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By Brennan Lang

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

May 1, 2002

By Z. D. Hora

The major fluorite producer in British Columbia was the Rock Candy Mine, inactive since 1942. Other deposits of economic interest include the Rexspar deposit, in which fluorite is associated with uranium and rare earth mineralization, and the Eaglet and Liard River occurrences. THE former Rock Candy fluorite mine, located 26 km north of Grand Forks, is the only major past producer of fluorite in British Columbia. The deposit was in production from 1918 to 1929 and again in 1942; total output was about 36,000 tonnes with average grade between 22 and 32 per cent CaF2. The fluorite body occupies a steeply-dipping vein structure, approximately 175 m long and up to 12 m wide, in porphyritic syenite. The chief vein-filling minerals are quartz and fluorite with local small len ses of barite. Fluorite content decreases with depth and the deposit becomes silicified. The Rexspar (or Birch Island) fluorite deposit is located 130 km north of Kamloops. The deposit is complex with rare earth elements and high uranium values, but !1uorite mineralization forms an independent zone adjacent to the uranium orebodies. Fluorite is present as fine-grained impregnations and as breccia cement in strongly schistose or brecciated alkali feld spar porphyry. Reported reserves are 1,088,000 tonnes of 22 per cent CaF2 or 450,000 tonnes of 29 per cent CaF2. 268 Another potential deposit of fluorite is Eaglet, situated on the north side of Quesnel Lake. Fluorite occurs as a stock work with scattered veins and irregular lenses up to 20 centimetres wide and as impregnations in altered Proterozoic Kaza Group feld spathic gneiss over an area of 1,500 metres by 500 metres. To date (1983) approximately $2 million have been spent on the exploration of this property and reserves of 18.8 mimon tonnes grading 11.59 per cent CaF2 have been outlined . A group of significant occurrences is known from north of Liard River Hot Springs Park , where fluorite occurs in small zones up to 17 m thick along the interface between Middle Devonian Dunedin Formation limestone and Middle Devonian to Mississippian Besa River Formation argillite. Fluorite, associated with witherite, barytocalcite and barite, is present as replacement bodies, breccia fillings and minor veins.

Jan 1, 1984

By Claudeir Carvalho Silveira

Para produzir os aços bifásicos galvanizados com revestimento de Zn-Fe as tecnologias de galvanização foram adaptadas visando à produção de aços com alta resistência, resistentes à corrosão e boa conformabilidade. Desta forma, e considerando as deformações obtidas na estampagem tornou importante a caracterização em laboratório da influência do nível e do caminho de deformação na geração de trincas do revestimento com Zn-Fe aplicado a um aço bifásico. O presente trabalho avaliou o efeito dos caminhos de Deformação Uniaxial, Deformação Plana e Estiramento Biaxial Simétrico na evolução das trincas do revestimento Zinco-Ferro (Galvannealed-GA) e sua conectividade considerando o aço base Dual Phase 600. Foi observado que aumento da área composta por trincas ocorre com o aumento do nível de deformação para todos os caminhos avaliados. O Estiramento Biaxial Simétrico foi o caminho de deformação que mais influenciou no aumento da área com trincas na superfície do revestimento e na conexão destas trincas com o aço base. Isso ocorreu em função do estado de tensão (tração-tração) imposta à superfície e à seção dos revestimentos. Mesmo sendo observada a conectividade das trincas com o aço base não foi verificado visualmente defeitos de desplacamento do revestimento tais como Powdering e Flaking.

Aug 16, 2017

By Paola Icaza Palma

El presente texto describe la importancia de las relaciones entre las empresas mineras y las comunidades. En ese sentido, se busca que el relacionista comunitario se convierta en modelo del ámbito de desarrollo y participación como consecuencia de sus labores.

