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By Ken Wood, Luc Duval

"The development and operation of the milling circuits treating the different Selbaie orebodies are discussed in this paper. The project is reviewed from metallurgical evaluation through construction to present operating status. The current flowsheets are described, with discussion of some unusual features.IntroductionThe Selbaie concentrator commenced initial production in August 1981, treating underground B zone copper ore in a single 1500 t/d circuit. Throughput was increased to 1650 t/d in 1985. The mill was expanded in 1986 to treat ore from the A-I zone open pit; an independent circuit was added to selectively treat 5000 t/d of copper-zinc ore. Current total mill throughput through both circuits averages 7200 t/d with the production of approximately 270 t/d of copper concentrate and 230 t/d of zinc concentrate.This paper describes the stages involved in bringing the project from initial laboratory testing to its current status as one of the most important producers of silver, copper and zinc in Quebec and a major employer in the region."

Jan 1, 1990

By Daniel McConvey

Who is the Investor? -Mainly institutional, including resource funds, other mutual funds and pension funds. -Some hedge funds. -Retail investors. -How important is the reserve disclosure to these investors? -Do these investors know the difference between a reserve and a resource?

Jan 1, 2003

By C. O. Beale

This paper is the first part of a two-part review on the subject. , , .. Here reference is made to the place of copper among the elements, Its properties, Its historical significance, and its 'end uses both in general and in South Africa. Its current market situation and its prospects are dealt with briefly. Some account is then given of the mining and metallurgical techniques employed. in South Africa in the production of copper, together with the names of the companies at present Involved and brief descriptions of their operations, ,... . .. The operations of these companies are described In greater detail In Part 11(Apn11985 Issue of the Journal).

Jan 1, 1985

By Maurício Guimarães Bergerman

O objetivo deste estudo é apresentar a construção de uma coluna de flotação piloto de baixo custo, que será utilizada para concentração de minerais ferrosos. O trabalho contém os passos seguidos no projeto de construção do equipamento (descrição dos sistemas operacionais; dimensionamento; desenhos do projeto; levantamento dos materiais, fornecedores e orçamentos; testes dos sistemas de aeração e bombeamento, além da montagem) e também, os resultados dos ensaios exploratórios realizados com uma amostra de minério de ferro, contendo 38% de Fe, doada pela Companhia Vale S. A. proveniente da Mina de Alegria, Mariana/MG. Nos ensaios preliminares, obtiveram-se teores de Fe no concentrado próximos a 50% e uma recuperação metalúrgica em torno de 90%. O resultado foi considerado adequado, tendo em vista que foi realizado apenas um estágio de concentração. Dessa forma, conclui-se que a montagem e operação da coluna foram satisfatórias e o protótipo pode ser utilizado como unidade piloto para a avaliação de diferentes condições de processo.

Aug 1, 2018

By E. W. Lithgow, E. G. Williams, R. R. Holbrook, B. R. Wilson

The mineralogy and geochemistry of Pennsylvanian shales and underclays were studied to determine their suitability for lightweight aggregate and refractory ladle brick. Eighty percent of the variation in bloating of shales and clays was explained by the variation of Si02, A1203, and fluxes (Fe203, MgO, CaO, Na20, and K20); 60% by variation in quartz, kaolinite, illite, and chlorite. The best bloating was exhibited by marine shales, whereas freshwater shales and underclays experienced little or no expansion. Regional paleogeographic maps o f Pottsville and Allegheny shales permit bloating to be geographically predicted. It was found that clays meeting the specifications for refractory ladle bricks were obtained from underclays having over 34.5% mica, over 40% kaolinite and less than 15% quartz. Underclays of this composition are confined to the lower Allegheney outcropping along the near-margins of the coal basin. The best clay is that underlying the Lower Kittanning coal. Porosity of the first fired brick was found to be inversely correlated with reheat expansion.

