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By J. Carr

This paper discusses: (1) the need for Western Canadian coal in eastern Ontario Hydro plants; (2) design parameters-unit trains, year- 'round receiving from trains, and shipping (Great Lakes season); (3) equipment chosen-dumper-indexer, outhaul conveyor, yard belt, stacker, reclaimer, surge-bin feeders, shiploader, docking system and dust control; (4) foundation and soil conditions-dumper house, yard belt, surge bin and dock-piling-runway; (5) winter conditions- thaw shed, feeder, lump breaker, beltings (oil), and dust control and disposal; and (6) operations to date.

Jan 1, 1979

By M. Matsuda

The Hitachi refinery of Nikko Smelting & Refining Co. Ltd. began its electrolytic copper refining operations in 1911. In December 2002, the refinery changed its operation scheme by introducing the ISA permanent cathode technology for the first time in Japan. The change resulted in higher productivity, better cathode quality, and lower operational costs. The operation has been continuously improved to reach a 20% higher production capacity than the original one. For the electrolyte purification process, the Hitachi refinery has developed a new process for removing impurities. The process involves As, Sb and Bi adsorption from the electrolyte by means of chelating and ion exchange resin. The new resin process will achieve higher efficiency in removing impurity.

Jan 1, 2007

By K. Wood, R. McIvor, P. Blythe, M. Lavallee

A new analytical approach for characterizing and improving the performance of ball milling is presented. Individual ball mill circuit design and operating variables can be related to overall circuit performance through two distinct parameters for classification and breakage. The ball mill circuit functional performance equation is presented.Total mill x Classification x Test specific x Grinding power draw system efficiency grinding rate rate ratio= Production rate of new product size materialExamples from industrial plants and applications in the research and development field are discussed.

Jan 1, 1990

By M. DeLucia

"Over the past 15 years, technical innovations have improved the properties and performance of monolithic refractories. As these improvements have occurred, aluminum cast-house refractory selections have changed from brick to monolithic refractories supplied as either cast in place, or precast, ""Big-Block"" installations. A review of the properties of monolithic and brick refractories is presented, as well as the technical advantages of brick for highly demanding applications. Operating conditions and issues such as temperature, alloying, corundum growth and other variables are also reviewed."

Jan 1, 2004

By Robert B. Parsons

"The annual onslaught of provincial budgets and tax changes is complete, and once again the Canadian taxpayer is being asked to dig deeper into his pocket to fund old and new programs. It is noteworthy that 1987 tax reform promised lower taxes, but a broader fax base. Five years later, we still have the broader tax base, but the lower faxes have gradually crept up to pre-tax reform levels. Surprise! Surprise!IntroductionThe last edition of Tax Notes commented on some important proposals announced in Manitoba's 1992 budget. In this issue, Tax Notes summarizes the 1992 budget proposals of British Columbia, Ontario and Quebec. These budgets reflect the continuing trend of transferring responsibilities and the related costs-from the federal government to the provinces. As well, the budget papers bear witness to the respective governments' political stripes. British Columbia, Ontario and Quebec are seeking higher tax revenues. Only Quebec continues to acknowledge the importance of the mining industry in its annual budget documents."

Jan 1, 1992

By W. Evans, T. Steis

"Sulphide ores under certain circumstances will react with explosives to generate an autocatalytic chemical reaction. This reaction is exothermic and results in the production of large volumes of poisonous gases and creates an unsafe, unstable condition with the possibility of a low energy deflagration or even a detonation of the loaded hole. This paper outlines the conditions that need to exist for such a reaction to take place and the precautions necessary to minimize or eliminate the problem in areas of reactive ore. A special case study involving a northern Ontario mine will be detailed.IntroductionOne of North America's leading underground gold producer's processes over 6500 tonnes of ore per day from an orebody containing high concentrations of sulphides. After six years of problem free operation, the mine experienced two serious reactions in two months between the sulphides and AMEX II, the ammonium nitrate and fuel oil explosive it uses."

