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By Michael T. McCaffrey

The wide range of potential feed materials, process steps, and products in metallurgical facilities means that standard equipment might not be available to adequately meet the project technical and economic needs. Custom designed equipment should be considered only after rigorous research precludes purchasing standard equipment. However, the decision to use custom equipment introduces a new element of risk into the project. To manage the risk, custom equipment design should be developed through the same front end loading (FEL) phases as project development. If more than incremental development of custom equipment is required, appropriate test work or pilot trials are required to test key uncertainties. Important activities during custom equipment design include maintaining clearly defined performance objectives, conducting appropriate reviews, carefully crafting commercial and intellectual property agreements with design and fabrication partners, and assembling a multidisciplinary team with sufficient development expertise.

Jan 1, 2015

By M. Timmins

Campbell Mine operates a 100 tpd gold autoclave that treats sulphide concentrates at 305 psi and 200 °C. Autoclave feed consists of fresh pretreated concentrate, an acidic oxide slurry recycle as well as other high arsenic sources. The brickwork that is used to construct the five compartments of the vessel must be inspected and repaired periodically. Shutdowns are scheduled to inspect this brickwork and at times replace entire sections of the brick walls or lining. It also provides an opportunity to repair or replace other internal features such as agitator blades or oxygen spargers. Mechanics and contractors are scheduled around the clock to perform the maintenance requirements. There are many safety considerations and precautions that must be taken in order to protect the well-being of the workers and minimize damage to sensitive pieces of equipment. Heat, arsenic and lead contamination and confined space issues are just a few of the hazards involved. The following paper will describe how these safety concerns are addressed and will serve as a guide for future autoclave shutdowns.

Jan 1, 2004

By S. J. Schofield

INTRODUCTION ONE of the greatest and most interesting problems of economic geology is to discover criteria bearing on the persistence of ore in depth. It is a question which is very much to the fore in connection with many of our important mines in British Columbia, and, as is to be expected, it is a most controversial one. The present paper, summarizing the views of the writers concerning the possibilities, in some of the mining districts of the Province, for the persistence of commercial ore to greater depths than have been, or are at present, mined, is offered as a basis for a general discussion on the subject and to call attention to the need for renewed study and research on the problem. Sooner or later-at some depth or other-individual ore-shoots become impoverished and bottom. In many mines where this has happened, either at the same or at a lower horizon, another ore-shoot, which had no surface outcrop, has been encountered and has continued downward until it, in turn, has pinched out. The Kolar (Mysore, India) gold field, for instance, presents interesting examples of this recurrence of ore-shoots at depth (1). For many years these mines have been under the management of Messrs. John Taylor and Sons. On more than one occasion they have persisted in sinking or drifting on barren quartz or along a narrow fracture for many hundreds of feet before values were again encountered. Their earliest experiment in such bold development took place at a depth comparable to that at which most mines in British Columbia are considered to be bottomed. In the past, is has been concluded that the ores in British Columbian mines do not go below approximately 2,000 feet, and to that depth only in a few instances. Consideration of the depth to which ores have been mined in the Province appears to support this view. The figures shown in the accompaning table have been gathered from various sources and are approximate.

Jan 1, 1935

By David M. Parkes, George E. Davies

"Mathematically, the proposed formula is: ""Human Effectiveness + Technological Improvement = Success in the Nineties"". A brief review is made of geology, level of technology, management and labour situations, and range of production costs in coal producing countries. This comparison shows keen competition for Canadian coals, especially from the People's Republic of China, South Africa and Australia. Domestic competition comes from nuclear energy, hydro-electric generation, natural gas (if permitted) and eastern United States coal.The huge increase in the size and power of surface mining equipment in the last forty years led to modern large-scale open pit mining. While conventional truck and shovel operations will continue to be widely used, more continuous mining and conveying systems will be installed as pits become deeper and haul distances longer. Computer systems will become more sophisticated and their applications more widespread, leading to higher productivity and closer control of all operations and equipment performances and to partial or complete automation of certain operations.The underground revival will be driven by a new generation of mining people, cooperating to produce over 3 million t/y from 300 m longwall faces retreating over 3 km resulting in mine productivities of over 40 tonnes per man shift, as is already achieved in several mines throughout the world. Continuous operation using on-line control system will assist in consistent production with availabilities over 75%."