Jan 1, 1975

By Antonio Martin, Jesus Hurtado, Francisco Jimenez

"Atlantic Copper is one of the largest copper producers in Europe. Its production facilities, including a primary copper smelter and an electrolytic refinery, are located in Huelva, on the southwest coast of Spain. These installations enable the smelting of over 1 million tpy concentrates to produce up to 260,000 tons per year of cathodes and 900 ktpy of sulphuric acid.Since 1970, several improvements have been made at the Converters Area such as modifications of primary hoods, operations with an OPC system, installation of scrap chargers, the recent installation of the secondary hoods and other environmental projects. All these modifications have been aimed at increasing the capacity of our smelter while keeping our continuous environmental commitment.This paper describes the modifications and improvements carried out at the converters area and our proposals for future developments."

Jan 1, 2012

By Ta M. Li

US mine-related fatalities were reduced by 10.3% at metal and nonmetal operations in 1974, according to a report by the Secretary of the Interior to Congress concerning the administration of Public Law 89-577. While there was no significant change in the overall injury experience, the 157 fatalities were the lowest recorded in the mining industry since federal mine inspections began under the Act in 1970. The report attributes this reduction to the "improvement in the quality and increased size of the inspection force as well as the continuing emphasis on mine safety conditions and practices." The year 1974 represents the first full calendar year in which the Mining Enforcement and Safety Administration (MESA) had responsibility for administration of the Federal Metal and Nonmetallic Mine Safety Act, and the Federal Coal Mine Health and Safety Act of 1969. Prior to MESA's establishment in 1973, these functions were delegated to the US Bureau of Mines. Research activities in health and safety were continued by the Bureau in 1974.

Jan 12, 1975

By David B. Reger

The expansion of the previously discovered gas pools and an intensified search for additional pools in the Oriskany and deeper sands were the principal petroleum activities in West Virginia during 1941. One small oil pool was discovered and another was considerably extended. One small gas pool was discovered, several isolated well discoveries were expanded into definite pools, and various recognized pools were substantially increased. The proved oil territory of the state was increased about 600 acres and the proved gas territory about 45,000 acres. The new discoveries of oil did not equal withdrawals but gas reserves added were greater than gas withdrawals. Oil activity, as in the past several years, was slight because of unfavorable crude prices. Most operators prefer to leave oil in the ground rather than to drill for it without a better return. Gas activity increased greatly because of better demand, even though the price of gas did not improve. The account of operations, as gathered from trade journals and other reporting services, shows that 838 new wells were drilled, resulting in 114 new oil wells with 2606 bbl. of daily new production; 558 new gas wells with 949,226,000 cu. ft. of daily open flow; and 166 dry holes. Also, 86 old wells were drilled to deeper sands with 9 bbl. and 56,030,000 cu. ft. of added production. On the new wells the oil average was 22.86 bbl. per well per day; and the gas average was 1,701,000 cu. ft. per well per day. On new wells the ratio of dry holes to completions was 13.61 per cent. On deeper drilling to other sands the ratio of failures was 15.12 per cent. From an exploratory standpoint one strictly new oil pool (Higginbotham Run) was opened in Kanawha County and one strictly new gas pool (Lost Run) in Taylor County. One entirely isolated wildcat gave commercial Oriskany-sand gas production and may open a pool. Various other wildcats greatly extended the boundaries of known Oriskany-sand gas pools and various others may have opened new pools in the shallow sands. On the other hand, various Oriskany tests in Harrison, Monongalia, Roane and Wood Counties were dry and all five tests to the White Clinton sand (Sil.) in Boone, Harrison, Kanawha and Wood Counties failed to find commercial production. The principal oil wells completed, by counties, were: Calhoun, 24; Clay, 7; Gilmer, 6; Hancock, 9; Kanawha, 9; Pleasants, 10; and Ritchie, 14. Production for the year was estimated by the Oil Weekly as 3,421,000 bbl., compared with U. S. Bureau of Mines final figures of 3,444,000 bbl. in 1940. The leading counties in gas-well completions were: Boone, 32; Braxton, 19; Cabell, 16; Calhoun, 46; Clay, 20; Gilmer, 37; Jackson, 94; Kanawha, 82; Lincoln, 17; Putnam, 46; Ritchie, 33; Upshur, 20; and Wayne, 33. Production for the year is estimated by the author as 210,000,000,000 cu. ft., as compared to the U. S. Bureau of Mines' final figures of 188,751,000,000 cu. ft.* in 1940.

