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By M. Bender, H. D. Goodfellow

"Belt conveyors, because of their low capital and operating costs and inherent flexibility in handling a wide variety of products, have numerous applications in the mining industry. With the increased emphasis on improving the workplace environment, dust emissions from belt conveyors at transfer and other points have become a significant problem for many applications.The paper reviews belt conveyor dust control technology and compares dust emissions from belt conveyor systems with other possible materials handling systems. Technical information on existing belt conveyor installations which have been designed to minimize or eliminate dust emissions is summarized. The important features of good design as well as the necessary input from operating and maintenance personnel are highlighted. The status of research and development work on dust control on belt conveyor systems on a world-wide basis is discussed. A proposed methodology for field measurements of emission factors from belt conveyor systems is presented. Data collected from such a test program can be used to establish a design basis for new dust-free belt conveyors.IntroductionBelt conveyors have proven themselves over the year s in the mining industry as a reliable and low-co st method of moving bulk material at high tonnage rates. Because of the above, as well as their inherent flexibility in handling a wide variety of products, belt conveyors are often called the ""workhorses"" of bulk material handling systems. For many processing plants, belt conveyors serve as the ""vital link"" in providing feed to the plant and the removal of the finished product. As would be expected, there has been considerable engineering effort in designing rugged and reliable belt conveyor systems.It is also well known that belt conveyor systems are a primary source of respirable dust emissions. The major sources are from the tail pulley where material is received and the head pulley where material is discharged, from the return idlers, due to the fine material attached to the return belt, and from the take-up pulley. It is usually considered that for dust particles less than 10 microns, these particles will remain airborne and thus can have a profound effect on the workplace environment."

Jan 1, 1982

By A. L. Holloway, N. M. Soonawala, L. S. Collett

"Since the late 1970s, a major R&D program has been under way in Canada to assess the concept of disposing of nuclear fuel wastes in deep plutonic rock. Atomic Energy of Canada Ltd . (AECL), a federally-owned corporation, has been given the responsibility of directing this research (Rummery et al., 1983).The Underground Research Laboratory (URL), constructed in a granite pluton 15 km east of Lac du Bonnet, Manitoba (Fig. 1) is a major component of the Canadian Nuclear Fuel Waste Management Program. A diverse geotechnical experimental program is being carried out during both the construction and operating phases of the URL. This program involves detailed geological mapping, rock mechanics and hydrogeology studies, and geophysical surveying, to characterize the rock mass surrounding the shaft, and it has been described by Simmons et al. (1983). As part of the construction-phase program, ground-penetrating radar (GPR) surveys are being carried out during excavation, in an attempt to delineate fractures both ahead of the excavation and behind the walls of the excavation. This paper presents the results of surveys performed during shaft excavation and describes a procedure for plotting the data.Ulricksen (1982) cites examples of radar surveys to evaluate surficial deposits, such as peat, sands and gravels, and cavity detection in subsurface hard rock. Fowler (1981) used radar for fracture and clay vein detection in coal seams.In Canada, pioneering work in GPR has been done by Annan and Davis since the mid-seventies (Annan and Davies, 1976). Their work concentrated on problems relating to permafrost in the Arctic ."

Jan 1, 1986

By W. H. Fertl, S. J. Pirson

Well logging techniques, as used successfully in oil and gas exploration, can also be used to give a detailed evaluation of drill holes through industrial mineral deposits such as sulphur. This paper describes the logging tools used gives the theory behind the well-log interpretation and discusses the application of the method in sulphur-bearing limestone and m more complex sulphur deposits.

