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By Liming Yuan

A study of the ignition of non-fire-resistant hydraulic fluid sprays was conducted by the National Institute for Occupational Safety and Health. Both an open flame and a hot steel surface were used as the external heat sources. With the open flame as the heat source, the minimum oil temperature and minimum spray nozzle pressure that resulted in an ignition were measured. The effects of the distance between the open flame and the nozzle and the nozzle orifice diameter on the ignitability of the hydraulic fluid sprays were examined. With the hot surface as the heat source, the minimum surface ignition temperature was determined. The degree of oil atomization and the relative direction of oil injection with respect to the hot surface are discussed. The ignition of oil sprays from the impingement of oil jets onto a vertical surface was also investigated. Finally, the results are compared with those obtained for fire-resistant hydraulic fluids. Keywords: Ignition; hot surface; open flame; hydraulic fluid

Jan 1, 2006

By Eugene T. Sheridan

The 22d annual survey of the packaged-fuel industry by the Bureau of Mines, United States Department of the Interior, revealed that 26 plants in 8 States were in operation and reported production in 1956. The demand for packaged fuel in the United States has declined gradually since the end of World War II, and the number of operating plants has decreased from 70 in 1946 to 26 in 1956. Annual productive capacity of the industry has decreased also during this period, and the decrease in capacity was about proportional to the decrease in operating plants. Packaged-fuel plants are relatively small, and 85 percent of the active plants in 1956 had an annual capacity of less than 10,000 tons. The same situation prevailed in 1946, when 84 percent of the plants had a capacity of less than 10,000 tons. Total capacity for the 26 active plants in 1956 was 174,600 tons, an average of 6,715 tons per plant. Operating rates in 1956 were the highest since 1951, and the rate of production for the industry averaged 37 percent of capacity.

Jan 1, 1958

By Luis Vassallo

El presente trabajo señala los beneficios que pueden obtenerse de la adopción inteligente de una estrategia de colaboración electrónica que responda a las necesidades de este segmento y que proporcione soluciones de verdadero valor agregado. Así, el modelo monolítico que prevaleció por muchos años, donde cada empresa era propietaria de las licencias mineras, operadora, mantenedora, contratista, vendedora, embarcadora y financiera, está desapareciendo. En la cadena de valor del proceso minero intervienen más empresas, contribuyendo valores agregados específicos y especializando funciones. Este cambio demanda mayores flexibilidades de los sistemas de información que deben ser totalmente abiertos, y permitir el intercambio instantáneo de información que facilite reaccionar oportunamente a las diferentes variables de la operación. Por ello, la colaboración electrónica permite a la minería adaptarse a un mundo que está cambiando.

Aug 25, 2002

By A. Tylczak, C. Norman, C. Shook, S. Loif

"There are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes or malfunctioning equipment early, which allows problems to be corrected promptly.Sacré-Davey Engineering in Vancouver has performed over 50 Energy Management studies for various industries including: mining, pulp and paper, oil and gas, etc. Energy Management programs can be used to identify energy reduction opportunities, assess project feasibility, complete equipment selection trade-offs, as well as to monitor and manage energy costs. Benefits of energy management programs are reduced energy costs, reduced maintenance, and increased plant automation. Additionally, energy management can provide access to utility incentive funding and quantify savings which can greatly improve the return on investment of potential projects.Energy management studies are funded by many Utility programs across Canada. There are various programs available for existing plants energy audits, project feasibility studies, new plant design reviews and energy monitoring and targeting, etc. There are capital incentives available which can significantly reduce payback period.This paper discusses how energy management can be used to support mill/mine operations groups, maintenance programs, as well as expansion or green field projects. This paper will also provide an overview of Canadian Utility companies programs and how they can assist mining companies.IntroductionThere are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes and identify malfunctioning equipment early, which allows problems to be corrected promptly."

Jan 1, 2015

By K. A. Allison, D. R. Van Orden, R. J. Lee

Continuing analysis of environmental samples for asbestos content has resulted in the misidentification of non-asbestos amphibole particles as asbestos fibers. These errors have received wide publicity (such as in the asbestos-in-crayon story) and have caused unnecessary reformulation of products. The primary cause of these errors has been a poor understanding of mineralogy and analytical techniques among the many asbestos laboratories that arose following the passage of the AHERA regulations. Presented here is a procedure based on published data that can be used to correctly classify an elongated particle as asbestos or as non-asbestos.