Jan 1, 1991

By Anton Gronningsater

AT the present time we hear a great deal about organization of labour, collective bargaining, workmen's councils, and company unions; about C.1.0. with its principle of vertical unions and A.F.L., largely based on craft unions; and about provincial and federal laws for protection of labour's right to collective bargaining. What we perhaps hear too little about is corresponding organization of the employers, although it recently is mentioned more frequently. I will only mention W. H. Davis, Chairman of the United States War Labour Board, who has had and is having plenty of experience in this field and has also studied labour conditions in Europe-in Sweden for instance. He has repeatedly expressed the opinion that where employer-employee problems are involved, a thing badly needed in America is organization of employers as well as employees to get some order in the present chaos. With this I agree. I believe a strong organization on one side necessitates a correspondingly strong organization on the other side; that has at least been the experience in the industrialized countries in Europe. I happen to be fairly familiar with conditions in Norway, where they have struggled with these problems for fifty years, and a talk on the history, development, and present state of employer-employee relations in that country might perhaps be of interest as giving a general picture of the development of such relations in the northwestern European countries as a whole. The talk was originally given to the Fourth Year students in Mining and Metallurgy at the University of Toronto. I have changed it somewhat to fit a different audience, but I hope you will make allowances if you now and then are reminded of the school auditorium. I will try to be as objective and factual as possible, but it is probably unavoidable that some of what is said is coloured by personal opinion.

Jan 1, 1943

By M. Buarzaiga

High-pressure acid leaching (HPAL) of nickel laterite ores typically extracts 95% of the nickel and 91% of the cobalt. Impurity elements in the feed, such as iron, aluminium and chromium, also dissolve and can be detrimental to downstream processes. Rejection of impurities within the autoclave is highly desirable. Aluminium and iron hydrolyze, and then precipitate in the autoclave leaving only small amounts that are subsequently removed by precipitation in a neutralization step. The concentration of dissolved chromium can range from 200 to 2000 ppm, depending on the feed composition. Chromium in the liquid phase, usually in the hexavalent state, introduces many problems and can limit refining options. For example, chromium poisons the organics in solvent extraction making SX an expensive option. Also, hexavalent chromium must be converted to the trivalent state before it can be precipitated along with iron and aluminium. Bench-scale work confirmed that mixing small amounts of carbon-base additives, such as coke, with the autoclave feed significantly reduced chromium concentration in the autoclave discharge without any detrimental effects on paymetals recoveries and selectivity.

Jan 1, 2004

By M. Board, R. Pakalnis, S. Seldon, R. Brummer

The Kidd operation mines roughly 10 000 tpd of copper and zinc ore from underground and employs about 700 personnel. In the late summer and fall of 1997, major movements in the proximity of the east wall of the Kidd open pit had been observed. The Kidd pit had been mined from 1965 to 1977 to depths of 260 m (850 ft), followed by subsequent mining by underground methods to current depths in excess of 1830 m (6800 ft). The No. 1 Mine (2600 Level to pit bottom) is approximately 90% extracted, with most of the remaining reserve between 2000 and 2500 levels. Although initial concerns centred on the stability of the pit walls, the potential ramifications of the movements to the underground were recognized and measures were implemented to ensure the safety of personnel as well as to minimize the potential damage to existing operations. In late October, damage to underground operations was observed as deep as the 2000 Level. In the final assessment, the global mobilized mass was a “wedge”-shaped hangingwall block extending from surface to about 610 m (2000 ft) below surface. The “wedge” boundaries are defined by a fault and shear zone which have continuous lengths in excess of 1070 m (3500 ft); its base by shearing through the host rock mass; and its eastern face by deep tension cracks (Fig. 1). Mined and filled excavations at the western face of the “wedge” allowed mobilization of a mass in excess of 30 M tonnes. Movements in excess of 75 cm (30 in.) per day were recorded on the surface stations that preceded the complete shutdown of operations on October 29, 1997. The evaluations in the days following the shut-down were centred on mitigation of immediate and future possible negative impacts on infrastructure and mining of the remaining No. 1 Mine reserves while ensuring the safety of the operators. This effort required the rapid assessment of the potential damage of the block movement on underground infrastructure, stope access, drainage and ventilation, as well as airblast potential due to the falling of a large block into the pit near the ventilation intake at the base of the pit. These assessments were presented in a previous paper (Seldon et al., 1999). In total, the lateral movement of the block on the ground surface was over 4.3 m (14 ft). This paper describes the detailed studies performed to understand the failure mechanism and to assess the impacts on future mining in No. 1 Mine.

