Search Documents

By F. H. Hueston, R. S. Barclay

"Depending on the application, zirconia, fused magnesia and graphite have been found to be the most suitable crucible materials for melting uranium metal and its alloys. Although graphite has been found to be satisfactory for uranium and uranium alloy castings with cross sections of 4 square inches or greater, ceramic-type molds are superior for small sections and those shaped castings which prohibit the economic use of machined graphite molds. Heating cycles, addition mechanisms and furnace conditions for melting are discussed."

Jan 1, 1967

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 H. M. Lima, L. A. Gomiero, C. A. de Morais

ABSTRACT The Caetité-Brazil uranium facility produces approximately 400 tonnes U3O8 per year from an ore averaging 0.29% U3O8. The process steps are ore crushing, heap leaching with sulphuric acid, uranium separation and purification by solvent extraction (SX) with a tertiary amine, followed by stripping with a sodium chloride solution, precipitation as ammonium diuranate (ADU), and product drying. A change in the milling process is being evaluated to increase production and uranium recovery. Heap leaching will be replaced by conventional agitated tank leaching of the –590 µm ground ore slurry in a sulphuric acid medium. Replacement of the stripping reagent is also being considered.

Jan 1, 2012

By Ross I. Kelly

Carbonate rocks are widespread throughout Ontario and provide raw material for more uses than perhaps any other rock type. The principal carbonate rocks that are used by industry in Ontario are Paleozoic era limestone and dolostone. Limestone is a sedimentary rock that is composed mainly of the mineral calcite (CaCO,) while dolostone, also a sedimentary rock, is composed mostly of dolomite [CaMg (CO,),l. The majority of the province's limestone and dolostone extraction occurs from Paleozoic era rocks located in southern Ontario. Calcite and dolomite are also found in Precambrian marbles, calcite veins and carbonatites, however, utilization of these rocks by industry has been less common. Calcite and dolomite-rich rocks are utilized for a wide variety of uses including raw materials for cement and lime manufacture, chemical and metallurgical stone, fillers and construction aggregates (Derry, Michener, Booth and Wahl and OGS 1989a). For some uses chemical and physical requirements are very important. In the manufacture of glass, for instance, the chemical requirements of source materials are very important and very stringent. In other uses physical criteria such as whiteness may be more important. Although carbonate rocks are quite plentiful within the province, deposits that contain high concentrations of calcite or dolomite are somewhat limited. For that reason, this paper focuses on deposits that are known to, or may contain, a high percentage of calcite and/or dolomite. The paper emphasizes potential sedimentary limestone and dolostone resources, as these are the carbonate rocks most commonly utilized by industry in Ontario.

Jan 1, 2001

By Corby G. Anderson, Caelen D. Anderson, Patrick R. Taylor

"The United States contains a variety of domestic rare earth element mineral sources containing such as ancylite, bastnasite, monazite, and xenotime. Research has been performed to investigate the fundamental surface chemistry involved in the froth flotation of these minerals, and apply the knowledge gained to substantiate the results through experimental testwork on a domestically sourced rare earth ore. This paper will outline the fundamentals and literature of rare earth mineral flotation, review its industrial applications and provide some recent research updates.THE RARE EARTH ELEMENTSRare earth elements (REE’s) are a unique family of elements with nearly identical physical and chemical properties. They account for approximately 1/6th of all naturally occurring elements, but the entire group occupies only one position on the periodic table. These 15 elements make up the lanthanide series (atomic numbers 57–71), and all but one (promethium) occur naturally. In addition to these 15 elements, yttrium and scandium are also considered rare earths since they tend to occur in the same deposits as the rare earths and share similar physical and chemical properties as seen in Figure 1. In particular Figure 2 denotes, a cartoon of the subtle differences in each caused by the 4f atomic sub shell (Gschneidner Jr., 1964). These subtle differences result in very difficult challenges in the selective concentration and final separation of each rare earth. (Anderson, 2015, Kronholm, Anderson, Taylor, 2013)Rare earths are separated into two different subsections; the “lights” or LREE’s (lanthanum57 through europium63) and the “heavies” or HREE’s (gadolinium64 through lutetium71). Yttrium is generally considered a heavy rare earth since its ionic radius is close to that of the HREE’s, while scandium is not considered either a light or a heavy."