Jan 1, 1970

By D. R. Boyle

"The basal type uranium deposits in south central British Columbia occur within unconsolidated, late Miocene fluvial paleochannel sediments that overlie major fault zones within the Okanagan Highlands Intrusive Complex. Prior to the formation of mineralization, paleovalleys containing host sediments were flooded by Pliocene valley basalts of the Plateau Basalt Formation. Five uranium deposits have been outlined to date, of which the Blizzard (4020 tonnes U) and TYee (650 tonnes U) are the largest. The basement intrusive complex underlying the deposits varies in age from early Cretaceous to Eocene and is comprised of quartz monzonite, granodiorite, Coryell monzonite, porphyritic granite and pegmatite.The mineralized host sediments comprise a complex sequence of interfingering conglomerates, arkosic sandstones and mudstones. Organic material is abundant in many, but not all, mineralized beds. Uranium mineralization is present in the form of uranous (ningyoite) or uranyl (saleeite, autunite) phosphates coating clastic grains and filling voids. Because of very strong reducing conditions related to large concentrations of marcasite and organic material, ningyoite is the only uranium mineral in the Tyee deposit, whereas the Blizzard deposit contains a more complex assemblage of minerals (saleeite, autunite, ningyoite). The observed paragenetic sequence of mineral precipitation in the Blizzard deposit (autunite-saleeite-ningyoite) indicates that the uranyl minerals, saleeite and autunite, are primary. Small amounts of Zn, Ni, Co and Mo have been introduced into the Blizzard deposit whereas Mo is the only non ore-forming element enriched in the Tyee deposit. Mn is the only depleted element in both deposits."

Jan 1, 1986

By C. E. McCoy

This paper will discuss briefly loader shovel requirements and then present a detailed survey of electrical drive systems to meet these requirements. The survey in general will deal with the various electrical provisions for shovel drives, along with the advantages and disadvantages, and in particular will discuss the MG set and static D. C. drive systems. Also included will be some insight into the requirements for optimum electrical power at the shovels.

Jan 1, 1979

By A. D. Misener

Introduction Temperature gradients have been determined for numerous locations in the Canadian Shield in connection with mining operations (1, 2, 12, 13, 14, 15). As part of a programme of geophysical studies of this region, some of these gradients were re-determined by the writer at locations where other thermal properties, specific heat, thermal conductivity, radioactivity, etc., were also to be measured. The ultimate object was to determine the heat flow to the surface at these locations. It was felt that the practice of determining heat flow from the temperatures and conductivities obtained in a single vertical bore hole (3, 4, 5, 6, 7, 8, 9) might give results which were appreciably divergent from the average for a considerable area. Particularly, it was thought that temperature gradients, whether obtained in a single vertical hole or from a number of random locations at various depths in a mine, might be subject to local variations and anomalies serious enough to render unsure any discussions based on them. The procedure followed in this investigation was to select a location where mine workings extended to considerable depth over a reasonably wide area. At selected depths below surface, horizontal drill holes extending into regions of undisturbed rock were located and resistance thermometers were inserted into these holes far enough to record the true rock temperature. An attempt was made to obtain a sufficient number of readings at or near any one level to give a representative coverage of the area selected. This ideal could not always be attained, but the large number of readings obtained for each are a does give a reasonably representative picture of the temperature conditions. These readings required much rime and movement of men and equipment underground . They could not have been obtained without the wholehearted co-operation of the management and considerable assistance from the personnel of the mines concerned.

Jan 1, 1949

By M. E. Grimes

"The future of the uranium industry in Canada during the next twenty years will be very dependent on political and social issues on a world scale. Technology, as such, will tend to be of lesser importance. Nonetheless, some technical changes can be anticipated.This paper deals with milling of uranium ore, leaving further processing and nuclear power production to specialists in these fields. An attempt has been made to look at uranium production technology in Canada in relation to that in other countries, and to draw interference regarding future changes that seem probable in the Canadian context. In particular, recent advances in mill equipment are considered.The chemistry of uranium and its relatively low concentration in most ores has been responsible for a completely hydrometallurgical approach to mill processing, and this should continue. In spite of little commercial success to date, pre-concentration of lower grade ores will be researched further in order that these ores can compete with higher grade deposits in Canada.The discovery of the relatively high-grade ores of the Athabasksa region will undoubtedly influence choice of mill processes and equipment. The potential effect on innovations is discussed"