Jan 1, 2000

By L. O. Thomas

THE Alaska Highway, in its course through British Columbia, traverses parts of two great physiographic divisions of Canada which are also distinctive geologically-the Cordillera in the western section and the Interior Plains in the eastern. The Cordilleran region in the portion of the Province with which this paper deals can be divided into four major northwest systems, known respectively from west to east as Coastal, Plateau, Cassiar-Omineca, and Rocky Mountains. The Coastal system consists solely of the Coast range except in the extreme northwest, where a part of the St. Elias range is included. The Coast range, characterized by mountains of great ruggedness,. is made up of an igneous complex of granitic rocks intruded chiefly as a great batholith. In places, spurs of these rocks extend into the Plateau heft, a partly mountainous tract largely occupied by quartzites, quartzose mica schists and their gneissic phases, and crystalline limestone with interbands and broad areas of chlorite, _hornblende, and sericite schists and bodies of intrusive granite gneiss-an assemblage of rocks known as the Yukon group. The Cassiar-Omineca system marks the divide between the Pacific and Arctic drainages. Its eastern boundary is well defined in the south by the Rocky Mountain Trench (see p. 229). The rocks of the system are, miainly, highly altered Palaeozoic sediments, but there are also Precambrian and Mesozoic rocks, the latter largely volcanic. The core of the system is granitic and there is evidence (see p. 221) to support the belief that it is of such a length as to constitute a batholith comparable to that of the Coastal system.

Jan 1, 1944

By Finley A. Campbell

"Nickel-copper sulphide deposits associated with basic rocks in the Quill Greek area and the White River area in the Yukon Territory have been studied and compared from the view-point of their general geology, structural geology, and the mineralogy of the ores. The relative amounts of the major constituents, magnesium, iron and calcium, and the minor constituents, nickel, cobalt and chromium have been determined spectrographically for two cross sections of the basic rocks at Quill Creek and one at White River. These data, along with petrologic and field evidence, were used to determine the sill and dyke-like character and nature of the basic intrusions. Loss on ignition is employed as a measure of the degree of serpentinization. The distribution determined shows that the serpentinization does not appear to have greatly influenced the inferred original distribution and lithophile associations of magnesium and nickel. The cobalt content may have been altered.The nickel content of the serpentinized peridotites ranges from an average of 0.36 per cent in one section to an average of 0.24 per cent in each of the other two sections studied. The cobalt averages 0.0038 per cent in the samples from the two Quill Creek sections and averages 0.0042 per cent at White River. These results have been compared with other available data.The sulphide ores are later than both the peridotite and gabbroic rocks and may be co-magmatic with them. There is no evidence in these areas to support an origin by lateral secretion; on the contrary, the alteration associated with the ores, the mineralogy and spatial relationship to basic and ultrabasic rocks, indicate the ores are derived from a basic magma."

Jan 1, 1960

By K. Lascelles

ABSTRACT Nickel compounds vary significantly in their toxicological properties, so it is critical that continuing studies to accurately quantify worker exposures consider the processing that accompanies refining nickel-containing materials. The Clydach nickel refinery, which has operated for more than 100 years, was the first nickel-producing facility to show a high risk for lung and nasal-sinus cancers among workers employed since it opened in 1902. Process chemistry and equipment have changed dramatically over Clydach’s history. This paper describes the processing evolution at Clydach with a focus on the propensity for aerosol formation and the forms of nickel in airborne dusts.

