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By Ron Bradburn, Derek Perkins

"The Brenda mine is located in south central British Columbia, 22 km north west of Peachland, in the heart of the Okanagan Valley. Situated at an elevation of 1500 metres, the mine area straddles the divide between the headwaters of Trepanier Creek and Peachland Creek. These flow into Okanagan Lake, the chief valley water resource located 1100 metres below. The creeks are of great significance to the water management of the area as they constitute the water supply for the Municipality of Peachland, a thriving retirement community with a population of 5000. A location map is shown in Figure 1.The history of the Brenda Mine operation has been well documented previously. After twenty years of operation, the open pit mine shut down in June 1990 due to the depletion of its ore reserves. During the course of its life, it produced 109 million tonnes of waste rock which is thought to contain approximately 0.10% copper as chalcopyrite and 0.015% molybdenum as molybdenite stored in four rock piles around the pit. Similarly, approximately 200 million tonnes of tailings were produced grading 0.015% copper and 0.005% molybdenum. During operation, tailings were hydrocycloned to produce a coarse sand for dam building with the fine slime stored behind the dam. It is estimated that 40% of the tailings were used for the dam construction. The layout of the mine site is shown in Figure 2.The mine was operated under a zero discharge permit. This was achieved by diverting practically all surface water flowing towards the mine area around the site. Water affected by mine operations, was discharged to the tailings impoundment, and recycled to the mill for reuse. The recycle rate was 90% and seepage from the tailings embankment and saddle dam was pumped back to the tailings pond. Because acid drainage was not a problem with the low grade Brenda rock, runoff from the rockpiles was initially released to the local environment. However, due to the alkaline nature of the waste rock, dissolution of low concentrations of molybdenum in the site runoff waters became evident by the late 1970's. The molybdenum content of Peachland Lake, the water reservoir for the municipality of Peachland, approached the Canadian Drinking Water Standard of 0.25 ppm. By 1979, a series of diversion and collection ditches was completed to direct all runoff water from the rockpiles to the tailings impoundment area. This had a significant detrimental effect on the site water balance causing it to go into a considerable surplus condition. During normal operation, this oversupply was contained by the rate of tailings dam building. An economic shutdown of the mine during 1984 forced a limited discharge from the site to protect the integrity of the tailings dam."

Jan 1, 1995

By Z. D’Amico

"IntroductionWE HAVE HEARD quite a lot recently on newer methods -of supporting roof, such as roof bolting or the use of metal props and •booms, but, with the exception of roof bolting, these methods are confined mostly to comparatively low, regular seams and even .bolting cannot be used to hold soft sides. Thus, where a seam of coal has great variations in thickness, or where it is faulty, or where the coal sides must be supported, nothing can wholly take the place of timbering with wood. This paper will deal mainly with the method of timbering such a seam, namely, the No. 3 seam mined by Brazeau Collieries, Limited, at Nordegg, Alberta, where the full height of a thick seam is mined in development. However, a few words on one or two other systems practised in Alberta when, in development work, a thick seam is only partially mined, should be of interest.Examples of Timbering in High SeamsThere .are several methods in use today for dealing with high seams of coal. The most popular is to develop the seam by driving road-ways in the coal by some conventional method, usually recovering the full thickness of the seam on the retreat. The following examples illustrate two variations of this method.In Figure I we have a thick •seam of friable coal, with a good roof, pitching about 30 degrees, which is being mined by taking the upper part of the seam in the development work, leaving the •bench coal in place. Figure 1A shows a section through a room."

Jan 1, 1954

By C. T. Morley

The steadily increasing interest in high pressure grinding rolls (HPGR) as a legitimate alternative comminution technology for hard rock applications has led to a proportional increase in the demand for trade-off studies comparing HPGR with more established approaches, typically SAG-based but including AG and stage-crushing designs. The primary trade-off is between a) the higher capital cost typically incurred with HPGR-based designs and b) the higher operating costs of the more traditional technologies. However, if, through circuit design innovation, the capital cost penalty of HPGR circuits could be eliminated or reversed, then the need for trade-off studies would diminish.

