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By Daniel Hodouin, Bruno Girard, Claude Bazin

"Mineral processing and smelting operations have the reputation of being complex processes. Process operators of these unit operations have acquired from experience and basic training a superficial understanding of the relationships between process output and manipulated variables. This understanding, which is a very valuable know-how for process control and optimization as well as for operator training, is however difficult to extract. This paper describes a time series based approach that can be used to extract this know-how, which can subsequently be used for operator training. The method is illustrated with an example taken from a smelting process.IntroductionThe emergence of Total Quality Management and Statistical Process Control philosophies in the North American industry (Brown, 1991 ), as well as the increasing popularity of the IS0- 900x standard accreditation, provide a strong incentive to review the training procedures for plant operators. The importance of employees training is acknowledged in two of the 14 points of Deming's road to quality (Deming, 1982) as well as by control engineering consultants (Hendricks et al., 1994). However guidelines for the operation of industrial processes are often transferred from an operator to another one with allowance for flexible interpretation of many operating rules. Such transfer is typical of complex industrial processes to which particulate processes of ore dressing and extractive metallurgy belong.Capturing the knowledge of experienced operators is often a difficult task. Cognition engineers are able to extract this knowledge and transfer it into rules that ultimately are implemented into expert systems. Cognition engineers are however not always available and plant supervisors may prefer to keep training as an internal liability. Another difficulty through interviewing of the process operator is its lack of willingness to transfer what he has learned by hard working to other people, whose ultimate goals are to develop computerized applications that may replace him in a near future, or reduce its importance in the production line.This paper shows that time series can be advantageously used to capture the average process understanding of plant operators and to help reviewing training procedures. The method s illustrated with data collected during normal operation of electric arc furnaces and it is shown how the approach has led to a fruitful discussion between process engineers and operators that ultimately provided savings of more that $200,000 per year per furnace. There are 9 furnaces in the studied foundry. Such savings are not the results of application of advanced control strategies nor of ""miracle press button software», but of an improve awareness by engineers and operators of the importance of properly defining the operating procedures to control a process."

Jan 1, 1996

By Eugene Larochelle

The serpentine of the Eastern Townships of Quebec is more or less seamed and impregnated with chrysotile asbestos, of which we note two types: the cross-fibre and the disseminated fibre. The cross-fibre type always appears in fibres or crystals arranged parallel to one another, and disposed at right angles to the walls of the matrix serpentine. The length of fibre of these veins, which run in every conceivable direction, even crossing ?one another, varies from microscopie dimensions to three and sometimes four and even five inches. It is the principal form of asbestos found in the serpentine of Thetford Mines, Black Lake, Coleraine, and Asbestos. The disseminated-fibre type, which is the main product of the serpentine of Broughton township, in which ate located the mines at East Broughton, does not form veins, but occurs in the serpentine without any definite arrangement. There is a difference in the toughness and hardness of the rock of the two types, the Broughton serpentine being softer than that at Thetford. The disseminated-fibre section of the serpentine belt is probably more regular in its content than is the cross-fibre section. Nevertheless, it contains no 'crude,' which is the most valuable of asbestos, and the fibre is usually shorter than the cross-fibre average.

Jan 1, 1928

By W. Leblanc, J. Phalen

This paper tells the story of a serious mine fire on a mechanized longwall face in a submarine coal mine at Glace Bay, Nova Scotia. The story gives, in chronological order, a technical account of the steps taken to investigate, fight and contain the fire. The time during which the events took place spans from June 19 to November 7, 1975.

Jan 1, 1976

By C. A. Y. Shephard, H. L. Brusset

Pressure maintenance by water flooding in the Pembina Field made consideration of wet crude dehydration and disposal of the produced water mandatory. Crude dehydration, the treatment and disposal of produced water, as well as the sale of gas and crude oil were expected to be handled more efficiently at one central point than at several conventional batteries. This plan was effected by routing the produced fluids to the central station by way of several well testing batteries referred to as satellites. To realize the full efficiency inherent in such consolidation the entire system was made self-regulating. Programming ensures the testing and proper routing of all products to their destination. Forty producing wells have been self-operated during the winter 1959 -1960 with gratifying results.