Jan 1, 2013

By C. M. Campbell

The Inconceivable Wealth propaganda goes on apace. Premier King, at Vancouver, has stated that we still have, untouched, natural resources, "beyond the wildest dreams." Principal Currie, in an address before the Canadian Society in New York said that Canada's resources, "are as yet merely scratched and it is not possible to compute her almost fabulous natural wealth." Mr. Meighen, in the last election campaign announced that, "under the providence of God, Canada is more richly endowed, perhaps, than any other country in the world." Four years ago a despatch was sent to Premier King "on behalf of" this Institute advising him that "Inconceivable Wealth" in minerals in this country was assured. This was made as a statement ~f "incontrovertible fact." Specifically, this despatch stated that this wealth was on such a scale that the mining industry would in the future lead all others in this country. This inventory is still in effect as far as this Institute is concerned.

Jan 1, 1926

By N. O. Lotter

The connection between mineralogy and metallurgical performance in a plant was recognised long ago (Gaudin, 1939; Petruk, 1976; Petruk and Hughson, 1977; Cabri, 1981; Petruk and Schnaar, 1981; Kinloch, 1982; Peyerl, 1983, Baum et al 1989 for example). The modern toolbox that we now routinely use for flowsheet development took decades to develop (Lotter et al., 2002; Baum and Lotter, 2004; Lotter, 2011 for example). Many workers contributed considerable time and effort to this overall mission of connecting sampling, mineralogy and mineral processing to integrate the flowsheet development activities. Certain key milestones marked this journey, such as Gy’s treatise on the sampling of particulate materials in 1979, which was later added to by François-Bongarçon, Pitard, Minnitt, and Holmes for example. The development of QEM*SEM by Gottlieb et al. of the MLA by Gu et al. constituted a huge leap forward in accuracy and mineral measurement capacity, as well as a reduction in standard errors of mineral characterisation. The advancement of the microprobe to an automated platform made a significant difference to detailed compositional mineralogy. This led to a strong position from which to draw meaningful processing implications from the mineralogical data. Reproducible flotation testing and reliable plant survey material for characterisation was dealt with by, amongst others, High Confidence Flotation Testing ( Lotter, 1995: Runge, 2010, and Bradshaw, 1997); and Statistical Benchmark Surveying (Lotter, 2005), with earlier prototypes which were steadily improved (Lotter, 1994; Restarick, 1976). The sterling work of Napier-Munn in engaging sound statistical methods with mineral processing led to the successful design and use of methods that could identify and quantify small recovery gains in plant scale trials. This history and present capability are reviewed, including leverage into asset management.

Jan 1, 2018

By Andre Panteleyev, Charels S. Ney, John M. Anderson

"Sam Goosly prospect, 22 miles southeast of Houston, B.C., was discovered in 1967 through geochemical reconnaissance. Soil sampling interpreted with respect to an east-to-west ice movement led to drilling targets.Mineralization is in a window of rocks thought to be Hazelton Group surrounded by Tertiary volcanic rocks and intruded by two stocks separated by about one mile. A westerly quartz monzonite stock is dated 61.1 m.y. and an easterly gabbro-monzonite complex is dated 52.5 m.y. The Tertiary volcanics are trachyandesites shown by the B.C. Department of Mines and Petroleum Resources to be in part extrusive equivalents of the gabbro, and they overlie Hazelton rocks uncomformably. Copper-molybdenum mineralization is sparsely developed in the westerly stock. Silver-copper mineralization forms an elongate west-dipping slab between the stocks in Hazelton rocks, which are continuously pyritized. The gabbro stock is not mineralized, but some dikes related to it are slightly so. Tertiary rocks are pyritized, but are not known to carry copper-silver mineralization. Hazelton rocks are divided into a lower conglomerate, an intermediate pyroclastic unit and an upper mainly sedimentary unit. They form a west-facing homocline. Coppersilver mineralization resides in the pyroclastic unit, mainly in a massive dust tuff through which are lenticular units of lapilli tuff. Well-mineralized rock is typically a breccia of light fragments in a dark chlorite-sulphide matrix. Sulphides are pyrite, chakopyrite and locally pyrrhotite, with very minor tetrahedrite, s phalerite and other sulphosalts. Rock alteration is predominantly a pervasive pyrite-sericite type, with widespread tourmaline, scorzalite, gypsum, ankerite and traces of fluorite. The most evident control of the copper-silver mineralization is the gross parallelism, over a strike length of 1.5 miles, to Hazelton strata, particularly a massive dust .tuff unit. In detail, mineralization crosscuts bedding and there is no appreciable banding within sulphides . A strictly syngenetic origin is untenable, but some initial concentration in a volcanogenic environment with subsequent modification by thermal processes seems likely."

