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By K. Blower

"Since there was no representative from Wesfrob Mines Limited, the information on their infra-red concentrate drying operation, which had been prepared by Mr. K. Blower, was presented by Mr, Dorland. Mr. Blower, in submitting the information, emphasized that their objectives in this operation were (a) to guarantee less than 90%, of flow-moisture in their copper concentrates and thus satisfy marine shipping regulation• and (b) to minimize capital costs, The infra-red dryers have satisfied these objectives.To control final moisture in the copper concentrate, current practice is to preheat the filter cake with steam in the disc filter hood and then conveyor-0r7 the concentrate with infra-red calrod heaters. The application of steam aids the system as follows:1) Improves vacuum pump efficiency.2) Lowers viscosity of filtrate (increased temperature},3) Preheats the cake prior to radiant heating. (150°F)The hot cake discharging from the filter ranges from 10.6 to 10.9% moisture. After radiant heating the moisture level is reduced to 8.5% - 9.7% depending on production rate. Further moisture loss occurs during conveying and transferring to the stockpile for a final shipment moisture ranging from 8.1% to 9.5%. Production rate is frail J to 5 dry short tons per hour.1) #23 Conveyor 18"" flat belt covered from filter discharge to transfer point with 7 heaters end-to-end. Drive - Reeves Vari-Speed, 31:4 ratio, type 332-10-18, class ""D"", driving through a 24:1 ratio Dodge reducer. Speed of Conveyor - 3,9 feet per minute to 19.6 feet per minute. (Speed has been established and is not changed as a rule from the present level of a1:out 15.)2) #23 Conveyor 24"" wide, 20° troughed belt covered with 21 heaters, end-to-end from loading point, Speed - Constant at 54,2 feet per minute."

Jan 1, 1972

By A. A. Sizikov, V. A. Sizikova

Key parameters to consider for any producer: bring down production cost and lead time; Lean production as a tool to achieve maximum efficiency; How to implement lean principles: discontinuous vs. continuous production (aluminum industry); About RUSAL: global top-three aluminum producer; Lean tools at use at RUSAL's production facilities; Pull system, Standardization of work, Just in time, Continuous improvement, Customer-Supplier relations, etc.

Jan 1, 2006

By G. E. Rowan

"DURING the dark ages, the cherished dream of chemists was to find a process for converting base metal into gold. Many a wealthy-but-gullible patron lost a fortune in the search. Men who work with metals today are a bit more realistic. I haven't heard of a metallurgist who expects to develop any one alloy that will resist all corrosive media. In the field of stain-less steels, there are about forty different types of alloys that are used where corrosion is a •problem.A stainless product is ordinarily selected because it offers one or more of the following qualities:(1) Resistance to corrosion (2) Resistance to oxidation at high temperatures (3) Good mechanical properties at room temperature (4) Good mechanical properties at high or low temperature (5) Attractive appearance (6) Ease of maintenanceToday we are interested in discussing the stainless steel family of alloys because of their .ability to resist corrosion. We• will not try to explain the Theory of Corrosion. Let us assume that, when surface potential and oxide formations are properly controlled, iron will resist attack in various chemi.cal solutions. The addition of alloying elements to iron does this for stainless steels. The principal stainless alloys used by various Canadian industries are listed in the accompanying Table."

Jan 1, 1959

By Brennan Lang

Why Seal Tunnels? ?Restore groundwater levels to pre-mining conditions. ?Saturate rock mass to reduce acid rock drainage. ?Reduce discharge flow to the environment. ?Reduce or regulate flows to a water treatment plant.

May 1, 2002

By T. R. Stanley

Introduction The purpose of this paper is to interest mining men in the economic possibilities of sand deposits suitable for modern foundry work. Many members of the profession are constantly travelling over the country and it is felt that some knowledge of the necessary properties of foundry sands will enable these men t0 recognize such deposits. It is the experience of the writer that good sands suitable for the varied work of a foundry, such as that of the Consolidated Mining and Smelting Company, at Trail, are almost impossible to obtain from western Canadian sources. It is hoped that the following discussion may arouse some interest in the search for such sands. Sands are used in foundries for two purposes. The main use is for making moulds suitable for receiving hot metal. The mould must retain the? required shape until the metal has solidified. The second use of sand in the foundry is as an abrasive in sand blasting. This is a relatively minor use, and consequently will not be dealt with in detail. Any coarse sand with a high content of quartz will serve this purpose, but round-grained sands are superior to angular types, because they have not the same tendency to shatter on impact with the casting. Sand plays an extremely important part in the successful production of sound castings. This is more evident today than ever before, due to the greater variety of castings and alloys, each of which requires special sand characteristics. Poor sand is responsible for a great many foundry troubles which formerly were attributed to bad? metal; in fact, one investigator goes so far as to say that ninety per cent of bad castings can be traced directly to the sand. Very little of the vast amount of sand distributed over the earth's surface is suitable for moulding. It is the purpose of this paper to describe briefly the properties which are essential in good moulding sand. Sand for this work must be able to withstand the wash and hydrostatic pressure of molten metal, and yet be sufficiently porous to allow the gases generated in the mould to escape.