Jan 1, 1960

By F. K. McKean

Introduction The present paper may be considered as a sequel to a paper, A Process for Cleaning Molybdenite .Concentrate, which was presented by the author at the annual meeting of the Institute last year. In that paper, a description was given of the laboratory work leading up to the adoption of a new process for treating complex molybdenite ores of the Molybdenite Corporation of Canada. A bare outline of mill performance with the new flow-sheet was included. With this writing, the purpose is to describe the highly interesting work of translating laboratory experience into mill practice, to show what changes were required in design to put the scheme on an operational basis, and to point out the gratifying improvements in mill products which resulted from the new procedure. The process has been placed in operation at the La Corne mine of the Molybdenite Corporation of Canada. This mine was operated during the war by Wartime Metals Corporation, and, earlier, by the Molybdenite Reduction Company, which installed a small plant. The property is situated on the highway from Amos to Val d'Or, Quebec. The claims held by the Company are at the boundary between La Corne and Vassan townships.

Jan 1, 1947

By C. E. St. Denis

"Training Program at Sherritt Gordon's Ruttar:. ConcentratorA formal training program for mill operators is being developed and employed at Sherritt Gordon's Ruttan Concentrator. The program was set up to fulfil the needs created by a shortage of skilled reliable labour, a 200% turnover of personnel within the first six months of operation and the rapid advances in mineral processing technology. All new employees are introduced into the Mill Department through an orientation program designed to familiarize them with the operation of the plant. All training and orientation of new employees is the responsibility of a. small training section consisting of two training foremen and one assistant. Using a combination of classroom and supervised on the job training, the training times have been cut by at least one half. High operating standards have been set and are maintained through the use of detailed manuals for each work area and competent instruction at all operating levels. The major portion of training costs arise from the salaries of the training staff but are negligible when compared to the improved recoveries, smaller turnover and less downtime. Government assistance is available to all industrial employers to offset the costs of training employees."

Jan 1, 1974

By H. J. lgner

Hydraulic fills are widely used in the tabular, steeply dipping stopes of the South African gold and platinum mines as an integrated process within a daily cycle of drill and blast. There is therefore only a small time window in which to fill the geotextile bags used as primary fill containment, without the risk of loosing production. Consequently, mines tend to increase the flow rate to the stopes, although this compromises adequate drainage, consolidation and strength development during filling. Recent underground measurements inside the geotextile bag have revealed that at high rates of rise and at 25 degrees dip, the backfill can remobilise within a limited area inside the geotextile bag during filling. This sudden downward surge of backfill exerts, for only a few seconds, additional loading on the geotextile, its supporting mesh and the props. This unstable behaviour poses a serious threat as it can push props out of place, thereby damaging the geotextile bag and causing a mud slide in the stope. To reduce the risk of accidents, the phenomenon of sudden slumping was further investigated for various filling conditions in the laboratory. The results confirmed that the maximum pressures associated with the sudden slumping can be more than five times those experienced during steady-state consolidation. Based on this new insight, the current best practice for hydraulic backfilling was critically reviewed. A practical approach to implementing meaningful standards is presented to ensure safe operations in relation to the consistency of the backfill quality and the appropriate matching of geotextile characteristics with backfill properties.

May 1, 2007

By Greg Yuriy

Over the past two decades, Vale Canada has used discrete-event simulation in a key role to support many underground mining studies. Traditionally, general purpose simulation software was developed for manufacturing and service applications. Not until recently have Mine Designers and Simulation Specialists been able to model the dynamics of underground mining scenarios without extensive manipulation of the inherent tools and entities contained within these simulation environments. This paper discusses Vale Canada?s past experiences with a variety of simulation software, describing model development methods and highlighting some of the lessons learned. The paper concludes with a review of recently considered software and provides a framework of desired attributes/functions for modeling mining scenarios.

Aug 1, 2013

By I. A. Menshikh, S. A. Kotov, N. L. Shinkarkin

All the cycle for conversion of natural and reprocessed uranium of ROSATOM’s “TVEL” Fuel Company is concentrated at the Siberian Chemical Plant. Conversion capacities are located on two sites, i.e. the Radiochemical Plant, which refines feedstock, and the Conversion Plant, which produces uranium oxides and uranium hexafluoride. Liquid radioactive waste arising in the process, after pretreatment, is transferred to a dedicated national operator for underground disposal. Environmental strategies pursued by the Fuel Company involve the introduction of process solutions intended to eliminate liquid radioactive waste and convert it into a solid phase. In the 5–7 years coming, work will be performed to refurbish and upgrade conversion facilities of the Siberian Chemical Plant that will principally change its radioactive waste management scheme. This paper describes the current waste management scheme and sets out planned schemes for management of natural and reprocessed uranium waste, which will be implemented in the refurbishment of conversion facilities of the Siberian Chemical Plant. The new technologies for the management of liquid radioactive waste from uranium conversion described in the present paper have an undeniable advantage over the current technology mainly due to significantly less environmental harm.