Apr 1, 2015

THE. extraordinary volume of work done in this period, and the multiplicity of subject matter, make a year-by-year historical account undesirable, if the account is not to be an assembly of unrelated fragments. We shall, instead, undertake to narrate the development in this period of each of the branches of the subject separately, hoping that their interrelations will be self-evident. There is a certain arbitrariness in the selection of subject matter in the following sections. The development of important engineering alloys-for example, high-speed steel-is disregarded, for it is the primary purpose of this account to relate the advances in ideas, the growth of the science of metals; other historical accounts relate these parallel advances. Nor are advances in techniques stressed, though occasionally the most important are noted; nor is the progress described in allied fields such as welding, cutting, etc.; for though these developments have very frequently made possible the advances herein related, they are far too numerous to recount in anything short of a ponderous volume. There is a more serious arbitrariness, however; it is not an easy matter to draw the boundaries of physical metallurgy, and some contiguous subjects have been omitted that perhaps should have been included, such as, for example, corrosion, gases in metals, the magnetic behavior of metals and alloys, and certain other fields in the physics of metals. REACTIONS IN ALLOYS--DIFFUSION Many of the reactions occurring in alloys proceed by the operation of the process of diffusion in the solid state: the annealing of mixed powders to form alloys, the homogenization of castings or forgings, the freezing of alloys, the treatment of clad metals, the loss

Jan 1, 1948

By Ben V. Petersen

Surveying is to tunneling, as a steering wheel is to a car—somewhat essential if you want to end up in the right place. The principles of tunnel surveying have remained unchanged since the first tunnels were constructed: To mathematically connect the selected start and end points of a tunnel and physically translate that alignment onto the ground. The alternative is just dead-reckoning and leaves the probably less than satisfying end results to chance. Today’s laser-guided tunnels often have to thread the needle through a maze of soil types, utilities, structural features and other underground considerations. Surveying makes it possible.

Jan 1, 2005

By G. S. Hume

TuRneR Valley, on the eastern edge of the foothills of Alberta, 35 miles southwest of Calgary, continues to be the major oil field in Canada. This field began production of gas and naphtha from the Mississipian (Madison) limestone in 1924, and until 1936 all wells were drilled for these products. At the end of 1938 there were 104 gas wells. In 1936 proof was found of a crude oil zone in the same horizon but lower on the west flank of the structure, which is a large fold cut off on the east side by an overthrust fault of great displacement. Since 1936 drilling has been done for the development of crude oil and at the end of 1938 there were 64 crude oil wells. On test through a 1-in. choke these flowed at the rate of 50,000 to 60,000 bbl. a day, but on production would not be expected to make this volume. The output has been prorated according to the capacity of the Prairie market. During the harvest season, when the demand for oil and oil products was at its maximum, the allowable production of Turner Valley was 28,363 bbl. per day. With the arrival of winter, this was cut to 11,500 bbl. per day but later was raised to 12,500 bbl. Production in 1937 from Turner Valley was 2,767,221 bbl., which was more than double that of the previous year. Production in 1938 was 6,691,075 bbl., which is considerably more than double that of 1937.

Jan 1, 1939

By G. S. Hume

TuRneR Valley, on the eastern edge of the foothills of Alberta, 35 miles southwest of Calgary, continues to be the major oil field in Canada. This field began production of gas and naphtha from the Mississipian (Madison) limestone in 1924, and until 1936 all wells were drilled for these products. At the end of 1938 there were 104 gas wells. In 1936 proof was found of a crude oil zone in the same horizon but lower on the west flank of the structure, which is a large fold cut off on the east side by an overthrust fault of great displacement. Since 1936 drilling has been done for the development of crude oil and at the end of 1938 there were 64 crude oil wells. On test through a 1-in. choke these flowed at the rate of 50,000 to 60,000 bbl. a day, but on production would not be expected to make this volume. The output has been prorated according to the capacity of the Prairie market. During the harvest season, when the demand for oil and oil products was at its maximum, the allowable production of Turner Valley was 28,363 bbl. per day. With the arrival of winter, this was cut to 11,500 bbl. per day but later was raised to 12,500 bbl. Production in 1937 from Turner Valley was 2,767,221 bbl., which was more than double that of the previous year. Production in 1938 was 6,691,075 bbl., which is considerably more than double that of 1937.

