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By Mike D. Riley, Alan V. Bell, Ernest K. Yanful

Acid mine drainage (AMD) research under the MEND program has been ongoing since 1988 at the Heath Steele Mines waste rock piles including sulphide material, outside Newcastle, NB. In 1989 approximately 10,000 mt of waste rock was placed on a prepared sand base with an underlying impermeable membrane. The waste rock pile was heavily instrumented for measuring oxygen concentrations and temperatures. In September 1991, a composite soil cover designed for the Heath Steele climatic conditions, using local soils, was placed over the pile, creating a totally enclosed system. Moisture content and oxygen probes were installed within the composite soil cover to monitor changes within the soils over time, while two large-size lysimeters were installed below the cover to monitor the hydraulic conductivity of the cover. The waste rock site has been monitored on a monthly basis since installation of the cover, for performance of both cover and waste rock. The monitoring shows very clearly that the placement of the composite soil cover has had a major impact on the generation of AMD. Major reductions in temperature and oxygen concentrations within the waste rock pile indicate that the cover has significantly inhibited the oxidation reaction that generates the AMD. Performance data have shown that the cover has maintained its integrity under the climatic conditions of the area.

Jan 1, 1995

By A. R. Laplante

"In this paper, the performance of the Knelson Concentrator and of the batch and continuous Falcon Concentrators are compared. The units are based on different operating principles, and as such they perform quite differently. The Knelson yields very high free gold recoveries over a wide size range of both the recovered and rejected species. It is ineffective in recovering very fine ( <15 µm) or flaky gold, as encountered in flotation feeds, concentrates or tails. It is the: preferred unit for gold recovery from grinding circuits. The batch Falcon is effective in the fine range, typically less than 37 µm for gold. Its recovery zone is quickly saturated when there is significant heavies in the feed. It works best as a pre-concentration unit. The continuous Falcon is a versatile unit which is capable of recovering fine heavies (density down to 5 g/cm3 ), especially from coarser gangue. INTRODUCTIONThe purpose of this presentation is to describe the mode of operation of two Canadian centrifugal concentrators, the Knelson and Falcon. It is hoped that it will prove informative to prospective users in the selection, testing and optimization for applications of either machine. The work is based on testwork both in Canadian mills and at McGill. I am indebted to many colleagues at these locations. Appropriate references will be made to articles further describing the work, either already in the open literature or in preparation.Although this work is meant to be more practical than scholarly, it is appropriate to begin by considering how the two units achieve selective recovery. This will become useful in establishing a suitable testing methodology, which will then be described, and interpreting typical results. In the last section I will attempt to define appropriate applications for the two units. This is a thankless task, as I am likely to miss some applications or to make projections based on partial results, as much of the work is still in progress. In deference to the reader and both manufacturers, areas where reasonable doubt still remains will be identified."

Jan 1, 1993

By John S. Stevenson

The Twin ''J' mine is on mount Sicker; 8 miles by road northwest from Duncan; on Vancouver island. It includes the old Lenora; Tyee; and Richard III mines; formerly under separate ownership but now under the single ownership of Twin "J' Mines; Limited.

Jan 1, 1954

By Nirmal Weerasekara, Jochen Franke, Malcolm Powell, John Favier

Mill liners serve the dual purpose of protecting the shell from wear and transferring the rotary motion of the mill to an effective grinding action. As the liners wear, the efficiency of energy transfer changes, so there is balance between liner profile for wear and for milling efficiency. A tool that can simultaneously predict the evolution of the liner profile and the associated change in milling efficiency should prove most useful in optimal liner design. This paper presents such an approach, based on measured 3D liner profile data informing 3D DEM simulations of charge motion and liner wear modelling.

