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By Theo. Koulomzine

"The property of Consolidated Central Cadillac Mines, Limited, consists of 1,103 acres formerly held by Central Cadillac Mines, Limited, and Wood Cadillac Mines, Limited. Both mines have been partly developed to depths of 565 and 1,000 feet respectively, and from 1939 to 1943 they produced gold, with small amounts of silver and tungsten, having a total value of $2,208,528 from 377,489 tons of ore. The average grade of the ore was $5.85 a ton . Less than 10 per cent of the ore hoisted was discarded by sorting. New development work, carried out since the former Wood property has been purchased by Central Cadillac, has shown that the tonnage indicated by mine workings and diamond drilling exceeds 2,000 tons per vertical foot.The property lies between the claims of Kewagama Gold Mines, Limited, and Pandora Cadillac Gold Mines, Limited, and straddles the Cadillac 'break' for a length of nearly 1 ½ miles. The main workings are 1 3/4 miles east of the well-known O'Brien gold mine.GEOLOGYOutcrops are very scarce, with none at all of the most important horizons, so that the general geology shown in Fig. 1 is deduced mostly from underground workings and diamond drilling. Fig. 2 is a vertical cross-section and Fig. 3 a longitudinal section through the ore zone.The ore lies within a belt of Blake River volcanics which is approximately 600 feet wide and is flanked on the north and south, respectively, by Cadillac and Kewagama sediments. All the formations have a nearly vertical attitude. The Blake River belt consists essentially of well sheared volcanic tulfs, but associated with these in the northern part are a number of bands of iron formation and the central part, to a width of 100 feet, is occupied by talc schists, making the Cadillac fault proper. Intruding the volcanics south of the Cadillac shear zone are dykes of two types- finegrained aplite or quartz albitite, and porphyry; both consist essentially of albite and quartz and are distinguishable only by the grain size. They have the general east-west trend of the formations they intrude."

Jan 1, 1954

By D. W. Bacon

Plant process optimization programs are often costly, both in technical effort and loss of production. Evolutionary Operation or "EVOP" is a mode of plant operation consisting of controlled cyclical changes in process conditions by which information is provided concerning potential process improvements while both volume and quality uniformity in production are maintained. Its conceptual simplicity and low cost of utilization have led to successful adoption in a variety of industrial manufacturing operations. This paper is an expository account of basic EVOP theory, the problems encountered and the organization required in applying it to a processing plant. Illustrations are provided which indicate the payoff that can result.

Jan 1, 1967

By Colleagues from Process and Operation departments, Guy Chevalier

"QCM's pellet plant, located in Port-Cartier, Quebec, produces up to 8.6 million tons of iron ore pellets annually. Four different types are produced: three for blast furnace operations and one for direct reduction furnaces. The paper presents the scientific approach that led to the installation of new process equipment to improve the reducibility of direct reduction pellets (DR pellet). The findings, the equipment selection and some post start-up modifications are presented.This low silica DR pellet is used in Midrex and HyL shaft furnaces. A good DR pellet has to meet strict chemical, physical and metallurgical specifications. An important metallurgical property is its ability to release oxygen when exposed to reducing gases. Considering that the market for DR pellets is expanding and being aware that reducibility is critical for our clients, a program to improve the latter was undertaken. Test work showed that one factor which has a negative effect on reducibility is the proportion of particles larger than 75 microns. Knowing that the best way to reduce the amount of coarse particles was to close our open grinding circuits, we began evaluating the most suitable classification equipment applicable to our process operations. We settled on hydro-classifiers based on their very sharp cut and their low operating costs. In light of the hydro-classifiers performance it was also decided to replace the hydro-cyclones of an already closed circuit.INTRODUCTIONAt the Québec Cartier Mining pellet plant, continuous improvement programs are aimed at increasing levels of consistency and improved chemical, physical and metallurgical properties. This is being accomplished while still maintaining pellet plant production volumes to satisfy market demands.QCM produces three types of pellets for blast furnace use: acid pellets, designated as ""BHF"", fluxed pellets, designated as ""BAF"", and low silica fluxed pellets, designated as ""BSA"". For direct reduction, a low silica acid pellet or DR pellet, designated as ""BBS"" is produced. This low silica DR pellet is used in Midrex and HyL shaft furnaces.The demand for DR pellets has been increasing during the last few years and is believed to continue so in the future. Wanting to be present in this growing market QCM found that it would be essential to work at improving its DR pellets quality. Efforts have been focused on improvements in three areas: SiO2 reduction, elimination of sticking and increasing reducibility. Improvement programs have begun with laboratory research followed by plant trials and full-scale implementation as a cooperative effort among QCM, COREM, and key customers."

