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By B. R. Neufeld, M. G. Heximer, S. J. Roach, W. G. Van Luven, D. G. Reynolds

"Teck Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. In the zinc plant, zinc concentrates are roasted to produce calcine, which is then processed in the leaching circuit for zinc recovery. Calcine is first dissolved at pH <2.0. This is followed by a precipitation stage using additional calcine that removes iron as a ferric hydroxide precipitate which is recycled to the lead operations. It is during this pH adjustment that impurities, notably arsenic, antimony and germanium, are co-precipitated with ferric hydroxide which is the primary removal phase for these elements. Recent processing conditions have resulted in lower iron inputs to the leaching circuit and this has resulted in insufficient co-precipitation of key impurities. This paper summarizes the influence of iron concentrations on impurity removal using laboratory and plant scale surveys, and emphasizes key specification limits for the primary iron removal circuit.INTRODUCTIONThe Sulphide Leach Plant (SLP) at Teck Metals Ltd., Trail Operations produces a zinc sulphate electrolyte from three different zinc bearing streams:1. Calcine, primarily containing zinc oxide, from the roasters2. Zinc electrolyte from the Oxide Leach Plant (OLP) is produced by leaching zinc oxide fume from the pyrometallurgical lead smelting operations3. Zinc slurry from the Zinc Pressure Leach (ZPL) autoclaveThe feed sources are blended and introduced to the iron removal process to precipitate iron in the form of a hydrolyzed iron precipitate which is recycled to the lead smelting operation. Along with iron, impurities, namely arsenic, antimony, germanium and silica, also co-precipitate; this process acts as the primary removal step for these elements. Following iron removal, the electrolyte is further processed in the zinc dust purification circuits. Cadmium and copper are removed in the cold stage circuit via zinc dust cementation, followed by cobalt cementation in the hot stage circuit."

Jan 1, 2016

By J. B. Sabey, V. R. Degner, D. MacGillivray

"Hydrodynamics principals are applied to the design of a natural air ingestion flotation machine for coarse solids applications. Preliminary laboratory test data and subsequent operating plant flotation kinetic performance evaluations are reviewed. INTRODUCTIONThe concentration of potash (sylvite, KCI) from halite and other salts using flotation is well understood and practice a with much success. Reagent schemes and plant circuitry for obtaining the desired product recovery and grade have been established with proven performance. These flotation circuits normally process the medium and finer size particles, less than 30 mesh (600 microns).However, often the potash market trends specifically demand a coarse product size. This emphasis, accompanied by the existing high losses of coarse (+30 mesh) potash in flotation circuits, creates the need for development of a flotation machines specifically designed for coarse potash beneficiation.This technical challenge was undertaken by the WEMCO Research and Development Group. The specific objectives of this flotation machine development program were ( l) to achieve an ""Ultra Coarse Flotation Machine"" capable of adequately suspending and transporting particles in the 4 - 30 mesh (4.75 - 0.6 mm) size range at solids concentrations of 30% or greater and (2) ascertain metallurgical performance of this machine.This paper covers the development (both theoretical and mechanical/ hydrodynamic), the field test program and results, a discussion of applicable flotation kinetics, and conclusions of this ""Coarse Potash Flotation Machine"" development project."

Jan 1, 1986

By Mel Owen, Bob Tipman

"A number of studies have identified the presence of heavy minerals in the Athabasca oil sands. A 1996 Mineral Development Agreement study into the recovery of Co-Products identified low operating costs, a simple flowsheet and access to market as key drivers in advancing interest in a viable project.Commercial bitumen extraction processes recover 50% of the titanium heavy minerals and 85% of the zircon into froth containing 1 % of the feed solids. Froth treatment tailings grade is 11.5% Ti02 and 3.6% Zr02.Processing this high grade feed in a combination of flotation, roasting, screening, gravity concentration and magnetic separation, results in concentrates of rutile, leucoxene, ilmenite, zircon and rare earths of marketable quality.A combination of high grade feed and a simple process lead to operating costs among the lowest in the industry. Low cost heavy minerals and low energy costs indicate an intriguing potential for low cost pigment production in Alberta. The production of heavy minerals from oil sands remains one of the largest untapped resources in the Province of Alberta1.0 IntroductionThis paper describes the results of an investigation into the recovery of heavy minerals from tailings produced by the major oil sands plants. The study was carried out under a Canada-Alberta Mineral Development Agreement (Alberta Chamber of Resources 1996). The MDA Co-Products Study examined the potential for the economic recovery of heavy minerals from oil sands tailings."

