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By J. E. Dutrizac

Canada is currently the world's largest supplier of zinc concentrates and is also a major producer of zinc metal. This dominant position in the world's zinc market is a fairly recent circumstance and, in fact, the country's zinc industry was founded only in the early part of the twentieth century. By contrast, the American zinc industry was well established by the mid-nineteenth century, largely based on technology originally imported from the still older European practice. Initial attempts to create a viable Canadian zinc smelter were based on the traditional practice and were unsuccessful; success came only with new electrolytic technology, much of which was developed domestically. The purpose of this paper is to outline the early attempts to produce metallic zinc in Canada and to trace the gradual development of these first efforts into a viable zinc industry based on modern science and technology.

Jan 1, 1999

By D. L. Griffith

THE realization by metallurgists of the important effect that traces of impurity may have upon the properties of a metal, and their steady demand for purer and still purer metals, have made the special cools for 'trace' analysis of increasing value. In the United States at least, spectrographic analysis is becoming the standard method for determining the impurities in zinc die-casting alloys. The Hudson Bay Mining and Smelting Company, as a producer of virtually pure zinc, uses the spectrograph to control the purity of its products, and-as the electrolytic method is employed here-to control both the impurities in the electrolyte and those 'trace' elements, which, while they do not contaminate the zinc, have a great effect on the plating efficiency. The general plan of the laboratory is shown in Figure l; the housing for air purification, which is on the roof, is indicated by broken lines. One of the chief factors affecting the layout was the easy way in which a spectrographic assay can be spoiled by contamination. To minimize the quantity of dust tracked in, the laboratory was made separate from the general research laboratories, and an office was placed between the two. This arrangement has its drawback because of the traffic through the office, but it has effectively cut down dust. For similar reasons, the available space was subdivided into a number of small rooms, and the air currents in the laboratory were so arranged that dust would be carried where it would do least harm. Air is drawn in at the roof over a 50-kilowatt bank of Calrod heaters, through Annis air filters, by a No. 4 Sirocco fan. Most of it is forced into the spectrograph room, but some goes to the office and darkroom. The air flow is from the spectrograph room, through the plate-measuring room, into the chemical laboratory, where it is exhausted by a No. 1% Sirocco fan on the fume hood. Air can also re-circulate from the plate-measuring room back to the heater. The arrangement is such that the air in the laboratory is maintained at higher pressure than the outside air; consequently, no dirt enters through cracks about the windows and doors. A thermo-regulator holds the temperature constant within one or two degrees; only on the hottest days in summer does the temperature rise enough to affect the focus of the instrument.

Jan 1, 1940

By J. Keith Haddock

"Introduction The Coal Valley Mine is operated by Luscar Stereo (1977) Ltd. with the Alberta Energy Company having a minority interest. The mine produces 2.0 million tonnes of bituminous thermal coal per year. Deliveries include 1.5 million tonnes to Ontario Hydro and 0.5 million tonnes to the export market via bulk handling facilities on the west coast near Vancouver, B.C. There are a number of mining methods utilized at the mine including open-pit by truck and shovel, strip mining with large draglines and stripping with scrapers. The mine is located 100 km south of Edson, Alberta. Geology The coal measures are concentrated within a 210-metre int~rval of the Paleocene section. The coal seams were originally named by the mining companies in the earliest days of development of the area and these names continue to be used today. Of the five main seams, only three are presently economic to mine based on quality, thickness and depth of cover. These are the Val d'Or, Upper Silkstone and Mynheer. The Coal Valley Mine is located in the structurally deformed foothills area of Alberta and the structure of each mining area is therefore very complex. The general bedding strike is 305 degrees azimuth but major thrust faulting and folding has extensively deformed the natural seams as a closer examination will show. The Mynheer Seam, located at the base of the coal measures, ranges in thickness from 5 m to 10 m and has numerous bentonite and shale partings. Because of inherent geological features, the Mynheer Seam has been subdivided into two zones, the Mynheer 'A' and the Mynheer 'B', and the mining of coal in these zones has necessitated the utilization of distinctly different mining methods. The structural regime of the Mynheer 'A' zone consists of an overturned asymmetrical anticline crest containing a steeply dipping major thrust fault which has raised the seam above the present topographic level. Further extensive shearing and rotation of the coal has resulted in the coal taking a 'pod' shape. The Mynheer 'B' Zone is a continuation to the southeast along strike from the Mynheer 'A' Zone. The bedding dips to the southwest at an average of 12 degrees and is interrupted at the south end by a transverse fault and to the north by its outcrop at the surface."

