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By J. K. Atherton

If the metals sector is to contribute successfully to sustainable consumption we must adopt principles and practices which address the entire life cycle of the materials we produce. Progress must be founded on a sense of shared responsibility for the resources we utilize and the materials we create - it is this integrated approach which lies at the heart of materials stewardship. Materials stewardship means mining and metals companies producing materials in a responsible manner and then working with others, beyond their site, to ensure that the downstream material flows and applications are managed properly to create maximum societal value. In September 2006 ICMM published 'Maximizing Value: Guidance on implementing materials stewardship in the minerals and metals value chain'. This document takes a practical view presenting structured guidance as well as good practice case studies. In the publication, materials stewardship is described in terms of the range of activities that can be undertaken to ensure that all parties work collectively toward the responsible use of metal and mineral resources. This paper introduces the materials stewardship concept as set out in `Maximizing Value' and describes the business case for implementation as well as the ICMM framework for promoting materials stewardship.

Jan 1, 2007

By J. Costigan, C. Corless

In 1997, damage as a result of Castrol R40 entering the INCO pressure carbonyl plant carrier gas stream was becoming increasingly severe. The oil in the gas stream was adversely affecting both equipment availability and process control resulting in rising unit costs. The main source of the Castrol R40 was determined to be the carrier gas and low pressure gas blowers. Plant personnel initiated a plan to prevent the Castrol R40 from entering the carrier gas stream by replacing the mechanical shaft seals with Ferrofluidics seals on these blowers. The following paper details a brief case history of the Castrol R40 in the carrier gas including impact on the plant. This will be followed by a technical discussion of the new sealing arrangement that was developed by plant personnel, Roots Blower and Ferrofluidics. Lastly, this paper will update the status of the blower upgrade project and document the results to date.

Jan 1, 2000

By A. C. Stevenson

"The most common theory is that, since thyristors, diodes, and insulated gate bipolar transistors (IGBTs) are “solid state” they will live forever. This is not so. They have wear-out mechanisms (e.g. insulation) and other mechanical parts such as motor bearings. These wear-out phenomena can be easily calculated. In this paper we will look at some of the failures and the failure rate of thyristors in power converters to see what affects them and to see what improvements can be made. If converter failures do occur, some simple forensic engineering steps will show if this is the root cause of the problem.IntroductionLook at the general failure rate curve for thyristors, diodes, gate turn off devices (GTOs) and IGBTs shown in Figure 1. We see that there is an initial high failure rate due to manufacturing defects, application problems, and drive start-up stresses that lasts for a few weeks. This is followed by a long period of (hopefully) several years with a relatively low but very slowly rising failure rate. At the end of this period, the devices start to wear out and the failure rate suddenly starts to increase rapidly over a few months. This signals the end of life for the devices in the system. We will start by looking at this end of life area."

Jan 1, 2000

By C. J. Cajka

Commodity agreements, trade liberalization, producer cartels, the New International Economic Order, price stabilization and access to supply are buzz words of the day. The international concern and dialogue on these concepts, often by a new breed of politically motivated experts, have generated intense interest in seeking an international solution to natural resource problems. While this momentum was maintained during the past year, the growing incidence of protectionist actions by several major nations has been eroding confidence in the global approach. The seriousness of current difficulties has created an urgent need for decisive action. At the same time, the limitations of the global approach have become more evident.

Jan 1, 1978

By P. Z. Caverhill

In this section of the province only the most meagre of surveys have been made and because these are not sufficient to determine with any degree of accuracy even the total forest area, the information presented in this paper is not complete. Area: -The area south of the Canadian National, and served by the Pacific Great Eastern, is roughly 38,000. square miles, 30,000 of which is classed as productive. This is approximately equal to the productive area of Norway, or half of Finland-or of 30 per cent of Sweden. It is larger than that of either Nova Scotia or New Brunswick. Eliminating from the productive area 3600 square miles of grass-land and areas capable of agricultural development, 26,000 square miles (16,600,000 acres) remains as absolute forest-land, as compared with the 55,000,000 acres of Sweden, the 37,500,000 acres of Finland, the 17,000,000 acres of Norway, and the 7,600,000 acres of Austria.

