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By M. Sokoto, H. Hata, K. Nishina, K. Haiki

Fluoride ions in zinc electrolyte cause corrosion to aluminum cathode plates at zinc electrowinning process, so we have developed an iron compound as a fluoride ion adsorbent used in zinc sulfate solution. The iron compound is synthesized from FeC13 solution with a small amount of sulfate ion by neutralizing reaction with Na2CO3 solution. The fluoride ions adsorbed on the surface of the iron compound are desorbed in alkaline solution and the iron compound can be reuse as a fluoride ion adsorbent. Moreover, if adsorption capacity of the iron compound decreases, it can be dissolved in HCl solution and re-synthesized.

Jan 1, 2008

By H. Miki, S. Wheatley

The addition of precipitated silica greatly enhances chalcopyrite leaching in the presence of sodium chloride at moderate temperatures (65-90°C) in acid media with ferric ions as the oxidant. The beneficial effect increases with the increase in chloride concentration and temperature. The addition of sodium silicate and silica sand has no significant influence. The analysis of solubility data in acid/salt solutions indicates that the solubility of silica as Si(OH)4 as the dissolved species is controlled by the activity of water, as expected from the hydration theory. Kinetic analysis shows the trends that copper dissolution from chalcopyrite in the presence of precipitated silica with sodium chloride follows a shrinking sphere model indicating a chemically controlled surface reaction. The effect of temperature on copper dissolution in the presence of both precipitated silica and sodium chloride was also larger compared to the results in sodium chloride alone. The SEM analysis shows that chloride and silica facilitates the precipitation of sulfur on the surface of the silica particles rather than the chalcopyrite particles which avoids the blockage of the mineral surface and thus improves the leaching kinetics.

Jan 1, 2014

By Min-Yuan Cheng

Heavy rainfall and typhoon oftentimes cause the collapse of hillslopes across mountain roads. Disastrous consequences of slope collapses necessitate the approach for predicting their occurrences. In practice, slope collapse prediction can be formulated as a deterministic classification problem with two class labels, namely ?collapse? and ?non-collapse?. Nevertheless, due to the criticality and the uncertainty of the problem, evaluating the collapse susceptibility of an area is a challenging task. This study proposes a novel Artificial Intelligence (AI) approach, named as K-Nearest Neighbor Based Bayesian Classifier (KNNBC), to deal with slope collapse assessment. In the proposed model, Bayesian inference is used as a framework to achieve probabilistic prediction of slope collapse. Meanwhile, K-Nearest Neighbor (K-NN) is employed as a density estimation technique. Equipped with probabilistic outputs, the K-NNBC is able to yield predictions with different levels of confidence and diminish misclassified cases. Experimental results point out that the proposed model is very helpful for decision-makers in slope collapse assessment and disaster prevention planning.

Aug 1, 2013

By M. Sengupta

International trade in minerals plays a very important role in the economic growth of many nations. Several less developed countries a1•e heavily dependent on their mineral exports for earning foreign exchange, which is needed for industrialization. Mineral exporting nations experience many problems in international mineral markets; the most important are tariff barriers, deteriorating terms of trade, instability in metal prices, etc. The formation of international mineral cartels to raise prices can be successful only to a limited extent and only for a short period of time.

Jan 1, 1976

By L. Jones, S. R. Lawrence, A. R. Holloway

Whilst dense medium separation is best known for its ability to concentrate diamond and coal deposits, the process is now being employed in southern Africa as a pre-concentration step to improve the economics of platinum group metal and nickel ores. DMS plants built for these industries (such as the 1600tph unit at Tati Nickel, Botswana), are spearheading an expansion in this area by reducing mine and process operating costs yet maintaining economic metal recoveries. This paper provides an overview of DMS technology and examines the economic benefits available to North American operators and projects, with recent case studies as reference.