Jan 1, 2016

By M. J. Latva-Kokko, T. J. Riihimäki

"Oxidation autoclaves are normally operated at elevated temperature and pressure. The improvement in kinetics is due to combined effect of temperature and partial pressure of oxygen. In this paper exclusive effect of pressure has been studied with a low grade sulphide ore at below 100 °C temperature. These studies are related to development of a novel tower-like reactor that utilizes hydrostatic pressure. Technology is designed to generate high amount of effective fluid volume for high solid content slurries with lower energy consumption and improved kinetics compared to normal atmospheric operation.INTRODUCTIONEconomical utilization of low-grade ores requires handling of enormous amount of material. This sets new requirements for process equipment in terms of size and energy efficiency. For example on the field of mineral processing this has lead to a six fold increase in the operating volume of mechanical flotation cells over the past two decades. Ore beneficiation methods like flotation greatly reduce amount of material that needs to be further processed in smelters or hydrometallurgical refineries. However with some ore types, such as nickel laterites and refractory gold ores, traditional concentration technologies cannot be utilized. Thus direct leaching of ground ore could be an attractive option. In many cases normal atmospheric tank leaching has traditionally been a non-feasible option mainly due to high capital and operational expenses induced by large amount of stirred reactors required. Main restriction for increasing reactor size to beyond 500 m3 has been mechanical load and power requirements set by mixing in cases when high dispersion efficiency of gas is required. THEORETICAL BACKGROUNDIn hydrometallurgical industry autoclaves are typically operated at elevated temperature and pressure. In many cases increase in operating temperature is the desired phenomena and improvements in kinetics are strongly related to that. Thus increase in pressure might be induced solely by water vapor pressure. However when gaseous feed is present, pressure itself has a strong effect on leaching kinetics for various reasons and its role should not be neglected."

Jan 1, 2012

By Z. Zhang

Aluminum boron carbide particulate reinforced composites have found new applications in nuclear industry due to their special capability to capture neutrons, Recently, Alcan successfully developed a liquid metal mixing process to fabricate Al¬B4C metal matrix composite instead of powder metallurgical technology. In the process, titanium is added into the composites to control interactions between boron carbide particulates and aluminum matrix, To understand the effects of titanium on the composites, the solidification microstructure of Al-16%B4C without or with titanium was examined by optical and electron microscopes. The results show that titanium can improve the uniformity of the particulate distribution within aluminum matrix if the titanium content in the composites is more than 0,5%, Furthermore, it is found that the layer with rich titanium on the surface of the particulates can limit the formation of AlB2 type compounds, which may greatly deteriorate the fluidity of the composites, In addition, it is also found that the amount of the reaction products in the composites increases with the increase of holding time. However, the rate of the increase is mitigated by the increase of the content of titanium in the composites. Besides, a procedure was proposed and implemented for the evaluation of uniformity of particulate distribution within aluminum matrix.

Jan 1, 2005

By Roy Sage

Overview ? History ? background to current programs ? Kyoto status ? Support for technology development ? Support for GHG reduction ? Sources of information History ? 1988 - Toronto Conference - The Changing Atmosphere ? Proposed target ? CO2 levels reduced to 20% of 1988 levels by the year 2005 ? 1992 - Canada signed Framework Convention on Climate Change at the UN Conference on Environment and Development in Rio de Janeiro in June 1992 ? Canada launched the National Action Plan on Climate Change ? Kyoto protocol adopted in principle in 1997

Nov 1, 2002

By Dennis Martin

What is Borehole Hoisting Borehole Hoisting is the use of a hoisting plant to hoist rock, workers and materials or both, vertically through a borehole, between a mine level and surface or between two levels of an underground mine. Screen and bolt ground support on walls of 5.5 m diameter borehole hoisting shaft

May 1, 2013

By A. Warczok

Smelting slags contain payable metals in a dissolved form and as mechanically entrained matte or metallic inclusions in the size range from 2 to 1000 µm. Slag cleaning requires reduction of magnetite and metal oxides and sedimentation of inclusions. Slag cleaning in an electric furnace is carried out in batch or semi-continuous mode. The strong trend for continuous slag cleaning generates the basic question about the optimal geometry of the electric furnace. Results of combined CFD, potential distribution and heat transfer modeling allowed for the determination of the fluid flow pattern and the temperature distribution in a classical, circular electric furnace as well as in a rectangular furnace. For the rectangular furnace, various length/width ratios and position of electrodes have been simulated. Analysis of key phenomena pointed out the advantages of the rectangular electric furnace over the circular furnace, particularly for continuous slag cleaning. Phenomena that have been analyzed were mass transfer, the rate of slag reduction, coalescence and settling of inclusions, all on the basis of the calculated slag flow pattern and the temperature distribution.