Jan 1, 1985

By M. Greyling, C. Panaou, M. Bellino

Commonly the most frequent method of calculating the overall mass balance of a multi mineral platinum-group metal (PGM) concentrator circuit in Southern Africa has been through the use of spreadsheets, typically Microsoft EXCEL®. While there are some advantages in using spreadsheet based mass balances during the conceptual design phase of the project, their use becomes limited in the detailed design phase of the project. This paper discusses the successful application of METSIM® for mass balancing of a PGM concentrator and highlights the benefits gained during the conceptual and design phase of the project.

Jan 1, 2005

By Norman B. Davis

Introductory Feldspar is one of the most important mineral products consumed by the various branches of the ceramic industry. In the manufacture of table ware, electric porcelain, floor tile, and enamels, it supplies the chief fluxing ingredients necessary to bond the other more or less inert materials together when moulded into desired shape and fired in a kiln. Feldspar is used in the manufacture of bottle glass as a means of introducing alumina in a form easily assimilated. It is also used in certain scouring soaps particularly designed for cleaning enamel and glass surfaces. Feldspar, as it finds its way to the trade, is not a single mineral but is rather a mixture of various proportions of the feldspar silicate series, either in natural intergrowth or blended in the milling process, to produce a desired result. It is often further modified by the presence of quartz in amounts up to 30 per cent. The table on the next page gives typical commercial analyses of feldspar from various sources. Canadian feldspar produced to date has consisted mainly of the high-potash, relatively low-soda, variety, and has enjoyed a good market in the United States for the manufacture of enamels, electric porcelain, and vitrified table-ware. About eighty per cent of the output has been exported to the United States, but, with increased milling facilities in Canada and changes taking place in domestic United States sources of supply, the proportion exported will be reduced next year.

Jan 1, 1931

By Charles Goodeve

"BEFORE I begin, I should like to thank The Canadian Institute of Mining and Metallurgy for the honour they have bestowed in inviting me to give this address at the fourth annual C.I.M. Conference of Metallurgists banquet.Secondly, I should like' to convey the greetings of the Iron and Steel Institute of Great Britain in accordance with a request made by its Council at its last meeting. The I.S.I. hopes for the continued growth in strength of this annual Conference and in the collaboration between our respective societies.When I read the program of this Conference, it was brought home to me what a non-ferrons country Canada is. Also, I realized what enormous advances have been, and are being made, and what an ex-citing field non-ferrous metallurgy is for the scientist. This made me wonder, as I have done before, whether the future for steel was proof against these advances.At present, iron and steel stand astride the metallurgical world like a Colossus; I hope that the bronze industry will pardon my stealing their thunder and mixing my metaphors! Will this still be so in the future?The best way to answer this question is to take a look at the fundamentals to see why the iron atom dominates to such an extent that al! other metals are called ""non-ferrons."" Is its present position due to historical and therefore ephemeral reasons, or is there a fundamental difference between the atom of iron and those of other metals?"

Jan 1, 1966

By L. St-Georges

In aerospace and transportation industries, severe problems are related to fatigue failure. Aluminium is frequently used in these industries to optimize the solidity and minimise the weight of the structures. Nevertheless, the fatigue life of aluminium alloys is limited and specific efforts have to be made to reduce the vibratory stresses in the mechanical parts. When riveted, the life of the sheet metal structures can be increased compared to welded structures, due to the energy dissipated by the friction between the rivets and the sheet metal and the sheets themselves. In the past decade, a new tool was developed to assemble aluminium structures; the friction stir welding. With this new technique, fatigue life of the aluminium welded joints can be increased by a factor from two to ten. However, less energy can be damped by the friction between the components and increased vibratory stresses may occur. In this investigation, the potential of the friction stir welding to create damped aluminium sheet metal structures is evaluated.

Jan 1, 2006

By Claudio Rocha Rosales

"Peñoles is a mining group with integrated operations in the smelting and refining of non-ferrous metals, and is also a chemicals producer. Peñoles is the world’s foremost producer of refined silver, metallic bismuth and sodium sulphate and is the leading Latin American producer of refined gold, lead and zinc. The Met-Mex Peñoles Zinc Plant commenced operations in 1973 with an annual production capacity of 105,000 t/y. Year after year the production has been increased, and at present, the production capacity is 240,000 t/y. In this paper, the leaching process,particularly the operation of the jarosite circuit is reviewed ,specifying process improvements to treat high iron calcines.INTRODUCTIONThe purpose of the leaching process is to recover the metals, mainly zinc,through a series of extraction stages with sulphuric acid solutions, which progressively increase the zinc recovery. After the series of acidification stages,the solution, which is rich in iron, is sent to the jarosite circuit to separate the zinc from the iron (Garcia & Valdez, 1996).The first step of the leaching process is the neutral leach circuit which produces a zinc sulphate solution that is sent to the purification section for the removal of impurities such as cadmium, cobalt and copper, after this solution is sent to the tankhouse to feed the electrolytic cells."