Jan 1, 1995

By Huan-Qiang Zhang, Gang-Hai Huang, Yu-Yong Jiao, Fei Zheng, Zhang. Xiu-Li

An efficient and accurate three-dimensional (3-D) contact detection algorithm is of vital importance in large-scale computing of discontinuous deformation analysis. The contact detection algorithm takes up a large proportion of the whole calculation time because of the increasing calculation number in three-dimensional case. For block systems which consist of convex polyhedrons, the efficiency and accuracy of the contact detection algorithm is a great challenge. The presented contact detection algorithm in discontinuous deformation analysis (DDA) method is carried out in three phases: the global neighbour searching, the local contact type searching and the contact transferring. A contact detection algorithm for 3-D DDA is presented with some improvements on the three phases. A grid-based global neighbour searching algorithm is used to eliminate unnecessary neighbour blocks to the exact number. The local contact type searching includes two steps. In the first step, the common plane method is used to determine the contact type between convex polyhedrons. In the second step, the contact pairs detected by the common plane method are divided into four basic types. In the third phase, the four contact types are transferred into two basic contact types, vertex-to-face contact type and edge-to-edge contact type, which are managed in a uniform procedure. Three verification examples are calculated, the results show that the proposed algorithm based on the three contact detection phases is robust and efficient.

Jan 1, 2015

By Stephen G. Mlot

Technical Study Work ?Technical study work enables informed decisions: -Obtain a higher price for a quality asset -Minimize expenditure on a project that won?t provide adequate returns -Optimize expenditure on a project to capitalize on the potential return

May 1, 2013

By K. A. Lewandowski

Agglomeration of ore used in heap leaching allows for the immobilization of fine particles that would otherwise migrate and cause permeability problems in the heaps. For copper ore, binders are needed in order to make stable agglomerates. However, the majority of binders break down when introduced to an acidic environment, allowing fine particles to be released from the agglomerate surfaces. These particles migrate through the heap impeding solution flow, leading to a decrease in metal recovery rates. The authors have developed a series of testing procedures to determine the acid resistance of several binders. Only five binders were shown to be acid resistant in soak tests, decreasing fines migration by up to 93%, compared to tests which were agglomerated with leach solution, raffinate, as a binder. Flooded percolation column testing also showed that these binders were able to reduce the "slump" of the ore by up to 82% and increased the hydraulic conductivity by up to 90%, when compared to agglomerating with leach solution alone. The use of binders in the agglomeration of copper ore also showed no negative effects on the bacterial populations throughout a leach cycle.

Jan 1, 2007

By Y. Vermeulen, J. Simoes, P. Guillo, A. Di Donate

New design techniques have been developed to optimize continuous casting (CC) refractory components. The overall objective is to increase CC productivity as well as steel quality by using optimized refractory from tundish-to-mold. These techniques allow the prediction of steel and refractory chemical interactions and, thus, steel chemistry evolution as well as build up and corrosion occurrence. Specific fluido-dynamic models (CFD) have also been developed to better take into account the physical parameters at the steel/refractory interface and to optimize steel flow control. The CFD model can be coupled with refractory chemical interactions to simulate steel chemical evolution. These two different approaches result in shape and material modifications. They are completed by dedicated thermal stress analysis in order to improve thermal shock resistance. The mechanical FEA evaluations take into account specific mechanical behavior of refractory components as well as high temperature evolution of their properties.

Jan 1, 2004

By A. I. A. Salama, M. W. Mikhail, R. J. Mikula

"The Coal Research Laboratory (CRL) of CANMET along with other research organizations in coal-producing countries envisage major benefits from computer applications in coal preparation, Some of these benefits are greater system flexibility, improved coal preparation plant performance efficiency and efficient utilization of manpower, all of which result in economic benefits. Computers can be applied for both on-line and off-line purposes; this paper focuses on the on-line applications from the process control point of view.A critical discussion of the different analog and digital process control systems is presented. Recent developments in Great Britain, West Germany, Poland and Australia on automation and instrumentation using on-line measurements of coal ash and moisture contents are identified.The CRL research and development strategy aimed at achieving on-line computer control of an automated coal preparation plant is presented.IntroductionIn the past twenty years an enormous progress in the area of computer technology has been noticed. Computer applications in industrial processes offer greater system flexibility, improved plant performance efficiency and efficient utilization of manpower. Significant computer control development in mineral processing has already been achieved. Although progress has been made in the area of computer applications in coal preparation, more effort is needed to utilize the full potential.The computer applications in coal preparation can be viewed as off-line and on-line. Considerable progress has been reported in the area of off-line computer applications, especially in the areas of modelling, performance evaluation/prediction and statistical analysis. However, only modest progress in on-line applications has been reported(1-7). This paper will focus on: online instrumentation and process control applications, different analog and/or digital control systems, on-line automation and instrumentation in other countries and CRL strategy toward pilot plant automation."

