range with dithionite as long as the stoichiometric ratio (dithionite/selenium) was in excess of two and the pH < 1.7. Under these conditions the reaction was very fast reaching completion within one minute. Sodium sulphide proved equally effective in reducing selenium (this time as selenium sulphide) to ppb range from single metal solutions. However, in mixed Se-Hg solutions deviations from this "ideal" behaviour was observed resulting in higher levels of residual soluble selenium left in solution.

Jan 1, 2008

By R Thomson

The use of uranium metal in non-ferrous metallurgical practice is dis-cussed with reference to its alloying behaviour and chemical activity. It is suggested that the more promising applications are in the treatment of molten metals to combine with impurities. Mines Branch work along these lines is described for copper, zinc, magnesium, aluminum and nickel alloys. It is shown that a cop-per-uranium master alloy (25 per cent U) successfully deoxidizes molten copper without detriment to the electrical or mechanical properties of the product at residual uranium levels of up to 0.8 wt. per cent. Additions of uranium to alpha brass in amounts greater than the lead impurity content were found to remove the deleterious effect of lead on hot-workability. Similar deoxidizing and malleableizing effects were found with uranium additions to nickel. It is thought that uranium forms stable intermetallic compounds with many impurity elements. A significant malleableizing effect can therefore be expected in the presence of other elements besides lead.

Jan 1, 1963

By T. Liu, C. Shi, T. Fu, M. Zhong

Water inrush in coal mines is induced by the imbalance of the groundwater flow field and the engineering geo-mechanics field. Therefore, to prevent water inrush it is important to predict the critical hydraulic pressure of water inrush in coal seam floors. This paper will investigate a method for conducting theoretical forecasting of the critical hydraulic pressure of water inrush in coal seam floors by adopting the combination method of a genetic algorithm-neural network. First, the topology structure of a neural network (NN) based on genetic algorithms (GA) will be determined and then the critical pressure of water inrush in a coal seam floor using the chosen NN will be predicted. Finally, theoretical forecasting results will be compared with actual measurement results to determine the feasibility and applicability of this method.

Jan 1, 2008

By Yves Gratton

The International Commission on Large Dams (ICOLD) is a non-governmental International Organization which provides a forum for the exchange of knowledge and experience in dam engineering. It is the world&apos;s leading professional organization dedicated to advancing the technology of dam engineering and supporting socially and environmentally responsible development and management of the world&apos;s water resources. ICOLD was founded in 1928 and has National Committees in 82 countries with approximately 7,000 individual members who are engineers, geologists and scientists from governmental and private organizations, consulting firms universities, laboratories and construction companies. Its original aim was to encourage progession in planning, design, construction, operation and maintenance of large dams and associated civil works by collecting and disseminating relevant information and by studying related technical questions. Since the late sixties, focus was put on subjects of current concern such as dam safety, monitoring of performance, reanalysis of older dams and spillways, effects of ageing and environmental impacts. More recently, additional subjects have included cost studies at the planning and construction stages, harnessing international rivers, information for the public at large, and financing.

May 1, 2002

By Brian Rausch

Agenda ?? Refresher: Victor Project Execution ?? Operations Capability roadmap: ? Operations staffing starter group: design participation ? Operations staffing build up for production start-up ? Training and commissioning integration ? Turning OPSCAP ramp-up into a project ?? Go Live! The Results

May 1, 2009

By George Meadows

Consultation and Accommodation Introductions Consultation -Best Practices The Role of Negotiations The HVC Experience Summary / Conclusions The Challenge Meeting legal and policy obligations to consult while adhering to project priorities, timelines and budgets Defining who needs to be consulted, by whom, and ?how much?? Accommodation ?who is responsible and what is the appropriate scope? Social License -establishing positive working relationships with First Nations involved in project review / approvals / implementation in a manner that advances the interests of all parties

May 1, 2010

By W. D. Sinclair, R. J. Cathro, E. M. Jensen

"The Cash is one of the largest porphyry copper-molybdenum Deposits found in Yukon to date. It is 80 km northwest of Carmacks, within the unglaciated portion of the Dawson Range, and is associated with the Big Creek fault, an important tectonic feature. Part of the mineralized zone is blanketed by up to 70 m of alluvial drift . The remainder is covered by a relatively thin residual soil layer. The mineralized zone, however, was not detected by conventional stream-sediment sampling because pathfinder elements, such as Cu and Mo, have not been geochemically dispersed into the main drainage system. The deposit was discovered by a combination of soil analysis and inspection of rock fragments from small pits.Twenty widely spaced, shallow drill holes have outlined an areaover 2700 m long and 550 to over 1000m wide that grades more than 0.1% copper equivalent (% CuE = % Cu + (5 x % MoS2)). Two smaller zones grading over 0.4% copper equivalent occur within the larger area. The limits of the widest end of the deposit have not been delineated.The Cash deposit is fairly typical of high-level, calc-alkaline porphyry copper-molydenum occurrrences in the Canadian Cordillera {cf, CIM Special Volume 15) and is representative of most prospects in the Dawson Range. It is associated genetically with a subvolcanic complex of small, irregular stocks and dykes of feldspar porphyry and related breccias of Late Cretaceous age. Copper and molybdenum sulphides occur along fractures, in quartz veinlets and disseminated in feldspar porphyry and in older metasedimentary and intrusive rocks. Higher-grade zones of copper and molybdenum have associated potassic alteration. Phyllic alteration is, in part, superimposed on potassic alteration. Argillic alteration occurs locally.This paper describes the history of the discovery and the geochemical and geophysical characteristics, together .with the regional geology, and the nature and distribution of the host rocks, hypogene mineralization and hydrothermal alteration."

Jan 1, 1981

By Meimei Zhang

In the overall open pit mine planning process, mining phase design is a strategic driver in guiding and constructing the block extraction sequence and determining the annual net cash flow distribution. Mining phase design should obey some practical constraints, such as ?minimum mining width? and ?flat mining phase bottom?, to allow space for haul road development and truck and shovel access on each bench. However, these practical mining phase design requirements are not taken into account in all first-cut mining phase design methods and post-processing is always required to convert an impractical design to a practical one, resulting in a potentially significant loss of Net Present Value (NPV) relative to the first-cut impractical designs. In this paper, we present a method using a meta-heuristic algorithm ? Simulated Annealing ? to enforce those practical constraints in determining a mineable phase design whilst ensuring minimum NPV loss.

Oct 1, 2009