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By Peter N. Blakey, Jean-Paul Paquette, Barton A. Thomson

"FROM THE BEGINNING OF THE PIT, it was known that the surface mining method had a projected life of about ten years, and that the ore extended to depths recoverable only by underground mining. When serious consideration was given to underground mining in 1968, it was realized that tremendous advantages could be gained by starting the underground mine as early as• poss1ble. These included: 1. The availability of underground ore for grade control, which would become more difficult as the pit deepened. 2. The need to develop new systems, equipment and skills to take full advantage of the technological revolution in underground mining. 3. Early knowledge of rock behaviour through trial mining on a small scale prior to finalizing plans for major blocks. In addition, the pit would be available to guarantee the mill supply if problems were encountered. 4. With sufficient time and early mining experience a much better job could be done on all mine planning. Because ample reserves of economic underground ore were virtually assured, the desired underground mining capability became a function of two restraints: first, the time required to excavate and construct the permanent headframe, shaft and ore-handling facilities necessary to handle large volumes of stope ore; second, the time for lateral and stope development on at least one level which would normally follow shaft sinking. The decision made was to move immediately on the permanent hoisting installations and at the same time embark on the planned ramp from surface, which would allow much stope preparation to be completed prior to .bringing the shaft on stream. Both projects were placed on an urgent basis early in 196S' and the following decisions made shortly thereafter."

Jan 1, 1974

By Dan Zou, Ji Chen, Deqian Li

"Bayan Obo mixed RE concentrate is the largest RE source in the world. RE elements occur dominantly in bastnaesite and monazite. This paper describes a clean and green technique for processing Bayan Obo mixed rare earth (RE) concentrate. A two-step oxidation method can lead to the effective recovery of REs, thorium (Th), fluorine (F) and phosphorus (P). Ce has a property of valency change, enabling the separation of it from other RE(III) elements. Making use of the interactions of cerium (IV) (Ce(IV)), F and P, a new extraction system was created to separate Ce(IV) effectively from other RE(III) while recovering F, P and Th by complexing F and P following the oxidation of Ce(III) to Ce(IV). The method includes two parts. Firstly, bastnaesite is oxidized by air roasting and sulfuric acid leaching. And then a first leach liquor containing Ce(IV), F and P is obtained. Secondly, monazite was converted into REhydroxide through alkaline attack and then Ce(III) in the RE-hydroxide was oxidized into Ce(IV) by wetair oxidation. After sulfuric acid leaching the oxidized RE-hydroxide, a second leach liquor is obtained. The two parts of leach liquor containing Ce(IV), F and P are then extracted by Cyanex923 to obtain CeO2, CeF3 and CePO4 based on the complex of Ce(IV) with F and P. The raffinate was further extracted by the primary amine N1923, and Th-product was recovered as ThO2. The RE elements recovery yield during the whole process is greater than 92%. The new technique not only provides a new way for Bayan Obo RE ore utilization, but also avoids resource waste and environment pollution.INTRODUCTIONRare Earths (REs) refer to lanthanides, including scandium and yttrium. Owing to the similar structure and property of RE(III), it is difficult to separate them from each other, especially for the adjacent elements. According to the United States Geological Survey, in 2010, the whole world has about 142 million tonnes of rare earth reserves. In that, China ranks the second with 22% following Brazil which ranks first with 32% (Cheng, 2011). There are three main RE ore types in China with about 80% mixed ores in Bayan Obo, 10% bastnaesite ores in SiChuan and ShanDong province and 2.9% ion adsorption ores in Southern China. Bayan Obo mixed RE concentrate consists of bastnaesite and monazite. The concentrate contains CeO2/_REO of 50% and there are 7–8% F, 4-6% P and 0.2–0.3% Th."

Jan 1, 2016

By R M. Ennis, J. C. Botham

This paper is one of a series pre-pared to study the role of fuels and reductants in metallurgical processes, especially from the viewpoint of Canadian requirements. The object of these studies is to provide a reason-ably authoritative interpretation on the interrelation of fuels in light of the considerable changes that have taken place in the Canadian energy field during the past few years. Previous papers in this group have dealt with the problem generally, and specifically in terms of the development of the iron and steel industry of Western Canada. These latter papers, presented at the Symposium on Iron and Steel in Western Canada held in Edmonton, Alberta, on September 8-9, 1959, surveyed the ferrous processes of interest for use in Wes tern Canada, especially with regard to solid fuel requirements. At that time it was evident that there was a need for a similar study of the fuels aspect of the non-ferrous metals industry.

