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By T. A. Apelt, B. J. Elliot

"In September 1993, the flash furnace at Kalgoorlie Nickel Smelter, KNS, was brought off line after almost 12 years of operation. This is a record campaign life for a flash furnace. The furnace was' totally rebuilt and the capacity of the plant increased from 540 000 tpo to 750 000 tpa of concentrate throughput. The throughput increase was' achieved through the construction of a 525 t/day oxygen plant and upgrading of various plant ancillaries. A number of significant design modifications were also built into the flash furnace and oxygen enrichment was implemented in the operation of the Peirce-Smith converters.This paper discusses the rebuilding of the flash furnace and design modifications made to furnace equipment and ancillary plant. Some preliminary post-startup operating data are presented.IntroductionIn September 1993, Campaign 6 of the flash furnace was concluded and the furnace brought off line for rebuilding. The campaign length was almost 12 years and set a new record for campaign length. Planning for the rebuild took place over the last five years of the campaign. A number of modifications to the design of the furnace and the ancillary plant were planned to coincide with the furnace rebuild. The furnace was rebuilt and recommissioned in 70 days. The increased plant capacity of 750000 tpa has been achieved by the construction of a 525 t/day oxygen plant and modifications made to ancillary plant which centred around increased p~ control, efficiency and hygiene. This paper examines the development and implementation of the modifications made to the furnace and ancillary plant. Preliminary post-shutdown performance data are presented."

Jan 1, 1995

By Kai Bartram

The successful application of color sorting machines has established sensor-based sorting in the mineral industry in recent years and is considered today as a significant innovation in processing technology. However, we are only at the beginning of (market) introduction. New sensor systems have been developed, which exploit material properties such as electrical conductivity, magnetization, molecular structure, thermal conductivity etc. This opens up new exciting preconcentration and upgrading possibilities for many applications such as nickel, gold, copper and other ores as well as for industrial minerals, diamonds and other gem stones.

May 1, 2009

The successful application of color sorting machines has established sensor-based sorting in the mineral industry in recent years and is considered today as a significant innovation in processing technology. However, we are only at the beginning of (market) introduction. New sensor systems have been developed, which exploit material properties such as electrical conductivity, magnetization, molecular structure, thermal conductivity etc. This opens up new exciting pre-concentration and upgrading possibilities for many applications such as nickel, gold, copper and other ores as well as for industrial minerals, diamonds and other gem stones.

Oct 1, 2009

By Gene O. Cowie

"Zinc, which once enjoyed an unchallenged position in the field of decorative applications, has lost a substantial share of its markets to other materials, particularly plastics. This turn of events has led the zinc industry to explore new market areas, particularly those applications where the engineering properties of zinc can be utilized. This paper gives an overview of the zinc industry's efforts to develop the data base and product development technology which have enabled zinc alloys to emerge as engineering materials. It also indicates those areas in which the research facilities of the zinc industry must be employed to ensure that zinc alloys keep pace with developments in competitive materials and processes.The Materials RevolutionThe development and utilization of new materials and manufacturing processes progressed for centuries by evolution. Recently it erupted into a revolution, which may become as significant as the industrial revolution. The materials revolution has impacted upon many industries, but none has been affected more traumatically than the North American automotive industry. The plight of that industry is of great importance to us because their problems have, to a great degree, become problems to the zinc industry.Much of the impetus behind the automotive trauma came from the battery of motor vehicle regulations promulgated by the United States government in the 1970s. These regulations required that the efficiency of passenger cars, in terms of miles per gallon, be approximately doubled in ten years. In view of the fact that major changes in the automotive world require three years of lead time to implement, the industry was left with only seven years to perform the task. The automotive industry was simultaneously required to make progress in other areas, such as reduced emissions, reduced cost of repairs and increased levels of occupant safety. These added demands not only diverted some of the available resources away from efficiency goals, they often ran in direct conflict. For example, when you are required to provide a front bumper which will absorb the energy of a 5-mile -per-hour barrier collision, you must add both hardware and structure to the vehicle. This adds weight, and increased weight reduces miles per gallon."

