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By J. R. Smith

"The Lake Dufault orebodies were discovered by deep surface diamond drilling. When a reasonable amount of outline drilling had been completed, the decision to go into production was made. The fact that shaft sinking, lateral development, the detailing of the orebodies and stope preparation were to be carried out as rapidly as possible necessitated very close scheduling.After a study of varions possible mining methods, an open-stoping system using long-hole blasting was chosen. Diesel-powered Transloaders were selected for the mucking and transportation of ore from the drawpoints to the orepass.At the time of writing, the choice of mining method appears to have been fully justified, although more time will be required to arrive at true operating costs and efficiencies."

Jan 1, 1966

By John Porritt, Alain Dorval

"TioMin Resources Inc. is evaluating the feasibility of exploiting the heavy mineral sands deposit at Natashquan on the north shore of the Gulf of St-Lawrence, Quebec. TioMin holds the exploration rights to 180 square kilometres, on which 1.6 billion tonnes of sands grading approximately 6% heavy minerals were outlined. The heavy minerals of value include magnetite, ilmenite/hematite, garnet, and zircon. An important part of this evaluation is the development and testing of a mineral separation flowsheet. Under a comprehensive mandate from TioMin, the Centre de recherches minerales (CRM) provided technical assistance to build and operate an on site primary concentrator pilot plant. This plant produced a 93 tonne concentrate, providing over 60 % heavy minerals. This concentrate was shipped to the CRM pilot plant in Quebec City. It was used for further flowsheet testing and for preparation of products and concentrates of heavy minerals with regard to marketing possibilities. This paper presents the flowsheet developed to produce these concentrates.IntroductionIn late 1992, an 11 tonne bulk sample of sand was collected from within the mineralized zone of the Natashquan deposit. This sample was processed over conventional spirals and wet tables at the pilot plant facilities of the Centre de recherches minerales (CRM) in Quebec City. A primary concentrate was produced, from which several 20 kg samples were forwarded to five research laboratories in North America and in Australia. Their tasks were to determine the mineralogical composition of this concentrate and the potential for recovery of marketable minerals from the heavy mineral sands. Satisfactory results obtained from this approach encouraged TioMin to proceed with a more detailed pilot plant program."

Jan 1, 1995

By Kosei Ishida

To achieve renovation work without noise, the authors developed techniques of manufacturing pre-cut interior finishing components for renovation work. In this paper, to achieve the system of pre-cut interior finishing components, the authors describe a measuring method of reinforced-concrete structure by 3D laser scanner and then describe a method of making a design of pre-cut interior finishing components with the polygon model. Using these two methods, the steps of manufacturing pre-cut interior finishing components consist of the following four steps: First, measure the building shape using a 3D laser scanner. Secondly, integrate a point cloud data and retrieve the markings on the floor. Then, create a polygon model of the building based on the point cloud data. Lastly, make a drywall design using a polygon model. To evaluate the technique feasibility of manufacturing pre-cut interior finishing components, the authors have conducted an experiment of the finishing interior work of the drywall. Using pre-cut interior finishing components, the authors have been able to achieve interior finishing work without noise.

Aug 1, 2013

By W. B. Morrey

"In recent years, the major effort in detonator development has been concentrated on ""non-electric"" systems. Existing types all involve some form of explosive reaction to transfer ignition energy from outside the borehole to the pyrotechnic delay element contained within the detonator. These may be based on low-energy detonating cords having grained or plasticized explosive cores, shock tube energy transmission principals and explosive gas ignition systems. Each has properties of internal and external effects not present in electric conductors.The MAGNADET System introduces transformer coupling into electric blasting circuits. Safety features with respect to current leakage, stray currents of AC or DC source, electrostatic energy and radio-frequency radiation are comparable to ""non-electric"" systems, with advantages in simplicity, speed of hook-up and range of application.The transformer device used is a small ferrite ring or toroid which is an integral part of each specialized detonator. The detonator legwires form the secondary side of the transformer winding. The primary side is a single wire loop common to all units within the circuit. Power is supplied from a frequency-tuned portable exploder with unique circuit-sensing features.The MAGNADET System is expected to have particular application to shaft sinking, raising and tunnelling where the protective features as well as speed and efficiency are critical factors. Applications of the 'MAGNA' booster in quarries, open pits and longhole deck charges offer control over vibration problems and elimination of surface noise.IntroductionFor many years, electric detonators and electric blasting systems dominated surface and underground applications where controlled delay times were required. Control over the instant of detonation by blasting machines or power-line switches is the major safety feature.Electrical energy exists in many forms. It may originate from many sources. Electrical energy can be difficult to contain. It may enter or escape through a variety of conductive paths. It may fluctuate, concentrate or dissipate to pose a most elusive potential hazard."