Jan 1, 2002

By Robert F. Shurtz

This paper discusses and compares methods of statistical analysis of the information relating to the evaluation of an asbestos deposit. From a study of 10-ft. lengths of drill core, the separate effects of visual evaluation errors were determined, as well as the deviations between evaluators and the deviations produced by a slight displacement in the center lines of the check drill holes. The importance of careful statistical analysis of such information is stressed.

Jan 1, 1966

By John C. Leighton, C. O. Brawner, Doug Stewart

"Despite the availability of established, sophisticated methods for planning and designing stable slopes in rock, comparatively little attention is usually paid to the problems of carrying out the excavation. Blasting should be carefully planned to obtain optimum fragmentation as well as steep, stable working and final pit walls. The principal difficulty facing a blast designer is the lack of prior information about the many critical blasting characteristics of the rock mass. The common practise of trial-and-error lasting will eventually lead to a suitable program, but must be repeated time after time in variable geology. This frequently results in many blast-damaged slopes. Recent research indicates that monitoring drill performance will yield a Rock Quality Index which correlates to a Powder Factor value. The drilling can provide a continual supply of data, reflecting changes in the rock mass which enables the selection of an economical powder factor.IntroductionWhen planning to excavate a large-scale rock slope, engineer s will generally spend considerable effort to produce a safe, feasible and economical design. Much time will usually be spent on the field map ping, 'structural geologic studies, surface and subsurface hydrology, determination of strengths and effective friction angles of discontinuities, and finally checking stability with the aid of mathematical and analytical models. If the rock cut is to be along a transportation corridor, the prime justification for this time and effort is to produce a clean, stable slope which will be safe for those travelling or working beneath it. For the walls of an open-pit mine, there is the additional economic incentive to maintain the steepest stable slope angle for the minimum stripping ratio (Stewart and Kennedy)."

Jan 1, 1982

By E. Fried

Cemented paste backfill (CPB) is an innovative tailings management method that consists in returning considerable amounts of mine tailings into the underground mine openings. The filled stopes thus participate to the ground support that allows maximizing orebody extraction and a safer environment for the mine workers. There are also significant environmental advantages of using CPB. Indeed, up to 50% of the concentrator tailings can be backfilled, leading to a smaller volume of problematic waste materials to be managed at the surface. Once the CPB is placed, or when the mine is flooded at its end-life, the backfill is subjected to underground water flows that may leach and spread the pollutants (mainly metals, sulphates, and acidity) which can contaminate the underground waters. The aim of this study is to characterize the leaching properties of CPB material and to identify the cement phases that ensure the metal fixation. A laboratory procedure was implemented consisting in the preparation of various paste backfill mixtures using sulphide-rich and sulphide-free materials, different types of binder, and mixing waters having various sulphates, copper and zinc concentrations. After 90-days curing time, the samples were submitted to column leaching tests. The CPB materials were flushed each day with 100 ml of deionised water during 100 days. The collected leachates were then analyzed for pH, Eh, electric conductivity and chemical composition. For some samples, a differential acid neutralisation test was carried out. The objective of this experiment is to dissolve selectively the hydrated phases by adding incremental acid concentrations. By analyzing punctually the equilibrated solutions, the composition of the dissolved phases and their metal content can be estimated. The leaching test results showed that the pH of the leachates remains alkaline during the test period. When the pH decreases under 10 (after 30 days), different behaviours in terms of chemical element release (especially for zinc) were observed. During the test, the oxidation of pyrite seems to slow down, probably due to passivating phenomena. Moreover, the differential acid neutralisation test results allowed a better understanding of the CPB mineralogy and the Zn-bearing cement phases. Zinc and the other metals seem to be fixed within a calcium-magnesium silicate.