Jan 1, 1942

By David B. Reger

The expansion of the previously discovered gas pools and an intensified search for additional pools in the Oriskany and deeper sands were the principal petroleum activities in West Virginia during 1941. One small oil pool was discovered and another was considerably extended. One small gas pool was discovered, several isolated well discoveries were expanded into definite pools, and various recognized pools were substantially increased. The proved oil territory of the state was increased about 600 acres and the proved gas territory about 45,000 acres. The new discoveries of oil did not equal withdrawals but gas reserves added were greater than gas withdrawals. Oil activity, as in the past several years, was slight because of unfavorable crude prices. Most operators prefer to leave oil in the ground rather than to drill for it without a better return. Gas activity increased greatly because of better demand, even though the price of gas did not improve. The account of operations, as gathered from trade journals and other reporting services, shows that 838 new wells were drilled, resulting in 114 new oil wells with 2606 bbl. of daily new production; 558 new gas wells with 949,226,000 cu. ft. of daily open flow; and 166 dry holes. Also, 86 old wells were drilled to deeper sands with 9 bbl. and 56,030,000 cu. ft. of added production. On the new wells the oil average was 22.86 bbl. per well per day; and the gas average was 1,701,000 cu. ft. per well per day. On new wells the ratio of dry holes to completions was 13.61 per cent. On deeper drilling to other sands the ratio of failures was 15.12 per cent. From an exploratory standpoint one strictly new oil pool (Higginbotham Run) was opened in Kanawha County and one strictly new gas pool (Lost Run) in Taylor County. One entirely isolated wildcat gave commercial Oriskany-sand gas production and may open a pool. Various other wildcats greatly extended the boundaries of known Oriskany-sand gas pools and various others may have opened new pools in the shallow sands. On the other hand, various Oriskany tests in Harrison, Monongalia, Roane and Wood Counties were dry and all five tests to the White Clinton sand (Sil.) in Boone, Harrison, Kanawha and Wood Counties failed to find commercial production. The principal oil wells completed, by counties, were: Calhoun, 24; Clay, 7; Gilmer, 6; Hancock, 9; Kanawha, 9; Pleasants, 10; and Ritchie, 14. Production for the year was estimated by the Oil Weekly as 3,421,000 bbl., compared with U. S. Bureau of Mines final figures of 3,444,000 bbl. in 1940. The leading counties in gas-well completions were: Boone, 32; Braxton, 19; Cabell, 16; Calhoun, 46; Clay, 20; Gilmer, 37; Jackson, 94; Kanawha, 82; Lincoln, 17; Putnam, 46; Ritchie, 33; Upshur, 20; and Wayne, 33. Production for the year is estimated by the author as 210,000,000,000 cu. ft., as compared to the U. S. Bureau of Mines' final figures of 188,751,000,000 cu. ft.* in 1940.

Jan 1, 1942

By James Howe

EVERY engineer and user of wire rope is desirous of information that will enable him to determine whether the performance of any particular piece of rope is satisfactory, and what conditions can be changed so as to increase the life of a rope. In most cases, it is far from easy to analyze the conditions of service and tell which is the greatest factor in determining the life of wire rope. If we start on a layout for an entirely new rope system, the task of making conditions satisfactory is simplified so far as the engineering details are concerned; but if the plant requiring wire rope is in operation, any change is likely to involve the expenditure of consider-, able money to replace and change over machinery that must be kept in constant operation, because a large monetary loss will result from a shutdown for even a few days. Often wire rope is kept operating under bad conditions, as the user thinks that it is cheaper and quicker to replace the rope than to make alterations in the hoisting machinery. A typical case is a metal mine operating in what is now almost the center of a large mining city, where it owns a few acres of mineral rights. It was expected that the shaft would go to a depth of 1000 ft. (305 m.), so a moderate sized rope, about 1 ¼ in. (31.7 mm.), was used on a 6-ft. drum with a 7-ft. head-frame sheave and rather short lead from drum to head sheave. This mine has gone deeper each year until, it is now 2500 ft. deep and the rope speed has been increased from 1500 ft. per min. to over 3000 ft. The original rope just filled the drum in one layer, now it overwinds three layers. The original ropes were probably 6 X 19 crucible steel and lasted from 12 to 18 mo.; now, the highest grade plow steel is used, yet the average service is only about 6 mo. The cause is not hard to find. If the engineers had known at the outset what would be done with this hoist, the design would have been very different. Conditions at this mine, from a wire rope standpoint, have gradually become worse and it is difficult to see how rope service on this hoist can be com-pared with the service of previous years with any fairness to the wire-