Jan 1, 1983

By F. W. Wellmer

"I would like to comment on the classification scheme of ore reserves based on geestatistical and economic parameters as proposed by Wober and Morgan in the CIM Bulletin, January 1993.In principle, a classification system that combines quantitative data for levels of confidence and errors with economic expectations must be welcomed. I would like to point out, however, two aspects of the proposed classification system which might create ambiguities, and therefore problems, by working with two levels of confidence and two kinds of block sizes. A normal classification scheme reflects the information density, the highest reserve category such as class A, or proven, or measured reserves having the highest density. This is not necessarily the case in the scheme of Wober and Morgan (1993), unless the definitions are amended.I. Assuming, as the authors do, that the estimation errors show an approximately normal clistribution, at the 95% confidence level, the standard deviation has to be multiplied by about 2 for the error and, at the 84% confidence level by about 104. Reserves (or resources) with the same or even higher information density than class A reserves, which at the 95% confidence level would not fulfill the required economic criteria at the threshold level, i.e. not qualify as ""ore"" at all, could be retained ""on paper"" to class B reserves by just multiplying the standard deviation by the factor 104 instead of 2, thereby narrowing the error.This statistical ambiguity was partly inherent in the old German classification scheme which used varying confidence levels and errors (GDMB 1956; Jahns 1959). In the new German scheme, which was later adopted in Austria in a moclified version, the level of confidence was therefore fixed at 90070 for all reserve categories (Wellmer 1983; ONORM 1989)."

Jan 1, 1993

By R. Noriega, M. Suazo, V. Murariu

Current AG and SAG mill circuits have continued the trend to larger, fewer mills. These large mills place a significant additional load on the discharge systems and it has become imperative that the designs of these mill discharge systems are evaluated carefully to ensure maximum efficiency and have the capacity to be able to handle the increased mill discharge volumes. The current generation of multiphysics modeling tools allow a detailed analysis of AG and SAG mill discharge performance. The combination of Discrete Element Method modeling and Computational Fluid Dynamics allows the designer to model in detail all aspects of a mill discharge performance. This includes a detailed description of the build-up of solids and slurry in a mill discharge, the recycle of material back into the mill through the grates, the relative wear rates and the occurrence of overloading at the pinch points. These tools allow intelligent decisions to be made regarding the type of discharge arrangement, pan lifter geometry, and discharge cone design, so as to ensure that the discharge is capable of handling the duties required for a specific installation. This paper details the current state of the art in these modeling tools, and provides an overview of some recent applications.

Jan 1, 2012

By Rainer Süss

An investigation was carried out by Mintek to investigate the influence of a range of alloying additions (vanadium, cobalt, zirconium, antimony and germanium) on the formability and hardenability of alloys with gold content >90 wt%. This paper reports on the hardening mechanisms that can be utilised to increase the hardness of gold (>90 wt% Au) by conventional alloying, as well as the hardening effect obtained by alloying with specific elements. Preparation methods for the alloys are described, which include the steps of melting, annealing, quenching, cold working and age hardening. Focus is given specifically on alloys that were developed at Mintek with a gold content >90 wt%, which are not only harder, but exhibit good resistance to tarnishing and corrosion.

Oct 1, 2003

By Ros Taplin

Realizing the potential of cutting greenhouse gases (GHGs) associated with mining, a variety of approaches has been proposed for their mitigation. The Clean Development Mechanism (CDM) under the Kyoto Protocol to the UN Framework Convention on Climate Change (UNFCCC) has been a key mechanism to assist in implementation of mitigation measures. The objectives of CDM are not only to assist Annex I countries in meeting their GHG emissions reduction targets with cost-effective reduction but also to achieve sustainable development in non-Annex I countries. However, apart from China, India, Brazil and Mexico, many developing countries are still in the stages of formulation or realizing CDM strategies. Projects associated with methane capture and flaring are the fourth most prevalent type of CDM project internationally. This research primarily has addressed emissions abatement and sustainable development aims and effectiveness of registered CDM projects associated with coal mining in China. The paper reviews 30 currently registered CDM projects in China on the UNFCCC database and six other non- Chinese projects. Systematic evaluation involving content analysis of documentary evidence regarding coal mining CDM projects is presented in relation to firstly, quantitative reduction of GHG emissions and secondly, sustainable development outcomes. The projects have been assessed via a set sustainability criteria. Overall it was found that sustainable development goals are only briefly referred to in Project Design Documents, Letter of Approvals and validation documents. Varying types of sustainability initiatives have been implemented with weak to strong indications of effectiveness. This has implications for the future effectiveness of CDM projects in the mining sector, the proposed new market mechanism under UNFCCC, and for assessment of projects under mechanisms established outside the UNFCCC.