Jan 1, 2016

By J. E. Hawley

"The zinc-lead deposit of the Lake Geneva Mining Company is on lot 7, con. VI, Hess township, Sudbury district, Ontario, about 10 miles northwest of the northern rim of the Sudbury Basin. Though a relatively small deposit, it shows some rather interesting relations to cross-cutting, pre-ore, quartz diabase dykes, which merit description.The deposit was discovered in October 1924 by J. H. Collins beneath iron-stained drift and oxidized sulphides. This proved to be the northwestern extremity of the orebody, the remainder of which extends southeast below swampy ground. Exploration began in 1927. In 1928 a vertical shaft was sunk to 250 feet and a level established at 235 feet. Later the shaft was deepened to 400 feet and new levels opened at 315 and 375 feet. In 1943 an inclined winze was sunk below the vein from the 315-foot level to a vertical depth of 640 feet, and two additional levels were opened at 525 and 615 feet respectively.The geology of the area has been described by T. T. Quirke (1), F. F. Osborne (2), F. J. Alcock (3), and Ralph Tuck (4). Private reports have also been made by Carl Tolman, J. E. Gill, and K. W. Fritzsche. Tuck's paper, covering the work completed to 1930, gives a detailed account of the character of the ore and enclosing rocks.Up to May 1944, when the property was closed, all ore above the 375-foot level and a small tonnage from below this elevation had been removed. Ore mined from 1941 to 1944 yielded the following:"

Jan 1, 1954

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 A. V. Lyamin, J. P. Wang, A. J. Li, Z. Qian

"For general stability analysis of rock slopes, rock mass strength and rock mass disturbance are definitely should be considered. In addition, the impact of earthquakes must be taken into account. In fact, the rock mass strength is very difficult to be assessed which causes the difficulty of analysing rock slope stability. Therefore, an empirical failure criterion, the Hoek-Brown failure criterion, has been proposed. It is one of the most widely accepted approaches to estimate rock mass strength. The rock mass disturbance is important and was found having significant influence on evaluating rock slope stability, especially for rock slope with poor quality rock mass. In the Hoek-Brown failure criterion, the disturbance factor can represent the level of the rock mass disturbance which would provide a reasonable basis for estimating rock mass strength.This research will not only discuss the slope factor of safety, but also consider the influence of the seismic force on rock slope stability assessment using pseudo-static method. In practice, only horizontal seismic coefficient is used. Various magnitudes of the disturbance factor and recommended blasting damage zone thickness are also taken into account. The blasting damage zone thickness considered ranges from 0.5 to 2.5 times of slope height. The research results have potential to be extended and then sets of comprehensive stability charts can be provided for the rock slope stability evaluations. They will be convenient tools for practising engineers. In this study, finite element upper bound and lower bound limit analysis methods are employed. Their applicability has been investigated in some previous studies. The differences between upper bound and lower bound solutions are less than ±10% which would provide reasonable and acceptable range for rock slope stability safety factor estimation."

Jan 1, 2015

By T. Sakai

Present authors have succeeded in single pass large draught rolling of AZ31 and ZK60A magnesium alloy sheets below 200 °C without heating rolls by raising rolling speed above 1000 m/min. Heavy reduction larger than 60% can be applied by single pass high speed rolling even at room temperature. The rolled sheets showed fine recrystallized microstructure by dynamic recrystallization. The improvement of workability at lower rolling temperature is due to temperature rise by plastic working. In high speed rolling, almost all of the work done by plastic deformation is converted into the heat that raises the temperature of the sheet during rolling because the heat did not flow out of the sheet by conduction and radiation within very short time.

Jan 1, 2006

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 I. E. Puddington, F. W. Meadus

The beneficiation of barite in mill tailings using an agglomeration technique has been demonstrated. Barite was selectively absorbed from a conditioned aqueous slurry into a collector oil by mechanically mixing slurry and oil. The resulting oil-bonded barite-containing agglomerate was washed, to remove gangue material, and further mechanically contacted with dilute H2SO4 This treatment resulted in the transfer of barite into the aqueous phase. Grades as high as '97% BaSO4, with recoveries of 80%, have been obtained using this technique.