Jan 1, 1982

By R. G. Achter, E. Wilson

"This paper describes the work undertaken to renovate the Pipe Open Pit drainage system, incorporating measures to improve effluent quality. It describes the technical feat of drilling an l l-inch-diameter hole from the bottom of the open pit for a distance of 1100feet to intersect an underground drift. An innovative method of checking the inclination of this hole is also described. The paper outlines the construction required on the 1500-foot level of the underground mine to facilitate water impoundment and slime settling, as well as the instrumentation for control of water flows. IntroductionThe Manitoba Division of Inco Metals Company operates two mines-an underground mine at Thompson and an open pit at Pipe. The Pipe Open Pit is located 20 miles southwest of the City of Thompson, approximately 400 miles due north of Win nipeg(Fig. 1).Surface diamond drilling of the Pipe ore body was sta rted in 1959. In 1961, a shaft was sunk to a depth o f 1,570 feet to carry out further exploration work and obtain bulk ore samples for metallurgical testing. Site preparation to mine the upper portion of the orebody as an open pit was initiated in 1966 and by late 1967, the removal of silt and clay overburden was in progress. The contractor completed the dredging in the fall of 1969. Over 12 million cubic yards of muskeg, clay and silt was removed, which in some places was 150 feet deep over the orebody. Production began in early 1971, by which time the top three benches of rock had been excavated and the orebody exposed.The Pipe No. 2 Mine main shaft was started in 1970 and completed in 1973 at a depth of 3,160 feet. Development for exploration purposes was carried out on the 1500 and 2460 levels, and permanent pumping facilities were installed.The surface dimensions of the open pit are 2,200 by 1,600 feet, with the long axis striking northeast. The walls are designed with a 45- to 50-degree slope and the ultimate design depth is 720 feet. The present depth of the pit is 520 feet and production capacity is 6,800 tons of ore per mine day."

Jan 1, 1980

By Éric Côté

Introduction The 425 Main Ore Zone ? Block of ore partially mined in the late sixties; ? Area was sealed off for over 30 years due to SO2 emissions from oxidizing fill material; 425 Project goal ? Bring the zone back into production without jeopardizing the mine; ? Minimize risks associated to SO2;

Feb 1, 2008

By A. B. Szwilski

The paper outlines the factors taken into account for the selection of steel arch supports. The results are based on experience using the long wall system of coal mining where roadway closure can be extreme. Results of tests on scale-model steel arches and full-scale yield elements are also presented.

Jan 1, 1979

The control of carbon concentration in a counter current carbon absorption circuit is critical to optimise gold recovery. MINTEK has developed a carbon movement controller to address this potentially problematic area in gold extraction. This controller reduces operator interaction by automating carbon movement. Elution schedules are entered into the control system, which then moves the carbon through the circuit into the first adsorption tank until enough carbon is available for elution. This is done while maintaining the specified carbon profile within the circuit. MINTEK has also developed an online-carbonconcentration- meter to measure carbon concentration in pulp. The meter uses an ultrasonic measurement technique. Long term testing has shown the measurement to be robust and require minimal maintenance. Results from a gold mine in South Africa’s well known Witwatersrand gold producing area has shown a decrease in soluble gold loss between 30 - 50% when the controller was used.

Jan 1, 2014

By Jean-Luc Collins

"The paper deals with the impact of fleet imbalance on a deterministic evaluation of shovel fleet productive capacity. It shows that if the fleet imbalance is overlooked, then estimated fleet productive capacity will be overrated.The paper shows that fleet imbalance inflates utilization, and care must be taken when using such statistics which are derived from reported field-equipment-hours. It shows that the utilization must be deflated by a factor called 'balancing efficiency"" in order to estimate shovel productive capacity correctly. The paper also shows how fleet imbalance can be controlled by managing idle time or downtime in an actual operation.The technique used for measuring the balancing efficiency factor is based on statistical analysis of equipment utilization."