Jan 1, 2020

"An unparalleled growth in the Canadian coal industry in 1970 coincided with increasing awareness by Canadians of their environment and their geography with its accompanying transportation factors. R and D on coal moved with greater emphasis toward solving problems in these areas as well as continuing with strong interest in coal preparation, carbonization, combustion, ""weathering'', spontaneous ignition, storage, exploration and geology. Long-range ""basic"" research was not forgotten in that work continued on coal-based carbons, coal chemistry and agrobiological uses for coal. This paper reviews the status of these many areas of coal research at the beginning of the seventies and takes note of some of the more significant legislation and projects brought to the author's attention. No attempt is made to itemize or to describe in detail all the worthwhile projects, many of which are reported elsewhere."

Jan 1, 1971

By Minerals Refining Company, Gerald Luttrell, Biao Li, Robert Bratton, Roe-Hoan Yoon, Stan Suboleski, Nikhil Gupta

Flotation is regarded as the best available method of upgrading coal and mineral fines in the mining industry. However, its efficiency deteriorates rapidly with decreasing particle size. Furthermore, ultrafine concentrates are difficult to be dewatered economically. Due to these technological problems, some operators are forced to discard at least part of the ultrafine materials to tailings (or refuse) ponds, causing significant losses of valuable resources and creating environmental concerns. To address these technological issues, a new separation process named hydrophobic-hydrophilic separation has been developed on the basis of the recent advances in the science of hydrophobic interactions. The results obtained to date show that the process can recover and dewater ultrafine particles simultaneously with high separation efficiencies. Following a series of extensive laboratory tests, the process has been scaled up to proof-of-concept and pilot-scale continuous tests. The results obtained with desliming cyclone overflows, screenbowl effluents, and by-zero coal flotation feeds can be cleaned to less than 4% ash and moisture with over 97% organic matter (or coal) recoveries. The results obtained with mineral fines also showed encouraging results.

Jan 1, 2016

By D J. McDougall

Due to changes in the solid-state conditions of minerals in the rocks surrounding hydrothermal, contact meta-somatic or metamorphosed ore deposits, positive or negative thermoluminescent anomalies may be found in their vicinity. Several types of equipment which can be used for both quantitative and semi-quantitative measurements of the emission are discussed and compared. Methods of selecting, preparing and testing samples to ensure reproducible results are outlined, along with the kind of data which can be obtained from different types of equipment. The normal thermoluminescence of rock-forming min~ erals in the common rock types is noted, and variations in the solid-state conditions in the wall rocks which will cause marked increases or decreases of true thermoluminescence are outlined, as well as the thermolum-nescence-like emissions which are present in the vicinity of ore deposits. Introduction T HERMOLUMINESCENCE occurs when certain crystalline materials are heated to temperatures ranging between 180' and 400°C. The light emission can be ascribed to the release of electrons metastably trapped within the crystal lattice, with peak emissions taking place at temperatures which are more or less specific for a particular set of traps; the area under

Jan 1, 1965

By J. C. White

"This paper was prepared for and presented at a lecture series on ""Materials Randling"" at McGill University. The development of trackless mining at Gaspe Copper Mines, Limited is described, showing the changes in mining method and the part played by the mobile equipment in the evolution of this highly mechanized underground operation. Comparisons of loading and hauling machines are given and an attempt is made to predict some possible future developments.INTRODUCTIONTHE PROPERTY OF GASPE COPPER MINES LIMITED is located in the Gaspe Peninsula of the Province of Quebec, 60 miles west of the village of Gaspe and 25 miles south of the St. Lawrence River. The original discovery of low-grade ore was made at Copper Mountain in 1921. Subsequent exploration revealed the richer Needle Mountain orebodies, and eventually in 1951 the decision was made by Noranda Mines to build the mining, concentrating and smelting complex (Figure 1). Construction and development of the mine was commenced in 1952 and production started in 1955."