Jan 1, 1973

By G. Frithum

In the present paper a new and highly economic route for Fe-separation from HCl leaching processes in hydrometallurgical applications is described. In most ore leaching processes, Fe is involved and needs to be separated; HCl has become an interesting leaching agent, because it can be recycled. Usually a mix of Fe2+ and Fe3+ is obtained which can be hydrolyzed directly (in case only Fe3+) or roasted via pyrohydrolysis (in case of Fe2+) to ferric oxide. Economic oxidation of Fe2+ to Fe3+ is described, and potential technologies for regeneration of HCl with separation of Fe are shown and compared.

Jan 1, 2014

By W. G. Stevenson

With the author's background of extensive experience, this paper delineates the role of the prospector in modern-day exploration programs. The stages in the development of a prospect to a producing mineral district are outlined, and examples are given from the Ross River area of the Yukon Territory and the Peachland and Highland Valley areas of British Columbia.

Jan 1, 1970

By Per Hedvall, Jan-Eric Ståhl

"The main objective of this study is to introduce the new Sandvik’s production cost-model within Crushing & Screening (C&S) technology. So far, there have been different ways of determining different production costs in the industry, however, the previously published and presented methods have not been very efficient in calculating the costs per product and metric ton. Accordingly, the current study has been planned and started in collaboration with Lund University to provide an accurate and easy to implement cost estimation program to determine the costs for crushing and screening plants worldwide.The proposed model has been adapted to fit the C&S processes of different rocks/ores fractions. The result is presented as cost per ton of the end product(s).Within this paper the cost estimation results for 3 different crushing and screening plants are presented based on the information obtained from the following sources: a) documents at Sandvik SRP, b) Sandvik’s crushing & screening internal/external machines/plants data and information, c) literature studies, including the use of Sandvik’s internal/external simulation and software programs, d), visiting the crushing and screening plants ,e) interviews, information systems’ data, and, f) testing and observations by ourselves.In order to improve the level of accuracy and the validity of the attained results, simplistic Monte-Carlo simulations have been used, where needed. The achieved results, so far, have proven the reliability of the model. The calculated cost estimations have shown an accuracy over 80% when they compared with real cost data obtained from plant practices.The current cost calculation model, will offer the possibility of:•,Calculating the production costs in proposed and/or existing C&S plant.•,Making detailed cost analyses for the end product(s) in proposed and/or existing C&S plants.•,Determining the profitability of each finished product when it’s required.•,Cost optimization by potentially cutting the cost for part of C&S plant with an existing plant practice"

Jan 1, 2016

By N. Valkanov

This paper presents results of an investigation into the connection between minerals liberation management and flotation, responding to lead-zinc concentrator ?Erma reka?, in Bulgaria. Monitoring of a Zn flotation circuit was carried out. The causes for the high silica content in the final Zn concentrate were established. Quartz is present mainly as liberated particles (> 60?80 %) in the fine fractions of the products; therefore the selectivity of the flotation process is not effective. Two approaches were tested to reduce the quartz content of Zn concentrate: froth washing in Zn cleaner flotation and new gangue depressants in the Zn circuit. Experimental results from bench-scale flotation and industrial tests show that it is possibile to reduce the silica content of final Zn concentrate more than 2 times without the need for extensive regrinding. The depression of liberated quartz particles on all operations of Zn circuit using stage depressant addition is the right solution to produce high-grade Zn concentrate that meets the metallurgical requirements.

Aug 1, 2013

By N. M. Stubina, P. J. Lind

Barrick Gold is in the process of building several new mines and implementing new processes at existing mines for which metallurgical technology is of key importance. The roles of the company's Strategic Technology Solutions team and the Barrick Technology Centre are discussed within the context of their responsibilities within Barrick's Operations Support group. The paper will present an overview of the development of the technology centre from the former Placer Dome Research Centre to its current form supporting strategic technology, capital projects, and operating sites. Novel approaches to research and development will be presented as well as an overview of some of the technologies developed from bench-scale to pilot-scale, and beyond.

Jan 1, 2011

By X. L. Song, G. W. Zhang, F. Y. He, X. Xiao, L. L. Huang

This paper presents the design of a model and process simulation of a vertical mill based on a population balance model. The simulator, Simulink, which is a systematic modeling tool within MATLAB, was used for the simulation. The model will simulate the real time variation trend of each size fraction in the feed material to the vertical mill, as well as, the size distribution of the batch grinding products. Breakage distribution and selection functions are calculated based on batch grinding laboratory experiments using Back-calculation method. The simulated size distributions correspond with those in the actual mill operation having a relative error of less than 0.50%. This work lays the foundation for future research on modelling and simulation of a closed circuit grinding operation consisting of a vertical mill with hydrocyclone classifier.

Jan 1, 2016