Jan 2, 1922

By Z. Botha

Sheryl Sandberg, the COO of Facebook, published a book titled 'Lean In', where she invites women to sit at the table. In summary, to 'sit at the table' entails not only embracing opportunity, but to actively seek out opportunities in leadership positions. Sandberg points out that, unfortunately, apart from institutional obstacles, a woman's own perceived limitations have a negative impact on her leadership ambitions. To create an environment where diversity will flourish, where everyone has a seat at the table and everyone has a voice, safety must be established first. To establish safety within a diverse team, there is power in relationships and connections. This study will first and foremost review theories in literature as to why diversity and inclusion are so important and the value that diversity brings to our industry. The study also recommends a few focus areas for improving diversity and inclusion in the industry.

Sep 1, 2022

By P .. D. Vaillancourt, D. F. Sangster

Several occurrences of disseminated galena, including a former producing mine, are found in Pennsylvanian fluviatile sandstone of the Salmon River Basin, Cape Breton Island, Nova Scotia. Detailed study of the distribution of these occurrences has revealed that highest galena concentrations are found in sandstone overlying channel-shaped depressions in felsic basement rocks. These buried depressions, in turn, correlate in position with modern streams in areas of basement exposure. This correspondence suggests that the latter are at least partially controlled by an exhumed Pennsylvanian topography. If this is correct, then several other streams in the area, lying on basement, may be used to locate possible undiscovered lead deposits in sandstones of the Salmon River Basin.

Jan 1, 1990

By Claus Becker

At the RETC 1979 in Atlanta/Georgia it was reported about the beginnings of the Hydroshield system and the first site experiences. Since that time over 10 miles of tunnels in various diameters have been built with that system, and the discussion of the two most interesting projects will be the main topics of this paper. AURELIA TUNNEL, ROME In Rome, the railway system is going to be completed and modernized. Therefore, it is necessary to tunnel through the Roman hills. Part of the new railway system is the Aurelia Tunnel, located some 100 feet below the famous Via Aurelia Antigua, close to the Vatican. The double track railway tunnel has an internal diameter of 9.44 m and a length of 2.410 m. It runs through completely differing soil conditions. (Fig. 1) The first 1000 t are situated in watertight clay, the rear part in water bearing loamy, clayey sands with interlayers of loamy clays. The figure shows the soft change-over from clay to sand. The groundwater head is between [ ]

Jan 1, 1983

The disadvantages of the present zinc producing methods, RLE and ISP, are high energy consumption and environmental problems. Therefore, efforts have been directed in Outokumpu Zinc towards the development of alternate routes. One interesting pyrometallurgical process to produce zinc is to inject zinc calcine together with a solid reductant into molten iron, saturated with carbon. This process has been studied by thermodynamic calculations, laboratory tests and mini-pilot test runs at Outokumpu Research Oy, Pori, Finland. The results of these tests are presented and discussed in this paper. The mini-pilot tests demonstrated that over 97 per cent evaporation of the zinc was possible using a reactive coal dust as the reducing agent. The recovery of zinc in the metal phase was at best 88 per cent of input zinc, but only part reported in molten lead in the splash condenser. The final metallic zinc contained at best 98 per cent Zn, the main impurities being dissolved lead and coal carried along with the flue dusts.