Jan 1, 2012

By D. J. Parker, G. B. Tupper, I. Govender

Positron-Emission-Particle-Tracking (PEPT) has enabled the non-invasive observation of charge and slurry transport in model mills under operational conditions. We use high quality PEPT data to infer that the charge motion can be effectively described by a non-Newtonian granular fluid. An improved theory for slurry transport, including inertial effects, is presented.

Jan 1, 2012

By Rodney S. Read

Both crystalline and sedimentary rocks are being considered to host a deep geological repository (DGR) for nuclear fuel waste in Canada. In the past several decades, considerable research has been conducted around the world to better understand geomechanical processes associated with development and long-term performance of a DGR. The Nuclear Waste Management Organization?s (NWMO?s) technical research and development program is examining a number of potentially suitable rock formations to support implementation of Adaptive Phased Management, Canada?s approach for long-term management of nuclear fuel waste. Rock engineering will play an important role in siting, design, and construction of a DGR for nuclear fuel waste. Post-construction activities such as excavation maintenance, monitoring, decommissioning, and closure will also involve rock engineering. The type of host rock selected for a DGR will influence the scope of rock engineering activities and related research requirements. This paper outlines key rock engineering aspects to be considered in developing a DGR in sedimentary rock.

May 1, 2009

By Paul MacLean

MAC TSM ?Mining and Biodiversity Conservation 1.Corporate biodiversity conservation policy, accountability and communications 2.Facility-Level biodiversity conservation planning and implementation 3.Biodiversity conservation reporting ?Activities indicative of level AA -AAA (formerly 4-5) performance: ?Independent verification ?Integration into broader business strategy and planning processes ?Engagement with communities of interest ?Commitment to actively partner with other organisations for biodiversity conservation

May 1, 2011

By E. V. Manlapig, U. Erol, V. Ross, K. Tshimanga

Lonmin RoM ball mills are treating two types of feed ore produced by conventional mining and mechanised mining methods. It was reported that reduction in mill throughput was observed when treating the mechanised mining ore. Detailed grinding surveys were conducted for troubleshooting. Ore samples were collected for breakage characterisation using a JKRBT based on different particle density components. XRD analysis was conducted to investigate the association of minerals with density components. The plant surveys and the breakage characterisation tests all suggested that the two mining methods did not significantly affect either the ore breakage properties or the RoM mill performance. Instead, the mill discharge open area exerted a remarkable influence on mill throughput. The RoM ball mill operated at Lonmin K4 Concentrator has been proven to be a versatile mill that performed stably with variations in feed size distribution and feed ore changes by different mining techniques. The reasons are elucidated by the multi-component breakage characterisation and the plant surveys data.

Jan 1, 2012

By A. Fakhimi

The effect of porosity on mechanical behavior of rock has been studied in the past using both experimental and numerical techniques. One important aspect of this study that has not received much attention is the role of void size and distribution on the mechanical behavior of rock. In this study, the CA2 computer program that is a hybrid discrete-finite element program for two-dimensional simulation of geomaterials is used. Numerical specimens with different macro-void sizes are loaded uniaxially. The Young?s modulus, Poisson?s ratio, uniaxial strength and crack initiation stress are studied. The numerical results are compared with the database of experimental tests on Plaster of Paris specimens containing Styrofoam spheres with different void sizes and porosities. It is shown that the macro void spatial distribution is partly responsible for the scatter of the experimental data. It is also shown that not-only the porosity but also the pore size can affect the deformability, crack initiation stress and rock strength.

May 1, 2009

By W. Dan Hausel

"Abstract-Hundreds of diamonds have been found in the United States. The majority of the discoveries occurred during the 19th century as a by-product of placer gold mining. Most of these early diamond finds have no known source, and in many cases are situated in areas unfavorable for diamond exploration based on current models that require kimberlite or lamproite to be emplaced in a stable Archean craton or Proterozoic craton margin.Diamonds have also been recovered in situ from lamproite at Murfreesburo, Arkansas, from kimberlite in the Lake Ellen region of Michigan, and in several kimberlites in the Colorado-Wyoming State Line district. Unverified reports also suggest that diamonds may have been recovered from other related intrusions at a number of localities in the United States."

