Search Documents

By J. C. Mitcheson

Mr. President, Mr. Mayor, Ladies & Gentlemen: IT GIVES ME great pleasure to have the opportunity, today, to speak on behalf of all the constituent. bodies of the Common-wealth Council of Mining and Metallurgical Institutions. For the past month we delegates have been right royally entertained across the length and breadth of Canada by Provincial Governments, City Councils, and other equally generous public organizations and private corporations. On this occasion, however, the President of The Canadian Institute of Mining and Metallurgy, our good friend Dr. H. J. Fraser, has been our host at the enjoyable reception preceding this Institute Luncheon, which luncheon was sponsored by our official host, The Canadian Institute of Mining and Metallurgy, one of our .constituent bodies.

Jan 1, 1957

By J. Janzen

The cost to supply ventilation may exceed 40% of the total mine energy cost for underground mines and is often higher for deeper mines. The goal of Ventilation-on-Demand (VOD) is to ensure that the required quantity and quality of air is supplied to underground mining crews and diesel equipment at the least energy expenditure (minimum cost). A VOD system may include control of surface fans (Supply & Exhaust), underground booster fans, auxiliary fans and automated regulators/dampers to regulate the flow of air with more control elements providing more value. Strategically located Air monitoring stations measure air quantity and quality and provide feed-back enabling control. The modular design involving controls, intelligent instrument and intelligent motor control centres coupled with a communication network allows the quick installation, commissioning and expansion of the system as the mine develops. The result is a very robust, flexible system while reducing maintenance costs and spare parts. This paper discusses the impact of sensors, installation and commissioning on advanced controls and provides solutions for in-field applications.

Aug 1, 2013

By M. du Plessis, D. F. Malan

"Crush pillars are designed to be in a crushed state whilst being formed at the mining face. The residual stress state of these failed pillars provides a local support function in mining stopes and is used in the majority of the intermediate depth South African platinum mines. On mines utilising crush pillars, the pillar dimensions are selected to achieve a width to height ratio of approximately two. This is not achieved in most cases as a result of practical mining problems and poor pillar-cutting discipline. Furthermore, pillar dimensions are seldom adjusted to compensate for the various factors governing crush pillar behaviour. The pillars should, however, be in a crushed state whilst being formed or whilst still in close proximity to the mining face to prevent potential damaging seismicity.An underground investigation was conducted into the behaviour of the crush pillars in a trial site on the Merensky Reef at Lonmin Plc. The aim of this investigation was to examine the mechanism of pillar crushing and the related rock mass behaviour. The underground test results and pillar behaviour are compared to a limit equilibrium model to investigate if the model provides a useful approximation of the behaviour of the crush pillars. This paper details some of the preliminary findings.INTRODUCTIONOn most mining operations, the design of crush pillars is based on trial and error. As the pillar strength is unknown, the pillar sizes are adjusted to obtain the correct behaviour. Crush pillar dimensions are generally selected to give a width to height ratio (w:h) of approximately 2:1, (Ryder and Jager, 2002). Several factors affect the behaviour of the crush pillars and in many cases satisfactory pillar crushing is not achieved. This results in a seismic hazard in many of the mines using crush pillars. If pillar crushing is not initiated whilst the pillar is being formed at the mining face, as the mining face advances and the pillars move to the back area of a stope, some pillars may burst while oversized pillars may punch into the footwall. If pillars are designed in such a way that they are fractured during cutting by the face abutment stresses so that the pillars will already have yielded and reached their residual strength, further compression of the pillars will be associated with an increase in load and stability will be ensured, (Ozbay and Roberts, 1988). The stiffness of the strata must therefore be greater than the post-peak stiffness of the pillar (Figure 1) or violent pillar failure and hanging wall instability will occur. The pillar design should be aimed at determining pillar dimensions for which the post-peak curve of the pillar is as flat as possible."