Jan 1, 1993

By H. R. Deeth, C. J. Koenig

About ten years ago nepheline syenite was introduced to the ceramic industry and the material has now found application in the various branches of the industry, namely, as a vitrifying agent in white-wares and as a source of alumina and alkalies in glasses, glazes, and porcelain enamels. Spencel described the early mining and processing developments regarding this material. Since the time of his article many research papers have appeared relating to the usage of nepheline syenite but little has been published relative to subsequent mining and processing methods. A complete indexed review of the literature was issued recently by Ohio State University.2 Since "Lakefield" nepheline syenite from Blue Mountain, Ontario (Fig I); is the only commercial ceramic-grade nepheline syenite now being marketed on this continent, discussion is limited to this operation carried on by American Nepheline Limited, Lakefield, Ont., and its subsidiary in the United States, American Nepheline Cory. at Rochester, N. Y. The Deposit Blue Mountain is a long ridge rising to an elevation of about 350 ft at its highest point above the surrounding country and extending for about six miles in a northeasterly direction across Methuen township, Peterborough County. The rock of the Blue Mountain central alkaline intrusive is fine grained, light colored and of even granitic texture. The solidified mass consists predominately of the minerals albite, nepheline and microcline in order of abundance. The average mineralogical composition for the deposit obtained by a study of 112 samples taken regularly over the whole formation is as follows:3 Volumetric Mineral Per Cent Albite.................... 54 Microcline................ 20 Nepheline................ 22 Muscovite................ 2 Mafics.................... 2 (Biotite, hastingsite, magnetite) Total................... loo The mineral nepheline (or nephelite) belongs to the feldspathoid group but is lower in silica content than are the feldspars. It is a silicate of soda, potash, and alumina (NaKAl2O32SiO2). Its presence with albite (Na2oA12O3 6SiO2) and microcline (K2O A12O3 6SiO2) gives the Blue Mountain deposit an alkali content of 15 pct and an alumina content of approximately 24 pct. While this huge alkaline mass is somewhat variable mineralogically, it has a uniform chemical composition. When the iron, mostly in the form of magnetite, is removed during processing, a remarkably uniform finished product is obtained. Geological surveying has disclosed many million tons of nepheline syenite in the Blue Mountain deposit. Diamond drilling in the area where mining is now being carried out indicates a block of about one million tons.

Jan 1, 1949

Improve the dust-control effectiveness of the Rotoclone1 dry-dust collection systems used on surface coal mine drills.

Jan 1, 1994

By Gunther F. Leichtle, James A. Finch, Colin A. Hardie, Cesar O. Gomez

"The recycling of wastepaper has become an important and common process worldwide. Techniques similar to those used in the mineral processing industry are used to produce high quality recycled fibers for use in newsprint. The mineral processing group at McGill University in conjunction with the Pulp and Paper industry (Mechanical and Chemi-mechanical Wood Pulp Network) has adapted one of these techniques, column flotation, for the purpose of deinking wastepaper. This article describes the typical process of recycling wastepaper from a mineral processing point of view. It also presents results from McGill University's flotation column test work at a Quebec wastepaper recycling facility.IntroductionThe recycling of wastepaper has become an important and common process worldwide, including Canada which is now the world's largest importer of wastepaper (CPPA, 1996). Much of the current drive to increase the utilization rate of recovered paper is a reaction to the solid-waste disposal problem that faces many Canadian and U.S. municipalities. The real problem in the disposal of solid waste is not the absolute amount of garbage that must be disposed of each year but this amount in relation to available disposal capacity.Environmental restrictions on the creation of new landfill sites and incinerators (the two main options for disposal of municipal solid waste) have tightened the demand/supply balance in the solid waste disposal market. This shrinking availability of waste disposal sites in the face of increasing population with greater disposal requirements defines the Developed World's solid waste crisis. Not only are there fewer disposal sites available, but the costs of using them is skyrocketing. These factors have increased government regulations mandating recycled paper content in newsprint. Conservation and environmental issues make the current drive for wastepaper recycling a real issue and business opportunity.A key to the success of producing quality recycled fibers from wastepaper is the deinking technology. The production of tissue papers, paper towels and newsprint requires regenerated fibers which are substantially free of ink particles. Of the various options available, mineral processing techniques can offer the most economical, environmentally acceptable and versatile strategies (Yoon, 1993). Today, it is recognized that flotation is one of the most effective processes for removing ink particles in the production of a high quality product. In a collaborative program with the Pulp and Paper industry, the mineral processing group at McGill University has adapted column flotation technology for this purpose. This article will describe the typical process of deinking from a mineral processing point of view (Part A). It will also present some results from McGill University's flotation column test work at a nearby paper recycling facility (Part 8)."