Jan 1, 2005

By W. L. Connell, O&apos

The properties of some heavy liquids which can be used in sink-float separations are discussed with major emphasis being given to the halogenated hydrocarbons. Data are presented on density, viscosity, thermal characteristics and the effects of moisture and temperature on the corrosiveness of the liquids towards various materials of construction. The toxicity of these materials, the hazards involved in handling them, and the procedures for handling them safely are also discussed. True liquids have certain advantages over colloidal suspensions for sink-float separation of minerals which makes their use especially advantageous when close separations, fine particle sizes or water-soluble minerals are to be treated. For best separating results, the medium should have an easily controlled, uniform, stable density. Here, true liquids have the advantages of allowing closer control of density and of not requiring agitation to maintain a uniform den- sity in the equipment. Low viscosities are desired in a separating liquid so that rapid separations of fine material can be made. Many liquids have lower viscosities than the colloidal suspensions at operating gravities of 1.4 to 5.0. For economic reasons and to prevent contamination of the product, the separating medium must be easily and completely removed from the ore. Normally, true liquids must be more completely removed than the cheaper suspensions and thus cause more problems in this area. The fact that the medium should not react with the minerals, air, water or the common materials of construction limits the choice of liquids which can be used, but many are available which are sufficiently stable. A more serious objection to the use of true liquids is that many of them present a toxic hazard to operating personnel and users of the product. Most true liquids are toxic to some extent, but modem knowledge of toxicity allows us to recognize the hazards inherent in handling them and enables us to design around them. Three types of true liquids are available for this use: 1) Halogenated hydrocarbons cover the gravity range from 1.2 to 3.3. They are generally more volatile and less viscous than the other liquids.

Jan 1, 1963

By N. S. Yet

This paper shall present the design and construction of bored pile and diaphragm wall for the proposed MHA complex in Singapore. The work was carried out by L&M Foundation Specialist Pte Ltd and PWD Consultants Pte Ltd was the consultant for this project. A brief description of the project is first presented to illustrate the scope and scale of the work involved, which includes the construction of bored piles and diaphragm walls and installation of steel stanchions in the bored piles. This is followed by a description of the methodology used to analyse and design the wall and bored piles. As both towers in this project are supported on bored piled foundation and are constructed by top down construction method, the analysis of the wall has taken into consideration the sequence of work phase by phase and this was carried out by means of a commercial finite element program called CRISP. Modelling of the problem will be briefly described and the findings from the numerical analysis will be presented. This is followed by a description of the structural and geotechnical design aspects of bored piles. The paper shall then describe the difficulties encountered for this project and solution used to solve the problem. The subsoil condition will be described with special mention on the encounter of very strong granitic rock at depth above the maximum excavation level of the basement at certain locations, hence necessitating the drilling of rock for a considerable depth for both bored piles and diaphragm wall. At this juncture, the construction method used to drill through the rock will be briefly described. For construction of bored piles, penetration of rock was carried out by chiselling or drilling using reverse circulation rigs. For construction of diaphragm wall, it requires the employment of Bauer hard rock cutter which uses cutting wheels fitted with roller bits and are capable of excavating into granitic rock of compressive strengths more than 100 MPa.

Jan 1, 2000

Drill cores from Section 62, New Broken Hill Consolidated Ltd., were used to study the petrology of rocks associated with the zinc lode. The distribution of the rock types in relation to the lode structure was determined. The distribution of the gahnite-bearing rocks was shown to be only partly conformable with the structure.It was concluded that large scale metasomatism was not widespread, that the rocks associated with the lode (except, perhaps, the quartz-gahnite-garnet rocks) were formed by metamorphism of sediments, and that rocks and lode were contemporaneously metamorphosed.INTRODUCTIONThis investigation was undertaken in order to study the rock types associated with the zinc lode of the Broken Hill orebody, and their relationship to the structure of the ore horizons. The work was confined almost entirely to the laboratory, and is therefore limited in its scope. It is hoped, however, that the information gained may throw some new light on the genesis of the lode.Certain inferences which are drawn from this work are at variance with the ideas of a number of earlier workers.In particular, the idea of large scale metasomatism developing many of the rocks associated with the lode, especially those containing manganese, is questioned. On the contrary, the rocks associated with the lode are more simply explained as highly metamorphosed sediments, in some cases modified by water introduced from surrounding rocks into zones of strong folding and faulting. As a corollary, a metamorphicsedimentary origin for the lode material, either as a concentrated sulphide deposit, or somewhat disseminated...

