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By S. Thorley

In engineering design of operator?s compartments, in underground mining equipment, ergonomics principles are often neglected or not given the full recognition they deserve. This paper defines ergonomics, applies it to machinery in an underground mining environment and describes the ergonomics analysis undertaken during the design phase of an EJC extra-low-profile mining loader. Encompassing the design of the operator?s compartment of this new loader, this paper illustrates the importance of ergonomics principles within the collective design process, ensuring that it is fully integrated into the design approach. An ultimate aim of this study is to ensure that all future designs follow this route to guarantee not only the outcome of a highly efficient, cost-effective and productive machine but that it is also takes the human factor into account, not only in maintenance but also in operation. Maximizing comfort will have the ultimate outcome of actually increasing productivity.

Jan 1, 2006

By R. O. Dannenberg

The Bureau of Mines conducted laboratory batch and small-scale continuous tests to remove traces of dissolved molybdenum from water simulating waste discharged from a molybdenum concentrator, Molybdenum concentrations, initially ranging from 2 to 10 ppm, were decreased to 0.5 ppm or less by coprecipitation of the molybdenum with freshly precipitated ferric hydroxide" The precipitate was separated as a froth by dissolved-air flotation for subsequent disposal. Although the treated water met current environmental standards for contained molybdenum, contained particulate iron might have to be removed by filtration for the water to be acceptable. Estimated costs for treating concentrator effluent water were 55 cents, 57 cents, and 64 cents per 1,000 gal at initial molybdenum concentrations of 2, 4, and 10 ppm, respectively.

Jan 1, 1982

By B. S. Van Gosen

In recent years, U.S. regulatory agencies have placed emphasis on identifying and regulating asbestos dust exposures in the mining environment, with a particular focus upon industrial mineral deposits in which asbestos occurs as an accessory mineral. Because asbestos minerals form in specific geologic environments, only certain predictable types of industrial mineral deposits can potentially host asbestos mineralization. By applying a basic knowledge of asbestos geology, the costly and time consuming efforts of asbestos monitoring and analyses can be directed towards those mineral deposit types most likely to contain asbestos mineralogy, while saving efforts on the mineral deposits that are unlikely to contain asbestos. While the vast majority of industrial mineral deposits in the Western United States are asbestos-free, there are several types that can, in some instances, host asbestos mineralization, or be closely associated with it. These industrial mineral deposits include a few types of aggregate, dimension, and decorative stone, and some deposits of chromite-nickel, magnesite, nepheline syenite, olivine, rare earth elements, talc, vermiculite, and wollastonite.

Jan 1, 2009

By Frederic M. Langevin

?? Introduction ?? LaRonde ?? History of Seismicity and Rockbursting ?? November 27th 2002 Rockburst ?? April 1st 2006 Rockburst ?? December 11th 2006 & January 11th 2007 Rockbursts ?? Seismic Risk Management Plan ?? Conclusions ?? Located in Northwestern Quebec (Can.) ?? In operation since 1988 ?? Reserves at Shafts #1 and #2 depleted ?? Production now comes entirely from Penna Shaft ?? Deepest single-lift shaft in the western hemisphere (2240 metres) ?? 7300+ tonnes per day ?? 2007 Reserves (proven & probable): ?? By-products: Ag, Cu, Zn ?? Sinking #4 Shaft (LaRonde II winze)

Feb 1, 2008

By Albert L. Toenges

[sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we. sing tho ppsf; few Yomn t!le:.c. hcs beer. p. trqnd away frorn locomotive haulwe of cop2 frorn tile losdiw point to tho prop,nration plant of bitu~i- nnus-cod strip mlncc to a;~to~lzcd. h,71Jlr.:~. The qrostion has arisen rrhethcr this is alwqvs econ~nicd, rxcl the purpcrse or' tnf s investigation is to de- termine, if possible, the econonic limlt for ~~torieod had.we.]

Jan 1, 1938

By E. Simode

El presente texto describe los métodos de medida y ventilación aplicados a las labores de subterráneos. En este sentido, los elementos fundamentales de tales estudios son las resistencias de los circuitos, que se determinarán a partir de medidas de pérdidas de cargas y de caudales. La calidad de dichas medidas es condición para el éxito del método, dado que en ellas residen las causas de numerosos errores. Entre los aparatos de medida tenemos: la medida de los caudales, velocidad, secciones y las presiones. Los métodos de medida son: medida de los caudales, medidas de las pérdidas de carga, expresión de la resistencia de un elemento, esquematización de los circuitos,.