Jan 1, 2007

By R. Rumpold, J. Antrekowitsch

"The continued increase of the automobile production leads to a higher platinum, palladium and rhodium (PGM) demand. Due to the high value of the PGMs the recycle of these metals from automotive catalysts is of special interest. Pyrometallurgical processes, which are only focused on the PGMs, represent the state of the art of automotive catalysts recovery. However, hydrometallurgical recycling processes offer additional recovery of other valuable metals and compounds. The method presented in this paper is based on a combination of hydrochloric acid and hydrogen peroxide to dissolve the valuable metal fraction which can be precipitated afterwards.INTRODUCTIONPlatinum and the corresponding metals from the PGM group, especially palladium and rhodium are well known as catalytic active materials. They support chemical reactions which are inhibited. This effect is used to decrease the amount of harmful compounds like hydrocarbons, carbon monoxide or nitrogen oxides in automotive exhaust gases. The generation of these toxic substances is based on incomplete combustion, which in turn is caused by non-ideal conditions in the combustion chamber. Catalytic converters minimize the harmful compounds by supporting the following Reactions 1 – 3 (Votsmeier et al., 2009).CO + ½ O2 ? CO2 (1)CnHm + (n + ¼ m) O2 ? n CO2 + ½ m H2O (2)2 NO + 2 CO ? N2 + 2 CO2 (3)Platinum and palladium are very effective for the oxidation (Reactions 1 and 2), while rhodium supports the decomposition of nitrogen oxides by carbon monoxide (Votsmeier et al., 2009). The classical three way catalyst was a platinum – rhodium combination with a Pt:Rh ratio of 5:1 (Hagelüken et al., 2005). Today the platinum, palladium and rhodium ratio is highly variable and strongly depends on the engine type as well as on the car producer. Diesel engines are operated with a super stoichiometric air addition in comparison to spark ignition systems. Therefore the exhaust gas composition and off gas temperature is different. Based on the high oxygen amount, diesel engines produce less carbon monoxide and hydrocarbons but more nitrogen oxide in contrast to gasoline engines. This leads to various requirements for the catalytic converters."

Jan 1, 2012

By A. Oja, M. Lahtinen, P. Salonen, B. Saxen

Most of the secondary and low grade zinc raw materials cannot be treated successfully by either conventional roasting - leaching - electrowinning (RLE) process or even by atmospheric direct leaching process. The problems arising especially from high impurity content of these raw materials can be effectively solved by implementation of the solvent extraction process. The utilization of solvent extraction process has been demonstrated by Outotec with raw materials like Waelz oxide, crude zinc oxide and zinc containing concentrator tailings. Based on batch and continuous test work it has been shown that SHG quality zinc can be produced even from the lowest grade raw materials. Impurity control in the solvent extraction process has been examined. The solvent extraction process is the key feature of the whole zinc plant for such raw materials. However, design of the entire zinc process including neutralization and bleed treatment is important for optimization of investment and operation costs of the plant. Very careful evaluation of the zinc process with modern simulation tools is essential. The optimized Outotec zinc process ensures a sustainable and profitable process containing minimal effluent and requiring little residue treatment.

Jan 1, 2014

By W. A. Jones

Purpose of Paper Geophysics is a highly developed science which has found a wide use in industry. Perhaps the most spectacular application has been in the field of oil exploration. It has been estimated that, up to the end of 1939, geophysics was responsible for the discovery of five billion barrels of oil. In 1944, the sum o $40,000,000 was expended for geophysical work in the search for new oil deposits. Although the metal mining industry has so far made comparatively little use of the science, it is becoming increasingly common for the exploration engineer or geologist to be required to co-operate with the geophysicist. Many papers dealing with applied geophysics have been published but in most of them advanced training in physics and mathematics on the part of the reader has been assumed. It is difficult for the average engineer to obtain a ready understanding of the equipment, field procedure, and scope and limitations of the science from the literature. The present paper attempts to describe briefly and in simple terms the principles underlying magnetic, self-potential, and electrical resistivity methods and their application to a field problem. Introduction Geophysics is concerned with the study of gravity, magnetism, natural earth currents, earthquakes, vulcanism, and many other natural phenomena. The methods, originally devised for the measurement, for scientific purposes, of the forces associated with such phenomena have been adapted to the search for buried deposits of economic value. If the body sought has large dimensions and distinctive physical properties, geophysical measurements may reveal associated, and in some cases quite characteristic, anomalous features. However, in many instances the mass cannot be indicated directly but has a common association with geological features which can be defined by physical measurements. Although such surveys cannot specifically identify oil, metalliferous minerals, or other commercially valuable substances, it is possible to delineate anomalous sub-surface physical features which, with the help of geological information, can be assessed as possible or probable indications of the body or structure sought. The nature and extent of the material causing an anomaly, and its economic importance, can only be determined by further exploration, such as drilling.