Jan 1, 1961

By Albaharna O. T., Argyropoulos S. A.

"This paper describes the development and the implementation of process control in a variety of instruments used in metallurgical laboratories. These instruments are used for different research projects in extractive metallurgy. Hardware and software aspects for this implementation are described and analyzed. Extractive metallurgy applications where process control was .used are presented. IntroductionMicroprocessors are invading almost every area of our lives and are turning up in unexpected applications. A great deal of new equipment which is coming into the market have built- in microprocessor systems. Nevertheless, the area of upgrading existing processes has been slow to develop. There are a variety of reasons for this, and many of these are economic. One of the principal reasons, however, is the general reluctance on the part of many organizations to commit a strong effort to put this new technology into their existing processes.Microprocessor systems developed ""in lab"" are capable of not only measuring thermophysical events which are taking place in metallurgical furnaces, but simultaneously controlling these furnaces. In this paper software and hardware aspects in the implementation of microprocessor control for resistance and for induction furnaces are presented. In addition to this, metallurgical results are given from experiments where this furnace control was applied."

Jan 1, 1989

By David A. Monaghan

On January 14, 1974 a fire occurred in the 3 East mains of the Joanne Mine of Eastern Associated Coal Corp. in Rachel, West Virginia. The mine was evacuated without injury and sealed completely at the surface within 24 hours. It was decided by the coal company along with the U, S, Bureau of Mines, the West Virginia Bureau of Mints and MESA that remote sealing of the fire zone would be attempted. This report summarizes the remote sealing effort and those activities directly related to the remote sealing effort. This chapter provides a brief history of previous remote sealing attempts, a description of the recently developed remote sealing system and a description of the Joanne Mine operation as it related to and affected the remote sealing effort.

Jan 1, 1975

By William F. Daly, William H. Hansmire

Installation of initial tunnel support is often the most uncertain element of work in the design of, and a contractor bidding on, construction of a rock tunnel. The risks the construction contractor and owner assume are delineated to a great extent in the technical specifications portion of the contract documents. It is intended that this paper identify current practices for specifying initial tunnel support and the impacts each case has on the assignment of risks associated with providing the initial tunnel support. Examples of recently completed tunnel designs are given.

Jan 1, 1985

By Troy Holm, Matthew L. Fuller, Frederick H. Earnest

Virtual Reality Animation Of The Proposed El Dorado Mine In El Salvador Assists Regulators In Reviewing An EIA

Jan 1, 2005

G. R. Compton (Gold Mines of Kalgoorlie (Australia) Ltd., Fimiston, W. A.) : In congratulating Mr. Hooker upon his resume of Mr Parry's paper I have in mind the fact that he carried out the research into pipe pressures. Hydraulic filling as practised in Kalgoorlie has created world wide interest, with these pressures and percolation being vital points.Early in the 1950s, representatives of the Kolar field were conduGted over the local mines where stopes at depths below 2,000 ft were being filled. The problems of pipe pressures were their main consideration since depths of up to 10,000 ft were envisaged.Mr Krishnaiah and Mr Murthy from the same field are with us today and perhaps we may hear of their experiences with depths of 6,000 ft and long lateral lines.J. Holly (Lake View and Star Ltd., Fimiston, W.A.): There is one phase, which I would like to mention myself, that has been very evident in Kalgoorlie operations. That is, we do not get the percolation properties that are obtained on many other fields in the world, and our tendency here has been to assess the quality of our fill more by its settling rate, i.e. the rate at which we can draw off clear water at the surface of the filling levels, rather than the rate that this water percolates down through the fill before it consolidates.We are tending now to measure the quality of our fill as a settling rate rather than as a percolation rate.Americans talk about percolation rates being the important property: If anyone has any experience on operating with fills with different percolation rates, I think their views would be very interesting to the meeting art this stage. Mr ...