Jan 1, 1980

By Juergen Antrekowitsch, Stefan Steinlechner

"Waelz oxide from steel mill dust recycling is usually sold to the primary zinc industry, where it is first charged to the roasters to eliminate the remaining fluorides and chlorides. This limits the overall amount of secondary materials which can be used because of different operating problems in the roasters. Another option, in the case where the halides are low, would be direct leaching with low or medium concentrated sulphuric acid. Unfortunately, because of the carryover of some steel mill dust, iron is also present in the Waelz oxide, reaching contents up to 5 wt.%. Since the objective is to treat the solution more or less directly by electrowinning, with only a few simple preliminary purification steps, iron in the solution is a very important factor. Various trials have been done to investigate the dissolution behavior of the iron contained in the Waelz oxide. Although the zinc extraction should reach a maximum, all other elements, especially iron, should be low. This paper describes the results of our research in this area and offers possible options for Waelz oxide utilization. There is also a focus on how other elements, present in the material, influence the dissolution behaviour of zinc and iron, and whether a loss of zinc is unavoidable, if low iron dissolution is required.INTRODUCTION One of the most important secondary zinc resources is the zinc oxide originating from steel mill dust recycling. For the treatment of high zinc containing steel mill dusts, the Waelz kiln process is the so called “best available technology” and it dominates the industry, with roughly a 90% market share. The product Waelz oxide contains mostly zinc oxide, but it also contains lead compounds and halides due to evaporation with the zinc. In addition, it contains iron and some slag compounds due to mechanical carry-over. The presence of halides limits the use of the material as an alternative concentrate for primary zinc electrowinning. Such halides can be reduced to a certain extent by washing and/or solvent extraction (see following chapter). Although lead is not troublesome and theoretically represents a second recoverable valuable metal, iron is unwanted and causes additional problems during leaching. Even though Waelz oxide is generally a highly welcome input material in primary zinc metallurgy, due to its high zinc content, it still contains halides, and in the majority of cases, the oxide must first be treated in a roasting process. Different circumstances, like accretion formation because of the lead and halogen compounds as well as unwanted cooling effects in the roaster, limit the amount of Waelz oxide which can be substituted for the primary concentrate. Another, even more limiting factor, is the allowable concentrations of chlorides and fluorides in zinc electrowinning, the last step in the primary zinc processing route (Ruetten, 2011)."

Jan 1, 2016

By Nigel Saunders, Zhanli Guo

"Quench sensitivity of heat-treatable aluminium alloys is closely related to the precipitation process taking place during quenching. Faster cooling results in less precipitation of coarse phases during cooling, leaving more solutes in the solution before ageing. An alloy in such state would be of greater hardening potential as larger amounts of hardening phases may precipitate out during ageing. Hence, to understand the quench sensitivity of an alloy, it is essential to understand its precipitation process. Precipitation is a diffusion-controlled process and the diffusion is made complicated by the so-called quenched-in vacancies. These vacancies form during solution treatment, become “excess” when temperature goes down, and annihilate during the following cooling and ageing treatments, making diffusion now a function of both temperature and time. This paper first investigates the formation and annihilation of quenched-in vacancies and their effect on diffusion. The diffusion affected by quenched-in vacancies is considered in the kinetic models to realise the calculation of TTT/CCT diagrams for aluminium alloys. The calculated CCT diagrams have been used to explain the observed quench sensitivity and age hardening behaviour of various commercial alloys. The transformation from GP zones to other hardening phases during ageing is also discussed.INTRODUCTION The heat treatment of aluminium alloys mainly consists of three stages: a solution treatment at an elevated temperature, quenching from this solution treatment temperature to room temperature, followed by an ageing treatment to allow the precipitation of strengthening phases(Davis, 1993).The following statements generally describes how quench sensitivity is observed in heat-treatable Al-alloys: faster cooling results in,(i) less precipitation of coarse phases formed at high temperature during cooling, (ii) more solutes kept in solution before ageing, and (iii) larger amounts of hardening phases being formed, i.e. a greater hardening potential. Thus, the quench sensitivity of an alloy is closely related to its precipitation kinetics."