Jan 1, 1939

By A. S. W. Kurny, M. Z. Huq

Bangladesh ilmenite is partially altered, containing pseudorutile, rutile and haematite as well as the predominant ilmenite phase. A typical analysis is 39.45% TiO2, 24.19% FeO and 33.0% Fe2O3. Reduction of the ilmenite by charcoal was found to involve two major reactions: conversion of pseudorutile into ilmenite and rutile, and change of ilmenite into metallic iron and rutile. The first, which was much the faster reaction, was responsible for an initial increase in ilmenite content with reduction time at lower temperatures. Apart from these two major reactions, rutile was reduced to lower oxides at 1 100 degrees C with a consequent decrease in its XRD peak height

Jun 19, 1905

By H Thanasekaran, J Kohmuench, B Seaman

To achieve an efficient separation in the flotation process, valuable particles need to be selectively segregated from the gangue while utilising a minimum number of flotation stages. TodayÆs existing flotation technologies are effective for fine particle size classes; however, limitations due to particle buoyancy and bubble-particle detachment restrict the effectiveness of traditional flotation approaches on coarser particles. As a result, flotation circuits are generally configured to process only fine particle size classes in order to maximise recovery in the primary stages. Eriez has invented a novel flotation technology, the HydroFloat, which overcomes these limitations by carrying-out flotation in a dense, fluidised-bed medium allowing for the recovery of coarse particles (>0.250 mm). Over the last 15 years, this technology has been successfully applied to industrial minerals with several full-scale units installed to recover particles up to and exceeding 3 mm diameter in primary flotation circuits. This paper includes discussions on the history of this technology, process theory, existing applications, and a review of recent sulphide-based laboratory test work conducted for Newcrest mining and others. Benefits of this approach, such as improved recovery, low energy consumption and reduced reagent addition will also be reviewed.CITATION:Kohmuench, J, Thanasekaran, H and Seaman, B, 2013. Advances in coarse particle flotation - Copper and gold, in Proceedings MetPlant 2013 , pp 378-386 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By B. J. Scheiner

A ferrous chloride-oxygen leaching system was investigated by the Federal Bureau of Mines as a means of re-covering copper and silver from a sulfide concentrate that had been pretreated to remove a majority of the antimony. The pretreated concentrate contained Cu, Ag, Pb, Zn, Sb, and As. Parameters affecting metal extraction, such as temperature, pressure, amount of ferrous chloride, and initial hydrogen ion concentration, were studied. Copper extraction of 98 pct was achieved by leaching 4 hours at 40 pounds per?square inch gage (psig) and 1000 ?C. Copper was recovered from leach solutions by cementation with iron, and the resulting ferrous chloride was recycled. Leaching the residue with cyanide followed by electrowinning recovered 99.7 pct of the silver. Iron, Sb, As, Pb, and S reported to the tails.

Jan 1, 1978

By Rob Farnfield, Ben Williams, Ashley Haslett, Diane Cartledge

Major accidents that occur within our industry are often tragic and expensive, damaging reputation and threaten the livelihood of the business. There isn’t anything in them that can be seen as positive for those that experience them. They undertake what are usually very painful, detailed and time consuming investigations to discover how the incident occurred and what needs to be done in the future to prevent similar incidents occurring. Many admirably choose to share the lessons learnt through industry organizations such as SAFEX International so that we can all have the opportunity of preventing similar incidents from occurring within our own organizations.

Jan 1, 2016

By Carlos A. Ferreira, Betina Hansen, Marco A. S. Rodrigues, Marcela P. Proença

"Nowadays, the concern with the reduction of industrial pollution has motivated researchers to found out new technologies for treatment of industrial waste. The clean technologies, as electrodialysis, are capable of treating these residues, minimizing the impacts when they are discarded directly on the environment. Membranes of SPS/HIPS, PAniCSA/SPS/HIPS, SPAN/SPS/HIPS were developed using chemical mixture method. Membranes were characterized by Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA) and Scanning Electronic Microscopy (SEM). Membranes were submitted to electrical polarization and to electrodialysis at NaCl and KCl solutions, in order to determine ionic transport through the membranes. Results were compared with commercial membranes. The average percent extraction for Na+ ions obtained by membrane was beyond 20%.IntroductionThe high environmental impact caused by the galvanoplastic industries represents today a world concern(1). In the galvanoplasty, thin metallic layers are deposited on metallic surfaces(2) through chemical methods or electrochemical process. This industrial process presents some disadvantages that limit its utilization, as the generation of toxic effluents containing concentrations of heavy metals usually above the limits allowed for his release in receiving bodies(1), the production of galvanic sludge which is considered hazardous waste and that is very difficult to treat, beyond the high consumption of water (3).Stimulated by the development of new ion-exchanged membranes with high selectivity, lower electrical resistance, and improved thermal, chemical and mechanical properties, the use of electrodialysis in the wastewater treatment has recently gained a broader interest(5). The electrodialysis (ED) is a mass separation process in which electrically charged membranes and an electrical potential difference are used to separate ionic species from an aqueous solution(5). The technique permits the recovery and the reutilization of the waste products from the industrial process, avoiding the discharge of them on the environmental (acting as clean technology)."