May 1, 2007

By J. E. Moyle

The costs of labour and electric power are of prime concern to almost all industrial enterprises, and various methods of reducing their impact on production costs are constantly being developed. Automation is one of these schemes, and has received a good deal of attention in the past few years. In the mining industry, compressed air is almost universally used, and its cost is significant. Although the compressor machinery now in use has achieved a high degree of development, the hazard of explosion and fire still exists in these systems. There is thus considerable resistance in some quarters to suggestions that such installations can be safely and successfully automated. The Milliken power plant consists of two 30,000 lb. /hr. fully equipped high-pressure boilers, four H.P. air compressors, a steam turbine for stand-by power, and several L.P. compressors and vacuum pumps. With the installation of automatic and protective equipment in the machinery section, the shift force has been reduced from three to two men.

Jan 1, 1963

By George Brien, O&apos

The history of the lighting of mine workings dates back to the early part of the 18th century, when small candles known as tallow dips, were used. These were set or held in a lump of wet clay. When looking for gas the flame of. the candle was reduced to a mere glimmer by surrounding the wick below the flame with clay. The candle was then very cautiously raised from the floor toward the roof, the observer screening the brighter portion of the flame with his hand and watching for the first appearance of the pale blue cap above the flame, even at that time, known to indicate the presence of gas. When this appeared the candle was lowered quietly and its flame extinguished before attempting to drive out the gas. A very common and dangerous practice adopted at that time was to get rid of the gas by firing it. This was done by a person selected for his nerve rather than for his caution. Dressed in a? suit of dampened sackcloth or leather, this man well termed a "fireman", would lie prone on the floor of the roadway and light the gas above him by raising his candle fastened to the end of a long stick. If he survived, which was not always the case, he would withdraw promptly to fresh air after the flame had passed over him.

Jan 1, 1924

By Malcolm Black

Introduction Before beginning to write this paper, I decided that I should first find suitable definitions of the words Sample and Sampling. The dictionary gives: "Sample.-A portion indicative of the whole"; and according to Baillie (1), sampling is "That process whereby a representative and comparatively small portion of material is selected from a large bulk, and preserved under such conditions as shall prevent contamination or avoidable alteration, with a view to the formation of valid conclusions regarding the suitability of the bulk for specified purposes". These comprehensive definitions are alike in substance, and indicate that unless a truly representative portion is taken, it is not a sample. Ore 'as mined' generally varies a good deal in composition, and, in crushing, segregation takes place. Some of the minerals present, due to differences in hardness and friability, break into smaller pieces than others, and, on reaching the bin, the coarse particles roll away, leaving the fines behind. The result of this segregation is generally quite noticeable on the conveyor feeding the mill, especially when the bin is nearly empty and the crushing plant shut down. Should the sampling period synchronize with either the coarse or the fines, the sample obviously would not be representative. I agree that this is rather far fetched, but I maintain that such a condition is possible. Assuming that a representative sample may be procured from the feed conveyor, the method of cutting it down for assay has considerable influence in maintaining the original condition of the sample. The finer the material is ground after each cut, the more uniform the sample will remain. To illustrate this point, let us take a quantity of fine sand and add, say, three grains of rice to represent metallic particles. We may mix this sample by any of the known methods, then cut it into four equal portions. It is obvious that at least one of the portions will be without a rice grain. But let us grind the three grains of rice into flour and proceed as before. Now there will be a much greater chance of including some of the rice in each portion.