Jan 1, 1995

By Ayako Iwakoshi

Highly concentrated pastes of gold nanoparticles were successfully produced by use of a special kind of protective polymer and a mild reductant. Solid part of the pastes consists of up to 85wt% of gold nanoparticles, 10~30 nm in diameter, and residual protective polymer. This component can be diluted by any kinds of solvent at arbitrary rates. Electronics, optics, catalysts, colorants and surface metal coatings are possible application fields. 1. Introduction Noble metal nanoparticles are of interest in a variety of fields ? such as colorants, metal coatings, electronics(1), optics(2), and chemical catalysis(3). Especially, in the color field, the gold nanoparticle has been known as an aesthetic red colorant for stained glass and fine glassware, such as Venetian glass. The mechanism of coloring is attributed to surface plasmon absorption of gold nanoparticles(4,5). The gold nanoparticle in stained glass shows very clear red color, which is very durable for hundreds years. On the other hand, the red color of organic pigment in paint films often fades away within several years. We intended to reproduce the elegant and stable coloring of stained glass in paint films. In order to color a very thin, 20~50?m, paint film like stained glass, production of highly concentrated dispersion of gold nanoparticle is necessary. To achieve this, there were two issues to be overcome. One is how to prevent the coagulation of gold nanoparticles in highly concentrated solution. So far, several methods to prepare gold nanoparticles(6,7) were reported. But only a few methods succeeded to stabilize the gold nanoparticle dispersion at higher concentration than ppm order. The other is controlling of the particle size, this is because the color of gold nanoparticles is very sensitive to the particle size. Only when the particle size lies around 10 nm, the suspension exhibits red color like stained glass.

Oct 1, 2003

"The Dome Mine, located in South Porcupine Ont. has been in operation since 1910 and is owned and operated by Placer Dome Inc. The current milling facilities were constructed in two phases with the first being commissioned in 1982. It consists of a grinding, gravity separation, thickening, and leaching circuits. The second phase was commissioned in 1988 with the addition of the CIP, stripping, electrowinning, and carbon regeneration circuits.It is now common practice in the gold processing community to add liquid oxygen to leach circuits to increase both recovery and kinetics. Along with these benefits the metallurgical group at the Dome realized the potential to replace compressed air with liquid oxygen as a source of oxygen for the dissolution of gold. A plant trial of liquid oxygen was undertaken during the fall of 1991. The results of this first test were favourable enough to warrant further investigation, and a second plant trial was conducted in December 1991.The data generated as a result of each trial revealed that oxygen could be economically substituted for compressed air as a source of dissolved 02. The energy savings in required horsepower enabled a rapid payback period. Thus the project was approved in the spring of 1992 and l should be operational during the final quarter of 1992. INTRODUCTIONIn a continuing effort to reduce operating costs and improve recovery at the Dome mill it was decided to investigate the feasibility of adding liquid oxygen (02) to the leach circuit. It is now common practice in the gold processing community to add 02 to the leaching process to increase both kinetics and recovery. It was anticipated that an increase in kinetics would allow us to eliminate one or more leach tanks while maintaining acceptable recoveries. The metallurgical group felt that along with these benefits, the potential was also there to reduce power consumption through the reduction in the processing of compressed air which is quite costly (12 cents/1000 cubic feet per minute in 1991)."

Jan 1, 1993

By Sarah Bélair, Denis Beltrami, Deka Moussa Ragueh, Valérie Weigel

"Scandium is a highly valuable element belonging to the rare earth elements (REE) but it has different chemical and physical properties from those of lanthanides. This metal is generally used in aluminum-scandium alloys and in fuel cells but the development of its market is slowed down by its high price (more than 1000 US$/kg for a 99.0% grade product). Indeed, the low scandium content in the continental crust (an average of 22 ppm) and the difficulties to extract it selectively from solutions containing high impurity concentrations increase the cost of the recovery processes. Nowadays, scandium is primarily recovered as a byproduct.ERAMET is developing a hydrometallurgical process in Gabon (Mabounié) in which the scandium content in the deposit reaches 10 to 100 ppm. The Maboumine project consists in the extraction and purification of uranium, niobium, tantalum and REE from Mabounié ore. In the frame of this hydrometallurgical project, ERAMET had also studied the feasibility to recover scandium as a byproduct. During the ore leaching, uranium and rare earth elements including scandium are solubilized into the pregnant leach solution (PLS). Among the various methods investigated to recover scandium from the PLS, liquid-liquid extraction using Primene JM-T as extractant was chosen and tested first at laboratory scale and then at pilot scale. Selective stripping of the loaded organic was carried out by using phosphoric acid solution, allowing the selective recovery of scandium from thorium and zirconium partially extracted from the PLS by Primene JM-T under the process conditions."