Jan 1, 2008

By C. B. Auel

THE subject of this paper involves the crux of the industrial safety problem. It is not overstating the fact to say that "a plant can be made as safe as the management and the workers want it to be;" if such desire is not in evidence and it is not possible to maintain interest in the work of safety, there can be practically no headway beyond the first few steps. These first steps may be said to embrace simply the mechanical or equivalent guarding of tools and equipment and may be taken in a more or less perfunctory manner; but, it has been estimated, they will not effect a reduction of more than 25 to 35 per cent. in the accidents likely to occur in an unguarded plant. The question therefore may be pertinently asked, "Whose interest is meant in the title of this paper, employers', employees?, or both?" It has been repeatedly stated that no safety work of any importance can be carried on: in a plant unless the employer believes in the value of such work. Such statements are true, but have become threadbare with constant repetition and the public is led to believe, that employers differ from ordinary human beings, that their sympathy for their fellowmen has become dulled, and they can be awakened to a sense of the fitness of things with respect to safety, health, sanitation, working hours, etc. only by legislation. There will undoubtedly be found an employer, now and again, who measures down to such specification; but the speaker, in a number of years of close contact with large employers (and his experience has been duplicated by many others) has found that the employers are usually far in advance of the general public in matters affecting the welfare of their employees, including their safety, and not from a selfish viewpoint, but from the humanitarian, economic, etc. If, at times, there is an apparent lack of headway in the solution of some problem connected with employees' welfare, it is not so much due to indifference or a failure to be awake, on the part of the employer, as it is to a lack of knowledge of the way in which to proceed to its successful accomplishment. Further, employers are, only human and cannot follow. every one of the innumerable matters connected with an industry down to their minutest details; they must delegate certain individuals as their representatives, clothing them with the necessary authority to act. These representatives should be looked upon as the Management in their respective fields and the

Jan 6, 1925

By Wagner Luís Garcia Silveira

Nos últimos anos a thyssenkrupp Companhia Siderúrgica do Atlântico – CSA tem passado por uma série de mudanças no que diz respeito ao perfil de qualidade das matérias-primas, principalmente em relação à piora de qualidade do minério de ferro extraído do quadrilátero ferrífero em Minas Gerais, o qual compõe 100% da carga metálica utilizada pela CSA. Uma das principais mudanças observadas foi o aumento do teor de fósforo na carga metálica (sinter produto, pelota e granulado), tornando-se necessários estudos para minimizar os impactos na elevação de P no gusa, tais como, desenvolvimento de novos fundentes e aditivos. O fósforo é um elemento que traz poucas alterações nos processos de Metalurgia da Redução (Sinterização, Coqueria e Alto forno) e existem métodos eficazes de redução destas alterações [1], porém é extremamente prejudicial à qualidade, produtividade e custos de uma Aciaria, principalmente em produções de aços que exigem baixo teor de fósforo em sua composição [2]. Este trabalho tem como objetivo apresentar os esforços realizados pela Sinterização em relação à redução do teor de fósforo no Sinter Produto e consequentemente no Gusa, por meio de simulações de qualidade envolvendo novos fundentes e aditivos.

Aug 17, 2017

By M. M. Baube

El presente texto describe la evolución de la productividad minera francesa. En ese sentido, la producción de carbón en Francia, ha aumentado de más 20% en relación antes de la guerra, así como en las minas de hierro, el rendimiento "Fondo v Superficie" se ha duplicado de 1938 a 1959. Dicho progreso se extiende a los métodos de explotación, la maquinaria utilizada, electrificación, seguridad y la revalorización de los productos.