Jan 1, 1935

By R. O. Loutfy, J. C. Withers

"Titanium powder is produced from a small fraction of sieved sponge, HDH of sponge or gas blown from a melt produced billet. Ore from foreign sources is chlorinated in a very high temperature fluid bed to make TiCl4, then vacuum distilled purified and then reduced to sponge by Kroll processing. Domestic ores of ilmenite or perovskite can be carbothermically reduced to Ti2OC which can be chlorinated at low temperatures of 250–400°C to produce TiCl4 which can be electrolyzed in a fused salt to Ti powder, or the Ti2OC used as an anode in electrolysis to produce Ti powder. The electrolysis process can be operated continuously to produce Ti powder at a lower cost than Kroll processed sponge including produce control size powder. Electrolysis processing was scaled up and operated at the commercial demonstration stage on a continued basis that verifies the potential of a low cost process to produce Ti powder.INTRODUCTIONTitanium and alloys of titanium powder have been elevated to strategic status resulting from a focus of producing meltless titanium components as well as a feed for additive manufacturing processing. However, the high cost of titanium powder has limited wide scale implementation of using titanium powder as a feed to any process to produce titanium components. Titanium powder free of alloying is available as sponge fines from the Kroll process as illustrated in Figure 1. Titanium alloy powder is much more expensive, also illustrated in Figure 1 produced from an alloy ingot or mil product as the feed and then transformed into powder by one of several melt form processes which accounts for the high cost of titanium alloy powder at approximately $60–150/lb. Ton lots of titanium alloy powder (i.e. Ti-6Al-4V) from one source is quoted at $120/lb. in the U.S. It appears that alloy powder production cost by current processing is not sensitive to volume."

Jan 1, 2016

By J. W. Craig

THERE are, broadly speaking, three classes of refractories: acid, basic, and neutral. Fireclay, diaspore, silica, and the sillimanite group of minerals are included in the acid class, which for the most part are not very resistant to basic slags. The neutra! class includes chrome, graphite, and silicon carbide, while most important in the basic class are magnesite and dolomite. Although chrome is a neutral refractory, it has no sharp distinction from magnesitic refractoriness. The two are mineralogically (1) and chemically related, and there is available on the market a complete range of brick from straight chrome to straight magnesite. In many indus trial applications, one. type may be replaced by another. The present paper is confined entirely to such refractories. The following types of basic and neutra! brick, each sold under sorne special trade name, are available for use in Canada: (1) Burned chrome from crude ores (2) Burned chrome from treated ores (3) Chemically bonded (unburned) chrome-magnesite ( 4) Burned chrome-magnesite (5) Chemically bonded ( unburned) magnesite-chrome (6) Chemically bonded (unburned) high-iron magnesite (7) Burned high-iron magnesite (Regular) (8) Burned low-iron magnesite (9) Burned olivine-magnesite (10) Burned magnesitic dolomite-chrome (Magnecon) (11) Chemically bonded magnesitic dolomite-chrome (Magmecom) (12) Dolomitic brick

Jan 1, 1936

By Javier Linares García

At then end of this year will be 10 years of producing concentrate for Antamina. This is a summary of what occurred over the last decade to increase production and tonnage above the design tonnage of 70,000 tonnes per day, up to an average of 100,018 tonnes per day in 2010, an increase in production of 42.9%. Equipment currently in use is the originally installed equipment, signifying a meaningful increase in capacity without capital. In this paper, the different phases of improvements and the realization of their impacts in chronological order will be outlined. Figure 1 below shows the average daily tonnage processed each year (tonnage throughput each year/calendar days), as well as the percentage increase over the tonnage of design.

Jan 1, 2012

By J. M. Cummings

DURING the past year, the writer has investigated the treatment of a variety of British Columbia tungsten-bearing ores. Much of the test-work described in this paper was carried out in collaboration with Mr. A. G. Lyle in association with the British Columbia War Metals Research Board at the University of British Columbia. The remainder was completed in the laboratories of the Department of Mines at Victoria. Two mills in the Province are at present treating tungsten ores. Descriptions of these are included through the co-operation of Messrs. S. Gray (1) and A. A. Almstrom (2). MINERALOGY, OCCURRENCE, AND SPECIFICATIONS In the present paper, attention is directed solely to scheclite, inasmuch as known occurrences of other tungstcn minerals in British Columbia are of mineralogical interest only. The properties of scheclite are listed below: Percent W03 .. 80.6 Tenacity ...... Very brittle Çrystallization Tetragonal Lustre ........ Vitreous to resinous Cleavage ...... Good in 4 directions Magnetism ... Non-magnetic Specifie gravity 6.05 Diaphaneity .. Transparent to translucent Hardness. . . . . . 4.5-5.0 Scheelite may contain as much as ten per cent of molybdenum in solid solution, but most of the specimens from British Columbia examined by the writer were relatively pure.