Jan 1, 1961

By Claude Bourgoin

"The Copra massive sulphide deposit occurs as a continuous slab of ore dipping at approximately 40 degrees within a sericite schist formation. The orebody has been delineated over a distance of more than 5,000 feet down dip. This paper is mainly concerned with the mining procedure, and particular reference will be made to the use of steel mill holes and hydraulic roof supports. The gravel backfill line, which is operated both by gravity and hydraulically, is described. The paper mentions some of the operational problems, discusses the feasibility of longwall mining and presents the information obtained from stope testing."

Jan 1, 1966

By J. C. Marchand, M. A. Berube

"L'objectif principal recherché lors du broyage d 'un minerai est de libérer adéquatement ses valeurs utiles en vue de leur concentration ultérieure. La pratique courante consiste à tenter d'obtenir un produit de broyage d'une granulométrie constante. Malheureusement, les propriétés texturales des minéraux utiles varient naturellement dans un gisement et une telle stratégie n'entraine pas toujours pour ces minéraux un degré de libération constant. Pour un rendement optimal du procédé de concentration, cette variable très importante doit donc être périodiquement vérifiée.Jusqu'à maintenant, la plupart des études de libération des minerais se font en examinant des sections polies de particules du minerai broyé. Le GRAAIM a récemment assemblé un système modulaire d'analyse d'images qui servira en grande partie à des mesures automatiques du degré de libération des minéraux. Le système s'avère relativement peu coûteux comparativement à la plupart des analyseurs de texture conventionnels si l'on considère que plusieurs de ses composantes, par exemple le miniordinateur, sont utilisées à une foule d'autres applications, et il permet de plus une grande souplesse d'utilisation puisque l'on a qu'à construire des algorithmes de mesure et de calcul en fonction de l'objectif recherché. Des programmes particuliers permettant des études automatiques de libération sur des sections polies de particules ont ainsi été élaborés. Ils permettent également des mesures de teneurs et de distributions granulométriques apparentes des particules. Des résultats obtenus dans le cas de minerais de fer sont brièvement présentés afin d'illustrer la technique."

Jan 1, 1983

By E. M. De Souza, R. Penner

"Water is encountered at the majority of underground mines, both over their lifetime and during each stage of development and production. The dewatering system is one of the most important and costly components of an underground mining operation and it is often not well designed and analyzed. An effective design of a mine dewatering system will greatly reduce its energy cost as well as improve working conditions and reduce production costs. A computer-based system, called Qpump, has been developed to assist the underground operator to effectively design and/or assess over-all and local mine dewatering systems. The design features and principles used in the development of Qpump are introduced and an example which illustrates typical applications is presented.IntroductionTraditionally, dewatering operations have been given lower priority than many other operations in underground mining. Invariably water will be encountered during the sinking of the mine shaft, during development and subsequent production. The dewatering system thus becomes a very important component of an underground mine operation and, in fact, any mine manager will attest to the importance and necessity of an efficient mine dewatering system.The water problem is of varying importance at different mines. There are several factors that contribute to the water encountered. It is a function of the mining method and techniques utilized (backfill system, drilling and raising technology, dust control sprays, shaft water rings, etc.) and of prevailing conditions (ground water, rock structure and permeability). In some cases a mine may be so dry that little pumping is required while in others, the weight of water pumped may exceed by many times that of ore mined.The successful design and application of a mine dewatering system is dependent upon the operating conditions of each specific operation. There are no standard procedures and systems which can be used for all mining situations. However, an effective water system will greatly reduce the energy and production costs of a mine, improve working conditions and eliminate headaches because of flooded working places."