Jan 1, 2012

By F. Q. Barnes

"Uranium, thorium and yttrium have been recovered, since the 1950s, from pyritic quartz-pebble conglomerates occurring in the basal sediments of the Quirke syncline at Elliot Lake. Gold, an element of interest in similar type deposits occurring worldwide, is a very minor constituent of the Elliot Lake conglomerates because the provenance area of the sediments had few gold-bearing rocks.Uranium, thorium and rare elements are found in resistate and diagenetic minerals occurring in the matrix of the conglomerates. The valuable elements are recovered from the acid soluble minerals during the milling process.Large uranium reserves occur in mines found on both limbs of the Quirke syncline. Major reserves are being developed on the South Limb of the syncline, where the Stanleigh Mine, among four past-producers, has been reactivated.IntroductionUranium and thorium commonly occur in anomalous amounts in coarse basal sediments. Radioactivity in basal conglomeratic sediments is generally attributable to resistate minerals, that rarely occur in concentrations high enough to be of economic significance. One type of basal conglomerate found worldwide, in Precambrian cratonic basins, has uranium or uranium and gold concentrations large enough to be of economic interest. Principal among the occurrences are the pyritic quartz-pebble conglomerates of the Huronian in Canada, of the Witwatersrand in South Africa and at Jacobina in Brazil.The uranium and gold mineralization of these conglomerates was derived from provenance areas where both elements occurred and were later concentrated through source degradation and deposition in placers in a reducing environment. Only the Huronian conglomerates, generally much richer in uranium but with negligible gold, have been exploited solely for their uranium content.The uraniferous conglomerates of the Huronian at Elliot Lake, 500 km north of Toronto, continue to represent a major world source and supply of uranium concentrate."

Jan 1, 1986

By G. Vibert Douglas

It has long been recognized that there are considerable difficulties connected with the physical and chemical explanation of shoots of ore. The literature of Mining Geology has frequent references to this subject; but the reasons given for the actual location of primary ore-shoots have been very tentative. In practice, the geologist or miner depends to a great extent on sampling and assaying to determine the boundaries of profitable ore within the mineralized zone. An ore-shoot is a portion of a mineralized zone which has a sufficient concentration of valuable minerals to make it ore. Ore deposits have been classified according to many schemes. There are classifications based on morphology and on genesis. However, it is also possible to classify hypo-gene hydrothermal ore-bodies in terms of ore-shoots or vice versa. A.-Ore-deposits in which the whole of the mineralized zone is ore, which is the same as saying that the ore-shoot extends throughout the mineralized zone. An example of this type of deposit would be the pyritic mineralization of Rio Tinto. B.-The second type would comprise those deposits in which the ore-shoots bear some relation to the geological structure of the area: all deposits in which &apos;bonanzas&apos; occur in folds in the zone, at the intersection of veins along certain fault (or joint) features and other such controls. There are a great many examples of this type: (a) The Rhodesian copper lodes, where Bancroft and Gray have pointed out the association of the shoots of ore with drag folds. (b) A similar association has been pointed out by Faribault for some of the gold veins of Nova Scotia, e.g., Mount Uniacke. (c) The great bonanza of the Comstock lode in Nevada. C.-Deposits in which the localization of ore has been effected by the chemical character of the wall-rock. Examples of this type are the Fahlbands of Scandinavia, and the &apos;indicator&apos; deposits of Ballarat, Australia. D.-Lastly, deposits in which there is apparently no structural and no chemical control.

Jan 1, 1934

By B. R. Casement

"Managing safety on the basis of after-the-fact reaction to accidents, can never be more than partially successful. Injuries will occur as long as the underlying potential for them still exists. Unless unsafe actions and conditions are systematically decreased, no program can have more than a short-term success.The pro-active Bullmoose loss control process, instead, focusses on heightening awareness of work habits, to prevent incidents by reducing their potential.Any safety program will be doomed to failure if the development of safe work habits depends on the safety supervisor or a safety committee. At Bullmoose the focus is on the critical actions out of which losses emerge. The successful application of performance-related feedback is achieved by taking safety, health, and environmental concerns into consideration on every level, and, by doing the right thing in every job done.What is an Exceptional Loss Control Program?If an accident in an organization creates a flurry of interest, resulting in ""cracking down"" on violations for a short period of time then an ""exceptional"" loss control program exists. Unfortunately, exceptional here does not refer to the effectiveness of quality of the program but to the fact that the organization is managing loss control by exception. The degree of management attention in an ""exceptional"" safety program varies over a period of time, remaining low as long as the rate of losses stays within management&apos;s acceptable control limit (Fig. I). When the losses rise above this, management becomes motivated to begin ""exceptional"" efforts to manage losses. When the rate falls again to within the accepted limit, efforts to control losses take a back seat.Such a strategy guarantees that losses will be tolerated or ignored as long as the actual rate is below the acceptable limit. Simply to lower the limit would not reduce losses, but would result in an increased number of flurries of management attention to loss control. This ""on-again, off-again"" style of management teaches supervisors and others that basic loss control is not as important as are statistics."