Jan 1, 1947

By John A. Allan

Introduction There are times when meditation on the past is worth while. Too often does it happen that in the busy routine there appears t9 be little time for reflection, and little good or benefit to be derived from what has already taken place, or what has become past achievement. Under conditions such as those that prevail at present, consideration is being given to many subjects that a few years ago were not looked upon as worthy of time or thought. The temporary lull in industrial development is permitting of a stock-taking investigation, a perusal of past activities, and a planning for future development with the return to normality. It is not proposed to include much new data in this address, but the endeavour will be made to survey, in resume, the sequence of events which led up to the birth of the mining industry in Canada, and to show how, as new discoveries were made, the centres of interest changed from time to time until mineral development extended across Canada from the Atlantic to the Pacific. It will appear, also, that external causes have accentuated mineral development at one time and retarded it at another. Early Records A, historical background to the mining industry extends even to an earlier date than the discovery by white men of that part of the continent of North America represented by Canada. It has been stated that the aborigines were still in the neolithic stage when the white man arrived. One metal only was known to the natives, and that was copper, obtained from possibly many parts of Canada, but particularly from the shores of lake Superior in Ontario, from the Coppermine river on the Arctic coast, and from die coastal regions of British Columbia.

Jan 1, 1933

By C. Harold Riches

This article is directed co a commentary on the patent system in its relation to the public interest. As man gained supremacy over his environment, he could devote progressively increasing portions o his time to improving his standards of living. In the history of the human race, we have advanced from the hollowed floating log to the modern steamship of the present age; from the sickle and flail to the reaper and combine; from the trumpet and drum as a means of communication co the telegraph, telephone, and radio; from the horse and ox cart to the automobile, truck, aeroplane, and train; and so on ad infinitum through the list of inventions on which are based the industrial and political economies and standards of living we enjoy today. It has also been a long road from the day of the alchemist and his closely guarded secrets to the era of the patent system and its storehouses of knowledge open to the world. The alchemist and the craft and merchant guilds closely guarded their secrets. In fact, they largely opposed innovations on the grounds that they might injure profits and restrict employment. In these days of unrest, with great clamour out of doors for radical changes in our political and industrial economies, it may not be untimely to examine one of the keystones which support the economic structure we know as the free enterprise system, the system which is predicated upon the right of the individual to own property. Many, through impractical idealism, ignorance, confused thinking, or blind political prejudice, advocate the substitution of ownership by the State ? for the right of ownership by the individual. As civilization has advanced to the high standards of living we enjoy today through the efforts of a comparatively few inventors, the patent system which has provided the incentive that created the inventions on which our industries and our employment are based is fully understood and appreciated by a comparatively small percentage of our people. As a result, the patent system, as a keystone in our free enterprise economy, is an apt target for destructive criticism, with the thought, possibly, that by eliminating or drastically restricting the several rights to individual ownership one by one, ownership by the State will progressively replace ownership by the individual.

Jan 1, 1949

By Yuyong Li, Liangman Zhang, Zhaolian Wang, Shun Wang, Ltd. Shandong Huate Magnet Technology Co., Fengliang Liu

"Introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements. Adopting 240°-270° larger magnetic element with multi-poles and magnetic pulsation, and combining the devices of multi-channel rinsing water and top flushing water and new style tank, HUATE® JCTN can improve another 2%-10% concentrate mFe% than the traditional MS without lowering the concentrate recovery rate. Thereby, it solves the uneasy concentrate upgradation problem of the traditional MS resulting from the magnetic aggregation. Now, JCTN has been successfully applied in more than 30 mines in Australia, China and Russia, e.g. Sino Iron of CITIC PACIFIC MINING MANAGERMENT PTY LTD. HUATE® JCTN can optimize the industrial processing line by: 1) improving the discarding rate before milling to discard the necessary tailing ASAP; 2) getting in advance the final concentrate after milling. One JCTN can replace many traditional MS in series. In some way, it can also replace the anti-flotation separation process.INTRODUCTIONWe’re writing to introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements."