Jan 1, 2016

By B. W. Raymond, D. W. Zandee

"IntroductionCoal deposits are found in many regions in Canada and vary widely in their age, quality and rank. All classifications of coal except anthracite are found in significant quantities in this country.Deposits in the Maritimes are mainly bituminous; Lignite is found in Saskatchewan and Ontario and sub-bituminous coal in the plains region of Alberta. The Rocky Mountain coalfields of Alberta and British Columbia contain low and high-volatile bituminous coal and, in a few places, semi-anthracite. The British Columbia interior contains deposits of semi-anthracite, bituminous, sub-bituminous coals and lignite. The Yukon and Northwest Territories also contain substantial deposits of bituminous coal and lignite.Currently Nova Scotia produces both thermal and metallurgical coal, Saskatchewan produces lignite and Alberta produces both sub-bituminous and bituminous coal for thermal purposes. Large deposits of metallurgical coal are now being exploited in the Rockies arefl of British Columbia and Alberta by open pit methods. The raw coal is treated in large capacity preparation plants to remove refuse and upgrade the product to a consistent metallurgical quality with respect to ash, moisture, volatile matter and coking properties.The treatment of coal involves crushing, screening and cleaning by dense medium, jigs, water-only cyclones, tables and froth flotation to produce a diverse range of coal products differing in quality and size for various end uses.The chapter on Crushing and Screening Circuits was concerned mainly with crushing of metalliferous ores to produce a concentrate of one or more valuable minerals which normally constitute a small portion of the original mass of the material treated.Coal differs physically from ores in many ways such as lower specific gravity, relatively large volumes but low tonnage of product, and its habit of absorbing moisture requires extensive dewatering processes more complicated than settlement and filtration. Most significant, for this paper at least, is the fact that crushing coal is not as energy intensive and much smaller equipment is applicable.Crushing and screening of ores is intended to reduce the size of all constituents as quickly and efficiently as possible to allow liberation of the mineral particles. The crushing of coal is different in that the coal is not the minor constituent and the production of fines, in the initial stages at least, is highly undesirable. The basic objectives of crushing coal are the reduction of run-of-mine material to sizes suitable for cleaning or further reduction of coal to market sizes."

Jan 1, 1989

By R. Maxwell

"At Opemiska Copper Mines we have, over the past four years, operated 300 cu. ft. and 700 cu. ft. flotation cells as roughers, scavengers and cleaners and found them competitive with conventional flotation cells on a cu. ft. basis on all phases of flotation.The economics are very much in favour of the large cells for the following reasons:Power consumption is 35 to 40%, of conventional machinesMaintenance cost is about 20 to 25% of conventional machinesSpace required is about 30 to 35% of conventional machinesInstallect cost is about 40%, of conventional machinesTo put the above in more concrete terms below is what we are doing at Opemiska:1. Increasing mill capacity from 2000 to 3000 T.P.D. and will use only 5Cff, of the flotation space for 3000 tons that we used for 2000 T.P.D. with conventional flotation machines.2. Will require only 10 flotation cells for 3000 tons against 85 conventional cells for 2000 tons.3. Cells will be, one 2000 cu. ft. rougher, six 700 cu. ft. scavengers (2 banks of 3 each) and one cleaning circuit using three 300 cu. ft. cells.You will note that in this 3000 ton per day plant, we are going to have only ten cells. Had we put in conventional cells for this tonnage, we would have needed 120 cells."