Jan 1, 1993

By J. A. Eisele, D. L. Pool

"The Bureau of Mines has developed a particle agglomeration technique to improve the flow of leaching solution through heaps of low-grade gold-silver ores which contain clays. Benchscale experiments and industrial practice have shown that the percolation rate of cyanide leaching solution is greatly enhanced by mixing the ore with Portland cement as a binder, moistening the mixture, mechanically tumbling to form agglomerates, and aging before heap building and leaching. A slight modification ofthe technique allows its application to precious-metal-bearing tailings, which cannot normally be treated by heap leaching because they are too fine. IntroductionMany low-grade gold and silver deposits and tailing materials from former mining operations in the western United States are potential sources for precious metals. These sources are too low grade or too small to support the capital cost of a conventional cyanidation plant but have stimulated the development of lowcost procedures, such as extraction of the precious metals by heap leaching with cyanide. The Bureau of Mines has investigated methods to improve the recovery ofgold and silver by heap leaching these low-grade materials.For heap leaching to be successful, the crushed and stacked ore must have good permeability so that uniform distribution of the cyanide leaching solution through the heaps can be achieved. Some of the most difficult gold and silver ores to treat by heap leaching are those containing excessive amounts of clays, or fines generated during crushing. Excessive amounts of slimes, generally minus 50-micrometre or 270-mesh Tyler sieve size particles, in the heap feed will slow the percolation of the leaching solution, cause channelling, or produce dormant or unleached areas within the heap, resulting in long leaching periods and low extractions. In extreme cases, the clays or slimes can seal the heap and cause the leaching solution to run off the sides of the heap rather than through it."

Jan 1, 1987

By Z. D. Hora

Sev_eral dozen si lica occurrences have been reported from various parts of Brit ish Columbia. Some represent hydrothermal veins or parts of pegmatite bodies; other are recrystall ized sandstones. Several vein type deposits were mined for smelter flux and as a source of white chips for stucco dash and simi lar products. Some quartzites were studied as potential sources of high-grade silica for ferrosilicon and silicon metal production. The province's only production of silica for ferrosilicon has come from a pegmatitic quartz plug near Oliver in southern British Columbia. Its reserves are now practically depleted.

Jan 1, 1984

By J. D. Botsford

Westmin Resources Limited's H-W orebody on Vancouver Island is a copper/lead/zinc massive sulphide deposit that has been in production since 1985. The sulphur content of the ore averages 28% and in some stopes is as high as 53%. Several minor secondary sulphide dust explosions have occurred in development headings and cut and fill stopes, but as yet no known explosions have occurred in blasthole stopes. This pa:per reviews the history of sulphide dust explosions in the H-W Mine, factors contributing to the explosions and the preventative measures taken to control them.

May 11, 1988

By W. V. McKnight

The paper discusses the equipment and methods used to establish some of the characteristics of a braking system. Some typical tests are described and an explanation of the approach used to derive information from the recorder charts is given.

Jan 1, 1966

The following briefing is intended to provide an overview of the present and future challenges associated with our access to a secure and adequate supply of electrical energy necessary to support safe, productive and sustainable mining initiatives at Musselwhite. Contents ??Site power demand vs. current available supply ??Supply technical deficiencies ?adequacy and security of present supply ??Present internal generation ??Anticipated future internal generation requirements ??Increased requirements necessary for planned expansion ?demand/security ??Goldcorp?s strategy to achieve required supply ?transmission line initiative ??Subsequent benefits to others from the Goldcorp initiative. ??Economic impact of MusselwhiteMine on the northwest region ??Anticipated economic impact of planned expansion ??Expected life cycle of MusselwhiteMine ??Comparative energy costs for similar operations in other jurisdictions ??Conclusions ??Anticipated action plan ??Energy Management Initiatives ??Site Orientation