Jan 1, 2015

By M. E. Hurst

SINCE 1934 there has been a marked revival of interest in the Porcupine district, especially in the eastern portion of the area, where exploration on the property of Pamour Gold Mines has indicated the presence of extensive gold-bearing deposits. Owing to the prevalence of overburden and the limited amount of exploratory work that has been done, little information is available as yet concerning the distribution and structural relationships of the rocks in the area to the east of Porcupine lake. In order to throw some light on the structural conditions in this section, a brief discussion of the sequence and character of the formations in the better known, producing section of the camp has been included. It should be emphasized that this paper is a preliminary study and that, consequently, the conclusions expressed should not be regarded as final. The writer wishes to acknowledge his indebtedness to P. C. Benedict, whose study of the geological relationships on the Foley-O'Brien property has made possible a fuller understanding of the structure in the central portion of the area. The writer also wishes to express his appreciation of the information and facilities placed at his disposal by R. M. Macaulay and C. D. Stevenson, of Pamour Gold Mines, and by A. Bell, of Noranda Mines, Limited.

Jan 1, 1936

By Jochen Petersen

This paper gives an overview of the various strands of postgraduate and undergraduate training offered in the Department of Chemical Engineering at UCT. Since 2003 the Department is offering a formal postgraduate MSc programme in hydrometallurgical engineering aimed especially at graduate work-based engineers, with 5 weeks of intensive course work plus a research dissertation on a work-related project. This programme has now run 5 times over the years and produced some 20 degrees. The paper reflects on the experiences with running the course, especially the difficulties experienced with supervising industry-based external students. Furthermore, through the Department a graduate training program is offered for all junior metallurgists at a major South African minerals company. This 2-year program, which is currently on its 12th cohort, offers 1 or 2 week intensive blocks of course work alternating with longer stints where the candidates are based at various operations. Although primarily focussed on minerals processing, it has a significant element of hydrometallurgy in it and in recent years an advanced hydrometallurgy stream has been introduced. The paper reflects on the development of the program over the years, the benefits it has provided to the company as well as some of the challenges that remain. Finally the paper gives an overview of hydrometallurgy related undergraduate and research-only postgraduate MSc and PhD projects at the university. Some emphasis is placed on the recently launched South African Minerals and Metals Research Initiative (SAMMRI), a joint government-industry programme to support university-based research in the area of applied metallurgy.

Jan 1, 2014

By R Chandramohan

Comminution is the science of size reduction of brittle materials. It is integral to mineral extraction and is one of the most energy intensive processes in the mining industry. There are a number of tests used to quantify the strength of ore, which are then used to size the AG / SAG mill in circuit design. The calculated energy utilized for breakage in these devices is based on the assumptions that the materials treated are of average shape and that the processing equipment is designed to break the ore as efficiently as possible under the given operating conditions. In drop weight tests, it was found that shape significantly influences the measured rock strength. Controlled experiments with variations in blends of rock shape show that mill throughput increases with the addition of weaker shaped rocks.

Jan 1, 2012

By J. Gogal

Cameco's Cigar Lake Operation (CLO) started commercial uranium ore production in 2015. Initial mining was focused in areas of the ore body with relatively low concentrations of elements of concern (EOCs). As mining progressed into areas of the ore body that were richer in EOCs, some statistically significant behavior of certain analytes was noted in the water treatment circuits. It was ultimately found that the CLO ore body natively hosts numerous alkyl arsine compounds in addition to inorganic arsenide minerals. The alkyl arsines were found to be recalcitrant to typical adsorption on ferrihydrite, with the degree of recalcitrance associated with the degree of alkylation. A number of changes to the process circuits and water balance were performed and planned in order to inhibit the transport of alkyl arsines from the ore stream into the process water stream, and to optimize the overall site water usage. In some instances, the interactions of equipment in conjoined circuits of the process had controlling effects on the behavior of the overall circuit. Work continues to iterate upon the capital design features in order to further tighten the water balance, and to optimize water usage and operating costs.