Jan 1, 1985

By S. Kamado

Development of new SF6 alternative cover gas with low global warming potential is strongly desired for melting and casting of magnesium alloys. We have tried to apply several kinds of HFC and HFE gases with low potential from 30 to 950 as protection gases to AZ91D alloy melt in the temperature range of 650 to 800°C. As a result, protective film consisted of MgF2 and MgO is formed on the melt surface and ignition-proof effect is sufficiently obtained at all the temperature ranges even when flow rates of mixed gases containing CO2 as a carrier gas are almost the same as those using SF6 gas. Reduction of global warming potential exceeds 98% at 650°C and 89% at 800°C in comparison with a mixed gas of CO2 and SF6.

Jan 1, 2006

By P. D. Soares, H. R. Bullis, R. A. Hureau

"Echo Bay's Lupin Operation has produced more than 2.15 million ounces of gold since start-up in 1982. The mining method used to the£ present time has been longhole open stoping using trackless equipment. Because direct measurement of the open stopes has not been possible until recently determining the exact quantity of unplanned dilution in previously mined stopes has not been possible. Estimates of dilution hove been mode using comparisons between production tons and grades against ore reserve tons and grades.This paper discusses tracking of grade and tonnage measurements from reserve estimation through production. Comparisons between estimated and actual tons and grade are presented~ along with a brief description of methods used at the Lupin operation to control dilution."

Jan 1, 1994

By D. K. Storer, W. Lee, S. Tkach

"A microcomputer-controlled multi-probe K-40 monitoring system was developed internally for the Phase II mill at the Lanigan potash mine. The K-40 probes were mounted in a variety of positions in several process streams, ranging from dry ore on a conveyor belt to brines and slurries. A description will be presented of the objectives, the equipment and the difficulties encountered in correlating results.IntroductionThe successful control and optimization of most metallurgical processes involves monitoring not only physical parameters such as flow rate and temperature, but also the chemical compositions of critical streams. Composition has proven difficult to measure on -line in industrial scale processes. However, in potash processing there is a convenient chemical parameter that has long been utilized to measure in situ the concentration of potassium chloride (KCl). Potassium has a long-lived isotope which is slightly radioactive. K40 decays by beta elimination to Ca40, ultimately radiating a characteristic gamma-ray photon. This gamma emission when detected by scintillation counter can be used to estimate the concentration of potassium in a process stream."

Jan 1, 1990

By Rodrigo Craig Cerello

The Brazilian economy has always presented a strong correlation with the mineral activity. Since colonization days, due to the territorial expansion caused by the explorers search for gold, mining in Brazil became a basic sector of national economy. Currently, the Brazilian mineral sector¹ estimates a 550% production increment (Figure 1A) in the last 10 years, reaching the US$ 50 billion value, reflecting the increased global demand for raw materials from mineral origin. According to the Brazilian Constitution², mineral resources belong to the Federal State and, consequently, their exploitation must be authorized, under penalty of engendering federal crime. Furthermore, activities of this nature are prone to cause environmental degradation such as, but not limited to, deforestation, pollution, soil deterioration and water contamination. The GPEMA represents the forensics group of the Brazilian Federal Police responsible for the technical analysis of traces related to crimes against the environment and consequently, illegal mining cases.

Aug 1, 2013

By M. Oliazadeh

The bioleaching of fine low grade copper sulfide ore is described. A sample of ground (> 1 mm) copper ore from Sarcheshmeh, Iran, was subjected to a series of agglomeration procedures and subsequently leached. The best agglomerate was obtained by using lime and sulfuric acid as binders. A column bioleaching test of agglomerated ore was then run for 105 days along with a non-inoculated control column having thymol as bactericide. The results show that about 77.5% of copper was extracted in the bioleaching, whereas the control column achieved only 57% copper leaching.