Jan 1, 1968

By B. R. Boardman

Project Environmental Approval is a multi-faceted issue. From a mining perspective, it is a costly item because of avoidable time delay. The government perspective is that the approvals are a necessary part of meeting departmental requirements to ensure that the wellbeing of other uses of the environment is maintained. This paper outlines some of the problems inherent in the environmental approvals process and makes recommendations to both the proponent and government about improving the efficiency of the process.

Jan 1, 1978

By Rick Wilkins

The stability of steep embankments is a major safety issue in open pit mining, highway passes, and earth filled dams. A failure in any one of these situations could mean a loss of very expensive equipment, a long term inconvenience, and more importantly, a loss of life. These possible catastrophes could be avoided by installing a reliable real time monitoring system. Robotic total stations (RTSs) give one possible cost effective solution to creating a near real time monitoring system. Repeated surveys at predetermined time intervals can automatically generate warnings if slope movements exceed a preset tolerance level. The variation in atmospheric refraction, combined with possible instabilities in reference targets, can make a monitoring system based on RTSs produce false alarms. A methodology has been developed at the Canadian Centre for Geodetic Engineering (CCGE) for reducing these systematic error effects. The methodology has been realized in the creation of a software package that has been successfully implemented at large earthen dams in California and at an open pit mine operation in British Columbia.

May 1, 2002

By E. Asselin, G. K. Yue

"In the present study, electrochemical measurements, especially cathodic potentiodynamic polarization (CPC) and cyclic potentiodynamic polarization (CPP), have been employed to study the kinetics of ferric reduction on chalcopyrite in aqueous Fe(II)Fe( III)H2SO4 solution at 90 °C and 110 °C. Results from the calculation of speciation in the above solution reveal that, at both 90 °C and 110 °C, the real Fe3+/Fe2+ ratio is much lower than the nominal ratio, which leads to smaller VALUES (for the reversible potential of the ferric/ferrous couple. Exchange current densities of the ferric/ferrous couple were obtained and are on the order of 106 10 5 A/cm2 a t 9 0 °C and 1 07 10 6 A/cm2 at 110 °C, respectively. The Tafel slopes from the CPP method are higher than those from the CPC method at both 90 °C and 110 °C. The transfer coefficients were about 0.360.59 at 90 °C and 0.370.65 at 110 °C. Based on the exchange current densities obtained, the rate constant kc was calculated. It was found that kc at 90 °C was slightly larger than at 110 °C, especially for the results obtained by the CPC method. The average rate constants are 862.17 cm/s for CPC and 65.30 cm/s for CPP at 90 °C, and 477.69 cm/s for CPC and 63.53 cm/s for CPP at 110 °C for nominal Fe3+/Fe2+ ratios ranging from 1:1 to 1000:1. INTRODUCTIONChalcopyrite is one of the most abundant copper-bearing minerals, accounting for approximately 70% of the world’s known copper reserves (Wang, 2005). Most of the currently proposed leaching processes are based on sulfuric acid with ferric ions and/or dissolved oxygen as oxidants. Some of these processes have been piloted in attempts to implement these technologies on an industrial scale, such as Activox (U.S. 5,232,491, 1993), Nenatech (U.S. 5,993,635, 1999), Dynatec (U.S. 5,730,776, 1998), AAC/UBC (U.S. 6,503,293, 2003), Total Pressure Oxidation (U.S. 5,698,170, 1997), CESL (U.S. 5,874,055, 1999) and Galvanox (U.S. 7,846,233, 2010).To date, much effort has been devoted to understanding the kinetics and mechanisms of the oxidative processes (Biegler & Horne, 1985; Córdoba, Muñoz, Blázquez, González, & Ballester, 2008, 2009; Ghahremaninezhad, Asselin, & Dixon, 2010; Hirato, Majima, & Awakura, 1987; Hiroyoshi, Kuroiwa, Miki, Tsunekawa, & Hirajima, 2004; Warren, Wadsworth, & El-raghy, 1982) or the cathode reduction reactions of chalcopyrite itself (Arce & González, 2002; Biegler & Swift, 1976; Biegler, 1977; Nava, González, Leinen, & Ramos-Barrado, 2008), by chemical or electrochemical methods. However, as the most important cathodic processes in chalcopyrite leaching systems, the cathodic reductions of ferric ions or dissolved oxygen are worth measuring due to their effects on the overall leaching rate, as predicted by mixed potential theory."