Jan 1, 2018

Presentation Overview ?WRDC Purpose and Activities ?Women in Trades, Technology and Operations (TTO) Occupations ?Factors in Successful Recruitment / Retention of women (VBNC) ?Recruitment and Retention Strategies ?Conclusion Women in Resource Development Committee (WRDC) ?Incorporated in 1999 as a Not for Profit Organization ?Based in Newfoundland and Labrador ?Works to Increase the Participation of Women in Natural Resource Industries ?Research (Using Gender-Based Analysis) ?Career Exploration Programs for Women and Girls ?Outreach and Advocacy ?Policy Development ?Public Awareness and Education ?Gender Sensitivity Training ?WRDC Educational Resource Centre

May 1, 2006

By Werner W. Scholz

A corrosion-resistant lining is, quite often, selected on the merits of its corrosion resistance only. This paper demonstrates the effects of temperature, pressure, weather, design aspects and variances of physical properties within the scope of the generic designation of a corrosion-resistant material or materials. The base for the study is a rubber- and brick-lined steel vessel, with unchanged chemical conditions. Graphs and sketches illustrate the various effects of physical influences on the selected lining specifications.

Jan 1, 1979

By R. C. Bryce

"Accident prevention has been an on-going priorty for five years. In 1987, adherence to the ILCI five-star rating loss control program was started, and a first star was awarded. Extensive training programs have been undertaken to establish standard procedures and upgrade employee skills. Due to its location, Selbaie owns and rents housing in the town of Joutel and contracts a busing service to and from the mine. Employees from other areas are lodged in dormitories and fed in the site dining room. Accounting and warehousing services are carried out in efficient fashion. Employee relations are structured to provide prompt resolution of complaints and differences. No lost time due to industrial relations differences has been encountered during the history of the mine.Safety and Loss ControlAll mines are concerned and occupied with a wide range of activities to ensure the safety of its employees. Selbaie is no exception. Programs to achieve success in safety and loss control have been implanted since the start of construction and development at Selbaie and have followed three interesting stages of evolution."

Jan 1, 1990

By H. Langlois

"Included in the Mines Gaspe mining complex located at Murdochville, Quebec, is a copper smelter which comprises a reverberator furnace, two Peirce-Smith converters, an anode furance, and a sulphuric acid plant.The 50% smelter capacity available is supple mentedby custom concentrates for treatment. As these concentrates can be varied and extremely complex many modifications and improvements have been brought about to optimize and make the process more flexible since its inauguration in 1955.IntroductionThe copper smelter of the Mines Gaspe mining complex is located in Murdochville, a small municipality in the heart of the Gaspe peninsula, 90 km northwest of the town of Gaspe .This metallurgical installation has a daily smelting capacity of 650 tonnes of concentrate and an output of 250 tonnes of copper and 900 tonnes of sulphuric acid. Its main components are: a reverberatory furnace, two Peirce-Smith converters, one rotary anode furnace and one acid plant. The gases, which are produced by the converters, are treated at the acid plant then combined with gases from the reverberatory furnace before being vented through a 152 metre high stack .From the beginning of its operation until the present day (1991), the smelter has treated 7 million tonnes of concentrate and 100 thousand tonnes of scrap for a production of 1.8 million tonnes of copper and 2.2 million tonnes of sulphuric acid."

Jan 1, 1993

By Arthur Lieu

Outline Removal mechanisms of Se and Mo in the Key Lake Bulk Neutralization circuit Bulk circuit Detail process modification in the Key Lake BN circuit Process performance after commissioning Objective Legacy effects of Se and Mo from the historical operation of Key Lake mill were shown to have an negative effect on the regional biota in the downstream environment. The water treatment circuit was not designed to remove Se and Mo from the effluent. Reduce Se and Mo concentrations in final effluent under0.028 0.028 ppm ppm and 0.3 and ppm ppm(CNSC regulatory limits).(limits).??????