Jan 1, 1993

By J. L. Wilson

"Many modern concentrators with VSD driven SAG mills still rely on the control room operator to manually adjust the speed in reaction to increasing bearing pressure. All too often, the problem with this strategy is by the time the operator reacts with a sudden speed increase, the SAG Mill is likely already on its way to loading up. To assist the new operators, the SAG Mill at B2Gold’s Fekola Mine in Mali needed a robust control that could handle load changes and unmeasured disturbances with minimal operator intervention. With modern Distributed Control Systems (DCS) powerful enough to run advanced control, they often have Model Predictive Control (MPC) blocks built in or available as an “add-on” license, and thus MPC can be readily implemented within the modern concentrator with a relatively low added capital cost. This paper discusses an implementation of two single output MPC controllers to control the SAG Mill at Fekola. This was implemented using the existing signals and advanced control blocks available to the installed DCS.INTRODUCTION Many modern concentrators with VSD driven SAG mills still rely on the control room operator to manually adjust the speed in reaction to increasing bearing pressure. All too often, the problem with this strategy is that by the time the operator reacts with a sudden speed increase, the SAG Mill is likely already on its way to loading up. The next step the operator may take may be to cut back the feed rate, or production until the SAG is once again stable. With this sudden reaction comes an abrupt change in SAG rotational speed and power consumption that sends a surge of material down the circuit as the mill suddenly ejects more pulp. Furthermore, choosing a higher rotational speed can lead to higher than normal liner wear as the cataract overshoots the toe of the charge and impacts the liners. After start-up at B2Gold’s Fekola Gold Mine in 2017, the SAG mill was being controlled manually. The SAG rotational speed was adjusted manually by the operator in step changes depending on whether the SAG bearing pressure was increasing, decreasing or stable. During this time of manual control, the SAG fresh feed rate was also adjusted to a tonnage setpoint with a PID controller. Generally, the SAG fresh feed rate setpoint was kept at a target value, but then the feed rate was throttled back if the SAG mill or grinding circuit showed signs of overloading. The extra challenges were that the operators had limited experience and were concurrently learning how the plant operated. Also, they were also occupied with managing situations in the rest of the plant. Often their attention was drawn away from the SAG mill and during that time, the SAG Mill would load up before they could react."

Jan 1, 2019

By L. Tong

"The oxidation of Quebracho was evaluated by acid-butanol assay, which indicates depolymerization of Quebracho. Anthocyanidin, an oxidation product of Quebracho, is stable at 95?C for up to 2 h. The ionization, complexation, and oxidation properties of Quebracho were discussed. Complexation of metal-Quebracho occurs at ambient temperature. The formation of complex precipitates is influenced by the acidity of the solution. Temperature is another important parameter that influences the oxidation and the complexation of Quebracho. Quebracho-ferric complex precipitate forms at 90?C, 0.1 mol/L H2SO4. The formation of Quebracho-metal complex in the leach solution is a possible reason for the consumption of Quebracho. Quebracho molecules adsorption on the mineral surface is reduced by consumption of Quebracho, resulting in poor sulfur dispersing effect in the leaching process. INTRODUCTIONQuebracho is used as a sulfur dispersing agent (SDA) in the pressure leaching of zinc concentrate as stated in U.S. Patent No. 3,867,268 (1975). It prevents the zinc sulfide particles from being coated with molten sulfur, thus preventing the inhibition of the zinc leaching reaction. Recently, the sulfur dispersing effect of Quebracho was investigated in the oxygen pressure leaching of nickel concentrate. The oxygen pressure leaching of pentlandite can be represented by reactions 1-3."