Jan 1, 1965

By John Wilson

"The unconformity beneath 75 per cent or over 6000 km2 of the Athabasca Basin in Alberta lies within economically exploitable depths. The basement beneath this unconformity consists of an extension of the Wylie Lake Pluton, locally faulted and containing areas of mylonitic rocks. While the rocks of the Wylie Lake Pluton are not promising host rocks for uranium ore deposits, the areas of mylonites, graphitic rocks and possible remnants of granitegneiss would bear closer examination. One area of maficmylonites shows a weathering zone enriched in Si, Ca, Na, Pb, Ni, Ba, Co, Sr, Zn and U in addition to reported values of 0.08 oz/ton gold. This zone occurs beneath 800 m to 900 m of Athabasca Group sediments, but similar rock types are present beneath much thinner cover elsewhere. Detailed geophysical exploration is required over the area of thinner Athabasca Group rocks to define more precisely the areas of promising basement rock type.IntroductionThe Athabasca Basin in Alberta has considerable economic potential which has not yet been realized. The geological setting is closely analogous to parts of the basin in Saskatchewan which host major uranium deposits. Recent advances in geophysical techniques have led to deposits being located in Saskatchewan below 600 m of cover. This means that the unconformity between the Athabasca Group and the basement lies at exploitable depths over 6000 km2 or 75 per cent of the Alberta portion of the basin. Much of this area was only cursorily examined almost a decade ago. In addition, Alberta's new Metallic Mineral Regulations have clarified the regulatory situation in the area, and opened up much land for exploration. This article is based on Wilson's (1985a) study of the Athabasca Group and Wilson's (1986) work on the basement and alteration beneath the Athabasca Group in Alberta."

Jan 1, 1987

By AIME AIME

T HE Institute of Metals Division and the Iron and Steel Division will meet jointly at the Stevens Hotel, Chicago, during the week of the American Metals Congress, Sept. 22-26. The Iron and Steel Di- vision of the American Society of Mechanical Engineers, the American Society for Steel Treating and the American Welding Society meet at the same time. but the sessions have been arranged to conflict as little as possible. A rich program of papers and plant visits has been arranged for the members and guests of the two Institute Divisions. The annual dinner and a pro- gram of entertainment are being arranged by the Woman's Auxiliary of the Chicago Section. Members are urged to register immediately up011 arrival and to make dinner and plant visit reservations at the same time.

Jan 1, 1930

By R. A. Reiley

Introduction Democratic countries are founded on the principle that all citizens have the right to participate in policy setting and decision-making processes. Citizen participation is especially evident in environmental issues and policies. In the United States, there are currently over 10,000 environmental organizations and new ones are being formed each year. Many of these organizations are formed on a watershed basis and are particularly concerned about the impact mining has on the environment. While the environmental issues vary from area to area, most concerns center around mining impacts related to subsidence, water pollution, and water diversion. Citizens have a number of avenues for participating in lawmaking that affects the mining industry. Some of these avenues include participation in litigation and citizen ballot initiatives. In addition, there are less formal methods of participation that include attending public meetings, commenting on agency rules or lobbying on specific legislation. The intent of this article is outline the various public participations mechanisms, highlight the latest legal developments that have affected mining industry through citizen participation, and briefly discuss emerging issues.

Jan 1, 2001

Selective Removal of Arsenic from Acid Mine Drainage Containing Ferrous Ion Using Sulfide Precipitation Method

Sep 13, 2010

By R. R. Sayers

The hazards connected with work under abnormal air conditions are becoming of increasing importance from a financial as well as a physiological stand- point, due to the extension of compensation laws to include diseases caused by dusts, toxic gases, and abnormal temperatures and humidities. The United States, with the excention of California, North Dakota, Wiscon- sin, Massachusetts, and Connecticut, is the only English-speaking country to-day where silicosis is not compensated.3 Cases of permenent total disability or death due to silicosis mar aprear in common-law courts, particularly in the States that have not recognized silicosis as an occupational disease for which compensation should be provided. Such cases have recently been tried in one State, according to a magazine editorial, not providing scheduled commensation for employees affected by silicosis, with results favorable to the claimant. Clearly established cases definitely linked with occupation as the cause may be expected to be recognized as deserving by juries and courts, and awards will be made. In one Atlantic Coast State, according to this editorial, 108 claims for silicosis, including 21 deaths therefrom, are said to have been filed against two small plants engaged in finely pulverizing quartz sand.