Jan 1, 1970

By Wayne F. Luinstra, Frédérique Vincent, André R. Laplante

"A test to determine the amount of gravity recoverable gold (GRG) in an ore is described. Typical GRG results are given; possible uses are discussed. A case study of how the technology was used at Hemlo Gold Mines is presented.IntroductionUsing gravity to supplement either flotation or cyanidation is a well established practice in the gold industry. It differs from most recovery circuits in that most of the gold recovered by gravity would be recovered in any case by the circuit downstream, be it flotation or cyanidation. The economic justification of gravity is therefore based on small margins (for example. a net smelter return of gravity gold of 99%, as opposed to 94% by flotation). It was easily demonstrated when either flotation or cyanidation were relatively inefficient processes, and labour costs low (as gravity can be labour intensive). Over the past thirty years, the advent of better flotation machines (flash, column, high capacity), more effective collectors, and better control systems has increased flotation's metallurgical performance, thereby decreasing the incentive for gravity recovery. Cyanidation technology has undergone similar changes, with the advent of activated carbon, oxygen and lead nitrate addition, and improved impeller design.Today, gravity could remain an attractive option only inasmuch as it can be implemented with very low capital and operating costs. This has resulted in a relative shift away from gold gravity recovery (except for alluvial deposits), in the seventies and eighties. For example, as of the early nineties, gold gravity recovery has disappeared from the typical South African flow sheet. The advent of the Knelson Concentrator, at the beginning of the eighties, foreshadowed a resurgence of gravity recovery, as gold's grinding and classification behaviour (Banisi, Laplante and Marois, 1991) makes it possible to achieve adequate gold recoveries with very simple, Knelson based, gravity circuits (Laplante et al., 1994).Consider for example the Hemlo recovery circuit, made of a single 61 cm x 122 cm (2' x 4') screen, an automated 76 cm (30"") Knelson feeding a Gemeni table, to produce a 70-80% Au concentrate which accounts for approximately one fourth of the gold production (about 3 million grams per year). The low capital and operating costs make it possible to justify the gravity circuit on the basis of savings in other operating costs (e.g. fewer carbon stripping and reactivation cycles). Any improvements in recovery, which would at Hemlo be difficult to measure, would be additional benefits. Such a circuit is rapidly becoming a standard in Canadian and Australian operations.The justification for installing a gravity circuit must be first based on an estimate of how much gold it will recover (irrespective of what the potential benefits are). This is a function of the nature of the gravity circuit to be installed; however, Knelson circuits, by their very simplicity and efficiency, limit the options. This leaves the amenability of the ore to gravity recovery as the single most important parameter. Various approaches can be used to characterize this response (Woodcock, 1993). The present work sought a route which would fulfil the following criteria:"

Jan 1, 1996

By T. McCallum, B. Wellbrook, T. Ratnaweera

Leaching of copper (Cu) concentrates produces elevated concentrations of Cu and acid, which makes solvent extraction (SX) processing more challenging. Maintaining extraction targets can be more difficult with higher pregnant leach solution (PLS) grades, and variability of PLS Cu and acid can lead to increased chemical iron transfer. Diluting concentrate leach feeds with an existing heap leach inventory makes SX processing easier. However, considerations about how much to dilute and where to distribute the flow into the SX configuration must be carefully evaluated, given their impact on metallurgical performance. In this paper, characteristics of a concentrate leach feed are discussed, along with considerations for processing by SX. Also reviewed are pilot plant results of concentrate leach distribution into SX and plans for commercial testing. INTRODUCTION Hydrometallurgical processing of copper concentrates continues to gain interest from the industry. Treatment by smelting and electrorefining continues to dominate, accounting for ~80% of global copper production, but is faced with its own challenges (Li et al, 2017). The case for increased hydrometallurgical processing has been discussed as high grade ore deposits are diminishing, capital costs for smelting are high, and the environmental aspects present challenges for sustainable practice. The hydromet copper industry is also turning a corner as easily leachable copper oxide deposits are depleting, and excess SX-EW capacity exists in certain regions. The transition to hydrometallurgical processing of copper concentrates will take a bit of effort as leaching of copper sulfides is difficult and byproduct credits must be considered. Various POX leaching processes have been studied and proposed to the industry as viable practices. Of the many processes, commercial use has been practiced with the Mount Gordon Copper Process, total and partial pressure oxidation by Freeport-McMoRan at their Bagdad and Morenci, Arizona complexes, the Sepon Copper Process in Laos, and the bioleach BIOCOP™ process in Chile (Dreisinger, 2016).