Jan 1, 2016

By R. D. Corrans

"Abstract - Africa is endowed with a number of the world's giant ore deposits which have contributed significantly to the development of their host countries. Mineral exploration has a long history in the continent, but mining on an unprecedented scale took off during the latter part of the 19th century, accompanied by the development of lines of communication and other infrastructure to service the major mining centres .The ""Winds of Change"" which swept Africa in the 1950s and 1960s brought in new styles of government and economic management to a number of regions, often with demise of economic viability and infrastructure. ln recent years, with the end of the cold war, collapse of communism and changes in South Africa, new opportunities for mineral exploration are opening up rapidly in Africa. However, due to the large cost, long lead-in time, and high risk of developing new mineral ventures in the continent, it is necessary for the host countries to draft realistic and favorable mineral laws and fiscal codes in order to attract, and not deter, potential mineral investors.There will be an on-going role in mineral exploration throughout Africa for the artisanal miner, the smaller entrepreneurs and mining companies, exploration aid programs funded by the developed countries through African governments, as well as the major mining houses who have the resources to develop larger viable mineral deposits."

Jan 1, 1994

By C. E. Dowker

"IntroductionMechanization underground at the Buffalo Ankerite mine in Deloro township, Porcupine district, had reached a high level by 1944, both in equipment available, and in the use of this equipment, for all stoping operations. Power feed leyners and the latest type of stopers for drilling, slushers for moving ore and fill, and tugger hoists for all servicing, did much to halt rising stope costs, and in some cases decreased them. On the other hand, little beyond the use of mucking machines and power feed leyners had been adopted in the effort to reduce level development costs, or to increase the advance per man-shift.Faced with ever increasing level development costs, caused by rising prices of equipment and supplies, coupled with increasing wage demands for less physical effort, it was realized that more mechanization of development work was essential. The objectives of such further mechanization were:(1) Decreased development costs(2) Increased footage per man-shift(3) Less physical effort by development crews, with greater take-home pay (4) A more satisfied and stable labour force"

Jan 1, 1950

By J. H. Hodgson

"Those of us who have been concerned with the problem of geophysical exploration in southwestern Ontario have followed the development of the Poulter method with much interest. I have much appreciated the opportunity of reading an advance copy of Dr. Poulter's clear exposition and of preparing the following brief remarks on the probable applicability of the method to the Palaeozoic area of southwestern Ontario.During the years 1944 to 1946, the Ontario Department of Mines, in co-operation with the Union Gas Company and the Dominion Natural Gas Company, operated an experimental party in the hope of establishing a seismic technique appropriate to the •area. The results were completely negative. During two summers' field work, no reflections whatever were obtained except in one area near Windsor. It is the •purpose of these remarks to inquire whether Dr. Poulter's techniques might yield favourable results.It was the conclusion of the report on our work that two principal causes contributed to the failure of the method. In the first place, the geological column possesses few elastic discontinuities and those that exist appear to have low reflection coefficients. In the second place, the area is drift-covered in general. This drift complicates the situation by absorbing seismic energy and by giving rise to groups of complicating refracted phases which obscure the entire interesting section of the record. The situation is further complicated by the high reflection velocities and the relative shortness of the Palaeozoic section, these factors combining to bring in a reflection from the basement in about half a second."

Jan 1, 1950

By Fred W. Snow

THE mines of the Consolidated Copper and Sulphur Company, consisting of the Eust1s, the Albert, and the Capel mines, are situated w Ascot township, Quebec, about ten miles southeast of Sherbrooke, on the main line of the Quebec Central railway. Of these mines, only the Eustis is now producing, and it has been operated almost continuously for the past seventy years. Mining methods have been improved in recent years but are still old fashioned when compared with those employed in more modern and up-to-date mines. The ore is of milling grade and is mined for its copper and sulphur con-tent. Silver is present in small quantity, together with a trace of gold. The ore is mined by the shrinkage stope method. Pillars are frequently left as supports for the hanging-wall to prevent serious dilution of the ore and are sometimes recovered after the ore is drawn from the stope. Occasionally, small blacks of ore in close proximity to the shaft are mined by a cut-and-fill method. HISTORY ALBERT AND CAPEL MINES: The Albert and the Capel mines, originally known as the Capelton mine, were discovered in 1863 by George Capel (1). By the end of 1866 the Albert shaft had been sunk to a depth of 121 feet on an incline of about 30 degrees where a vein five feet thick was encountered. In 1879, these mines passed into the hands of G. H. Nichols and Company, by whom they were operated practically continuously until 1907. When mining operations ceased in that year, the shafts had reached depths on the incline of approximately 2,300 feet and 1,000 feet, respectively. These mines have been allowed to cave and fill with water and have been inaccessible for many years.

Jan 1, 1936