Jan 1, 1943

By C. Joulian, A. G. Guézennec, A. Chmielarz, Y. Ménard, M. Hanke, P. d’Hugues

"The copper concentrate used in this study is produced by flotation of a black shale organic rich ore. This resource is a carbonate-rich, polymineral concentrate. In the last 5-6 years, ore characteristics changed and the concentrate grades degraded. This study evaluated bioleaching of the concentrate in stirred tank reactors as an alternative to the pyrometallurgical technology that is currently applied, and which may no longer be feasible in future given the concentrate chemistry.The first part of the study focused on testing non-traditional operating conditions during continuous bioleaching experiments: high solids concentration (> 20% solids), reduced agitation and aeration rates. For the same residence time, bioleaching performance at high solids loading (25%) was the same as that reached during previous bioleaching experiments at 15% solids. No mixing or microbial issues were encountered. The bacterial consortium used in the experiments demonstrated a high copper tolerance.The second part of the study was devoted to technology development for metal recovery from copper bearing solutions obtained during bioleaching experiments. Due to the high copper concentration of the leachate, solvent extraction prior to electrowinning was not necessary. After iron removal, high quality copper cathodes (morphology and composition) were obtained from the PLS by electrowinning."

Jan 1, 2014

By I. C. Brown

Introduction Many tables of nomenclature for igneous rocks have been introduced from time to time, and each has its strong proponents. As a result, any discussion of igneous? rocks is apt to prove confusing unless the names used for these rocks are defined. This ?became so obvious to a discussion group, formed by the members of the Geological Survey of Canada in 1948, that an attempt was made to establish a scheme of nomenclature that could be used by any member mapping anywhere in Canada. The writer was asked to co-ordinate the ideas presented by individuals in the discussion group, to arrange them in tabular form, and, later, to distribute copies of the resultant table to Canadian universities, provincial geological surveys, and some other geological discussion groups. Many useful suggestions and criticisms were received, were studied ?by members? of the original group, and, so far as practicable, were incorporated in the scheme of nomenclature. The result is the table presented here. This nomenclature of igneous rocks is at present being used by most members of the Geological Survey of Canada who are working with igneous rocks, and by some Canadian universities. We hope it will be found useful and be more widely accepted. With this idea in mind, certain principles were adopted in drawing up the nomenclature.

Jan 1, 1952

By D. W. Li

Due to the ultrasonic testing and mechanical wind speed sensor have high requirement for the environmental of the coal mine, the charge induction wind speed detection method based on wavelet analysis is proposed. The same wavelet disturbance detection method is used at a fixed distance to obtain an induction signal to obtain a pass time, and then calculate the magnitude and speed of the wind. Simulation and verification experiments show that the method has application across a wide range of test speeds (up to 60 m/s). The metal probe causes little pipeline flow field interference. The method is particularly well-suited to dusty environment, and does not cause dust deposition through long-term operation. It can be widely used in coal mines for point wind speed continuous online testing.

Aug 1, 2013

By J. E. Udd

A core sample for this study was taken from the sulphide ore of the Geco Mine. The subsequent research was based on the assumption that a part of the scattering of strength-grade data could be correlated with variations in the chemical and/or mineralogical compositions of the samples. The results demonstrate clear relationships between strengths in tension and compression and the zinc-iron contents of the rocks.

Jan 1, 1977

By J. J. Denny

IN a preliminary paper (1) it was shown that the addition of small quantities of metallic aluminium powder almost completely inhibited the solubility of siliceous material in the beaker. Six rabbits exposed to quartz dust for six months all showed well developed silicosis. Seven rabbits exposed to quartz dust plus 1 per cent metallic aluminium powder for the same period did not develop silicosis. At that time, we were not in a position to state either the manner in which metallic aluminium reduced the solubility of siliceous material, or, from the animal experiments, whether the aluminium was acting locally or systemically, or for what period after the cessation of dusting it would continue to act. This paper reports the further progress of this investigation. CHEMICAL EXPERIMENTATION The technical details pertaining to the various substances used in the experiments are given in an appendix which is on deposit with the American Documentation Institute, Washington, D.C. For lack of space, it is not printed here. The term 'solubility' is used to indicate the concentration of silica in the solution under the conditions as noted, determined colorimetrically (2), and expressed as parts per million (p.p.m.). The term 'reduction in solubility' indicates the difference between the solubility of the .silica in the presence of the aluminium powder and its solubility in the absence of aluminium powder. It will be noted that the solubility figures for different samples of quartz with no added aluminium vary considerably. The figures do not refer to an equilibrium solubility of silica but to the actual amount of silica dissolved from a given sample in a given time at a given temperature. In view of the fact that quartz dissolves extremely slowly, it is evident that the actual figures in any case will depend upon the surface exposed, i.e., fineness of grinding of the different samples.