Jan 1, 1935

By R. Laucournet, E. Billy, M. Joulié

Today Li-ion batteries are considered as one of the most attractive available energy storage solutions. However in order to overcome environmental, legislative and economic issues, the management of used batteries has to be considered and mainly the recycling. The present paper deals with the recycling of used Li-ion batteries and the recovery of high value metals from active materials of electrodes. Lithium nickel cobalt aluminum oxide (NCA) and lithium manganese nickel magnesium oxide (LMNM) cathodes, which contain most of valuable elements typically used in the composition of active materials for Li-ion batteries are investigated by a hydrometallurgy route. The process is divided into two steps: the materials leaching and the elements recovery by a selective chemical separation. Some experimental parameters (acid nature, concentration, time and temperature) are studied to determine the most efficient conditions of dissolution. Then, the valuable elements such as nickel, cobalt and manganese are selectively recovered with a high efficiency close to 100 % and with a high purity by precipitation. By this study, an adaptable hydrometallurgy process can be defined according to the composition of Li-ion batteries to recycle.

Jan 1, 2014

By A. G. Matyas, B. Wasmund, R. C. Francki, K. M. Donaldson

"The construction of large. high-power electric furnaces has been an important factor in the growth of electric smelting technology . New developments in the design and operation of electric furnaces have been spurred by the escalating cost of electric power and increasingly stringent environmental constraints. Key areasofprogress include the application of high voltage to enhance furnace productivity; the installation of novel furnace cooling elements and robust binding systems to extend furnace life; development of process schemes to reduce power consumption by preheating and prereduction of the charge; and environmental control improvements for handling fine dusty feedstocks, and for furnace sealing.This paper reviews these developments and outlines a systematic approach for their application in the custom design of new or retrofit electric furnace facilities.IntroductionThe use of electric smelting furnaces has continued to progress during the last decade. Electric furnaces offer high throughput capacity and productivity. In addition, they produce minimum environmental impact, as the furnaces can be readily sealed, and only a small quantity of off-gas is generated. Electric furnaces present the most favourable choice of smelting technology where high process temperatures in excess of about l400°C are required.Their application is burdened by the escalating cost of electric power, hence it is important to seek new opportunities through further technological development. This paper reviews recent developments in the design and operation of high-power electric smelting furnaces, in the following areas:"

Jan 1, 1993

By Akira Fujisaki

"The oil crisis accelerated the change of non-ferrous metals' demand structure. Maturing societies in developed countries and preference for lighter, thinner and smaller products are eroding the non-ferrous metal industries' growth potential. Inventory-control, stockpiling and developing new demand are measures Japanese smelters have taken to cope with the changing demand.The most effective means for risk management of product demand lies in the cooperation between ore producing countries and metal consuming developed countries to assist developing countries in their efforts to ""take-off"", which in turn will bring about a surge of demand for metals.SummaryThe non-ferrous metal industry in the world is suffering its most serious slump since the war. With some of the markets of the advanced industrialized countries approaching saturation point and economized usage of natural resources and substitution growing, the possibility of a quick recovery of the demand for base metals is dim.To cope with the changing product demand Japanese producers have had recourse to such measures as strict inventory control and stockpiling for the purpose of stabilized imports. They have also tried hard for securing raw materials and promoting new field s of demand but the very core of ""risk management"" has been the diversification of line s of business to bolster and stabilize the foundation of management of the non-ferrous metal industry in Japan.To see the demand for nori-ferrous metals recover from the slump and be put on a path of solid development, we have to wait for the economies of the developing countries to ""take off"" and for its realization the economies of the developed countries must be reactivated with new growth industries playing a leading role, and the transfer of technology and money recycling must be carried out smoothly under an orderly international trade system."