Jan 1, 2020

By W. B. Timm

Introduction In preparing this paper on Recent Developments in Gold Milling Practice, the idea occurred to me that possibly the best way to deal with the subject would be to take you in thought on a visit to the principal gold mining camps of the Dominion, starting at the east and finishing up in the west, and noting, as we go, the outstanding improvements that have been made in the last few years in the practice of gold milling. Before beginning this tour, I desire to emphasize the debt this country, and particularly our mining industry, owes to that body of trained and experienced men, little heard of, but who, working quietly on their problems, are responsible for these improvements. The metallurgists, to whom I refer, have solved many difficult problems for the mining industry, in connection with the treatment of our complex ores; for instance, the silver-cobalt ores of the Cobalt district, the gold ores of the Porcupine district, the gold-telluride ores of the Kirkland Lake? district, the copper-gold ores of Noranda, the arsenical-gold ores of the Beattie mine, the copper-zinc ores of Flin Flon, and the lead-zinc ores of Kimberley. In doing so, they have maintained the high technical standards of the profession, and the practices thus evolved are noteworthy for their high degree of efficiency. When the price of gold increased from $20.67 to $35.00 an ounce, what had formerly been thought to be a low tailing became almost an ore, so that the metallurgists are now busily engaged upon the problem of putting this railing back in its proper place of being a tailing once more, or from its value, at the present price, of anywhere from 50 cents to a dollar or so per ton, to a few cents per ton. Owing to the changing prices of the metals in the world's markets, still greater improvements in metallurgical practices are imperative. An important contributory factor towards improvement in ore dressing is the aid furnished by the microscope in the examination of ores and mill products. By making possible the determination of the mineral constituents of the ore, their association, and grain size, it gives the investigator a knowledge of his problem, before he does any actual test work. In the Mines Branch laboratories at Ottawa, its use has enabled us to predict how an ore should respond to various methods of treatment.

Jan 1, 1935

By Timothy W. Ellis, Abbas H. Mirza, R. David Prengaman

Recycled lead, i.e. material produced by the recycling of lead-acid batteries, has become the primary source of lead in much of the world. This has been important to the recycled lead industry as other uses have dwindled, e.g. lead based pigments, chemicals, fuel additives, solders and CRT glasses. Presently, battery manufacturing accounts for greater than 85% of lead consumption worldwide while recycled lead accounts for approximately the same market share of lead supply. Battery manufacturing and production of recycled lead are intimately coupled. In 2007, of all the industrial base metals, lead from lead-acid batteries had the highest recycling rate in North America at greater than 95%. In this paper we will review some of the processes and technologies used in a modern lead acid battery recycling facility, and how recycled lead has become the material of choice for battery construction through the development of a recovery and refining process that exceeds the industry requirements. We will also briefly review an advanced air emissions treatment system in a modern lead recycling plant that demonstrates the feasibility of a new maximum available control technology (MACT) for secondary lead smelters.

Jan 1, 2011

By F. J. Alcock

The Appalachian region of Canada comprises the three maritime provinces; Nova Scotia; New Brunswick; and Prince Edward Island; and that; part of the Province of Quebec lying south and east of Logan's fault. This; major thrust runs in a gently curving line from lake Champlain to Quebec; city and thence down the valley of the St. Lawrence to pass between Anticosti; island and Gaspe peninsula. To the northwest lies the St. Lawrence; Lowland division of the Interior Plains geological province; a region underlain; largely by early Palxozoic strata; which for the most part lie horizontal; or with low dips; where faults occur they are predominantly of the normal; type; and only locally are the beds cut by intrusive rocks. To the southeast; on the other side of the fault zone; an entirely different set of conditions is; encountered. There; Lower Devonian and older strata stand at high angles; are sheared and thrust faulted; and are intruded in many places by granitic; igneous bodies. The present paper is designed to outline briefly the geological; and structural history of this geological province and to emphasize; the part that structural conditions have played in connection with mineral; deposition.