Aug 1, 2013

By Stephan Day

Comments on Robust M3 to Protect Water Quality ?Regulatory and philosophical thinking have tended to evolve at decade scale since 1970s. ?Mines typically last more than a decade. ?Robustness is defined by the ability to adapt to new realities. Managing Water Quality in BC ?1973 ?BC Pollution Control Objectives ?1977 ?Federal Metal Mine Liquid Effluent Regulation (Fisheries Act) ?Late 1980s ?Philosophy of ?Designing for Closure? ?1990s ?Designing for Acid Rock Drainage Management ?2000s ?Awareness of need for water quality management in general, regardless of acidity

May 1, 2010

By P. R. A. Andrews, R. K. Collings

"SUMMARYIn cooperation with the Ontario Ministry of Natural Resources, selected deposits of Potsdam sandstone in the Ottawa-Kingston area were core-drilled and evaluated by CANMET as potential glass and foundry sand. Analyses of cores ranged from 84.6 to 98.5% Si02, 0.09 to 0.65% Fe203' and 0.07 to 2.10% A12°3' The cores were largely composed of white to grey, relatively tough sandstone. Impurities included iron as pyrite, iron oxides and staining on the quartz grains; carbonates as calcite; and aluminum oxide as feldspar. Beneficiation included size reduction to grain size, about 600 um, by jaw, roll and cone crushers, and grinding in a muller-mixer. Removal of fines was achieved by attrition scrubbing and washing. Further removal of impurities was achieved by reverse flotation of pyrite, iron oxide, feldspar, and carbonate minerals employing both anionic and cationic collectors. Flotation resulted in a substantial improvement in the quality of most samples; analyses of quartz concentrates showed 98.5 to 99.7% Sial> 0.022 to 0.156% Fe203' and 0.07 to 0.62% A1203. Further reduction of the iron content by wet magnetic separation and acid leaching also was investigated. On the basis of the samples submitted, sands/ones from six of the seven deposits studied have potential as sources of glass sand. Foundry sand tests were inconclusive because of the small quantities available for study."

Jan 1, 1986

By N. Plint, M. Potgieter

The Anglo Platinum Mogalakwena North concentrator was one of the first three hard rock mineral processing applications to utilise a HPGR circuit in preference to a SAG milling circuit. This was driven by the extreme competence of the ore that had given rise to throughput issues on the original South Plant. Despite more than adequate capacity and performance of the individual comminution units, the circuit has struggled to obtain full design capacity. A thorough review of the integrated performance of the circuit revealed a wide range of bottlenecks and underutilised parts of the circuit arising from design issues. Interestingly, the major opportunities lie in materials handling issues and mismatch of loads about the circuit. This paper presents the high-level outcomes and the associated opportunities, and is pertinent to all HPGR circuit designs.

Jan 1, 2012

By Jorgen Elbrond, Noel Billette

"La connaissance du niveau de variation de I' alimentation d' une usine minéralurgique est essentielle pour estimer le taux de récupération dans un concentrateur. De plus, il est important de connaître la période moyen ne de correlation afin d’améliorer la qualité des contrôles et de l' au tornatisation.Le modèle proposé permet de prédire ces paramètres à partir du minerai en place et des activités d'exploitation dans une opération à ciel ouvert. II est basé sur la combinaison des variogrammes directionnels dans diverses zones d'un gisement, ce qui permet de définir la correlation à la sortie de chaquc zone en fonction des decisions opérationnelles, puis sur une loi binômiale modifiée, afin de séparer minerai et stériles dans Ie but de décrire variance et corrélation dans Ie minerai même, Les statistiques classiques sont alors utilisées pour décrire la combinaison de plusieurs zones et obtenir la variance et la correlation au concentrateur.IntroductionUn concentrateur est habituellement rodé de facon à recevoir une alimentation à teneur fixe en métal ; Ie minerai qui s'y presente a, par contre, tendance à osciller auteur de cette valeur cible, tantôt plus riche , tantôt plus pauvre . Ces variations entraînent des pertes de deux types: tout d'abord, la teneur du concentré oscille de facon similaire à celle de l' alimentation , ce qui peut même impliquer des pénalties a I'usine de smeltage lorsqu'elle est trop riche ou trop pauvre; la récupération peut pour sa part être diminuée de plusieurs points par un engorgement du circuit lorsque la teneur est trop forte."