Jan 1, 1986

By Owen Matthews

THE property of Cochenour Willans Gold Mines, Limited, is in Dome township, Red Lake area, northwestern Ontario, a hundred miles north of Kenora and close to the Manitoba border. 'Planes of Canadian Pacific Air Lines, Limited, serve the district daily, except Sundays, from Kenora, Ontario, and Lac du Bonnet, Manitoba, passengers being trans-ported from Winnipeg to Lac du Bonnet by car. Freight is handled by the Patricia Transportation Company. It is brought in from Hudson, Ontario, on the Canadian National railway, in summer by water and in winter by tractor trains over the frozen lakes. The first staking on the property was done during the 'rush' of 1926 and 1927 by William M. Cochenour, and on April 30th, 1928, a syndicate was formed, taking in claims of W. M. Cochenour and Dan Willans and H. G. Young. Surface trenching was carried on almost continuously until 1934. In October, 1932, Ventures Limited took an option on the property, and in December of that year they carried out an extensive diamond drilling programme, but considering the results did not justify further work, they relinquished the option. In July, 1934, further surface work was carried out under the supervision of W. P. Mackle and, on the strength of his report, Noah Timmins Incorporated took an option on the property and agreed to make an initial expenditure of $100,000 on development work. This was carried out under the direction of Hollinger Consolidated Gold Mines and included the sinking of a shaft to a depth of 165 feet, establishment of a level at the 150-foot horizon, and some 1,900 lineal feet of drifting and cross-cutting. The results obtained from this work were not considered of sufficient promise and the option was terminated in August, 1935. Mr. Cochenour then approached Alex Mackenzie and associates, and the present Company, Cochenour Willans Gold Mines, Limited, was organized on April 9th, 1936, and sufficient money was raised to continue operations. Under the direction of W. P. Mackle, the shaft was deepened and a second level was established at the 275-foot horizon; but, due to several adverse reports by outside engineers, it was found impossible to raise sufficient money to carry on the work and operations were suspended in December, 1937. In January, 1939, an agreement was entered into with Gold Eagle Gold Mines for the milling in their plant of some Cochenour ore. A total of 4,959 tons was treated, and the results were so encouraging that further finances were raised by C. A. Gentles & Company, of Toronto. Following further development in the mine, it was decided to erect a mill. Construction was started on September 1st and the mill was turned over on November 29th. The first gold brick was poured on December 23rd.

Jan 1, 1942

By Julie Hunt

Rimfire Minerals Corporation: early stage precious metal exploration specialists with discovery opportunities in partnership with major and mid-tier gold producers or prominent junior exploration firms. Mike Roberts, Senior Geologist

May 1, 2006

By Nichols. R. S.

"Surface coal mining production from Elk Valley and area in southeastern British Columbia began in 1913. Since 1970, five open-pit mines have been put into production: Westar Mining&apos;s Hanner and Greenhills Operations; Fording Coal&apos;s Fording River Operation; Byron Creek Collieries&apos; Coal Mountain Mine and Crows Nest Resources&apos; Line Creek Operation.ln 1983 these mines produced 14.9 million tonnes of raw coal at an average strip ratio of 4.9 bank cubic metres of waste to 1.0 tonne of raw coal. This is 70% of the estimated 21.1 M tonnes annual capacity .Multiple seams are recovered with truck/shovel and dragline equipment. There is a wide range of equipment types in use with a recent trend toward larger and more mobile equipment.Coal mining in Elk Valley involves advancing along strike in four steps: hangingwall waste removal; seam cleaning; coal recovery; and foot wall waste removal. Each mine is unique in its approach to these four steps but the truck/shovel methods can be categorized into three main groups: seam dips < 35 degrees as at Harmer, Fording and Greenhills; seam dips 35 to 50 degrees as at Line Creek; and seam dips >50 degrees as at Byron Creek. Dragline mining at Fording involves bath waste and coal removal by draglines."