Jan 1, 1954

By D. Hu, L. Matzar, J. Hampton, M. Gutierrez

Nanodarcy permeability is common in many oil- and gas-bearing formations requiring unconventional stimulation technologies, such as hydraulic fracturing (HF), which can connect the isolated hydrocarbon-rich pores with a wellbore through induced fracture networks. Even though a dense induced fracture network is capable of accessing economic amounts of hydrocarbons, much of the rock between and very close to the fracture network is still un-accessed and contains extremely low permeability. Inducing fracture networks into brittle rock can create large amounts of micro failures in surrounding regions that are not connected to the wellbore, as can be seen in Fig. 1(a) from the very wide acoustic emissions (AEs) cloud associated with a narrow fracture generation. It is possible in certain types of rock to increase the effective matrix permeability in localized regions based on the damage associated with the surrounding hydraulic fractures and subsequent high stress concentrations along localized pre-existing potential failure zones. To study this problem, laboratory HF tests were performed at true-triaxial stress state in brittle crystalline rock while monitoring AEs. The AE associated with HF was analyzed for source parameters using the moment tensor inversion method called Simplified Green’s Functions for Moment Tensor Analysis (SiGMA). Using the moment tensor for each individual AE event, the mode of failure was determined. Crack slip directions and crack face normal directions were also found, along with the relative volume of individual micro failures as well as a damage parameter. The associated source parameters were used to classify differing regions of damage in the sample induced from HF and correlate these regions of differing damage to the effective drainage region. Shown in Fig. 1(b) is a near-wellbore (NWB) region that contained three times larger average relative volumetric deformation of individual tensile AE events than the average tensile AE event volume from the entire sample. Because of the large difference in micro fracture volumetric deformation for the NWB region compared to the entire sample, predictions of HF induced damage must be included in reservoir drainage predictions.

Jan 1, 2015

By R. Gutray, J. E. Grainger

This paper deals with the use of a cement-deslimed mill tailings mixture for a scraping floor in cut-and-fill stopes at Madsen Red Lake Gold Mines Limited. It describes the mixing and placing procedures and the precautions used with respect to the floor while mining in the stopes. Details of the mix are presented, and advantages and disadvantages discussed. The paper concludes with a brief outline of the costs.

Jan 1, 1966

By R. B. Anderson, N. J. Sherren

The mining equipment at the Scully Mine, Wabush, consists of approximately twenty-five large haulage units, eight large dozer-loader applications and seventy other related pieces of service and maintenance equipment. This equipment is operating in sub-Arctic conditions. This pa-per presents a description of the tire maintenance procedures in use here and discusses the tire troubles that are being encountered and the methods of dealing with them.

Jan 1, 1969

By R. W. Wein, L C. Bliss

Northern ecosystems are dominated by a harsh physical environment which dictates a need for biological adaptation. As yet, it is unknown just how these adapted plants and animals will tolerate industrial development. Our work, sponsored by university, government and industry, is part of an effort to evaluate this developmental impact. Our present studies and the results to date will be discussed. Other problems to which the environmental student may address himself in the future to ensure against environ-mental degradation will be suggested.

Jan 1, 1971

By E. Thomson

This type of microscopic investigation, although still in its infancy, has already found practical applications in several different phases of mining activity. The study of the transparent minerals in rocks, by means of the ordinary petrographic microscope, has for long been a very useful supplement to observations in the field, but the opaque minerals, until recently, have had to rest content with a more or less superficial determination with the hand-lens or the blow-pipe. In a great many cases, particularly where the association of metallics has been somewhat complex, this has been entirely inadequate, and the determination of these opaque minerals under the micro- scope, has opened up a new field of scientific investigation that bids fair to surpass, in practical value at least, the micro-scopic determination of the rock-forming minerals. As the details of this kind of microscopy are possibly not entirely familiar to all mining men, it might be well to outline them very briefly before dealing with the practical directions in which this method may be applied. The ordinary petro-graphic microscope, with but one extra attachment, will serve for this work. A small reflecting device, called a vertical illuminator, is inserted immediately above the objective lens. This reflects the light down to the surface of the specimen and from here the light is directed up the middle of the microscope tube to the eye. As it is desirable that the maximum amount of reflection should be secured from the surface of the section, it is first polished and set in a position perpendicular to the vertical axis of the microscope.