May 1, 2009

By G. E. Agar, W. B. Kipkie

"This paper deals with the prediction of locked cycle flotation results from data developed from individual batch tests. A postulate is made that the distribution of material in a separation stage is determined by the chemical conditions and the flotation time and that this distribution can be characterized by split factors which are constants for a fixed set of conditions. With this premise, it is demonstrated that a steady state balance can be calculated for a circuit.Although the necessary equations can be solved algebraically, a computer program was written that uses an iterative tec1nique to arrive at the steady state balance. The program is written so that a variety of circuits can readily be simulated.A number of examples are examined to demonstrate the validity of this simulation procedure. The sensitivity of the material balance to changes in the split factors was examined. Data developed from different flowsheets is presented on sulfide ores, on copper-nickel separation and on silver flotation,"

Jan 1, 1978

By Michel Ruel, Ali Soltanzadeh

This paper describes how to make advanced control choices when difficult processes need improvement. The decision-making process involves choosing between a rules-based approach and a model-based approach as well as weighing benefits and drawbacks, complexity and simplicity, investment and results. This paper will present briefly each solution: basic control, advanced regulatory control, model predictive control and expert systems such as fuzzy logic controllers and neural networks. Three examples are presented: ARC (Advanced Regulatory Control) on pH in a comminution circuit, MPC (Model Predictive Control) for combustible management and FLC (Fuzzy Logic Control) on a Semi Autogenous Mill. The article then proposes a decision tree for selecting the most appropriate approach. A table will compare usage, development, commissioning, maintenance and lifecycle costs for each approach. Finally, conclusions and suggestions will summarize the methodology.

Jan 1, 2014

By Zainelabdin Khalid Zainelabdin Elfaki

The influence of partially replacing cement with marble waste on the workability and compressive strength of concrete bricks was investigated. Three replacement percentages, 10%, 20% and 30% weight marble waste, were used with different curing times of 7, 14 and 28 days. Two specimens were prepared for each percentage and curing time. For this study, marble powder from the Mining House Company in Saudi Arabia was used. It was observed that the replacement of cement in Concrete brick with marble waste enhanced the loading strength and the workability of the prepared concrete bricks. It was also observed that 20% replacement of cement with marble waste was the best replacement percentage compared to the other replacement percentages tested. Marble waste from manufacturing companies, either in powder, sludge or slab form, has negative impacts on the environment. In contrast, reusing marble waste has both economic benefits (i.e., selling the marble waste) and lessening the need for raw resources.

Jan 1, 2014

By Robert B. Parsons

"It is generally acknowledged that Canadian and foreign-based mining companies are spending relatively fewer dollars in Canada and more dollars abroad than was the case not many years ago. It is common to see the Canadian tax system being fingered as one of the causes in this shift in direction. However, if one takes the time to peel away the surface of our tax system, and to probe a little deeper into its substance, it will be found that the Canadian taxation of mining is generally quite competitive. IntroductionCross-border shopping in the mining industry? - Absolutely! Economics 100 teaches that dollars are votes in the capitalist system, and mining companies are going to cast their limited number of votes where they can achieve the highest return at the least risk. The Canadian consumer knows that taxes are a major factor in cross-border shopping, and mining company executives know that the same tenet holds true in their industry. Unfortunately, mining operations are subject to such a bewildering array of tax rules that making an intelligent decision is not always an easy matter.Statutory Tax RatesConsider, for example, the ""statutory"" tax rates shown in Table 1. (Statutory tax rate in this table refers to the simple sum of federal and provincial tax rates on profits as specified in the tax legislation.) Looking only at the total statutory tax rates (such as 66070 for Manitoba) , one might quickly observe that the Canadian mining industry is subject to a truly onerous tax regime, especially as compared to the United States where statutory tax rates can be in the 34% range."

Jan 1, 1992

By F. Rosenblum, P. Spira

A laboratory test has been developed for assessing the patential hazard from self-heating of sulphides. The technique consists in measuring the rate of self-heating, from near ambient temperature, of a 1-kg sample in an insulated chamber controlled at standard atmospheric conditions. The rate of oxygen consumption is monitored simultaneously. The paper describes the apparatus and test procedure, and reports data on various ores and mill products. Tailings known to have caused problems underground when used as backfill have shown heating rates of over 3°C/h. A preliminary hazard rating guide for backfill based on the known behaviour of several sulphide materials is presented.