Jan 1, 2012

By A. R. MacPherson

"This paper considers four aspects of autogenous grinding. Part 1 discusses statements on power efficiency of autogenous grinding compared to conventional crushing and grinding systems. It also demonstrates how high-power efficiency can be obtained from autogenous grinding systems. Part 2 considers a simple method of testing ores to determine the type of autogenous plant which can treat these ores on a commercial basis. A comparison of testing for simple small plants vs large plants or complex ores is included. Part 3 considers important aspects which have to be considered in proper design of an autogenous grinding system. Part 4 discusses problem ores and how they can be treated in an autogenous system. INTRODUCTIONAfter about 35 years of using autogenous grinding plants in the mining industry, it is perhaps time to review where we are with this, by now, relatively old development. Autogenous grinding in this paper means grinding run-of-mine ore by fully autogenous means or by using a ball charge to assist the grinding (semi-autogenous). Also, autogenous grinding can be eitherby dry or wet.The use of autogenous grinding in the fifties was making its slow start, and it was not until the sixties that more of the mining industry would consider its use . By the seventies, most builders of new plants would have considered autogenous grinding, whether they used it or not, in the final design.In the eighties, most large plants use autogenous mills and to reduce over-all operating costs, many older conventional plants are now looking and actually retrofitting these old plants with autogenous grinding mills.It is evident that many misconceptions concerning autogenous grinding are still current. Some come from improperly designed plants which result from poor test work. There are many considerations in the proper design of autogenous plants. Some ores have been found to give problems even in a well designed plant. These ore types are beginning to be classified and recognition in the test stage allows steps to be taken in the design so that these ores can be efficiently handled in autogenous grinding plants.Therefore, this paper will address the following aspects of autogenous grinding:1. Misconceptions regarding autogenous grinding.2. Testing of ores to ensure a well designed commercial plant.3. Important considerations in mill design.4. Difficult ores, their recognition and types of design to handle such ores."

Jan 1, 1989

By R. W. Boyle

"The concept of using chemical methods in prospecting dates back at least to the middle of the 16th century. Modern methods of geochemical prospecting, however, based on secondary haloes and utilizing trace-element techniques, were first practised in the U.S.S.R. and the Scandinavian countries in the 1930's. After 1945, methods based on soils, stream sediments and vegetation were rapidly developed in the U.S.A., the United Kingdom, Canada, France and other countries.The modern methods of geochemical prospecting owe their rapid development in the 20th century to the following:1.-Recognition of the primary and secondary dispersion haloes and trains that are associated with all mineral deposits. 2.-Development of accurate and rapid analytical methods utilizing the spectrograph and the various specific sensitive colorimetrie reagents, especially dithizone. 3.-Development of polyethylene laboratory ware of all types and the development of resins. This permitted greater freedom of field analyses and reduced the incidence of contamination.4.-Development of gas chromatography. This permitted the rapid and accurate determination of hydrocarbons in petroleum prospecting.Future research in geochemical prospecting should be focused on the following tasks: 1.-Definition of geochemical provinces and their relation to mineral deposits. 2.-Development of methods for discovering large low-grade deposits. 3.-Development of methods for discovering deeply buried deposits. 4.-Further development of methods to outline primary haloes. 5.-Eiucidation and formulation of techniques to relate the size and intensity of anomalies to the grade of the deposits. 6.-Development and refinement of biogeochemical methods, especially those based on indicator plants, chlorotic or toxic effects, and microbiological techniques. 7.-Definition of the types of primary and secondary haloes associated with accumulations of oil and gas."

Jan 1, 1967

By Michel Ruel

Most plants do not track how their systems perform. Optimization is the easiest way to benefit from your control systems. We suggest an approach in four phases. The first phase is to assess all equipment to determine the performances for instruments, valves, variable speed drives, and other equipment. The second phase is to remediate instrumentation problems, including the ones pertaining to valves, variable speed drives, analyzers, transmitters. When equipment is in order, loops are put back in automatic mode. If a loop oscillates, use standard default values for this type of loop. The third phase consists in validating the control strategies, properly configuring the systems (control system, programs and parameters, HMI, alarms), and then tuning the loops and control strategies. The fourth phase consists in analyzing the process and expected performances in order to optimize the control loops and control strategies. If performance is not sufficient, a decision tree will be presented to determine the right approach: advanced regulatory control, model predictive control, or fuzzy logic control. Once all steps have been completed, control performance monitoring software is used to sustain the results and pinpoint equipment or loops not performing as stated. Alarm management and rationalization could also be performed after auditing the alarm system, if needed. Examples from plants will be used to demonstrate how this step-by-step method is applied and produces results. INTRODUCTION Maximizing what you already have is the best investment to remain competitive. This article aims to show the benefits of a systematic approach using modern tools to improve plant performance. We at BBA suggest dividing the work in four phases, and a subsequent phase can begin when the previous one has progressed: Assess, Remediate, Stabilize, Optimize, or add advanced control. This approach has been successfully applied to several sites. Examples and illustrations from these plants demonstrate how this step-by-step method is applied and produces results. Under the BBA method, there are four questions to answer before proceeding to the next step. For each control strategy, you should ask the following questions: Assessment: Does it work? Remediation: Do you use it? Stabilization: Is it stable? Optimization: Does it perform? Do you need advanced control?