Jan 1, 1998

By Robert B. Parsons

"This article addresses the relationship between mine evaluation, the tax system, and economic risk. It is based on a paper presented by the author at recent seminars in Moscow and Tashkent on the subject of mine evaluation.IntroductionTaxation can have a strong influence on the feasibility of a mining project. For the most part, because metal prices are determined on a global basis, the mining concern is not able to pass on to its customers any portion of taxes which the concern has to pay. Taxes are a direct charge against the project. The purpose of the article is to highlight the various ways whereby different taxes can affect the financial viability of a mining operation.The first part of the paper identifies different forms of taxation, and the second part of the paper addresses the different forms of taxation in terms of risk analysis and impacts on the mining project. Finally, the third part of the paper makes brief mention of using the taxation system to provide incentives with respect to investment in mining activities."

Jan 1, 1993

By Robert B. Parsons

"The Department of Finance introduced draft amendments to the resource allowance regulations on July 23, 1992 that effectively nullify the decision in the Gulf Canada Limited case. Prior to the amendments it appeared that only ""directly"" related general and administrative, capital cost allowance and scientific research expenditures had to be deducted from resource profits. Now ancillary expenditures are required to be deducted. Consequently, the ability of taxpayers to claim the resource allowance is curtailed.IntroductionOn October 25, 1990 it was almost certain that taxable mines were going to get a break. The Federal Court-Trial Division had just decided in Gulf Canada Limited&apos;s favour to allow it to claim resource related tax benefits larger than what Revenue Canada evidently wished. Revenue Canada appealed first to the Federal Court of Appeal and then to the Supreme Court of Canada. On January 10, 1992 the Federal Court of Appeal agreed with the Federal Court decision and on July 2, 1992the Supreme Court declined to hear any further appeal. A mere three weeks later, on July 23, 1992, the Department of Finance issued draft ""clarifying"" measures to amend the calculation of the resource allowance. These measures effectively nullify the benefits that arose under the decisions of the Federal Court."

Jan 1, 1992

By Janet E. Halliwell

In keeping with the traditions of the Science Council of Canada - an independent and forward looking agency that applies broad and multidisciplinary analyses to the various issues it examines the author indulges in a holistic approach to the integration of the environmental, scientific, economic, and cultural concerns. This paper will characterize the changing conditions which the mining industry is facing. It will then explore the changing expectations of society with respect to environmental sustainability and how those attitudes in turn, must influence the strategic directions and attitudes of the industry, and within that, the role of science and technology.

Jan 1, 1991

By Dong-kil Lee

A ventilation improvement index (VII) was developed in an effort to propose an optimal ventilation improvement measure for a designated mine. The index was designed to incorporate both ventilation effectiveness and cost efficiency. To verify the effect of the index, a mine experiencing a ventilation problem was selected, the ventilation assessed and ventilation network analyses were conducted. In the selected mine, four areas with ventilation difficulties were detected and an improvement schemes for each area were proposed. These were simulated through network simulation and evaluated using the ventilation improvement index. As a result, an optimum ventilation improvement scheme was proposed. The improvement scheme with the highest VII value was incorporated in the design.

Aug 1, 2013

By R. H. McCorkell

Measurements of radon in air and aqueous solutions can be affected by leakage from vessels in which samples and standards are kept and by absorption and later release of radon by the materials of these vessels. The author had received various oral communications concerning the se processes : e.g ., that natural rubber and greases absorb large amounts of radon, whereas silicone rubber and grease do not; and that radon is readily lost from polyethylene bottles and that inverting glass bottles containing aqueous samples reduced radon loss from them . However, the results of actual tests and quantitative data showing these effects were not available. For this reason, it was necessary to make numerous measurements of the leakage and absorption of radon in the course of designing apparatus and methods for measuring radium and radon concentrations. It was thought that the data obtained might be of use to others, and consequently they are compiled in the present note .