Jan 1, 1984

By G. W. Davies

"IntroductionThe development of British Columbia's northeast coal deposits, represents the single biggest industrial undertaking in British Columbia's history.As a result of this development, several thousand jobs were created, hundreds of millions of dollars in new tax revenue and billions of dollars in new foreign exchange began flowing into Canada.The Northeast Coal Development began in 1981 with the signing of sales contracts to ship a total of 6.5 million tonnes of metallurgical and additional quantities of thermal coal annually to Japan over a 15-year period. The current long-term agreements contain provisions for extension to 20 years.The sales contracts with a group of Japanese steel mills were signed by two Vancouver-based mining companies, Quintette Coal Limited and Teck Corporation. The agreements followed years of exploration and negotiation beginning in 1968.The first shipment of coal from Quintette and Teck's Bullrnoose Mine was transported by BC Rail and Canadian National Railways to the Ridley Island coal port in the fall of 1983."

Jan 1, 1992

By T. R. Heflin

The paper provides a comprehensive discussion of pump selection for the hydrometallurgical industry. Material suitability, in addition to proper size and design, will provide extended life for pumps in erosion /corrosion service.

Jan 1, 1979

By Ian Rozier

"Emphasis in recent years in western Canada has been placed on the development of large open-pit coal mines, the most notable developments being in northeast British Columbia. However, vast resources exist below the limit of economic open-pit mining, and with world demand predictions of the late seventies in mind, the potential of underground coal mining in western Canada has been investigated. Particular emphasis has been placed on the Plains coalfield of Alberta, and there is optimism that underground coal mines will be developed in the Lethbridge area of southern Alberta.With no existing operations in southern Alberta with which to compare mining conditions, any mine planning and feasibility level studies rely heavily on the engineering/geotechnical data obtained from surface investigation to predict ground control problems and technical constraints on mining. Such investigations have been integrated with exploration drilling programs. Emphasis has been placed on extracting maximum information to provide an over-all appreciation of potential ground conditions and to identify specific ground control problems that could be encountered.The acquired geotechnical parameters are then used to evaluate the mine properties from an engineering standpoint for input into the determination of optimum mine layouts, development directions, mining methods and roadway and face support requirements. These geotechnical studies have been primarily directed toward the longwall mining method, but the acquired data base could equally be applied to alternative mining methods.In addition to the lithologic and structural controls which relate to roof stability, caving characteristics, floor heave and subsidence, investigations have been directed at gaining an understanding of the over-all surface and ground water regime with respect to potential inflow into the mine openings and ground control problems that could be caused by inflows encountered during mining. Experience has shown that soft floor conditions and water control are important factors to be considered in a longwall layout, and without doubt these parameters will play a major role in the design and operation of a successful longwall operation in the Lethbridge coalfield."

Jan 1, 1986

By T. H. North, A. G. Glover, R. J. Pick

"Girth welding operations represent the rate-limiting step in pipeline construction. A joint industry-university program was set up to establish the field welding characteristics of large-diameter, high-strength line pipe.Theoretical work carried out at the University of Waterloo showed that pipe wall thickness and joint misalignment prior to welding has a marked influence on the lifting stresses acting on the root pass of girth welds. Pipe diameter and pipe ovality had negligible effects. Super-position of lifting and residual stress (caused by the fusion welding operation) highlighted regions of the weld bead most susceptible to hydrogen-induced cracking.The field welding characteristics of 1219-mm-diameter, 13.72-mm-wt Grade 483 line pipe were evaluated using a specially designed test rig. The principal test variables were lift height, delay time after root pass deposition, preheat temperature, pipe composition and joint misalignment prior to welding. For any given life, preheat and joint misalignment prior to welding had the most significant effect on cracking tendency.The output of this program has industrial significance and illustrates the beneficial features of university-industry collaboration.IntroductionField welding operations comprise the rate-limiting step during pipeline construction. Crack-free girth welds must be made in a wide range of weather conditions and consequently the field weldability of line pipe compositions directly affects pipeline integrity and construction economics.Pipe-laying practice comprises root bead deposition followed by a skidding operation involving lifting (or lowering) the pipe length onto skid s so that the next pipe length can be aligned prior to welding. Consider pipeline construction using 24.4-m lengths of 1219-mm-diameter , 13.72-mm-wt Grade 483 pipe weighing approximately 10,000 kg. Skidding involves loading a 3-mm-thick root bead by moving the free end of the pipe through vertical distances of up to 700 mm . The likelihood of cracking in these circumstances depends on the inherent crack susceptibility of the pipe composition employed, on the hydrogen content of the deposited weld metal and on how well the joint handles the external stressing caused byskidding."