Jan 1, 2019

By J. De Geoffroy, T. K. Wignall

The paper describes a statistical method based on regression and classification analysis which is designed to assist exploration management in the selection of prospecting areas and drilling targets in regional programs. The classification is based on three criteria which are formulated from sets of relevant geological, geophysical and geochemical factors: (a) regression estimates of expected ore values, (b) Bayesian probabilities of success and (c) expected utility payoffs. The advantages of the method are: (a) rational and unbiased ratings for areas or targets in a manner consistent with management's goals; (b) calculation of probabilities of success and confidence intervals for the ratings, and (c) rapid and accurate handling of a large amount of data by computer programs.

Jan 1, 1970

By F. D. Aaring

"IntroductionTHE PINCHER CREEK gas condensate field, in Township 3, Range 28, and Townships 3 and 4, Range 29, West of the Fourth Meridian, was discovered in 1947 by the Canadian Gulf Oil Company with the completion of Pincher Creek No. 1 well in the Madison lime-stone of Mississippian age.This discovery was the result of a great deal of detailed seismic work in the area and is a credit to the geophysical personnel of the Company. The depth of the reservoir varies from 7,400 feet to 8,200 feet subsea, with the established water level at -8,200 feet. The predicted depth was but a scant 100 feet from that found in the discovery well, at 11, 705 feet. Since the discovery of the reservoir, three additional wells have penetrated the Madison limestone and have further verified the original •seismic interpretation of the limits of this reservoir.To date, •only a very small amount of gas has been produced from this field. Consequently, the reservoir studies that have been made so far are predominantly based on investigations of the phase behaviour of the fluid and physical characteristics of the reservoir rock. In view of the above limitations, it has been necessary to set up and perform model reservoir studies with the fluids and to recover as much core from the productive Madison limestone as possible in order that it might be analysed by conventional laboratory technique and be subjected to detailed microscopic geological examination."

Jan 1, 1952

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

THE Michipicoten area, one of numerous iron-bearing "Archean" segments in the Shield, contains two main types of iron formation, a normal Keewatin-type, consisting of interbanded chert, siliceous magnetite and jasper, and, gradational to this, a carbonate-sulphide type which contains large de-posits of siderite and pyrite. The carbonate-sulphide type of iron formation bears a direct and intimate relationship to the volcanic development of the area; it there-by affords some insight into genetic problems of Archeanron formation in general. The purpose of this pa-per is to summarize the geological setting of Michipicoten iron formations and to briefly review genetic aspects of recent work in the area. GENERAL GEOLOGY in largely by assorted volcanics and sediments of the Michipicoten series and younger, regional granite masses. (Fig. 1). The Michipicoten series comprises a thick assemblage of mixed flows and pyroclastics together with elastic sediments and banded iron formations. The volcanics belong to the Andesite-Rhyolite Association, and characters-

Jan 1, 1961

By J. T. Fyles, C. G. Hewlett

"THE REEVES MACDONALD mine is in the Sa Imo-Pend d'Oreille mining area of southeastern British Columbia. It is on the Nelway-Waneta road 4 miles west of the border-crossing point of Nelway. The Reeves orebody from which all production has come is one of several mineralized zones in easterly-striking limestones occurring between the Pend d'Oreille and the lower part of Salmo River.The property was originally located as two groups of claims by R. M, Reeves and J. H. McDonald. The two groups were consolidated in 1925. and extensive development work was done from then until 1930 and again in 1937, but no ore was shipped. The mine was reopened in 1947 and, between 1949 and 1953, 1,057,804 tons of ore was mined. Concentrates recovered contained 85,626 ounces of silver, 19,394,092 pounds of lead, 72,076,495 pounds of zinc, and 455,051 pounds of cadmium. Low metal prices forced the mine to close in 1953, but operations were resumed in November, 1955.The orebodies at the Reeves MacDonald mine are steeply plunging lead and zinc sulphide replacement deposits in a banded limestone named the Reeves limestone. The orebodies contain pyrite, honey-coloured sphalerite, and galena, and are surrounded by a dolomitized zone. In the Reeves orebody, where the relationships are known, the dolomite has the same general shape as the orebody. Four zones of sulphides are known on the property (see Figure 1). Three of these, the Reeves, B. L., and O'Donnell, are believed to be faulted segments of one mineralized zone. The fourth, the Point ore zone, exposed on the north bank of the Pend d'Oreille River, is not developed and its structural position is not known, but it appears to be a separate deposit."