Sep 1, 1932

By Paul Voigt, Mike Hourn, Glenn Stieper

Sable Zinc Kabwe Limited ("Sable") is a base metal processing plant, two kilometres south of Kabwe Town in Central Province, Zambia. The region has a rich history in mining and minerals production, being a major lead and zinc producer from the 1900s up to the mid-1990s. In 2006, a copper plant was built at the Sable processing site to treat third-party copper and cobalt oxide ores and concentrates. The oxide leaching plant included whole ore leaching, solvent extraction and production of 8,000 tpa LME Grade A copper cathode. The plant was placed on care and maintenance in 2014, and Glencore Plc ("Glencore") took the opportunity to convert the plant using a minimal budget, to an Albion Process™ plant to treat local refractory copper concentrates unsuitable or uneconomic for smelting. The Albion Process™ plant comprises an M100 IsaMill™ operating in acidic conditions such that raffinate from the downstream process is recycled back to slurry the concentrate delivered to site thus maximising copper tenor in solution and reducing water consumption. The finely ground concentrate feeds an oxidative leaching plant using the existing stainless steel oxide leach reactors converted to Albion Process™ duty by fitting HyperSparge™ supersonic oxygen injectors and gas dispersing agitators. The leached slurry is then directed to the existing solid/liquid separation equipment, and the PLS is then sent to the existing SX/EW plant. The plant also allows for cobalt recovery from the raffinate. The plant was designed based on testwork on regional copper concentrates. The plant was designed to toll treat a range of concentrates, and so the design was flexible With the flexibility of the Albion Process™ being one of its distinct advantages, the plant was ideally suited for tolling regional concentrates. The plant was commissioned and ramped up in six weeks using low-grade Zambian copper concentrate, and produced exclusively LME Grade A copper with over 99% leach recovery in the Albion circuit. INTRODUCTION The Sable Zinc Kabwe Limited ("Sable") process plant is located 2 km south of Kabwe town and 140km north of Lusaka in Central Province, Zambia. In 1902, rich deposits of zinc and lead were discovered with mines and processing plants operating in and around the town until mid-1994. In 2000, the Kabwe Mine tailings dams were sold to Sable, a newly established company, as part of a purchase deal for other plots and facilities. Up until 2004, Sable produced zinc cathodes in an SX/EW plant treating wash plant tailing material. In 2004, Sable was acquired by the South African mining company Metorex Limited ("Metorex"), and in 2006 a copper/cobalt SX/EW plant was built to produce copper cathode from malachite ore supplied from the Democratic Republic of Congo. In 2011, Jinchuan Group International Resources Co. Ltd acquired Metorex and Sable was in turn sold to a subsidiary of Glencore Plc ("Glencore").

Jan 1, 2019

By K. Morin

"Silver and gold leaching by cyanidation is a well-known process used around the world. This reaction is often accompanied by the leaching of other species throughtout the cyanidation circuit that causes the diversion of cyanide towards non valuable by-products (SCN-, Cu(CN)x, Fe(CN)x, etc.). One of the detrimental impacts of the formation of these by-products is the precipitation of silver-cyanide complexes that occurs when cyanide concentration is too low. Without any extra-addition of free cyanide, the precipitated silver is lost and cannot be recovered causing an important economic loss. To overcome silver precipitation, cyanidation circuits are often operated at higher cyanide concentrations. Recently, COREM’s research team has been working on a technology to measure and control silver precipitation during the cyanidation process. Moreover, a methodology has been elaborated in order to evaluate threshold cyanide level which corresponds to the cyanide concentration at which silver starts to precipitate. This technology has been tested on site on a real cyanidation circuit at Agnico Eagle’s LaRonde mine."

Jan 1, 2014