Jan 1, 2012

By W. J. Bennett

"I AM very happy to have this opportunity of speaking to the Montreal Branch of the Canadian Institute of Mining and Metallurgy.I have selected as the subject of my remarks transportation in that area which is at present our only source of uranium -Northwest Canada. Considering the widespread interest in atomic energy, the end-product of uranium, it may be wondered why I have not chosen to speak of a more spectacular aspect of the development. I hope it will be evident from what I have to say that transportation plays a very dominant role in our effort to maintain a continuing supply from Eldorado's producing property at Port Radium on Great Bear lake and from its coming producer at Beaver lodge Lake in Northwest Saskatchewan. Moreover, transportation has such a bearing on the entire mineral development of the Northwest that it cannot help but be of concern to an organization of this kind. Finally, the transportation problem, of which I shall try to tell you something, is quite unique and the story of its solution or partial solution is, I believe, an interesting one.Transportation experience on this continent indicates that the cheapest method of moving freight is still by water -with •rail, highway, and air transportation following, and in that order •of economic significance. Excluding rail transportation, since the area has as yet no railway lines, this order also applies in the Northwest. I shall direct my remarks to the two kinds of transportation which serve our uranium producers -water and air."

Jan 1, 1952

By L. Newman, R. Wyrick, R. Berezowsky

The Stillwater Mining Company operates an integrated mines, mill, smelter and base metals refinery complex in Montana, USA for the production of a high-grade platinum group metals (PGM) bearing concentrate, nickel sulphate crystal and cathode copper from the PGM-containing nickel-copper converter matte. The complex was constructed in stages over several years, starting with the mine and the mill, followed by the smelter and finally, a base metals refinery, which was commissioned in 1996. Due to the relatively small quantity of matte production, a straightforward refinery process was initially selected to extract the base metals, which reported to a mixed nickel-copper solution for further treatment off-site, and yielded a high-grade PGM concentrate suitable for treatment in a PGM refinery elsewhere. Subsequently, as a result of increased matte production, the process was modified to separate the nickel and copper, and to produce a nickel sulphate salt and cathode copper. This paper describes the design and operation of the original and the modified processes utilized in the base metals refinery (BMR).

Jan 1, 2004

By R. Krentz, P. D. Cordingley

The nickel-cobalt sulphides produced from limonitic laterite ores by Moa Nickel S.A. in Cuba are refined at the Corefco nickel-cobalt refinery in Canada. Major changes to the refining process were required when the Moa sulphide feed, with its unusually high cobalt content, was introduced in the early 1990's. In the period 1994 to 2005 the production capacity of the refinery has increased dramatically to match increases at Moa, and significant process improvements incorporated. The process flowsheet consists of the original ammonia leach process, optimized for cobalt chemistry and overall leaching capacity. Extraction of metal values is followed by the unique nickel-cobalt separation technology, in which most of the cobalt is separated from the ammoniacal nickel sulphate leach solution by precipitation as a nickel-cobalt hexammine salt. This salt is refined from a Co:Ni ratio of 1:1 to over 10,000:1 by selectively leaching nickel, redissolution and recrystallization in ammonium sulphate solution. Nickel and cobalt are recovered using the well-known Sherritt hydrogen reduction technology. This paper reviews the chemistry described above, examines some of the changes in operating conditions made over the years and highlights some of the recent physical changes made to the refinery.

Jan 1, 2005

By V. E. Dawson

Brake testing of large mining trucks was initiated in British. Columbia in 1969 following an accident involving the failure of the service brakes of a l00-ton electric-drive truck. Some selected results of the 1976 brake test program are presented and discussed ?in this paper . The tests were conducted on end- dump trucks having load capacities ranging from 85 to 235 tons. All tests were made with the vehicles fully loaded operating on downhill grades varying from 8 to 10 %. Stopping distances were measured from initial speeds varying between 10 and 39 mph. The results are adequate, in most cases, to determine the "ultimate" capabilities of the service brakes of varying models and sizes of haulage trucks operating in British Columbia mines.

Jan 1, 1977