Jan 1, 1983

For the last few years, a new and innovative technique has been successfully used to determine refractory and castable thickness in various metallurgical vessels. The acousto ultrasonic-echo (AU-E) technique uses stress waves to detect metal penetration and delaminations within refractory linings. In addition, it is capable of measuring the thickness of refractory layers and build-up material. The inspection and measurements can be carried out while the furnace is in full operation. The present paper discusses the principles of the AU-E technique, and its advantages and limitations. A number of case studies are presented to demonstrate various capabilities of this new Non-Destructive Testing (NDT) technique.

Jan 1, 2005

By Lanny Pasternak

"This article is directed at plant production, engineering and maintenance personnel. Seldom does any industrial operation take the time to study the costs involved in the generation of what is probably their most expensive plant utility energy source.IntroductionIn the typical industrial plant in Canada, a 200 hp, 900 cfm, air compressor costs about $60,000* per year to operate (Fig. 1). In 1989 when BC Hydro embarked on their industrial energy management program Airflow Energy Ltd. were asked to spearhead the “Efficiency Compressed Air” portion of that program with a mandate to perform onsite overview surveys and physical hands-on testing of some 300 selected industrial plants throughout British Columbia for compressor efficiencies and wasteful air leaks (Fig. 2). The program duration lasted until 1995, during which time a tremendous amount of data were amassed relating to equipment types, clients’ operating habits, end-use applications and operating costs.During the past six years, Airflow Energy also performed somewhat similar surveys but on a smaller scale in Alberta, Ontario, the United States and the Republic of China. It was no surprise to find some inherent equipment concerns related to efficiency as well as neglected energy wasteful air leaks, so British Columbia was not alone and the problems appear somewhat universal."

Jan 1, 1996

By M. Clotilde Apua, A. F. Mulaba-Bafubiandi

"The efficiency of hydrochloric acid (HCl) leaching of gold from low grade gold-bearing material has been investigated in the presence of sodium hypochlorite (NaOCl) to produce in situ chlorine gas which is an oxidizing agent able to oxidize gold metal to its soluble forms. The effect of concentrations of HCl, NaOCl, and mixtures of HCl + NaOCl was sought. Iron and potassium present in the feed were leached and consumed all the HCl. Gold found as inclusion in pyrite was not exposed to the lixiviant. Therefore, leaching of gold from low grade gold-bearing material in aqueous chlorine solution is not an effective process for now.INTRODUCTIONHydrometallurgy of gold is commonly based on cyanide leaching solution. Due to the environmental concerns related to cyanidation and mercury processes, and inefficiency of cyanide gold leaching to dissolve refractory ores, sustainable alternative lixiviant systems, capable of generating gold (I) and gold (III) complexes must be studied. Amongst non-cyanide gold lixiviants there is the chloride/chlorine system (Hilson and Monhemius, 2006; Senanayake, 2004; Pilsniak and Trochimczuck, 2007; Wang et al., 2007; Reeves et al., 1999; Khodadad et al., 2008).In practice, the most oxidizing agents utilized for the leaching of gold as chloride, are chlorine (Cl2) or hypochlorite (HOCl) which are either generated in situ by suitable reaction or added in solution (Adamson, 1972). The dissolution of gold concentrate using hydrochloric acid, sodium chloride and sodium hypochlorite (Cl-/HOCl system) were studied (Puvada and Murthy, 2006). The effect of NaOCl and NaCl concentrations were also investigated. The leaching was performed under the following conditions; time: 4h, solid–liquid ratio = 1:4, at room temperature. It was found that the increase of the NaOCl concentration from 25 to 75 g/L did not have any meaningful effect on the recovery of gold which was about 30% (experimental conditions; S/L ratio = 1:4, NaCl concentration: 25 g/L, HCl concentration: 0.35 M). It was also found that from 25 g/L to 200 g/L NaCl, the recovery of gold rose from 30% to 40% (experimental conditions; S/L ratio: 1:4, NaOCl concentration: 25 g/L, HCl concentration: 0.35 M)."

Jan 1, 2012

By A. Bauer

This paper describes the trends in recent years in explosives formulated to produce larger blast-hole spacings and over-all lower drilling and blasting costs in hard formations. A consideration of current rotary drilling costs per ft of hole and per ton of muck versus hole diameter indicates that it is now possible that we shall see much further use of lower-energy-content, lower-cost slurries and dry mixes, and larger-diameter and, in many instances, cheaper blast holes. These will be drilled on current or slightly larger blast patterns to yield the same energy input per ton of rock and similar fragmentation at lower costs.