Jan 1, 2019

By Z. D. Hora

Sedimentary phosphate-bearing rocks are found over a considerable area of so utheastern British Columbia that extends from Fernie east to the Alberta-British Columbia boundary and from the International Boundary northward to the headwatei: s of the Elk River. Phosphatic beds occur at the following four stratigraphic levels: 1. lower part of the Banff-Exshaw sequence of Mississippian age; 2. lshbel Formation of Permian age; 3. base of the Fernie Group of Jurassic age; 4. belemnite bed within the Rock Creek Member of the lower part of the Fernie Group. To date, considerable tonnages of phosphate rock have been proven in the area. However, no commercial production has been initiated because of a relatively low P2O5 grade. Data on assays and thicknesses of the phosphatic beds are in part recalculated from the paper by Telfer (I 933) and in part from assessment reports filed at the British Columbia Ministry of Energy, Mines and Petroleum Resources.

Jan 1, 1984

By Craig Ford

Inmet Mining is committed to implementing the highest corporate responsibility standards in its mining operations worldwide. Inmet is 100% owner of Minera Panama, a world-class copper project that is currently in the feasibility phase in north-central Panama. Panama has limited experience with modern mining, limited mining capacity, and the project context involves significant social, environmental and political complexity. The Project area is remote with recent in-migration of latino and indigenous people, informal and small-scale mining, local subsistence populations and considerable biodiversity value, coupled with a complex jurisdictional setting. In short, it is increasingly the kind of project mining companies are taking on because the easy projects have already been developed. With such challenging conditions, anticipating and managing social risks is critical to effective project management. To this end, between August 2007 and the third quarter of 2009 Inmet seconded Monkey Forest Consulting Ltd to the project to assist Minera Panama in building and implementing an effective, early phase external relations strategy. The team was also tasked to find and develop a locally based team that could sustain success through project development and into operations. Today?s presentation was created by Inmet and Monkey Forest and describes some of the lessons learned in implementing an effective early phase process for managing social issues.

May 1, 2010

By J. Kicki

The paper depicts the current status of the EKSPERT mining machinery management system and shows the prospects for its further development. The system is the result of a rare attempt to utilize the comprehensive dataset; this refers to a precisely identified group of users and is used to develop a solution with a scope that encompasses other areas of activity within the company. The authors present the incredible flexibility and usefulness of the system used at KGHM Polska Miedz S.A. for everyday control of the mining machinery fleet. The issue of visual aspects of the reports generated by the system is handled separately and used as a tool allowing for implementation of the methodological assumptions of EKSPERT. A concept for creating a system for assisting decision making in the process of mine management with the use of IT tools and production monitoring is also discussed. The solution is based on integration of information from both the monitoring field and visualization of the technological process around the Production Reporting Center.

Aug 1, 2013

By A. Probst, J. A. Finch

"Solids concentration (% solids) profiles and the clear liquid/slurry interface level (mudline) were determined from conductivity measurements in thickeners at Falconbridge' s Strathcona mill (Ni concentrate and non-mag thickeners) and Kidd Creek Division (Cu, Zn concentrates and final tails in the concentrator and thickeners in the Zn plant).The conductivity measurement system consisted of a probe 1.5 m in length with 24 electrode cells, a 24-channel relay, a conductivity meter and a computer. A conductivity profile is collected which locates the mud-line by the sharp change in conductivity. The conductivity measurements are readily converted to solids concentration profiles without need for calibration.The results from the conductivity measurements were compared with those from pressure profiles and direct measurements on local samples obtained using a modified Noranda sampler.It is concluded that the conductivity technique is applicable to locate the mud-line and to estimate the solids concentration profiles in thickeners. This on-line information could improve the operational efficiency of industrial thickeners.INTRODUCTIONAn automated, on-line technique for detecting the clear liquid/slurry interface (or mudline) and the variation in solids concentration with depth would enhance thickener operation and control. In some processes such enhanced control offers significant benefits. For example, in hydrometallurgical operations solid/liquid separation is often the process limiting step. Water treatment plants are increasingly expected to operate remotely and reliable sensing is vital.Current attempts to detect the mud-line include reflection of some signal (e.g. sonar), floats (Dahlstrom, 1985) and measurement of pressure (Rosenblum, 1991), and in one case, natural radioactivity of the solids (Johnston and Simic, 1991). A recent commercial development uses reflection from a vertical array of optical transmitters/sensors, which also gives local solids concentration (BTG Inc., 1991)."

Jan 1, 1993