Jan 1, 1984

By Andrew Artzer, Michael Moats, Jack Bender

Antimony and bismuth in copper electrorefining electrolytes can cause cathode contamination, leading to the careful control of their concentrations. This study examined the laboratory scale removal of bismuth and antimony from an electrorefining electrolyte using a solvent extraction mini-pilot plant. The ability of a proprietary phosphonic acid ester extractant (REX-2) in a commercial diluent was studied in a simulated commercial setting. Antimony and bismuth were both extracted effectively from the electrolyte (72% Bi and 70% Sb removed) and Bi was effectively stripped (92% Bi recovered) with 400 g/L sulfuric acid. A final strip solution was obtained from the SX circuit containing 0.36 g/L Bi, 0.043 g/L Sb, 1.3 g/L Cu, and 0.18 g/L As. Unfortunately, most of the extracted Sb remained in the organic phase. Following the pilot study, experiments were performed to examine the precipitation of bismuth from the aqueous strip phase and the removal of antimony loaded on to REX-2. INTRODUCTION For many years, antimony and bismuth have been some of the most problematic impurities in copper electrorefining (ER) (Bardwell & Lapee, 1933). Along with surface roughening, high concentrations of Sb and Bi can contaminate the copper cathode and precipitate at the copper grain boundaries. This drastically reduces the drawing ability of the metal (Bender & Emmerich, 2016). For these reasons, it is necessary to control Sb and Bi concentration in the cathode, which is done by controlling their concentration in the electrolyte. Conventionally, Sb and Bi concentrations are controlled by maintaining a proper As/(Sb+Bi) molar ratio in the anode and arsenic concentration in the electrolyte. Antimony and bismuth are removed during electrolyte purification using liberators (electrowinning cells) and/or ion exchange. Liberators treat an electrolyte bleed stream from the ER circuit and electrodeposit increasingly impure copper as the copper concentration of the solution decreases. Traditionally, first stage liberators reduce the copper concentration from ~45 g/L to ~15 g/L and produce saleable copper. Second stage liberators decrease the copper concentration to ~8 g/L (Biswas & Davenport, 1980) which results in contaminated cathode that is returned to anode production (Biswas & Davenport, 1980; Wang, 2004). Further electrolyte purification is not always required but third stage liberators can be used to reduce copper concentration below 2 g/L which results in significant removal of As, Sb and Bi and very impure deposits which are recycled to a smelter or used for As production. However, liberators do not have very high energy efficiency (Acharya, 2014; Ando & Tsuchida, 1997) and below 0.5 g/L copper, highly toxic arsine gas may form (Biswas & Davenport, 1980).

Jan 1, 2019

By O. E. Humeniuk, A. I. A. Salama, M. W. Mikhail

"The Western Research Centre (WRC) of CANMET operate a unique pilot plant facility where ongoing R&D on coal preparation and mineral processing is conducted. The pilot plant carries out two functions: coal preparation processing using state-of-the art technology and coal-liquid mixture preparation with intensive cleaning circuits that can also be used for mineral processing. In total, the pilot plant includes more than 30 different flowsheet options. The facility is dedicated to small and fine coal, and designed to be flexible and versatile.This paper describes the use of a pilot-scale facility as a research tool for process control development, fine coal beneficiation, development of coal-liquid fuels technologies, development of process models and testing and evaluation of new developments. The pilot plant is used to assist in resource development by evaluating and optimizing flowsheet selection, and producing sufficient samples for utilization tests. The facility is also an important tool for evaluating and testing samples from troublesome circuits of operating plants to find means to optimize and improve recovery, particularly of fines circuits.Detailed examples are given to demonstrate the role of a pilot scale facility in coal preparation R&D, coal industry development and optimization of coal processing operations. These examples include the development of heavy-medium cyclone computer control system, detailed evaluation of beneficiation of a coal deposit with high clay content, development of column flotation, and its role in fine cleaning circuits and treatment of ultra-fines in relation to intensive cleaning, the importance of testing coals in different processes, and cleaning processes influence on coking quality and other utilization applications. The potential of the facility for helping the mineral industry is also described."