Jan 1, 1968

Adaptive processing is often related to the mineral composition of the mining block currently processed. The portions of waste, ore and secondary product minerals considered are always positive and typically sum to 100% (i.e. a composition). A typical solution to predict block averages of spatially dependent quantities would be block kriging. However, kriging is based on spatial correlations and it has been repeatedly shown that correlations of compositional data are spurious and blurred by the constant sum constraint. Aitchison (1982) proposed a general solution for compositional problems, based on transforming the compositional data to a set of logarithms of ratios of components, and analysing the transformed scores. The transform is chosen to be invertible to ensure that no information is lost in the process. This methodology avoids spurious correlation problems and ensures coherence between results obtained with different subcompositions. Pawlowsky-Glahn and Olea (2004) adapted the approach for point-support geostatistics, allowing the prediction of point compositions from spatially neighbouring data, without the artefacts induced by standard multivariate cokriging. Unfortunately upscaling the results of this approach with block cokriging is not straightforward, because of the nonlinearity of logratio transforms. Furthermore, we have to consider those nonlinearities created by the dependence on the block composition of extraction efficiency and processing costs of the possible processing choices. This paper proposes a solution for predicting the conditional expectations of the benefit of processing the block with each processing choice using geostatistical simulations of the local values of the composition and the resulting block integrals. The computation for a large number of blocks can be done efficiently using Cholesky decomposition. The approach also allows the calculation of prediction errors for expected compositions and expected benefit at almost no additional computational cost. Such compositional approach is necessary, for example when processing choices depend on proportions of certain minerals after other components have been removed; or if processing alters the composition in a multiplicative way, by partially removing a portion of some components.

Aug 1, 2013

By Daniel Cluff

Frozen backfill for mining operations in permafrost must be delivered in such a state so as not to thermally impose on the host rock surrounding the filled stope. The placement process, the material strength demand, and the freezing time delay are the parameters that control the applicability of the method. A two-year research program was carried out in the field and using a laboratory-scale apparatus, designed to simulate a pour of frozen backfill, to study the mixing, thermal properties and segregation. The frozen rock and tailings must be at a below zero temperature and get fully wetted so the surfaces cause adherence of the particles to one another and enhance the solidification of the poured backfill. The results provided a recipe and a process for mix design for open stoping operations in cold regions. The testing evaluated the sensitivity of the test parameters that included the amount of water added in the mix, the temperare of water, the rockfill/tailings ratio, and the temperature of solid constituents.The paper presents the result of this environmentally friendly, innovative technology. The distribution of the materials and the mixing process are instrumental in achieving the properties required for open stoping applications.

Oct 1, 2010

By J. W. Smith, J. G. Eacott, D. H. Napier

"Three hydrometallurgicat processes (Noranda chloride leach, B. C. Research biological leach and Sherritt-Cominco activated oxygen leach) and the Noranda pyrometallurgical process have served as the basis for design projects in the final year of the chemical engineering program at the University of Toronto. Each member of a team of five or six students devotes about 200 hours to the project and the final report is expected to include an economic analysis.None of the processes has been developed to full- scale plant, nor, in the case of the B.C. Research and Noranda processes, were pilot plant data available. Nevertheless, the designs developed provide a useful basis for a preliminary estimate of capital and operating costs and for a preliminary assessment of project feasibility.This paper discusses the approach used in the design projects with respect to engineering and economic aspects, and outlines the educational features and benefits of such a program as well as some of the problem areas that arise.IntroductionAs part of the undergraduate degree course in chemical engineering at the University of Toronto, students devote some 200 hours to a design project in their final year. Hydrometallurgical processes, not yet proven at the commercial scale, have been selected for study. The students are required to develop laboratory and / or pilot scale results into a conceptual plant design, using sound engineering principles. Capital and operating costs are then determined and a preliminary feasibility study and economic analysis are carried out."