Mar 1, 1962

By Jacek Kolacz

A new sensor based sorting system related to complex image analysis has been developed at Comex AS - Norway. It makes it possible to separate different mineral particles regarding their color, shape, texture, size, density and indirectly their composition. The sorting system has been successfully tested and applied for sorting minerals providing high separation efficiency in the range of 95-99.9 %. The main advantage of this system is connected with its universality where many material parameters are analyzed in the same processing unit by a single passage.

Sep 1, 2012

By T. Bednarski, L. Thomas, G. Banza, D. Muteba, P. Cole, M. Soderstrom

"In copper solvent extraction, aqueous-in-organic entrainment results in the carry-over of unwanted species into the electrowinning process with negative cost implications. The need to bleed is increased and the purity of the copper cathode is potentially compromised, depending on the impurities being transferred (Cl, NO3, Fe, Mn). In some cases, entrainment results in elevated levels of manganese in the electrolyte which can cause oxidative conditions to develop and degradation of the organic phase. Degraded organic phase detrimentally affects the physical performance of the copper solvent extraction process, contributing to even higher aqueous-in-organic entrainment. Aqueous entrainment may be minimized through good operating practices and maintenance of the organic quality, but the accurate measurement of entrainment remains a challenge. This paper presents coalescing devices designed to provide more exact measurements of aqueous-in-organic entrainment. IntroductionMany copper solvent extraction (SX) plants experience high aqueous-in-organic (A-in-O) entrainments but are unaware of the extent of the problem because entrainment is often not measured. Aqueous entrainment results in the carry-over of unwanted species into the electrowinning (EW) process and the need to bleed to maintain acceptable concentrations in the electrolyte. The costs associated with the bleed are exacerbated in copper plants where aqueous entrainment levels are high. Other than these direct costs, there are operational consequences of the build-up of certain species in the EW circuit that can have deleterious effects on plant performance.Minimizing aqueous entrainment in operating plants requires an understanding of the factors that affect entrainment levels. Both chemical and operational influences are discussed in this paper. The difficulty of obtaining a representative sample makes it challenging to obtain an accurate measure of aqueous entrainment from a continuous process like SX. Coalescing devices used to get a more precise measurement of A-in-O entrainment are useful to complete mass balances around the SX circuits. Alternatively, mass balances can be used to estimate aqueous entrainments and are helpful as a tool to troubleshoot operations with a view to improving plant performance."

Jan 1, 2016

By R. A. Hodge, J. W. Murray

By an order of the Executive Council of the Provincial Government dated January 18, 1979, a Royal Commission was established under the Public Inquiries Act to: 1) Examine the adequacy of existing Federal and Provincial requirements for the protection of the health and safety of workers associated with exploration, mining and milling of uranium in B.C. and for the protection of the environment and of the public. 2) Receive public input on these matters. 3) Make recommendations for setting and maintaining standards for worker and public safety and for the protection of the environment as a result of the exploration for the mining and milling of uranium ores. At that time,and at the present time in British Columbia, no uranium mines were, or are, in operation. Exploration at a number of sites was under way and one deposit, the Blizzard deposit, with estimated reserves of 1.92 million tonnes containing approximately 4.74 million kilograms of U308 was at an advanced stage of exploration. With our Terms of Reference, and because of the diverse geology of the western Cordillera which could potentially host a broad variety of uranium, deposit types, the Commission was faced with the task of considering environmental and health protection necessary for the potential development of [any] kind of uranium mineralogy situated in [any] of the environments found in British Columbia. Over the past 17 months since that time, much has transpired, culminating in the February 27, 1980 Provincial Government announcement of a seven year moratorium on exploration, mining and processing of uranium coupled with the termination of our Inquiry before completion of the hearings. The Government sebsequently modified its decision to terminate the Commission completely, deciding instead to stop the hearing but allow time for the Commission to gather in the work that had been initiated

Jan 1, 1980

By Juan Francisco Retamozo

Hoy es indispensable que los profesionales de ingeniería de minas se capaciten en gestión y habilidades blandas, para responder adecuadamente a los nuevos retos que plantea el mercado laboral. Como producto de su extensa práctica como ingeniero de minas y coach personal en el sector, el autor desarrolla en este artículo diversos aspectos de interés para aquellos profesionales interesados en acceder a posiciones de liderazgo.

Aug 30, 2020