Jan 1, 1925

By J. B. Mitchell

Many of the pre-production and plant startup problems that we regard as inevitable are actually caused by poor organizational methods. Traditional methods of organization can be modified to provide clear definitions of responsibility, continuity and depth of involvement of key personnel in order to overcome these problems.

Jan 1, 1966

By R. L. Christie

"THE ISLANDS lying north of the Canadian mainland, and the large Boothia and Melville peninsulas, form one of the great archipelagos of the world; this sparsely vegetated and nearly unpeopled region extends about 1,500 miles east to west and 1,200 miles from the mainland to the northern tip of the northern-most island. Sea access to most of the islands is restricted by ice to the summer season, and the 'polar pack' ice of the Arctic Ocean presses the year round against the northwest margin of the archipelago. Although the region is remote, the accessibility has greatly increased through a network of weather stations, airfields and air routes connecting with southern centres.The area considered in this paper is that part of the island region underlain mainly by sedimentary rocks. In broad terms, this includes the land and sea areas of the archipelago and the adjacent continental shelf, but excludes the dominantly 'Shield' terrain of Baffin Island, and of Melville and Boothia peninsulas. An impression of the size and potential of this sedimentary region may be gained by comparing some areas: the land area of islands underlain mainly by sedimentary rocks is over 300,000 square miles or about 50,000 square miles greater than the area of Alberta. The total area of the region, including the continental shelf and the inter-island areas, may be double this figure, and may approximate one-seventh of the land area of Canada."

Jan 1, 1970

By Ian E. Efford

The paper gives an assessment of Canada's energy supply-and-demand position, the current situation and projections into the future, as well as a review of some alternative energy futures for Canada. The main elements of Canada's energy strategy for the period 1977-1990, with particular reference to the role of energy conservation, are discussed, leading in to the development of the national energy conservation program.

Jan 1, 1977

By B. R. Bowerman, W. J. Thoburn, M. J. Humphris

"Nickel granules are produced for carbonylation by pouring a molten stream into a path of high pressure water. Granules and water are separated in dewatering bins. The overflow, which contains up to 0.1 weight percent solids, was initially cooled and recycled to the granulating step. However, the rate of buildup of these solids in the handling system was intolerable. A lamella thickener was installed to solve the problem by removing solids from the dewatering bin overflow. Its description, application and performance to date are discussed.The lamella thickener treats a slurry containing about 0.1% solids of which about 30 weight percent is less than 325 mesh. It recovers 80 to 90 percent of the input solids in an underflow slurry containing 90 weight percent solids. Since its installation the frequency of cleanout of the recycle water handling system has dropped from about once per month to about once or twice per-year."

Jan 1, 1977

By R. Holmestad, M. Gazizov, S. Wenner, R. Kaibyshev, J. K. Sunde

"Mechanical properties and microstructure of an Al-4.7Cu-0.74Mg-0.51Si-0.48Mn-0.10Cr-0.09Ti-0.02Fe (wt. %) alloy subjected to various thermomechanical processing (TMP) have been investigated and compared to conventional ageing at 170°C (designated T6). Three TMP routes involving cold deformation of solution treated samples were tested. These were (i) 3%-stretching (T8-3%), (ii) equal-channel angular pressing (ECAP) to true strain (e) of ~1 (T8-1) and (iii) ECAP to e~2 (T8-2), all with subsequent ageing at 170°C for 0-96 h. At peak age conditions, both yield stress, ultimate tensile strength and elongation-to-fracture decreased for the T8-3% state as compared to the T6 condition. Intermediate ECAP (T8-1 and T8-2) lead to significant increase in maximum yield stress, ultimate tensile strength and elongation-to-fracture. The changes in mechanical properties were related to microstructure evolution, encompassing changes in grain sizes, dislocation densities, precipitate morphology and phase fractions, which were characterised using transmission electron microscopy. Relations between TMP, precipitation behavior and contributions to different strengthening mechanisms are evaluated.INTRODUCTION Al-Cu-Mg-Si alloys are widely used as structural materials in aerospace industry due to their attractive combination of high specific strength, good fracture toughness and enhanced creep resistance. These properties are largely due to the formation of a large number of nano-sized metastable precipitates during artificial ageing (Polmear, 2006; Eskin, 2003; Gazizov, Dubina, Zhemchuzhnikova, & Kaibyshev, 2015). The precipitation behaviour in these alloys is complicated and depends among other things on Cu concentration and the Mg:Si ratio (Wolverton, 2001; Chakrabarti, & Laughlin, 2004). In general, the precipitation sequence has been presented in a prior study (Eskin, 2003) as follows:"