Jan 1, 2009

THE Michipicoten area, one of numerous iron-bearing "Archean" segments in the Shield, contains two main types of iron formation, a normal Keewatin-type, consisting of interbanded chert, siliceous magnetite and jasper, and, gradational to this, a carbonate-sulphide type which contains large de-posits of siderite and pyrite. The carbonate-sulphide type of iron formation bears a direct and intimate relationship to the volcanic development of the area; it there-by affords some insight into genetic problems of Archeanron formation in general. The purpose of this pa-per is to summarize the geological setting of Michipicoten iron formations and to briefly review genetic aspects of recent work in the area. GENERAL GEOLOGY in largely by assorted volcanics and sediments of the Michipicoten series and younger, regional granite masses. (Fig. 1). The Michipicoten series comprises a thick assemblage of mixed flows and pyroclastics together with elastic sediments and banded iron formations. The volcanics belong to the Andesite-Rhyolite Association, and characters-

Jan 1, 1961

By R. Hagiwara, S. Kobayashi, K. Yasuda, T. Nohira, K. Kondo

To establish a process for the electrochemical recovery of rare earth elements from used magnet scraps, the electrochemical formation of RE-Ni alloys in molten NaCl-KCl-RECl3 salt at 973 K was investigated. Cyclic voltammetry and open-circuit potentiometry indicated the formation of several phases of RE-Ni alloys. The formation potential for each RE-Ni alloy phase was determined from the results of scanning electron microscopy and X-ray diffraction of alloy samples prepared by potentiostatic electrolysis of a Ni plate electrode at various potentials. The optimum electrolysis conditions for the separation of Nd, Dy, and Pr are discussed.

Jan 1, 2014

By O. Peters, D. Lascelles, R. Caldwell

Ageing tests on a crushed Cu-porphyry ore were conducted to assess the impact of sample oxidation on flotation performance. The objective of the testwork was to simulate ageing of ore that would be blasted through block caving but not milled for possibly several months. Ageing was performed in specially designed columns, using site and deionised water to keep the samples moist over the entire ageing period. Samples from each ageing interval (0, 0.5, 1, 2, 4, and 8 months) were examined for physical and metallurgical changes resulting from the ageing process through chemical analyses, size analyses, and batch flotation tests.

Jan 1, 2009

By Gerry Doeksen

The paper deals with three case studies: (a) the handling of wet concentrates (5 to 8 per cent moisture) through feed bins; (b) the handling of the same product in rail cars; and (c) the handling of dry concentrates (less than 0.5 per cent moisture) through feed bins. In each case, the paper discusses the problems of rat-holing. In each of cases (a) and (c), there is a discussion on the consequent extreme variations of feed rates coming from the feeders, making automation of process control difficult to impossible. Currently available bin-flow theory and flow property tests are used as aids in redesigning the bins. The paper concludes with illustrations of the final results after the redesigned hoppers were installed and tested. There is also a discussion on the advantages of the new mass-flow bins on adjacent feeder performance.

Jan 1, 1970

By H. Lazreg

This paper presents an evaluation of surface resistivity techniques as a tool for delineating salt-water intrusion in Shippegan, N.B. The study consisted of resistivity profiling, resistivity soundings and a limited number of induced polarization soundings in selected areas in the Province of New Brunwick. The results from resistivity profiling indicate that when seawater intrusion occurs in a sandstone formation the resistivity contrast is sufficiently large to allow a precise delineation of the intrusion. A formula is then derived to convert resistivity values to chloride concentration in the "cone of intrusion". The results from resistivity soundings showed that shaly formations may have resistivities as low as seawater-contaminated sandstone. An indeterminacy has resulted from this resistivity overlap. A limited number of IP soundings were performed in an effort to resolve it. The results showed that IP can be of appreciable help in resistivity interpretation.

Jan 1, 1972

By W. A. Roliff

The renewed interest of the past few years in the Appalachian and Michigan oil provinces has not, as yet, created any marked increase in activity in Southwestern Ontario. During 1960 development drilling in-creased somewhat over 1959, but exploratory drilling decreased slightly. More attention was devoted to the deeper horizons, but lake drilling de-creased considerably. Oil production reached a new peak and gas production increased slightly. During 1960 an interesting oil and gas discovery was made in the Cambrian and gas discoveries six miles off-shore in the eastern part of Lake Erie were made in the Clinton-Cataract zone of the Silurian. This paper reviews activities during 1960, summarizes the discoveries made to-date and the pertinent exploration data relating to the prospects of the region and discusses some of the economic aspects of exploration and development. D URING the last few years there has •been a marked renewal of interest in the old petroleum