Sep 1, 1962

By Marcello Rodrigues Cruz

O presente estudo objetivou avaliar as diferenças no processo de flotação entre as frações -0,150 +0,038 mm e -0,038 mm, bem como a redução de custo no processo de flotação. Verificou-se que as frações apresentam resultados bem distintos em recuperação mássica, recuperação metalúrgica, seletividade, razão de enriquecimento e teor de sílica no concentrado, condições ideais de adição de reagentes e qualidade final de concentrado e rejeito entre as frações e também se comparada a ao experimento controle, composto com a mesma amostra sem ser fracionada. Através dos testes executados segundo o planejamento fatorial, foram estabelecidos os pares de variáveis ótimas para a flotação para cada fração distinta e as possíveis otimizações utilizando-se a ferramenta estatística. Os resultados obtidos dos testes de bancada apontaram que a amostra composta e as frações separadas apresentam comportamentos distintos quanto às variações dos fatores dosagem de amina, dosagem de amido e pH de flotação e que os resultados do processo melhoram significativamente em relação ao processo sem o tratamento fracionado.

Aug 1, 2018

By Manuela Arend Prediger

Este trabalho tem como objetivo investigar, através da Espectroscopia UV-Vis, os diferentes estados de oxidação da Polianilina (PAni) obtida pela síntese química, através da reação da anilina em meio ácido e persulfato de amônio como agente oxidante, sob agitação constante e baixa temperatura. A caracterização da condutividade elétrica foi determinada através da técnica de medidas de 4 pontas. Foi possível verificar a obtenção de um polímero com características condutoras, através da observação, nos Espectros UV-Vis, dos picos que caracterizam o sal esmeraldina, sendo este o estado de oxidação da PAni que apresenta propriedades condutoras. Além disso, conseguiu-se obter valores de condutividade elétrica relevantes para confirmar a obtenção da PAni condutora.

Aug 17, 2017

By Stanley K. Haines

This Bureau of Mines publication comprises 19 tables of data concerning domestic barite production and consumption, imports, and world production for the years 1880 to 1976. Barite is vital to the petroleum industry, with 90 percent of domestic consumption used in drilling muds. Domestic production has traditionally fallen short of consumption: in 1976, 41 percent of the 2.2 million tons consumed was imported. World production of barite increased from 269,000 tons in 1923 to 5.2 million tons in 1975 but is in danger of falling short of future demand. The compiled data provide a comprehensive base of information.

Jan 1, 1978

By J. W. Thompson

MEANING OF TERM, The term "minerals" when used in grants or in reservations or instruments of conveyance is not limited to metals or metalliferous deposits, whether contained in veins that have well-defined walls or in beds or deposits that are irregular and are found at or near the surface or otherwise. Byron v. Utah Copper Co., Utah, 178 Pacific 53, p. 58. The term "mineral" in its commercial sense has been defined as any organic substance found in nature having sufficient value sepa- rate from its situs as part of the earth to be mined, quarried, or dug for its own sake or its own specific use. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., - W. Va., 97 South- eastern 684, p. 685. CONSTRUCTION AND MEANING. It can not be said that the term "minerals" includes only such substances as are procured by tunnelling and shafting, as much gold is procured by placer mining and rich deposits of manganese and other like ores are found upon the surface of the earth and are some- times obtained without either quarrying or mining. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., W. Va. ——, 97 South- eastern 684, p. 685. GRANITE AS MINERAL. It has been determined that granite was included in a grant of minerals. Rockhouse Fork Land Co. v. Raleigh Brick & Tile Co., -W. Va., 97 South eastern 684, p. 685. See Armstrong v. Lake Champlain Granite Co., 147 N. Y. 495, 42 Northeastern 186.

Jan 1, 1919

By Brian T. Burch, Paul N. Worsey

When fired, submerged Linear Shaped Charges (LSCs) lose all effectiveness in the cutting of steel. Users in underwater applications have reported having to substantially increase the charge size to the point where brute explosive force shears rather than cuts the target.

Jan 1, 2015

"INTRODUCTIONGold tailings retreatment plants have been operated for many years throughout the world. Several large tailings retreatment facilities have been operated profitably in South Africa since 1976 and there are tailings retreatment operations in Canada currently in production with more in the feasibility stages.The Timmins Gold Tailings Project of ERG Resources Inc. was designed to treat 8,000,000 tonnes per annum of gold tailings for an eight month operating season, and commissioning of the operation began in July 1988. The payback period for this project is about 3 years which corresponds to an IRR of 30%.This report summarizes the metallurgical characteristics of the reclaim tailings, describes the process flowsheet which was developed to enable ERG to economically recover gold from the Timmins area tailings, and reviews commissioning activities."