Jan 1, 2018

By Frederic Benard

THE Ontario Refining Company, Limited, wholly-owned subsidiary of The International Nickel Company of Canada, refines the entire blister copper output of the latter's Copper Cliff smelter. Prior to 1936, the blister was cast in 460-lb. cakes at the smelter, loaded on open cars, and transported by rail to the refinery, a distance of approximately 1 1/4 miles. Here the cakes were transferred to the plant narrow-gauge system, charged to furnaces, and re-melted. This procedure necessitated the operation of holding furnaces and casting machines at the smelter -extensive re-handling-and melting down of a cold charge at the refinery. Transfer of the copper in molten form direct from converters to anode furnaces promised a considerable reduction in costs, and this possibility was investigated. As a result, a portable holding furnace, or hot-metal car, was designed and constructed. It was placed in operation in July, 1936, to be followed a year later by three additional units of slightly modified design. Figure 1 shows the original car, and Figure 2 the lacer type. With four cars in service, operations were placed on an all 'hot-metal' basis.

Jan 1, 1938

By A. Flemming

"As the next century draws near, new mine properties must be brought into production to replace existing operations that are approaching their economic life. This paper presents some of the critical technical issues being addressed by Manalta Coal Ltd. as they strive to bring the Telkwa Coal Project near Smithers, BC into production during the year 2000. The mine is planned to produce between 1.0 to 1.5 million tonnes per year of medium volatile coal for export to overseas thermal and PCI markets. IntroductionManalta Coal Ltd. (Manalta) is proposing the development and operation of a surface coal mine and associated infrastructure approximately six kilometres southwest of the village of Telkwa, British Columbia (Fig. 1). The infrastructure consists of a coal washing facility, tailings disposal area, clean coal haul road, access road and rail loadout facility. Over a 25-year period, the mine is expected to produce between 25 and 37 million clean tonnes of coal primarily for the export market.To achieve public and governmental approval for the development, the project will be reviewed under British Columbia’s Environmental Assessment Act. Manalta entered the formal Assessment process in February 1, 1997 with the submission of an Application for a Project Approval Certificate for the Telkwa Coal Project."

Jan 1, 1997

By Saikat Chatterjee, Xintong (Brett) Liu, Kinnor Chattopadhyay

Magnesia carbon bricks are commonly used in BOFs and are generally pre-heated before the BOF goes into service. Owing to very stringent emission regulations, the BOF pre-heating process need to be controlled and optimized so that, the emission standards are met. One of the major concerns in organic emissions are its stringent limits on emission rates and total volatile emissions. In the present work, an attempt has been made to integrate CFD and Thermodynamic models to predict the emission rate of volatile organics during the pre-heating process. A one dimensional heat transfer model was developed using visual basic and then integrated with thermodynamics calculations using FactSage 6.4. The parameters that affected organic emissions were the pre heating procedure, gas composition of the burner, heating rate and type of the burner. Typical composition of MgO-C bricks and binder materials were obtained from literature and vendor data sheets. Chemical reactions between organic materials, refractory and burner gasses were considered. The model predictions indicated that certain burner conditions could destroy all organics before it exits the vessel while other conditions needed the use of an after burner at the mouth of the vessel. The model was also able to predict the organic emission rates based on the chosen pre-heating profile. This kind of predictive model will be very useful for the steel industry and enable them to justify permit limit applications and stick to the limits by fine tuning their pre-heating process.