Jan 1, 1981

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 G. Mucsi, J. Faitli, K. Bohács

"The authors developed an online tube rheometer to supplement a Netzsch MiniCer (Netzsch GmbH, Germany) stirred media mill in order to monitor online the rheological characteristics of the suspension and therefore the result of grinding during the process. Previously it was demonstrated that the above measuring system was working appropriately based on the preliminary tests. The product related stress model was applied for the evaluation of the grinding results. It was found that the suspension concentration and the change of the material properties during grinding, consequently the rheology strongly affects the grinding result, i.e. specific surface area, median particle size as well as specific grinding energy. The tested model limestone – water suspensions behaved Newtonian initially, then after a given grinding time their properties had changed and they become Bingham plastic. INTRODUCTIONStirred media milling now is a common practice to produce fine and ultrafine granular materials for different purposes. With an increasing demand of ultrafine powders for industries (Kwade, 1999), wet and dry ultrafine grinding has been increasingly used in various fields, such as minerals (Mucsi, Rácz, & Mádai, 2013)(Rácz, 2014), ceramic materials (Becker & Schwedes, 1999), pigments (Ohenoja, Illikainen, & Niinimäki, 2013), chemical products (Baláž et al., 2013), microorganisms (Kwade & Schwedes, 2002) and pharmaceutics (Afolabi, Akinlabi, & Bilgili, 2014). It is well known that suspension rheology affects the wet comminution of materials (He, Wang, & Forssberg, 2006a). The rheological behaviour of the suspension containing the ground particles might indicate the level of interparticle interaction or aggregation and therefore it is an important variable factor of the process control (Muster & Prestidge, 1995). The influence of the rheological behaviour of mineral suspensions on their grindability has attracted more and more interests and attention, especially on ultrafine grinding performance (He, Wang, & Forssberg, 2006b) (Bernhardt et al., 1999). However, there are still many issues concerning the machine and the process for the different applications. When grinding is effective and the particle size range decreases significantly, the circulating suspension is becoming typically non-Newtonian. The changed rheological behaviour and the increasing rheological material parameters can negatively affect the grinding efficiency; therefore it is an important issue. Ultrafine stirred media milling as well as solid-liquid two phase flow have been studied for a long time at the Institute of Raw Materials Preparation and Environmental Processing of the University of Miskolc. Regarding ultrafine grinding the research is focusing on the description of materials’ grindability (energetic aspects) both in wet and dry circumstances (Mucsi et al., 2013; Rácz, 2014). Concerning rheology, the three measuring pipes tube rheometer was developed decades ago (Faitli & Gombköto, 2015). So far many different solid materials from all over the world had been tested in this rheometer (Faitli & Gombköto, 2015). Main aim of these tests was to gain basic data for large scale hydraulic transport applications. Among the many stirred media mills there is a Netzsch MiniCer mill at the Institute. It was reasonable to combine the two fields together, and the goal of the research presented in this paper is to develop an online tube rheometer for the Netzsch mill and to carry out grinding and rheological testing simultaneously."

Jan 1, 2016

By Makarinskym F. M.

"This paper describes mechanical and operating modifications that were and are being made to current on-line flotation cells at Falconbridge Nickel Mines concentrators. Improved metallurgical performance and metal recoveries of some 3·4% over the past ten years are the end result of the modifications made. The paper acknowledges the contribution of operating, technical and maintenance personnel and the Company ""suggestion plan"" program. 1. INTRODUCTIONFalconbrirdge Nickel Mines Limited, incorporated in 1928 is a major product of nickel, copper,coba1t and other metals and minerals. The Canadian Nickel Division operating facilities in the Sudbury Area currently includes seven mines, two concentrators, and a smelter.For many years at all concentrators, improv0mcnts in metal recoveries have been continually under investigation. One area was to improve the flotation cell performance. This paper will deal with mechanical and operating modifications to the cells at the Strathcona and Falconhridge Ni-Cu sulphide concentrators, at the Sudbury Operations.One of the prime means to mineral beneficiation processing has been, and will continue to be, the basic froth flotation cell. The efficient operation of a flotation cell is the key to satisfactory metal selectivity and recovery. The essence of good design is simplicity. Changes to cell design can contribute to a significant improvement in metal recovery.Over the past 10 years, modifications to the flotation cells have contributed to an improvement of some 3-4” in mineral recovery. Providi11g tl1c initiative for improvements include operating, maintenance and technical personnel, as well as the employee suggestions submitted th1·ough the Suggestion Plan Program."

Jan 1, 1982