Jan 1, 1972

By F. Doxey

Introduction Numerous papers have been written dealing with the construction and functions of, and the environmental conditions created by, Diesel locomotives. Therefore, it is not my intention to attempt to deal with these phases of Diesel transportation other than to make reference to them in ?relation to and in connection with actual operation. The rapid expansion of industry during recent years and the necessity of products being made available at competitive prices in home and world markets has made the demand for cheaper coal a very serious factor for the coal industry. This condition has meant each coal producing country looking into ways and means whereby greater productivity and reduction in cost could he achieved. Surveys made show that, in addition to face mechanization, savings, in some cases substantial, can be made in transportation. Ventilation The most efficient mines are in-variably the well ventilated ones, for it is true that, where there is good ventilation, there are usually good roads. These combined factors are very essential where Diesel locomotives are used. Good roadways and track allow speed, and good ventilation dilutes rapidly any disagreeable exhaust gases. Locomotive Development In the older types of auxiliary rope haulage, coal hauled per haul-age hand is usually very low.

Jan 1, 1951

By M. Pearson, L. Zunti

Pressure vessels in hydrometallurgy and many chemical process industries throughout the world require the use of specific lining systems to protect the parent vessel materials from corrosion and/or abrasion. Typically, these lining systems are required for processes that are corrosive and operate at elevated temperatures. Two basic lining system types arc: 1) refractory linings in conjunction with an impervious corrosion resistant membrane, and 2) metal-clad vessels consisting of titanium or other corrosion resistant metal bonded to a carbon steel shell. Operating conditions play a key role in selecting the type of lining system to be utilized for a specific application. Lining systems in turn have an impact on the process vessel size, which ultimately affects the capital cost of the vessel. The capital costs for each type of lining system must be considered for each application, as well as maintenance concerns, quality control, and delivery. It is clear that operating conditions play a key role in the final selection of lining systems utilized for specific projects based on initial capital cost, life-cycle maintenance costs, and overall service life. This paper will examine the fundamentals of each lining system, their inherent technical strengths and weaknesses, and present relative cost comparisons for each lining system as they apply to specific operating conditions and vessel sizes.

Jan 1, 2004

By S. H. Logan

Mr. B. Neilly: A week or so ago the Secretary was good enough to forward me an advance copy of this paper by Mr. Logan and it was suggested that I comment on it at this meeting. At that time I was not very certain that I would be here, so I committed my thoughts to paper. As a matter of courtesy to Mr. Logan, I sent him a copy of my proposed remarks and I would like to give you just what I sent to him. Appreciating fully Mr. Logan's ability and many sources of information, one naturally hesitates to question anything seriously set forth as his considered opinion. Neither does one of my political stripe like to accuse him of being too 'conservative.? However, in places his paper reminds me of another general manager of a Canadian bank. While I was still Secretary of the Ontario Mining Association, this general manager wrote asking for our forecast on the current year's mineral production, stating that he proposed to refer to such production figures in his annual address to his shareholders. The request was considered very complimentary to the Ontario Mining Association and, in my opinion, justified a great deal of serious study and effort. Finally, the estimate was prepared and forwarded, showing a modest increase over the previous year's total. Picture our surprise and chagrin on reading his address to find that he predicted not an increase but, if you please, a decline of over $10,000,000. Before I cooled off I wrote asking the basis of such a prediction and got a reply to the effect that men in his position had to be ultra conservative in picturing the future.