Jan 1, 1992

By R. H. Nafziger

A novel process has been developed for preparing directly workable steel ingots from prereduced iron ore pellets by a two-stage process. The pellets are continuously charged into an electric arc furnace, where molten metal is separated from the gangue. The molten metal flows out of this furnace through a hollow nonconsumable graphite electrode immersed in a molten flux in an electroslag furnace. The molten metal solidifies on a continuously withdrawing base plate to form the ingot. A variety of standard carbon and alloy steel ingots . free of porosity , were produced using suitable decarburizers and ferroalloy additions. Some advantages of the two-stage process include: (a) consumable electrode fabrication is eliminated; (b ) no expensive deoxidizers are required; (c ) the uncontaminated electros lap flux can be reused; (d) energy consumption averages 25% less than in a conventional electric arc - electroslag operation ; and (e) the operation is continuous.

Jan 1, 1977

By D. R. Winchester

"I wish to thank you and your organizers for inviting me to address you at this point in time when we are all concerned for the future of the mineral industry in Canada.My topic ""Some Initiatives of Government Assistance to Industry Applicable to Mineral Processing"" is purposely limited in scope. To cover the entire range of initiatives in detail would take me all day, and at best, would be a mere recital of program titles, and a one sentence summary of the contents of the program. As you know, OREE or Regional Economic Expansion, is in the process of being amalgamated with elements of the Department of Industry, Trade and Commerce. We will become Regional Industrial Expansion or ORIE. If the name Canada Dry becomes popular, I don't think we will object as we hope to become a good mixer. The entire departmental thrust has been re-evaluated, and is in the process of being re-constituted to better serve the nation, and industry as a whole. Amalgamation of the industrial, trade promotion and marketing support skills of IT&C, with the regional development orientation and decentralization program delivery mechanisms of DREE, will, it is believed, provide better support to industry on a national and regional basis."

Jan 1, 1983

By K. G. Baxter, D. G. Dixon

The Sepon process plant utilises an autoclave to oxidize a flotation concentrate containing pyrite, residual copper minerals, and sulphur. The concentrate is produced from the residue of a preceding atmospheric copper leaching circuit. The function of the autoclave is to provide iron and acid for that atmospheric copper leaching circuit. The key issues in the operation of the autoclave are to maximise the production of acid and ferric ions and to avoid scaling issues related to sulphur balling in the autoclave. Scale control in the autoclave was examined using various dispersants and residue recycle without success. Operation of the autoclave at high temperature and high acidity addressed the scale issue through rapid oxidation of the sulphur and produced a ferric sulphate precipitate in the residue that could be re-leached to provide ferric iron. This paper presents the development steps followed, through batch and continuous piloting that resulted in an autoclave circuit design that addressed the above process requirements. Following definition of the process design basis, modelling of the autoclave operation was carried out to assist with engineering design. The model included thermodynamics and kinetics of oxidation of pyrite, elemental sulphur and covellite and also considered gas/liquid mixing, oxygen solubility as a function of temperature and solution composition, ferrous to ferric oxidation, gangue reactions with acid and precipitation/re-dissolution of basic ferric sulphate and alunite.

Jan 1, 2004

By Haofeng Xie, Lijun Peng, Xujun Mi, Xue Feng, Xiangqian Yin, Zhen Yang, Guojie Huang

The Cu/Al composite wires have been widely used in cable industry. Especially in the development of aerospace, the light weight character of wires is particularly important. The wires are fabricated by a drawing process and heat treatment. Mechanical and electrical properties are measured and analyzed. The bending behavior is studied by scanning electron microscope. INTRODUCTION Cu/Al composite is a typical bimetallic composite that has been used in plenty of fields such as automobile and aerospace. The composite has the advantages of excellent conductivity as well as low weight, which cannot be obtained from single copper or aluminum. Industrial products of Cu/Al composite include Cu/Al composite joints (Uscinowicz, R., 2013), Cu/Al bimetallic sheets (Li, X. et al., 2011), Cu/Al flat bar (Wu, Y. & Liu, X. & Xie, J., 2014) and CCA wires (Ahmed N., 1978). CCA wires refer to the composite wires that copper layer concentrically coated on the surface of aluminum core conductor, implementing solid combination of two metals on the interface and forming an integral. At present, the aircraft cable generally use copper or copper alloy conductor, which makes the wire in the aircraft occupy a considerable proportion due to the large density of copper. Therefore, the use of Cu/Al composite wires instead of copper wires for weight loss, is of great significance to the development of aerospace technology industry. Heat treatment is an indispensable procedure to improve plasticity during cold working process, which is of great importance to preparation of wires (Wang, Q. et al., 2008). During the heat treatment, the Intermetallic Compounds (IMCs) are inevitable formed at the contact area of Cu/Al due to the occurrence of diffusion (Lee, S. et al., 2012). According to the results of former researchers, kinds of IMCs were discovered. Antoine Gueydan (2014) identified the formation of three IMCs (Al2Cu, AlCu, and Al4Cu9) at the interface between copper and aluminum after thermal aging. IMCs have a significant effect to the properties of Cu/Al wires. Bending performance is a vital property for the actual application of wires. The brittle IMCs may create a stress concentration that can cause crack initiation during bending process. This work focus on the mechanical properties of Cu/Al composite wires after heat treatment. The effect of various annealing condition on mechanical and electrical properties are studied, in order to find the appropriate annealing conditions, which produce optimal combination properties of Cu/Al clad composite wires. Bending fracture of composite wires is discussed by morphology observation.