Jan 1, 2015

By V. A. Chanturiya, T. N. Matveeva, N. K. Gromova, T. A. Ivanova

"The research is aimed at solving the problem of increasing the extraction of gold from refractory ores, which are the main source of growth in gold production in the next decades. The purpose of the research is the development and scientific substantiation of the reagent modes for flotation extracting of gold from refractory ores using eco-friendly low-cost herbal modifiers (HM), providing increase in gold recovery and quality of gold concentrates. In the course of research laboratory techniques for the preparation of experimental samples of HM were developed, which included the sequence of operations of grinding Heraclium leaves and stems grinding, 2-stages extraction at a temperature of 50-60 °C, short-term ultrasonic treatment, filtration and subsequent unification of extracts. According to the developed method, the experimental samples of HM and conducted research were tested to analyze their sorption and flotation activity related to the extraction of gold from refractory gold ores.New data on adsorption and flotation properties of Heraclium stems and leaves extracts (HSE) in selective flotation of Au-sulfide minerals were obtained using UV-spectroscopy, scanning electronic and laser microscopy and atomic force microscopy. The dimensions and shapes of adsorbed hydrophilic films of herbal reagents were identified and mechanism of formation of stable insoluble compounds on the surface of minerals in flotation was explained.Research flotation tests carried out on samples of refractory gold ore of one of Russia deposits showed the possibility of effective use of herbal modifiers to improve qualitative and quantitative indicators of enrichment compared with the standard reagent regime. New reagent modes, using herbal modifiers in an amount of 5 to 10 ml of the extract (300 - 600 g / t, respectively) improves the quality of the concentrate: gold content attains 14.7 g / t, 1.34 times higher than in the baseline experiment and provides a gain of 3.13% extraction.The developed reagent regime with herbal modifiers is the author's original design, patented (patent of the Russian Federation) and have no analogues in the world of mineral processing. (Application number 2015116125 from 04.28.2015, ""The method of flotation separation of sulfide minerals using herbal modifier"", Russia). Actual application of new plant extracts as modifiers in flotation of sulfide minerals is the possibility of replacing of highly toxic chemical compounds by environmentally safe substances of plant origin. Implementation of the developed methods of extracting gold from refractory minerals with herbal modifiers will help to improve gold recovery at 3-5% and the quality concentrate of not less than 1.2 times, leading to higher productivity and a reduction of the negative man-made effects on the environment ."

Jan 1, 2016

By E. Gaucher, D. C. Gagnon

"The paper refers to methods and concepts used in the computer treatment of banks of geophysical, geochemical and geological data, relating to the exploration of massive sulphides. In particular, a data bank of 400 drill holes on independent conductors can be used to calculate probability levels of intersecting a certain quantity of sulphides according to the characteristics of the conductor. Inversely one can, using the data bank and some cost assumptions, simulate and optimize the cost of intersecting a certain quantity of sulphides by selecting drill targets among conductors according to conductivity, magnetism or gravity. Problems of noise, inherent in any simulation, are illustrated in this paper by the results of a study of the nomenclature of volcanic rocks of 27 drill holes by forty geologists. Compilations of data banks are long and timeconsuming, and it would help to standardize to allow exchange of data. We believe that such efforts may result in the discovery of more mineral deposits and at a lower cost. The present study is supported jointly by SOQUEM The New Jersey Zinc Co. and Cominco Ltd."

Jan 1, 1973

By A. Golpaygan

Application of Computational Fluid Dynamics (CFD) modeling for simulation of fluid flow and combustion in industrial scale electric furnace is presented. Poor combustion efficiency, roof and/or side wall overheating, carry over to off-gas system and non-ideal radiative heat transfer to processes or cooling systems have been common limiting factors causing inadequate process performance of the furnace, operational problems, and safety hazards. This paper describes how CFD analysis can be used to obtain a better understanding of commonly observed problems associated with freeboard combustion. Examples are presented to describe using combustion CFD modeling to understand requirements to diagnose a problem with furnace design including required freeboard volume or possible roof/side wall overheating.