Jan 1, 1989

By James J. Anderson

In this talk I will report on an effort to reassess the risk of pile driving to juvenile salmonids migrating through Puget Sound. The study was motivated by the concern of the construction industry that provisions restricting pile driving during the spring migration is resulting in an unbalanced burden to the industry. In simple terms the industry wants to know if some construction can be conducted in the spring without harming the juvenile fish. Fisheries agencies have agreed to reconsider their regulations in the context of additional studies. So, in this talk I will present some thoughts on risk assessment in general and the results of our study to assess the impact of pile driving on Snohomish River juvenile pink and chum salmon that migrate through the Navy Homeport construction site at Everett. The research, which is being carried out by the Fisheries Research Institute at the University of Washington, was planned and is supported in a joint effort including: the Washington Department Fisheries, National Marine Fisheries Services, U.S. Fish and Wildlife Service; General, Manson, and Hurlen construction companies, the Department of Transportation and a number of Puget Sound ports authorities. I will first briefly discuss the early life history of the juvenile salmon the regulations are designed to protect Second, I will outline the legal criteria required for risk regulation and some specific thoughts on how a reassessment of pile driving risk might be approached. With this basis I will report on our research and how it can be applied to a new risk assessment.

Jan 1, 1990

Cook Colliery currently mines in the Argo Seam, beneath old workings in an overlying seam. The Argo seam is up to 4.8 m thick and a continuous haulage system behind an ABM25 is used to develop first workings. Current partial secondary extraction utilises floor stripping and pocketing or sumping first working pillars on retreat. The following paper summarises this recent secondary extraction experience, particularly from a geotechnical perspective, but also considering production and ventilation issues. Outcomes and learnings are presented for mining in this challenging and close multi-seam environment. The sealed castor seam workings are within 20 m, and vary from unmined areas to large first working pillars, to partial extraction panels and full extraction panels. High stress remnant pillars and goaf-edges are notable mining considerations. The mining environment is further complicated by faulting, thrust zones and weak laminated roof.

Nov 25, 2010

By S. J. Davenport

The increased consumption and importation of fluorspar and cryolite (1)3/ in recent years, and especially the addition of fluorine compounds to drinking water in the United States, have aroused renewed interest in the properties of such compounds and possible health hazards incident to their use. It has been suggested that the issuance of a revision and elaboration of Information Circular 7311, The Hazards of Hydrogen Fluoride Poisoning in the Mineral and Allied Industries, which hay been out of print for some time, would be opportune. Fluorine minerals have been known since the Middle Ages. Fluorine was isolated in 1886 by Moisson (2).

Jan 1, 1954

By G. Naud, J. Robitaille, M. Buonvino, A. Veltmeyer, A. R. Laplante

"A B6 Falcon concentrator was tested on several systems: a synthetic magnetite-silica ore, a massive sulphide gold-copper ore, a fine gold-pyrite-silica flotation tail, and a high grade gold ore in a low sulphide gangue (cyclone overflow).The Falcon demonstrated its ability to achieve separation in all cases, but with varying degrees of success. For the magnetite-silica system, separation proceeds until the concentrate bed overloads, at a mass of 300 to 400 g of magnetite. Recovery increased with decreasing particle size, down to the 25-37 µm and in some cases even the -25 µm class. Bowl geometry (angle) and gangue size distribution were the most significant operating variables. Results with the massive sulphide ore were the poorest, with gold recoveries typically around 10 to 20% at very low upgrading ratios, 1: 1 to 5: I. Gold recovery from the fine flotation tail ranged from 30 to 70% at upgrading ratios of 5 to 15; actual plant application would require a continuous unit (Falcon C20). The high grade gold cyclone overflow yielded a wide range of gold recoveries, but a very consistent relationship between recovery and mass processed. A concentrate of 0.5% Au could be processed at a recovery of 50%.The paper also presents results of a C20 application to recover fine iron from a magnetic tail. The unit is capable of recovering approximately 70% of the fine liberated iron in a high density product, with modest upgrading below 105 µm, and virtually complete rejection of the + 300 µ m product."

Jan 1, 1993

Researchers from the National Institute for Occupational Safety and Health (NIOSH) are developing a coal pillar rib rating (CPRR) technique to measure the integrity of coal ribs. The CPRR characterizes the rib composition and evaluates its impact on the inherent stability of the coal ribs. The CPRR utilizes four parameters: rib homogeneity, bedding condition, face cleat orientation with respect to entry direction, and rib height. All these parameters are measurable in the field. A rib data collecting procedure and a simple sheet to calculate the CPRR were developed.