Jan 1, 2019

By W. H. Zieman

NORMAN WEISS, Milling Engineer, American Smelting• and Refining Company: The subject of the Forum on Rod and Ball Mill Liners is very fascinating, and there is no end of discussion when operators get together on grinding. However, the hypotheses and suppositions easily outrun the facts, especially when we •consider the inaccuracy of many reported observations. Still surprisingly small is the number of concentrators even reasonably well equipped to measure power consumption of each grinding mill, together with running time, so that data on this tangible factor, at least, can be obtained with precision. While the more elaborate devices of this nature, producing for each 24-hour period the total power consumption, average kilowatt hours per hour, short-term demand chart, instantaneous demand, and print-out, may cost in the neighbourhood of $2,500 per mill and may be difficult to justify, the combination of an ammeter, watthour meter, and running-time meter will cost only a few hundred dollars, so there appears to be little reason not to in-stall them in view of their numerous advantages.

Jan 1, 1959

By Horst Konig

This paper illustrates that, with the application of new processes, smaller steel plants using local raw materials can be economical and advisable. It also introduces the problems connected with the direct reduction processes, which use non-coking coal or gas as reducing agents, and which are employed in connection with conventional reduction to produce excellent results. Electric smelting is also discussed, and some practical examples of operating plants are given.

Jan 1, 1970

By I. Dymov, W. Phillips

A process has been evaluated, on a continuous pilot plant scale, to treat refractory gold arsenopyrite/pyrite concentrates. The process consisted of biological leaching to partially oxidise sulphides, followed by pressure leaching for complete sulphide oxidation and arsenic precipitation, followed by liquor neutralisation and cyanidation of the autoclave residue for gold recovery. This paper provides a brief description of the treatment flowsheet and discusses some of the main parameters and results of the process. During integrated pilot plant campaigns, it was confirmed that acceptable sulphide oxidation and gold extraction of 96-98% could be achieved by a two-stage oxidation with BIOX® (4 days total retention time) followed by PDX (40 minutes retention time at 220°C). Only partial arsenic precipitation was achieved in the autoclave, followed by complete precipitation by neutralization under atmospheric conditions. The overall process could be significantly simplified, and capital and operating costs reduced, with a flowsheet modification allowing all of the BIOX® liquor to bypass the autoclave directly to the neutralization circuit.

Jan 1, 2004

By W. J. Pearson

"""POTASH"" is a term applied to the compounds of the element potassium (K) and when used in agriculture and industry is ex-pressed in terms of potassium oxide (K2O), regardless of the actual com-position of the compound. When a chemical analysis is made of a fertilizer, the amount of K is deter-mined and then calculated to the equivalent amount of K2O. However, the compound K2O does not exist in nature. Most of the world's potash supply is derived from mineral deposits similar to those in Saskatchewan and New Mexico. However, there is some production from concentrated surface brines such as occur in Searles Lake, California; Salduro Marsh, Utah; the Dead Sea; and from well brines in Micl1igan."

Jan 1, 1960