Jan 1, 2011

By G. Van Weert

In the spring of 2010 double refractory ores from historical stockpiles were processed through Barrick's Goldstrike pressure oxidation facility, thereby providing preg robbing feeds for a variety of metallurgical testwork. This paper describes the effects of amount, type, place and time of addition of activated carbons on CIL gold recovery and shows that native carbon in plant PDX'ed discharge solids can still preg rob gold loaded activated carbon.

Jan 1, 2011

By M. M. C Jiménez, D. C. Buzzi, D. C. R. Espinosa, J. A. S Ténorio, G. F. R Oliveira

In this work the extractive and selective capacities of solvent extraction synergistic systems to recover nickel and cobalt were evaluated. The liquor used was from the high pressure acid leaching process (HPAL). Initially the industrial liquor, processed from lateritic ores, was analyzed to identify the concentrations of the metals. Experiments of synergistic solvent extraction were performed later. The extraction liquid-liquid was carried out with a mixture of Cyanex 272 (CY) and Ionquest 290 (IQ) extractants. The process was executed with the temperature of 65 ºC, pH of 5.2 and the ratio aqueousorganic 2:1. Systems of 80% kerosene and CY 20%, CY 16% - IQ 4%, CY 12% - IQ 8%, CY 8% - IQ 16%, CY 4% - IQ 16%, IQ 20% were studied during 20 minutes. The results of this paper showed that the mixture of these two extractants doesn’t improve significantly the recovery of nickel and cobalt from liquor.

Jan 1, 2014

By D. Sharma, A. K. Singh, R. Singh, P. K. Mandal, M. Sarkar

"This paper deals with the stability investigations carried out at the XIVth seam of Jitpur colliery. The study was conducted to investigate the possible causes of roof cavity formation and face spalling at the middle slice face of block-3 longwall panel and to suggest remedial measures. The instrumentation and monitoring work was carried out in the panel over a period of nine months. On the basis of observations, it was found that if the maximum face span was reduced from the existing 4.8 m to 3.6 m, and if the face time schedule cycle was reduced from a maximum of 37 days to about 18 days, this problem could be eliminated. The recommendations of CMRI have been implemented in the middle slice face of block-4 panel with success. IntroductionModerate to steeply dipping, undisturbed seams of uniform thickness are worked by way of inclined slicing parallel to walls. In this method, the seams are treated as a combination of several moderately thick seams dipping parallel to roof and floor. Numerous variations of multislice mining have been used worldwide to get high coal recovery under local conditions of geology, subsidence control, proness to spontaneous combustion, statutes and economics. Multislice mining can proceed either downward descending from the roof or upward ascending from the floor. Ascending methods require backfill behind the working face to provide a base for the next slice. It is also adopted for surface protection against subsidence or mining under a massive roof. This paper presents a scientific study conducted in Jitpur colliery, IISCO where a 9 m thick seam is mined in three slices in ascending order with stowing."

Jan 1, 2002

By Zoltan Hajnal

Magnetic studies have been carried out on 88 surface and 157 underground samples from the Coronation Mine area of northern Saskatchewan. The intensity of the surface samples was compared to trace element determinations from the same locality. A good correlation was found between the titaniferous constituent of the rocks and the intensity of magnetization. From the direction of the remanent magnetism, two virtual geomagnetic poles were determined -latitude 12° 54' North, longitude 158" 17' West; and latitude 23" 42' North, longitude 163° 45' West. The sulphide ore specimens showed anisotropic susceptibility characteristics. A relationship was found between the measured maximum susceptibility values of the ore specimens and the direction of the tectonic forces which are considered to have formed the structure at the Coronation mine. Introduction T HIS paper summarizes the results of a study of the magnetic properties of samples from well-known Precambrian formations. The observed data give information for an interpretation of the magnetic field conditions in Precambrian times. The high magnetic intensity values indicate the importance of the study

Jan 1, 1965