Jan 1, 1924

By H. Clare Horwood

"Fractures and fracture zones containing veins and stringers of auriferous quartz in a quartz porphyry dyke are the principal structural features at the Howey and Hasaga gold mines. The 'break' containing the dyke was produced by a force from the northwest, the fractures in the dyke by compressive stress from the west.Both mines are in the north-central part of Heyson township, in the Red Lake area. They lie close to the southeastern side of the Dome granite stock. The Howey mine exhausted its ore reserves and ceased operations in November 1941. The Hasaga mine is producing at the present time (June, 1946).Mineralization was first discovered in the dyke in 1925 by the Howey brothers. Lorne Howey's discovery, which became the Howey mine, came into production in April, 1930; Ray Howey's find, which is now the Hasaga mine, started production in November, 1938.The total production from the Howey mine was 421,324 oz. gold and 144,253 oz. silver from 5,158,376 tons of ore hoisted ( 4,319,331 tons milled) during its 11 years of operation.The total production from the Hasaga mine from November, 1938, to December 31, 1945, was 124,434 oz. gold and 51,009 oz. silver from a total of 901,098 tons hoisted (721,361 tons milled).GENERAL GEOLOGYThe porphyry dyke containing the orebodies at the Howey and Hasaga mines lies a short distance southeast of the contact of a granite-granodiorite mass known as the Dome stock. The dyke fills a fracture trending N.65°E. in a tongue of Keewatin volcanic breccia that extends in a rather irregular manner into an elongate intrusive stock of dioritic rock known as the Howey diorite. The accompanying table presents the geological succession."

Jan 1, 1954

By M. Reda

Because of the adverse environmental effect of Chromate, Molybdate ions had been investigated as replacement for Chromate and the results had shown not to be encouraging. Film deposited from peroxopolymolybdate (from reaction of Molybdenum meta, with excess Hydrogen Peroxide), are more robust than that deposited from molybdate solutions. This was shown to be due to higher fraction of Mo (IV) and Mo (V) that form from Mo (VI) in the peroxopolymolybdate deposited film than the film deposited from Molybdate solutions. The peroxopolymolybdate film contains 40% un-hydrated molybdic acid, tetraperoxodimolybdate and tetra peroxo tetra molybdate. The protective properties of peroxopolymolybdate were shown to be due to the effectiveness of the un-hydrated molybdic acid.

Jan 1, 2010

By G. E. Wood

Steep Rock Resources Inc. owns a calcite quarry property at Tatlock, Ontario, and a calcite processing plant at Perth, Ontario. The Tatlock marble deposit forms part of an extensive series of carbonate rocks of the Grenville Geological Province in the Precambrian Shield of southeastern Ontario. The deposit is very unusual, if not unique, in the Grenville area in its combination of characteristics of large size, whiteness, high calcium content, low magnesium and silica contents, and scarcity of accessory minerals. A major expansion of the fine grind products capacity of the plant was undertaken in 1982 and came on stream in 1983. The expansion provides important operating benefits at the plant: greater flexibility as to the product mix and reduced dependence on the single grinding mill previously in place. The expanded facility consists of prima,y and secondary crushers, a rotary drye,~ a screenhouse producing a range of screen separator grade products, an airswept Raymond Mill, and a pebble mill with integrated air classifiers, product storage bins, bulk, semi-bulk, and bagged product shipping capabilities, road and rail access, and a substantial product warehouse. The expansion was designed to be compatible with a move into ultrafine calcite production, and is capable of supplying the anticipated sales growth within its market area during the next 5 years. Products are exceptionally white, with good chemistry, low abrasion, and consistent quality. Markets range, according to product particle size, from pre-cast concrete aggregate to fillers for coatings, plastic pipe, and compounds.