Jan 1, 2007

By Ngonidzashe Chimwani, David Glasser, Diane Hildebrandt

"Milling circuits play an important role in achieving the desired product; tonnage, size distribution and properties, since they are directly linked to the comminution energy consumption for the whole process. A grinding model with a mathematical simulation was developed for an open milling circuit with a scalped feed from a hydro-cyclone. The circuit was optimized by determining the optimal conditions in terms of energy consumption which would produce a floatable product having a desired size range (i.e. -75 +9 µm) for a platinum-bearing ore. The simulation results showed an operating region comprising the best combination of the ball filling and mill speed to achieve the highest production of a floatable size class, with the minimum energy consumption.INTRODUCTIONBall milling is usually conducted in closed circuits in order to achieve a desired product size without material overgrinding. The technological importance of optimising milling circuits cannot be overemphasised (Toneva and Peukert, 2007). Previous work has brought significant insights into the benefits of modelling milling circuits (Austin et al., 1984; King, 2012; Toneva and Peukert, 2007). However, the ability to model these circuits is dependent on the performance of the classifiers and the fidelity of the grinding mill model used compared to the actual circuit (Toneva and Peukert, 2007). Austin et al. (1984) identified five types of milling circuits as shown in Figure 1 namely; the grinding circuits employing mill in an open circuit, normal closed circuit, reverse closed circuit, open circuit with scalped feed, and, the combined closed circuit. Depending on the presence of the first classifier, the second, or both as well as their corresponding loops (streams), the combined circuit (e) can reduce to; an open (d), a normal closed (b), an open circuit with scalped feed (c) or a reverse closed circuit (a). In the case of an open circuit, the mill is operated without being directly influenced by a classifier. The normal closed circuit does not have the first classifier and therefore the make-up feed is the actual feed stream. Conversely, the reverse closed circuit keeps only the first classifier. The open circuited with scalped feed has only the first classifier but does not have the second one. The overflow stream from the classifier is mixed with the mill product to form the final product for the downstream process."

Jan 1, 2016

By I. H. Warren

"An analysis of form-coking processes is presented in terms-of their fundamental mode of operation and their relationship to other coking processes. Their possible future role in cokemaking is assessed. IntroductionAny consideration of prospects and possibilities for form coking must commence with the iron and steel industries-their likely future growth pattern on a world and regional basis and the potential direction of future developments in iron and steelmaking technology.From the numerous estimates which have been made of the future consumption of steel, it would appear that a growth rate of 3lllo between now and the year 2000 is likely. Radical changes in steel making technology are unlikely to be commercially adopted on any significant scale during the next twenty years . However, widespread commercialization inter alia of continuous casting and direct reduction, growth of electric furnace steelmaking and a decrease in coke rates will all contribute to a growth rate for metallurgical coke that certainly will be less than that of steel."

Jan 1, 1980

By George P. Demopoulos

In this paper the author will provide an overview of over 20 years of research & developments in the area of hydrometallurgical arsenic immobilization that culminated recently in the industrial implementation of the atmospheric scorodite process. The paper will consider various aspects of arsenic fixation in the non-ferrous metal industry from the iron-arsenic co-precipitation process employed to arsenic-bearing effluent solutions; to autoclave processing of arsenical copper and gold feedstocks and the fate of the in-situ formed iron sulphato-arsenate precipitate phases; the precipitation and stability of scorodite; the possible stabilizing role of mineral phases like yukonite, and the development of "scoroditeplus" processes employing novel encapsulation strategies. Emphasis is placed on the characterization and long-term stability of the various forms of arsenic-immobilized phases under either oxic or anoxic conditions over a wide pH range and the establishment of critical links between process parameters and hazardous material stability, contributing thus to advancement of new generation safe and sustainable waste management technologies.

Jan 1, 2014

By J. A. R. Faucher

"Autogenous grinding may be an efficient and economical solution to your ore comminution problem.An important potential economic advantage of autogenous mills results from the availability of very large capacity units.Autogenous grinding could be more economical in terms of both capital and operating costs.Satisfactory pilot plant testing and thorough economic evaluation are required for a sound decision in comminution plant selection.INTRODUCTIONMankind's first weapon was probably the wooden club, but men soon learned to shape, smooth and polish stone for tools and weapons by pounding and rubbing them with sand and water. It was only about four thousand years ago that rocks were first broken to concentrate, smelt and return the metals they contained. In spite of our recent great technological advances we still break rock in essentially the same manner that was used thousands of years ago - by pounding, rubbing and squeezing - and we still waste much energy and metal in the process"

Jan 1, 1969