Jan 1, 1931

By C. V. Deutsch, O. Babak, J. G. Manchuk

High levels of geological heterogeneity occurring over relatively short distances pose a challenge to the unconventional open-pit techniques used in oil sands mining. There is strong motivation to mine selectively and minimize dilution and loss; however, the large equipment and high mining rate used to meet production targets tend to reduce selectivity. A numerical model is developed to account for geological complexity, mining equipment, regulatory criteria, and other operational parameters. This framework is used for more accurate forecasts, optimization of equipment, and other operational decisions. An example demonstrates the approach in light of Alberta Energy Regulator criteria.

Jan 1, 2014

By C. A. Pickles, K. Mackowiak, D. Gajonera

"Shake-flask oxidation tests were performed on Red Dog mine waste to study the initial dissolution behaviours of lead, zinc, and iron. The conditions for accelerated acid generation in terms of Eh and pH were determined. Each mineral behaved distinctly, with galena dissolving first, followed by sphalerite, then pyrite, although there was some overlap in behaviour. Iron was not detected in solution until approximately day 40 and was present at low concentrations. The experimental conditions and the theoretical model results indicated the formation of iron oxyhydroxides at low weathering times and jarosite at longer times.RÉSUMÉ Des tests d’oxydation par agitation en flacon ont été effectués sur les déchets miniers de l’exploitation Red Dog afin d’étudier les comportements initiaux de dissolution du plomb, du zinc et du fer. Les conditions entraînant la production accélérée d’acide en termes d’eH (potentiel d’oxydoréduction) et de pH (potentiel d’hydrogène) ont été déterminées. Chaque minerai se comportait différemment ; la galène a été la première à se dissoudre, suivie de la sphalérite, puis de la pyrite, mais un certain chevauchement des comportements a été observé. La présence de fer en solution n’a été détectée qu’après environ 40 jours et ce, à de faibles concentrations. Les conditions expérimentales et les résultats du modèle théorique signalaient la formation d’oxyde-hydroxyde de fer sur de courtes périodes d’altération atmosphérique, et de jarosite sur des périodes plus longues."

Jan 1, 2017

By M. Pearson, J. Irvine, L. Mercer, P. Lauzon

Severe service ball valve performance has a direct impact on the mechanical availability of high pressure oxidation and leach plants. The primary function of these valves is to isolate the autoclave for maintenance. Valve failure has historically contributed significantly to the maintenance downtime of these process plants. An understanding of the root causes of valve failures is the first step in increasing the reliability of the severe service ball valves. A rigorous failure analysis practice has been developed by Hatch for investigating refractory failures in furnaces and kilns based on Kepner-Tregoe methodology. The method has also been modified for valve failure analysis. From a root-cause failure tree analysis of each of the valve components, a list of all potential valve failure mechanisms was developed for ranking and evaluation, along with recommendations for further valve development. The purpose of this paper is to present the reader with the modified Kepner-Tregoe method and examples of this analysis.

Jan 1, 2004

By J. E. Amadi-Echendu, F. Stober, J. Ndlovu, L. R. Nelson

The Polokwane Smelter Complex (PSC) relies on a single 68MW high-intensity six-in-line furnace to smelt a planned 650 000 t/a dry concentrate to produce a platinum group metals (PGM)-bearing matte. As typical of a greenfields venture, considerable attention was paid to the project development and implementation stages of design, engineering, construction and commissioning. Somewhat unusual though, was the role of a dedicated multi-disciplinary "Operational Readiness" and support team, comprising the owners team and specialists from the furnace designer, HATCH, to effect a safe and rapid ramp-up to the design smelter capacity of 68MW. The challenges encountered in developing an effective partnership will be discussed. The modus operandi and roles of the "Operational Readiness" team during the design, procurement, construction and commissioning stages as well as that of the operational support team within the overall ramp-up objective will be presented. The "Operational Readiness" team was responsible for:

Jan 1, 2005