Jan 1, 1980

Safety Leadership The management and leadership of a mining operation is a challenge at all times. The pressure to make production, safety, and environmental goals is intense. At some point mining cycles will put every operator into periods of time where economic issues seem to over-ride all other concerns. This is when leadership is most needed.

May 1, 2009

By Alan G. Galley

"Advances in our knowledge of the petrochemical attributes of deposit environments and of the character and extent of hydrothermal systems associated with certain deposit types has resulted in increased application of lithogeochemistry to exploration programs. Lithogeochemistry can be used to vector an exploration program toward an area of high potential through the use of a series of collapsing scales of analysis from a tectonic subprovince down to a particular stratigraphic segment. In the case of volcanogenic massive sulphide (VMS) deposits this involves the recognition ofsuitable volcanic domains, and the identification of subvolcanic intrusions and cogenetic felsic extrusive complexes. The recognition of chemical vectors within regional-scale alteration zones and associated chemical sedimentary rocks allows the geologist to identify the stratigraphic units with the most potential for hosting a base metal deposit.An integrated lithogeochemical program requires the judicious use of major, trace and rare-earth element and isotopic analysis. Standard discriminant plots may be employed to identify suitable tectonic and lithologic environments. Analysis of the chemical and mineralogical variations in broad-scale, semi-comfortable alteration zones provides a useful set of vectors to VMS mineralization. These may include contouring raw data, element ratios on XY plots, normalizing data against known rock values, or calculating mass changes in alteration zones."

Jan 1, 1995

By A. I. A. Salama, M. W. Mikhail

"The existing methods of block diagram manipulation and vanishing variable for flowsheet simplification used in coal and mineral processing circuit evaluation and optimization cannot be easily implemented on digital computer.The signal flowgraph technique is proposed to represent and simplify determination of the relationship between intermediate or end variable and the feed in the flowsheet. Typical and existing circuits are used to demonstrate the application of the proposed technique which can easily be implemented on digital computers.IntroductionRecently there has been much interest in the analysis and optimization of coal and mineral processing circuits to assist in the pre diction of coal and mineral processing plant performance. The block diagram and the vanishing variable were introduced and utilized in the analysis of plant flowsheet. Although the block diagram approach is useful, it requires manual manipulation of the circuit block diagram which may present difficulties in the situation of complex circuits. Moreover, it may not be easy to implement on a digital computer.In this paper, the signal flowgraph technique is proposed to represent the circuit flowsheet and to simplify the determination of relationships between intermediate or end variables (fractional mass) and the feed for any coal and for any mineral processing circuit comprising size and density separators. These relationships are utilized in the analysis and/or optimization of the circuit. The proposed technique is illustrated by considering typical and existing circuits."

Jan 1, 1987

By Jacques Ouellet

Outline What is Microwave energy Investigation of transparency of 40 minerals Melting of Andesite in a MW oven Numerical modeling /Computer Simulations o FEM analysis ?? Some laboratory experiments o Particle Modelling Mw Application to Rock Breakage o A MW Rock Drill Prototype Conclusions What is Microwave energy Microwave energy is an electromagnetic wave consisting two electronic & magnetic wave traveling perpendicular to each other and transporting energy with the speed of light.

May 1, 2008

By J. H. Gray

"IntroductionIn 1980, Fording Coal Limited started conceptual planning studies which led to major changes in the long-range mining plan at their Fording River Operations. These new plans have been completed and are now in operation.To assist personnel in a timely completion of this major revision to the long-range plan, existing in-house drill hole data base and scheduling systems were used and a computerized Mine Modelling and Planning System was purchased. With these tools, plan s were developed which led to completion of initial access to the peak of Eagle Mountain and the start of mining operations in March 1983. As mining area s open up and new geo logical data is obtained, detailed plan s are being extended and revised.With the geology and mine plan s on line, this work can now be done with less effort and plans ca n be adapted to provide flexibility in mining operations. Changes in market conditions can be accommodated by moving mining operations into different seams for different coal types. The computer systems are used to revise pit designs and schedules accordingly."