Jan 7, 2020

By Marco A. Vera

"This paper investigates the froth function in flotation and the associated upgrading process. Flotation literature has revealed that one of the main functions of the froth phase is the cleaning of bubble-particle aggregates by rejection of entrained material. The cleaning and transport processes across the froth phase exert straining forces on these aggregates on their way up to the froth surface. These forces will impact on the recovery of bubble-particle aggregates.The grade at the top of the froth (TOF) is a parameter related to the quality of particles collected by bubbles in the pulp zone (true flotation). It has recently been demonstrated that TOF corresponds to the maximum practically attainable grade described by the recovery-grade (or enrichment ratio) curve. TOF lumps all the processes experienced by the bubble-particle aggregates before reaching the launder concentrate. This paper describes a methodology for quantifying flotation performance by means of the top of the froth sample - a touch of froth.INTRODUCTIONFroth flotation may be the most important mineral processing technique, but its theory is complex and is not completely understood even though many aspects have been studied and reviewed (Teague, 1998; Wills, 1992).Two distinct particulate systems prevail in the flotation process: a pulp phase and a froth phase (Figure 1). The pulp zone had been studied extensively; however, it is only recently that techniques to measure the froth zone performance have been developed (Contini et al., 1988; Falutsu and Dobby, 1992; Feteris et al., 1987; Seaman, 2002; Vera et al., 1999b).Flotation involves a number of mass transfer processes, occurring in the pulp phase and the froth phase. The formation of the froth and its subsequent removal are considered to be two important steps of the process. Phenomena that occur in the froth phase are known to affect flotation performance significantly (Cutting et al., 1981).Because the froth has a high free surface energy (as a result of the extensive interfacial surface between liquid and air), it appears thermodynamically unstable. The foaming is a dynamic balance, as new bubbles are added continuously from the pulp, while others disappear from the top. Under steady-state conditions, the volumes of added and subtracted air are equal (Booth, 1953)."

Jan 1, 2003

By R. E. McElvain

"Hydraulic transportation of solids in suspension with water or other carriers, such as oil is becoming more practical as economic situations develop with respect to the railroads and other carriers. Of significant importance, is also the increased size of the major operations and the total impact of larg- er tonnages and more critical sources of supply.There are several means of imparting energy into the solids and directing the material down a pipeline, but the centrifugal pump is emerging as the most practical piece of equipment when considering relatively large flows and recent development. We can now handle relatively high densities without interruptions. This provides the mining and transportation fields a more economical means of lifting and transporting coal and other mineral products.Equipment & MethodsWarman International has developed several methods of alternate PDP against high heads. We have, at least for the present time, shelved our pump which uses clear water to slurry method and have placed our major emphasis on the full development of the centrifugal pump. I personally see several similarities on the alternate reciprocating devices as compared with the steam piston type engine versus steam turbines. The centrifugal pump comes into its most advantageous position at about 2000 GPM and can also show advantages by means of increased mobility, when driving tunnels and in other difficult operations when considering the total economic results. We now have some interesting d<:ta on one 5 mile raw silica sand line designed for pumping at 200-400 tons per h:mr. This is a separate subject on a ""simplified approach to slurry transport"" and paper has been prepared for the Hydrotransport 5 proceedings in Germany this Spring. Reference 1 may be of interest to those who want to delve into the subject further, and I also have some advance copies of this paper."

Jan 1, 1978

By U. Gorkhan Akkaya, N. Enver

Geographic information system (GIS) is one of the most accurate and useful tools to help decision – making for decision-makers. As to expert systems, it provides solutions to the problems faced by mimicking reasoning of the human experts. Blasting operations in mining include high risks for the vicinity of the operations. GIS having required mechanisms to take right decisions for the people who have to make right and precise decisions, while it is utilized as a integrated system with expert reasoning, is thought to be considered important tool that provides to take decisions with ease, and also to reduce the risks in the blasting operations. It is possible to find out both of the economic and optimum solutions to solve the various encountered problems in the mining activities such as blasting operations, only when GIS integrated expert systems is used. Managing the spatial data unified with expert reasoning is the one of the greatest advantages of the system. In the scope of the study, various scientific studies were investigated. The benefits of the system were figured out and the phases of a unified system were proposed in the blasting operations.

Jan 1, 2013