Jan 1, 1949

By M. Sengupta

International trade in minerals plays a very important role in the economic growth of many nations. Several less developed countries a1•e heavily dependent on their mineral exports for earning foreign exchange, which is needed for industrialization. Mineral exporting nations experience many problems in international mineral markets; the most important are tariff barriers, deteriorating terms of trade, instability in metal prices, etc. The formation of international mineral cartels to raise prices can be successful only to a limited extent and only for a short period of time.

Jan 1, 1976

By L. M. Dwarkin

Introduction Avital factor in the success of any coal mining operation is the method of roof support employed. A coal seam in? place has been described as the filling in a geological sandwich and the process of mining as the art of snatching the filling from the midst of the sandwich. The difficulty of this task can be appreciated -in the realization of the tremendous weight bearing on a coal seam due to overlying strata; a weight that can exert pressures of several thousand pounds per square inch. Over the years that mining has been carried on, methods have been evolved by arduous trial and error, making possible the successful extraction of billions of tons of coal. However, these time-proven methods are not enough. The constant demand for faster and cheaper production, the necessity of mining under increasingly difficult conditions, and the requirement for higher standards of safety, call for ever better and more efficient roof support. A recent and very promising development in answer to this need is that of Roof Bolting. Roof Support in General Before proceeding to the subject proper, a brief discussion of the older roof support methods is of value in illuminating the difficulties involved and the problems to be solved.

Jan 1, 1951

By M. M. Williams

ALBERTA has been generously endowed with oil, natural gas, coal and water power, thus giving power producers a wide choice in the type of plant and fuel which can be used. Therefore, with such a variety of energy sources to choose from, why was coal selected as the primary fuel at Calgary Power's Wabamun steam plant? This part of the paper will cover the circumstances that led the Company to decide in favour of coal. The second part, to be presented by C. F. Doerr, will describe how the Wabamun coal mine has been developed to supply the large fuel requirements of the power plant. Before considering the Wabamun plant, we require a general under-standing of? the Company's electric system and load. Power is fed into a 5,100-mile high-voltage transmission grid from eleven hydroelectric plants and from the Wabamun steam electric plant. These plants have a combined generating capacity of 820,000 horse-power. Of this total, the hydro

Jan 1, 1963

By A. S. Romaniuk

More than a decade ago, CANMET management recognized the need to make better use of existing technological information in mining and extractive metallurgy-two fields basic to the economic well-being of Canada. There were at that time no indexes or files dedicated to disseminating technical information for the many minerals mined and processed in Canada, including coal. CANMET, with the nation's largest research and library resources in the minerals field, was in a unique position to fill this need. Initial efforts were concentrated on building a mining file, beginning with identification of world sources of published information, development of a special thesaurus of terms for language control and adoption of a manual indexing/retrieval system. By early 1973, this file held 8,300 references, with source, abstract and keywords given for each reference. In mid-1973, operations were computerized. Software for indexing and retrieval by batch mode was written by CANMET staff to utilize the hardware facilities of EMR's Computer Science Centre. The resulting MINTEC file-one of the few files of technological information produced in Canada-is the basis for the national literature search service in mining offered by CANMET. Attention is now focussed on building a sister-file in extractive metallurgy using the system already developed. Published information sources have been identified and a thesaurus of terms is being compiled and tested. The software developed for CANMET's file-building operations has several features, including the selective dissemination of information and production from magnetic tape of photo ready copy for publication, as in a bi-monthly abstracts journal.

Jan 1, 1979