Jan 1, 1986

By Greg Gosson

These materials are provided for general information purposes only and do not constitute legal advice. Readers are advised to seek specific legal advice from their own counsel in relation to any decision or course of action contemplated. Outline ??What is meant by a ?current technical report? under NI 43-101? ??When is a current technical report required? ??Who makes the decision regarding whether a technical report is current? ??Examples of the types of information that make a technical report no longer current for securities filing purposes.

May 1, 2009

By R. D. Brown

"Concerns over possible additional involvement of governments in Canada&apos;s mining industry and its adverse effects on the industry &apos;s growth were a frequent topic of conversation at the recent Annual General Meeting of the CIM.Still painfully fresh in the minds of industry leaders are the disastrous results of the federal/provincial scramble over resource revenues which followed the relatively high metal prices witnessed in 1973/1974. At current metal prices, it is not surprising, then, that a nagging fear persists that these governments may once again restructure tax and other rules to the detriment of the industry and the country.This month, Tax Notes recalls some of the progress which the industry and governments have made in 1979 in the taxation of the resource sector, and urges that higher metal prices be viewed in light of the costly exploration, development and production efforts which will be required for the industry to continue to play its important role in our economy.IntroductionAt the Annual General Meeting of The Canadian Institute of Mining and Metallurgy, held in April, 1980, it was abundantly clear that there is widespread concern in Canada&apos;s mining industry that this country&apos;s tax regime may once again be blasted by ill winds of change.A stable and more favourable tax climate, as well as higher metal prices and profits, made 1979 almost a golden year for Canadian mining. However, from the tax viewpoint at least, there are some spots on the silver lining as apprehensions grow that the well-heralded battle between federal and provincial governments over oil and gas may spread to the mining sector, with serious damage to the industry and its newfound federal-provincial cooperation."

Jan 1, 1980

? A BARGE WILL BE INSTALLED IN THE BOTTOM OF A COMPLETED PIT. ? THE PROVEN BAUER CUTTER TECHNOLOGY WILL BE INSTALLED ON THE BARGE AND A DEWATERING PLANT WILL BE INSTALLED NEAR THE BASE OF THE PIT RAMP. ? THE WATER LEVEL IN THE PIT WILL BE RAISED BY 20- 40 METRES AND REMAIN CONSTANT OVER DURATION OF MINING. ? THE CUTTER WILL BE LOWERED TO MINE 10 METRE DEEP BENCHES ON A CHECKERBOARD PATTERN TO AN ULTIMATE DEPTH OF 200 METRES. ? THE 5? MINUS CUTTINGS WILL BE PUMPED TO THE DEWATERING PLANT, DEWATERED, AND TRUCKED TO SURFACE.

May 1, 2003

By K. M. Deen, E. Asselin

Hydrometallurgical processes, i.e., Cu extraction from a mineral concentrate and Zn electrowinning, are coupled in a battery-like system. A naturally-sourced CuFeS2 concentrate mixed with activated carbon is used as a positive slurry electrode separated by a membrane from the negative compartment. The Zn is deposited on the negative Al current collector from the circulating solution containing 100 g L–1 Zn2+ in 0.2 M H2SO4. In this battery-like system, both CuFeS2 oxidation and Zn deposition are possible during the charging cycle. The additional benefit of this setup is the energy storage if discharged by re-dissolving the Zn in the negative compartment. Cyclic charge/discharge testing revealed oxidation of the mineral concentrate supported by the Zn2+/Zn redox reaction. The coulombic and energy efficiencies increased monotonically to 95.6% and 43%, respectively, with approximately 7% Cu extraction during the first 10 charge/discharge cycles (completed in 2.4 hours). The discharge energy density also increased from 2.7 to 36.2 mWh L–1. In the following 90 cycles, the low energy (~14%) and coulombic (~33%) efficiencies that were obtained confirmed the progress of irreversible reactions e.g. Cu extraction from the mineral concentrate. Overall, approximately 16% Cu was extracted from the mineral concentrate over 100 charge/discharge cycles (or about 12.2 hours). INTRODUCTION Chalcopyrite (CuFeS2) is the main economic copper-bearing mineral, which is generally processed through pyro-metallurgical methods to produce Cu. However, environmental challenges with smelting, depletion of high-grade ores and a large number of impurities (some toxic) have resulted in continued research aimed at the development of hydrometallurgical technologies to process CuFeS2. There are a number of different proposed hydrometallurgical routes in the literature to treat CuFeS2 concentrates, but only a few have attained commercial acceptance (Dreisinger, 2006). Zn is another commercially important metal that is mainly produced via acid leaching of roasted sphalerite (ZnS). The pregnant leach solution is rigorously purified to remove all the soluble metal impurities, particularly those that are electrochemically more noble than Zn and present large kinetic activity towards H2 evolution (Hu & Piron, 1992; Mackinnon, Brannen, & Fenn, 1987; Mureşan, Maurin, Oniciu, & Gaga, 1996). Metal impurities such as Cu, Co, Ni, Cd, Pb, Sb, As, Ge and Fe etc., if they exist in the leach liquor beyond the tolerance limits, can decrease the current efficiency during electrowinning and deteriorate the deposit quality (Alfantazi & Dreisinger, 2001). A complete flow sheet, describing the process steps of Zn metal production from mine site to pure metal is presented elsewhere (Brown, Meisenhelder, & Yao, 1983).