Jan 1, 1981

By Y. Qi

A cell-level nonlinear dynamic model of solid oxide fuel cell (SOFC) based on physical diffusion principles is built in this note. It demonstrates that reactant diffusion processes from gas flow bulks to triple phase boundaries (tpbs) play an important role in the dynamic behaviors of SOFC. The simulation shows that under certain condition, the effect of the double layer capacitance may be neglected. The phenomenon of slow rise of voltage in current interrupt experiment may be explained by the dynamic behaviors of partial pressures in the vicinity immediately above tpbs.

Jan 1, 2005

By Z. Pilecki

This work concerns the identification of weak zones in the structure of a rock mass endangered by outburst of gases and rocks in the Rudna copper ore mine at greater depths (approximately 1200 m). A special methodology has been undertaken for the recognition of that threat in the wake of an outburst in the mine in 2009. No similar phenomena have been previously recorded in KGHM Polska Miedz copper ore mines. The research described in this paper was carried out in the new part of the deposit prepared for mining. Geophysical methods were used: seismic tomography and borehole ground penetrating radar (BGPR), along with particular identifications using geological engineering methods. In the researched area, Permian layers of sandstone and shale clay (Weissliegendes formation) and of Zechstein dolomite (top of Rotliegend formation) and anhydrite occur in the copper ore deposit. The rock layers are characterized by variable thickness and intensity of mineralization, varying internal structure, and local fracturing containing different gases and water. It is assumed that accumulation of gases occurs in the tectonically fractured dolomite. The study was focused on the recognition of the structure and properties of the dolomite layer lying directly within the roof of excavations. The first tests were performed with seismic tomography for the recognition of anomalous changes in the elastic properties of the rock mass. The results of these studies were used to design a control borehole for a detailed geological engineering assessment and BGPR surveys with 100MHz antennas. Seismic tomography enabled the identification of changes in Pwave and S-wave velocity, the Vp/Vs ratio, dynamic Poisson's ratio and dynamic Young's modulus. It was clear that seismic anomalies required verification by other methods. The BGPR survey was performed in a specially designed borehole, passing through the selected seismic anomalies. While the borehole was being drilled, the outflow of gases was identified, with varying amounts of CH4, CO2, and H2S detected, as well as water outflow. The results of BGPR confirmed the location of a reservoir of water and gases, about 30 m in length, found in layer of dolomite. The direct cause of the BGPR anomaly was assumed to be intensive fracturing, a greater content of clay material in the dolomite, and the presence of water in the fractured zone. The BGPR image was correlated with information on lithology, fracturing based on the RQD index and additional information acquired during drilling about water and gases surveys and other symptoms. The achieved results also showed a very strong correlation between the location of the zone containing gases and water and the anomalous S-wave velocity and field of dynamic Poisson?s ratio, and to a lesser extent other seismic parameters. It was found that the other measured seismic anomalies may be of the same nature as those identified in the control borehole and accordingly will require the implementation of detailed identification. The performed tests have also shown the usefulness of geophysical methods to identify geodynamic hazards under the geological and mining conditions of the copper ore deposit in the Rudna mine.

Aug 1, 2013

By D. G. Ingram

This paper reviews the operating and maintenance practices at Bethlehem Copper from the commencement of operations in November 1962 to the present. Cost data and wear life of major components are also discussed.

Jan 1, 1979

By X. Zhong

Thermal shock resistant properties of reaction sintered bauxite-based ß -Sialon bonded corundum have been investigated, and the results are compared with those of Al2O3 based counterpart. It is found they all have very good thermal shock resistance. Their residual strength ratios after one thermal shock cycle at ? T=1200°C and A T=1350°C are 61-73% and 53-65% respectively. TSR parameters are calculated based on thermal expansion, modulus of elasticity, and fracture toughness determined. The reasons for improved TSR of these composite materials are discussed.

Jan 1, 2004