Jan 1, 1986

By David L. Sprott

This paper presents an evaluation of underground-to-surface haulage options for a relatively large deposit. Specifically, it presents a recommended haulage option to provide the greatest value to the Project. Options considered included conventional truck, trolley-truck, conveying and shaft hoisting. The work was done at the level of a preliminary assessment as input to an internal pre-feasibility study. The Base Case for the analysis in this study was a Long Hole Open Stoping option (LHOS) using conventional truck haulage. Two scenarios were considered for the evaluation and included: 1. The current resource to ~700 m depth. 2. An expanded resource to ~825 m depth. The haulage options evaluated included three trucking options, three conveyor options and two shaft options. The paper presents the results from evaluating these options within the two mining scenarios using a Discounted Project Cost (DPC) comparison. Recommendations are made for the options that will provide the greatest overall value to the project.

May 1, 2008

By C. J. Coulson, G. A. McKay, A. M. Cormie

"The Leitch mine, in the Beardmore area, Thunder Bay district, Ontario, is a part of the Leitch estate. It includes a group of patented claims, staked by P. A. Leitch of Port Arthur early in the century, along bands of jasper, hematite, iron-bearing slates, carbonatized schists, and greywacke, commonly known as 'iron formation'. The folding and shearing in these variably interstratified beds is a striking structural feature. The vein pattern is very definitely related to these structures.ROCKSThe rocks in the area are typical Keewatin lavas-greenstone-overlain by a series of Timiskaming sediments consisting of arkosic greywacke, iron formation, slate, greywacke, conglomerate, and greywacke, in this order from the contact. The sedimentary beds are generally conformable with the older rock contact except on local folds.Small intrusions of diorite occur as nearly vertical dykes and are believed to be of Algoman age. To the northwest of the mine there are larger intrusions of granodiorite belonging to the same period.Several dykes of quartz diabase up to 100 feet in width, striking generally north and south, with a vertical dip, cross the property. These have been classified by W. C. Laird as pre-Keweenawan in age. One of these dykes in particular is of importance for it cuts through the No. 2 vein and serves as a pillar when stoping. It is approximately 6 feet wide.The youngest rock type represented is a sheet of olivine diabase that extends over an area of thousands of square miles in and around lake Nipigon. It underlies most of this area and its outcrops form some of the most interesting topographical features, with fault scarps rising hundreds of feet. In the vicinity of the mine shaft the sheet is about 600 feet thick and extends from a depth of 1,871 feet to approximately 2,470 feet. It has a dense, hard, chilled margin and a sharp, tight contact. It intruded the sediments with very little lateral disturbance. The chief effect was baking, which darkened and hardened the greywacke near the contact. The sheet dips flatly to the cast."

Jan 1, 1954

By Dwayne D. Tannant

Digital photogrammetry allows rapid, remote measurement of millions of points, thus providing an unprecedented amount of spatial information. Research is being conducted to explore practical applications of digital photogrammetry for monitoring, surveying and mapping in surface mines. The performance, accuracy and operational ease of digital photogrammetry are discussed and practical aspects of conducting digital photogrammetry surveys are reviewed. Case histories from coal, diamond and limestone mines are presented.

May 1, 2006

By G. D. Garland

The influence of natural electric currents, induced in the earth by changes in the earth's magnetic field, on the electric logging of boreholes has not always been recognized. Measurements made with fixed electrodes of changes in the vertical potential gradient in a hole near Calmar, Alberta, have indicated the effect of earth currents related to magnetic disturbances. It is found that appreciable errors in self-potential logging could arise during periods of magnetic storms, but the precise pat-tern of disturbance in any area seems to depend on the local structural conditions. As the amplitude of the natural earth currents increases toward the auroral zone, it is suggested that periods of magnetic disturbance be avoided, if possible, when electric logs are taken in the northern part of the western sedimentary basin. NATURAL electrical currents flow continuously near the surface of the earth, apparently as a result of electromagnetic induction

Jan 1, 1962

By S. Xu, A. Ramesh, F El-dabbagh, Z. Fang, A. Sobhy, J. A. Kozinski

Waste remediation is a goal that will be driven forward by economic conditions. As the cost of waste disposal increases, new methods of waste reduction will become economically attractive, and will be implemented. It is difficult to imagine, however, a time when there will be no waste generation. For the foreseeable future, despite effective reduction practices, there will still be hundreds of millions of tons of waste that must be destroyed or controlled to protect the public health and the sanctity of the environment. To remain faithful to environmental covenants, the mineral and metallurgical industries will face these new challenges. This paper discusses novel waste remediation approaches and techniques focusing on hazardous wastes and thermal remediation. Aspects concerning technological and environmental importance are examined. Solutions for neutralization of environmentally hazardous compounds are proposed.

Jan 1, 2004