Jan 1, 2019

By R. Flood

"Oil has been discovered off Newfoundland in a number of locations on the Grand Banks, the most notable and exciting being in 1979 when Hibernia was discovered. This discovery has brought new challenges to the province as well as to all of Canada. During the seven years"" since its discovery, both industry and governments have attempted to define its parameters and to find the most efficient and economical way to develop the field.A number of studies have been completed during the interval and in 1985, Mobil Canada Ltd. and partners stated that they would prefer to develop the field by using a concrete Gravity-Based Structure (GBS). IntroductionHibernia is located in an environmental climate much more severe than that of any previously developed oil field. The wind and wave conditions are similar to those of the North Sea, but unlike the North Sea, any structure on the Grand Banks would have to contend with ice floes and icebergs. Decisions had to be made on whether fixed structures could be put in place that would withstand the pressures of the ice and the impact of an iceberg, or whether structures that could be removed when such impacts were imminent would be used.Early studies in 1981, determined that it was possible to build a concrete Gravity-Based Structure which could withstand the impact of the largest icebergs that are anticipated to float in that area of the banks.Additional studies increased the knowledge of icebergs: their patterns and size, and verified the original conclusions that Concrete Gravity-Based platforms would provide a practical solution."

Jan 1, 1988

By V. Shumila, T. Butler

Microseismic monitoring systems listen to a rockmass and record ground vibrations associated with brittle rock fracture. Modern systems record continuously and can identify as many as one thousand small and possibly larger magnitude events occurring each day from induced stress change and redistribution. This paper presents examples of the real time use of microseismic information in mining applications. It shows how alerts can quickly identify large magnitude events or unexpected clusters of seismicity and how seismic re-entry protocol can help to improve safety decisions. Additionally, newly developed advanced analysis techniques applied to mine seismic data sets are shown including the use of clustering methods to see into a cloud of seismic data to identify significant activity and quantify possible planar features. The use of source parameter trend analysis is shown to be a beneficial method for interpreting changes in relative stress levels. Seismic moment magnitude distributions are analyzed using the TGR (Truncated Gutenberg Richter) and TMD (Tapered Moment Distribution) methods to estimate bvalue and expected maximum magnitude. Seismic hazard analysis is shown as a useful way to simplify a dataset and highlight seismic hot spots. The rockmass response to excavation is a complicated spatial and temporal process and microseismic monitoring is a method that can be used to help understand the location and mechanics of failure occurring in the rock ultimately helping to improve safety and productivity at a mine site.

Jan 1, 2015

By A. B. Carino

Gulf Minerals (Canada) Limited&apos;s Rabbit Lake uranium operation is located in the northern portion of Saskatchewan, 198 miles southeast of Uranium City and /34 miles northwest of Lynn Lake, Manitoba. The paper follows the ore flow through crushing, grinding, sulphuric acid leaching, countercurrent decantation, solvent extraction, ammonium diuranate precipitation, thickening, drying and tailing neutralization.

Jan 1, 1979