Nov 1, 2011

By So-Yeong Lee, Moosang Lee, Seung Hwan Ahn, Ho-Sang Sohn, Jongshin Chang

It is necessary to understand the characteristics, phase changes and chemical reactions of flue dusts introduced from a furnace to an off-gas line in order to achieve the stable operation and the improvement. This study is to develop the dust reaction model for chemical reactions of dusts in an uptake shaft of smelting furnace and a waste heat boiler. Phase equilibria and reaction paths in this system were determined by thermodynamic calculation with experimental and industrial data. The oxidation reaction rate of dusts was determined by the gas film mass transfer controlling. And the sulfation reaction rate was evaluated by the unreacted shrinking core model. Kinetic parameters were estimated by reference data including industrial ones. The present study with the developed model shows various effects of temperatures, dust particle sizes, and O2 gas partial pressures on dust reactions. INTRODUCTION The flue dusts from a copper smelting furnace move along a furnace off-gas stream into an uptake shaft and a waste heat boiler (WHB) and electrostatic precipitator(s). It is necessary to control the dust quality in order to stabilize the operation because the sticking behaviors differ depending on the phase of dusts. Phase changes of dusts are caused by chemical reactions at given conditions such as temperature and partial pressure of gases. Therefore, it is required to understand the phase changes and chemical reactions of dusts in order to perform the improvement and stable operation. The present study carried out the investigation to understand their fundamental knowledge. Especially, this study was focused on the kinetics of chemical reactions of flue dusts, developed the model. In particular, the scope of development and utilization of the model was defined as the uptake shaft of the Mitsubishi S furnace and the S-WHB radiation section in the Onsan smelter. Information needed for the modeling work referred to data from these processes.

Jan 1, 2019

By V. Itkin

"Three methods were tested for the beneficiation of aluminum scrap, generated by heavy medium separation of non-ferrous automobile scrap residue. These were: crushing in a shredder followed by screening; grinding in a ball miff followed by screening; and eddy current separation. The best results were obtained with the grinding-screening method. IntroductionThe usual method of aluminum alloy reclamation from non-ferrous automobile scrap residue consists of a two-step heavy medium separation to remove materials lighter than and heavier than aluminum. The resulting aluminum scrap still contains over 15% impurities such as stones and glass, heavy rubber, insulated copper wire , plastics and heavy metals entrapped by macerated aluminum piece s, composite fragments, etc.(2). Upon melting, these impurities create difficulties and yield a low ingot recovery-65% to 70%, hence small foundries avoid this material.There are a number of ways to improve the quality of aluminum scrap such as:(1 ) crushing of the scrap, which powders the brittle content , a major impurity component, followed by screening out of the dust(2) eddy current separation , which removes metals from the material flow, and(3) implement better methods for density separation.The eddy current separation and two variants of the comminution-screening technique were studied by Intermetco Ltd., Hamilton , Ontario."

Jan 1, 1986

By H. M. Howard

"The subject of Grinding Media is perhaps still quite controversial. Many people will state today that the spherical ball is the only way, and also will state that this was settled long ago others are not so sure, and I am in this second category. Over the years there have been many changes in grinding and in our evaluation of grinding media we should always be ready to review the overall situation at regular intervals. There is quite a lot of inertia in all branches of Hineral Dressing and this is particularly true of grinding or, more correctly, comminution.In order to understand some of the things which are done today, and to understand some of the thinking on grinding, it is desirable to go back some sixty years and trace the developments in comminution. In doing this we should consider perhaps three general categories with respect to daily tonnage. An arbitrary division would be under 500 T.P.D., 500-5000 T.P.D., and large operations which might have several parallel units, each with a capacity of about 5000 T.P.D. For the future, in the broad picture, this last category will be the important one because we will be more and more dependent on large-tonnage low-grade operations for most of the metals of the future. Some such division is necessary because the daily tonnage will have a very great effect on what we can and cannot do. It is also necessary to consider the entire flowsheet, and to remember in particular that grinding is not merely to make small particles but is also a conditioning process, to prepare the materi.al for the process which follows. The relationship of crushing to grinding must also be considered. It is logical to include the liners as part of the grinding media and we should try to distinguish between the wear of grinding media and the consumption of media by corrosion. Finally, the whole question of grinding media should be examined in relation to the possibilities of using some form of autogenous grinding."

Jan 1, 1970

By Navid Bahrani

Introduction ? Today?s economic market is motivating underground mining companies to increase development advance rates and enhance their NPVs. ? For example, block cave mining involves development of kilometers of drifts with multiple pillars. ? The cyclic nature of drill and blast, and its inherent tendency to damage the surrounding excavation rock mass and increase support demand often result in poor advance rates ? This has motivated mining companies to replace the conventional drill-and-blast as the main excavation method with alternative methods such as mechanized excavation. ? There is little experience with mechanized or non-explosive excavation methods in hard rock metalliferous underground mining.

Oct 1, 2010