Jan 1, 1984

By A. Sutherland Brown, Stuart S. Holfand

"The Northeastern part of the Cariboo district lies in the big bend of the Fraser River between Quesnel and McBride. The area shown on Figure 1 extends from just west of Wells to Isaac Lake, about 30 miles across the regional strike of beds.Topographically the area extends from the moderately well dissected Interior Plateau in the west through a transition zone to the fully dissected Cariboo Mountains in the east.The area is an important source of lode and placer gold. The Cariboo Gold Quartz and Island Mountain lode-gold mines have produced more than 32 million dollars in bullion since 1932. Placer-mining has probably produced an equivalent or greater amount, although only 15 million dollars is officially recorded because accurate statistics. were not kept until fourteen years after the origiiaal gold rush of 1860.The regional structure of the Barkerville district was summarized by Lang in the Jubilee Volume (1948, pp. 141-149). Since then a large amount of detailed and areal mapping by the writers has expanded the information available and made necessary a complete revision of the regional geology. Much of the information summarized in this paper, together with a full discussion of the revisions, may be found in British Columbia Department of Mines Bulletins, Nos. 34 and 38, but other information is as yet un-published.Rocks of the Kaza group are exposed in the core of the Lanezi anti-clinorium between Spectacle and Isaac Lakes. The main part of the group is composed of greenish micaceous greywacke and greenish schist with knots of garnet, biotite, or both, and minor amounts of pebble conglomerate. The upper 1,000 feet is composed of white to brown quartzites and brown phyllites. Altogether, about 6,000 feet of the group is exposed. 1t is of latest Precambrian, i. e. Windermere, age."

Jan 1, 1949

By D. Campbell

Mining activity is increasing in northern boreal and subarctic regions of Canada. This is the case in the far north of Ontario, especially in and near the Hudson Bay Lowland (HBL). De Beers Canada opened the Victor diamond mine in the centre of the HBL in 2008, and advanced exploration and impact assessments are occurring to the west in the ?Ring of Fire? for ferrochrome, nickel/copper, iron/ vanadium and platinum-group elements, making it one of the richest mineral finds in Canada in recent years. However, the HBL is also a near-pristine, sensitive environment. Its peatlands forms the third largest wetland in the world and are globally important stores of terrestrial carbon. Human populations in the region are sparse, consisting almost entirely of First Nations communities. Local First Nations also have a strong land ethic and greatly influence mining developments. Through formal agreements, they have insisted on a gold standard for environmental management, including a small mine footprint and the return to representative native ecosystems after mine closure. However, knowledge on the revegetation of subarctic and northern boreal ecosystems is limited. Here, we are conducting research at the Victor mine to develop gold standard protocols for the revegetation of disturbed peatlands and mine waste uplands and present a summary of results. We first tested existing protocols for peatland restoration from southeastern Canada. We collected peat-forming plants from nearby muskeg, spread them sparsely over disturbed peatlands and applied a light phosphate fertilizer, but unlike southern protocols, no mulch appeared to be required to produce a representative cover of peat-forming plants within three years. A bigger challenge is the reclamation of uplands made of mine waste back to representative ecosystems. We first characterized reference conditions for uplands in the HBL, which are scarce in the region. Nearby natural uplands were divided into two classes, interior uplands and uplands along river valleys. Multiple parameters were examined at these sites including soil development, bulk density, soil chemistry in the rooting horizons, plant cover by stratum, plant species composition and dead wood. The mean condition and, more importantly, the range of these parameters allow us to set broad targets for progressive reclamation, which will facilitate success. Finally, we characterized local upland plant species through their functional traits to determine their likely abilities to colonize, grow and contribute to ecosystem processes. A classification of species by these simple functional attributes will help restoration managers to select candidate species to meet different goals at different successional stages (i.e. good versus poor dispersers or establishers). Research into these protocols remain in the early stages, but show promise that gold standards can be achieved to ensure that mining wastes can be reclaimed to productive ecosystems.

Aug 1, 2013