Jan 1, 1998

By J. D. Braun, C. W. Powell

Diffusion between gold and indium at two temperatures below the melting point of indium (155.4oC) was investigated. The major, component of the diffusion zone was determined to be AuIn2; the other, intermediate phases in the system occur in much narrower layers In order of decreasing layer width these are: Au9In4, AuIn, Au4In. Inter diffusion coefficients of the four intermediate phases and the terminal solid solutions lie in the range of 2.4 x 10-l3 to 1.8 x 10-11 sq cm per sec. WHEN two metals which do not form a continuous series of solid solutions interdiffuse, each phase in equilibrium at the diffusion temperature should appear as a separate layer in the diffusion zone. In the Au-In system, diffusion plays a significant part in many commercial applications, particularly where indium alloys are used as solders for electrical contacts with very fine gold wire, for estab- lishing electrical contact to thin metallic films, and for mounting metal-coated piezoelectric crystals. A knowledge of the number, extent, and type of phases which form at diffusion temperatures below the melting point of indium, 155.4oC,1 and the diffusion constants for the system would be useful for these practical applications. Of more basic significance, additional information on polyphase diffusion in a system not previously investigated would be gained. The phase relationships in the Au-In system were determined primarily by Kubaschewski and Weibke1 and are based on thermal, microscopic, and X-ray analysis, Fig. 1. There are five intermediate phases in the system having approximate compositions corresponding to the formulas: Au4ln (ß)—80.0 at. pet Au; Au3In (?)— 75.0 at. pet Au; Au9In4 (d)—69.2 at. pet Au; AuIn—50.0 at. pet Au; AuIn2—33.3 at. pet Au. Solid solubility of indium in gold at 700°C is reported as 12.64 at. pet and at 406°C as 10.36 at. pet. No solid solubility of gold in indium is reported.

Jan 1, 1964

By M. Bourassa, R. del Villar, S. St. Arnaud, J. Valenzuela

"Autogenous grinding is used quite frequently for mineral comminution as a result of its lower capital and operating costs. However, it is more difficult to control than conventional grinding, particularly when the autogenous or semiautogenous mill is the only comminution stage (i.e. no secondary grinding is available). Analysis of the control strategy used then becomes extremely important, a task that is greatly simplified by the use of an empirical dynamic simulator:This paper presents the methodology used in the development and the calibration of such a simulator for the autogenous grinding circuit of an iron are concentrator: The various steps are described: industrial data acquisition, preliminary treatment of the gathered information. and empirical modelling of the process. Finally, both the actual and the proposed control strategies are compared using simulation results.This exercise has shown that the variability of some of the controlled variables could be reduced through a better handling of the water addition and the use of filters on some of the signals used for control purposes. The reduction in variability of critical variables, such as power draw, would allow their average value to be increased without the risk of exceeding their safety values. Some advanced control techniques were also tested, with interesting results."

Jan 1, 1995

By AIME AIME

FELIX E. WORMSER was born in Santa Barbara on Oct. 31,1894, so is one of the youngest members of the Board, only H. D. Wilde t 39) and W. M. Peirce (43) being his juniors. After graduating from the Columbia School of Mines as an E.M. in 1912, he went West and worked for the Snake River Mines, the Baker Mines Co., and the Cornucopia Mines CO., all in Oregon. Then for a year or two he was the youngest U. S. Mineral Surveyor in Oregon. In 1918 he was in the Army from which he was honorably discharged as a Second Lieutenant. Early in 1919 he joined the staff of the Bureau of Mines, at Washington, assisting in compiling reports and in War Minerals Relief work. His acquaintance there with J. E. Spurr led to his joining the staff of the Engineering and Mining Journal as assistant editor in April, 1920. He specialized in market studies and assisted in the compilation of the Journal's metal quotations until June, 1925, when he resigned to engage in active mining examination and consulting' work in the Northwest for H. H. Armstead. Three years later he returned to New York at the time of the formation of the Lead Indus- tries Association, becoming its Secretary and Treasurer, a position that he has since held.

Jan 1, 1940