Jan 1, 1961

By A. M. S. Hussein, B. E. Rogers

Progressively more stringent emission limits and advances in regulations and enforcement have made air compliance more difficult for metallurgical facilities. This has historically required improved collection and treatment of stack sources. Fugitive emission reductions are now increasingly required to achieve compliance. Typically small in magnitude, fugitive emissions have a disproportionate impact on ground level concentrations, can be visible to the public and can influence workplace health and safety. Moreover, these emissions are complex, as they are spread over multiple sources, distance and time and are affected by various activities and conditions. As such it is difficult to find, define and monitor these emissions and their impacts. This difficulty translates to the design of emission reduction measures and operational requirements. This paper presents an overview or ‘heuristic’ of fugitive emissions management for compliance in existing operations. This includes aspects such as the impact of regulations on project scope, approaches to developing a comprehensive emission inventory, considerations for solution development and the plant’s role in sustaining compliance once achieved. Case studies are presented to demonstrate how portions of this approach have been applied.

Jan 1, 2015

By H. C. Gunning

DURING the past year the Cadillac-Malanie area in northwestern Quebec has been catapulted to the front as one of Canada's most active gold mining districts. Late in 1934 the area was lolling along in the doldrums, with one producing mine and a handful of active prospects. 1935 passed with only slightly increased activity, but saw the start of production at Canadian Malartic mine. Lightning struck in April, 1936, when a new and phenomenally rich ore-body was found in O'Brien Gold mine, and by midsummer the camp was ablaze with activity. An important new discovery on the Pan-Canadian property, and pleasing underground developments at Sladen Malarric, East Malartic, and Lapa Cadillac, in addition to other new developments, lent fodder to the flame, and at present several dozen properties are being actively developed. For the past three seasons, the Geological Survey of Canada has been engaged in a fairly detailed study of the geology and mineral deposits across Cadillac, Malarric, and Fourniere townships. Ir is the purpose of this paper to present a brief preliminary statement of the structural and economic geology and to discuss some of the more important problems that have been found to exist. The reader is requested to remember that the paper is a preliminary one and that therefore the conclusions presented are open to revision. It is impossible to make full acknowledgment for help received, for the writers are indebted to practically every operator and prospector in the area for generous co-operation in the work, and to several private, provincial, and federal geologists for data and frank discussion of problems encountered. Over a score of student assistants from McGill, Queen's, and Toronto have given excellent service. Published reports by Wilson, Cooke, James, Mawdsley, L. V. Bell, and J. J. O'Neill greatly facilitated the work. For adequate control surveys and a topographic base-map, the writers are greatly indebted to H. N. Spence.

Jan 1, 1937

By J. S. Stewart

THIS paper was prompted by a persistent demand for what information we have that will throw light on the oil and gas possibilities of the Maritime Provinces. The problems involved were made familiar to the writer during three seasons of field work in New Brunswick and Nova Scotia. The reasons for renewed interest are: (1) In many parts of that region, the surface is underlain by a thick series of unaltered sedimentary rocks. (2) Oil seepages occur, and oil in commercial quantity has been exploited' near Moncton, New Brunswick, for many years. (3) In recent years, a new method of attack has been developed toward the finding of stratigraphic traps. This method is based on a detailed study of the geological history of the region, as revealed in surface outcrops and samples from deep wells. The well samples show the lateral variation of strata, far from any possible surface outcrop of the same beds. Sufficient work has now been done in the Maritime Provinces to reveal the broad features of the geological history and the character and distribution of the various rock formations. Comparatively little deep drilling has been done in this region, but the holes are widely scattered and the samples from them have added much to the information obtained from the numerous outcrops of bed-rock. The following discussion gives a summary of available information that has a bearing on the subject.

Jan 1, 1943

"RésuméDans la première partie de cet article on discute Ie mode d'écail age aetueJJement en usage dans des mines souterraines. Par la suite, on presente la problematique d'écaillage à l’aide de barres conventionnelles et on discute les plus recénts développements des outils d'ecaillage portatifs et mécanisés ainsi que les techniques de détection des roches branlantes. Plus tard, on analyse la tâche d'écaillage avec des barres conventionnelles. Dans les chapitres qui suivent on présente un concept d'un outil d'écaillage portatif et mécanisé développe à l'Université Laval, ainsi que les résultats des essais de cet outil, effectués dans quelques mines au Québec. On constate que Ie nouvel outil d'écaillage démontre un potentieJ intéressant tant au niveau de l'effort requis pour effectuer la tâche d'écaillage que de la sécurité des mineurs.On conclut que l’application de cet outil fera un pas important sur Ia voie d'amélioration des conditions de travail dans les exploitations souterraines, tout en assuarnt une qualité accrue de l'écaillage.AbstractThe first part of this paper discusses the type of scaling operations presently in use in underground mines and derma; a scaling factor which is expressed as the:: area necessary to scale to extract one ton of ore. Subsequently, the problems associated with conventional scaling methods are discussed as well as recent developments in mechanized hand-held scaling devices and methods of loose detection. The elements of the scaling process are further analyzed. In subsequent sections of this paper, the conception and design of a mechanized scaling device, developed at Universite Laval is described. The results of field tests conducted in Quebec hard rock mines are presented. The experimental findings show that the mechanized hand-held scaling device shows great potential in improving the productivity and safety of underground mining operations."