Jan 1, 1939

By A. M. Abdel-Rehim

The present work reports a study of production of thorium concentrate from Egyptian monazite by decomposition of ammonium carbonate solutions containing ammonium thorium and uranyl carbonate complexes. These solutions were obtained from the processing of monazite by alkaline leaching in ball-mill autoclaves, followed by selective separation of thorium and uranium from lanthanides by autoclave leaching of the hydroxide cake obtained with ammonium carbonate - bicarbonate solutions. The separation of thorium and uranium in the form of thorium concentrate from their carbonate complexes was achieved by different methods, including neutralization of solutions at pH = 6.7 by acid, addition of alkali at pH = 11.5, heating of solution at 100°C and processing of carbonate solution with steam under pressure in steel autoclaves. Processing of solutions of thorium and uranyl carbonate complexes in an autoclave with steam causes their decomposition. Complete recovery of thorium 99.8% and 98.4% uranium recovery in thorium concentrate was attained at 120°C and steam pressure 2 atm, within 10 min. Meanwhile, the recovery of lanthanides was low and did not exceed 1.1%. The thorium concentrate produced contains 67.82% Th, 4.6% U and 3.14% REE. All methods achieve complete separation of thorium and uranium from their carbonate solutions, but the first two methods are unfavourable for the industry due to the high cost of reagents and their inability to regenerate the ammonium carbonate. The decomposition of ammonium thorium and uranyl carbonate complexes with steam under pressure is recommended for industrial application for its simplicity and the ability to regenerate the ammonium carbonate.

Jan 1, 2004

By K. Kryst, K. Elkayar

The increasing need to process lower grade contaminated copper concentrates and simultaneously produce higher purity copper cathodes necessitates a more diligent control in the electrorefining process. Ion exchange processes can be a powerful tool in controlling electrolyte impurities to ensure trouble free operation within the tankhouse and to help maintain cathode purity. In addition, some impurities can be recovered as a value added product. The use of a short bed ion exchange process provides a unique opportunity for impurity management in copper refineries. Several metals are discussed in this paper, including Sb, Bi, As and Ni and their methods of control and recovery within the copper electrolyte circuit. INTRODUCTION To produce a high purity copper product by electro-refining a copper electrolyte, it is important to control the concentration of impurities such as arsenic (As), bismuth (Bi), antimony (Sb), and nickel (Ni). These impurities are introduced into the electrolyte from the copper anode and can affect the copper product and the production operation. The presence of As in the copper product results in a lower electric conductivity and reduced workability of the copper. High levels of Bi in the electrolyte will result in a copper cathode product containing Bi. High Sb concentration will cause undesired floating slimes. A variety of methods have been developed to control the level of these impurities in the copper electrolyte including precipitation, liquid extraction, and ion exchange. These impurities can be recovered and used. This paper discusses novel methods that utilize short bed ion exchange technology to control these impurities. Also, the use of ion exchange to recover acid from the liberator cells bleed for reuse in the tankhouse is reviewed. SHORT BED ION EXCHANGE Short bed ion exchange technology has been employed extensively in the metal finishing industries for over forty years. Unlike conventional ion exchange, short beds are fixed beds without freeboard space. The application of short bed technology results in significant benefits when compared to conventional ion exchange. The resin used in this technology has a significantly smaller diameter than conventional ion exchange resin. As a result of the smaller resin size, exchange kinetics improves dramatically. This facilitates operation at higher flow rates and the use of smaller beds with a small mass transfer zone length. Smaller beds are especially important for applications that use chelating resins due to the high cost of the resin.

Jan 1, 2019