Jan 1, 1995

By Karl J. C. Harries

13.1. RIGHT TO RECEIVE ROYALTY CONTRACTUAL ONLY1

Jan 1, 2003

ABSTRACT The SART (sulphidization, acidification, recycle, and thickening) process is an effective way to separate copper and cyanide in the waste stream of gold processing plants using cyanidation. Factorial experimentation has been conducted to create models of copper recovery, cyanide recovery, acid addition, and oxidation/reduction potential during SART. Economic analysis of the resultant models showed that SART is best operated with a sulphide-to-copper molar ratio of approximately 0.56, pH of 4, and a minimized cyanide-to-copper molar ratio. The experiments also showed th0at residence time can have drastic impacts on SART performance.

Jan 1, 2013

By J. Jankovic

Numerous advantages have been recognized for solid oxide fuel cells (SOFCs) operating at temperatures of 500-700°C. However, there are several issues related to low temperature SOFCs, such as high electrolyte resistance and high electrode polarization. One of the routes to enhance the electrode performance, particularly for the cathode, is to use new materials with optimized microstructure. In this work, the plasma-spraying technique, recognized to have several advantages over presently used deposition techniques, was used to deposit cathode materials onto ceramic and stainless steel substrates to obtain highly porous structures. Cathode materials with composition of Lao 6Sr0.4Co02Fe0 8O3 (LSCF) were employed in the powder form. The LSCF was prepared from powder precursors with different pore formers and binder levels, or from already produced, single-phase LSCF. The (La0.8Sr0.2)0.98MnO3 (LSM) cathode material was also processed for comparison purposes. The deposition process was developed to obtain coatings with good bond strength, porosity, film thickness and residual stresses. The phase and microstructure of deposited materials were characterized using XRD and SEM.

Jan 1, 2005

By C. L. Popp

The scope is to address issues confronted by parties in the mining industry such as: Mine planners, survey and engineering departments, field teams and subcontractors. Describing approaches and best practices for assembling a project team to identify and create modeling requirements and to implement beneficial results. 3D Machine Control and Guidance tools continue to reduce project risk and attract quality resources with skill sets new to the earthmoving industry. These tools increase production, reduce rework and help with government permitting.

May 1, 2013

By The Mill Staff

Introduction The Hollinger cyanidation mill commenced operating in June, 1912, and 49,779,978 tons of solids had been discarded by the end of 1950. The present tailing disposal plant has been in operation since 1924 and holds 39,762,250 tons. The tailing disposal plant is on the property of Kayorum Gold Mines, Limited, about a mile and a quarter south of the mill. The area available for tailing covers 640 acres and is roughly l ¼ miles long by ¾ mile wide. Tailing was first deposited on the McKay veteran claims, l mile long by 1/2 mile wide, which were later included in the Kayorum property. This site sloped from northeast to southwest, the slope amounting to 106 feet between the northeast corner and the low land to the southwest. The low land was wet and a considerable area was covered with muskeg up to 17 feet deep. It was drained by a brook running across the property in a southwesterly direction. Later, when more ground was needed, the low-lying mining claims adjacent to the south and west boundaries were acquired to allow for the extension of the plant. This entailed some extra difficulties and expense that would not have been encountered had the whole of the present site been acquired with the original purchase. At the present time, the top of the tailing deposit stands at two elevations, but eventually the tailing deposited on the extension to the original plant will be raised to the same height as the older deposit. Previous to 1924, all of the tailing was deposited on Low land and in lakes near the mil1. Between 1924 and 1926 an increasing tonnage was sent to the McKay claims until, in 1926, all of it was being sent there. In 1936, the area of the deposit was extended and shortly afterwards all of the tailing was deposited on the new site.

Jan 1, 1951