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By McKendry J. B

Gretley Colliery is situated at Wallsend, a suburb of Newcastle in New South Wales and is owned and operated by the Newcastle Wallsend Coal Ccnpany, a wholly owned subsidiary of Peko Wallsend Limited. The mine has been an efficient bord and pillar producer by industry standards. However, its continued economic viability was threatened because the bulk of remaining reserves lie in more difficult mining conditions and are of poorer quality. Alternatives were examined to improve productivity and allow Gretley to become more competitive in the current difficult market Environment.

Jan 1, 1988

[Costs may be classified according to their source and behavior: Scale of aggregation - Total costs - Unit costs Time period for which the costs are charged - Product costs - Period costs Controllability and relevance for decision-making and control - Controllable costs - Noncontrollable costs - Sunkcosts - Opportunity costs Their basic source - Production costs (also termed manufacturing costs) - Nonproduction costs How the costs change with changes in activity - Fixed costs - Variable costs - Semivariable costs Traceability to individual units of production - Direct costs - Indirect costs Use in planning (budgeting) and subsequent control - Standard costs - Normal costs ]

Jan 1, 1999

By Alan Tordoir, Mark Roberts

The drill and blast process is a critical function within the production cycle which significantly impacts the ability of an operation to effectively meet its safety and production targets. Acknowledging that D&B design and reconciliation practices were conducted inconsistently across operations, a Group wide initiative was launched to embed a standardized design and reconciliation platform in line with the company’s Operating Model principles. A technical system was selected to deliver the digitalization of critical D&B information and enable ‘analyze and improve’ routines for design compliance monitoring and downstream productivity optimization.

Jan 1, 2019

Full aerodynamic design development of the proposed fans for the enlarged primary ventilation system at Mount Isa Mines Limited was initiated before tender specifications were prepared. Theoretical and analytical design studies were made of many possibilities to determine the optimum proposal. Major considerations were efficiency, simplicity, standardization, and mechanical feasibility. Model testing and experimental work covered blading design, inlet shape, diffuser and tail fairing dimensions, instrumentation requirements, ancl noise studies.Theoretical and predicted performance estimates were prepared for the three 20 ft diameter vertically mounted axial flow fans.

Jan 1, 1967

By Edward A. Mihok

This paper presents plant design and cost estimates for limestone treatment of acid mine water covering a wide range of quality and quantity conditions. The treatment process consists of limestone neutralization, aeration, solids settling, and concentration. The design criteria for the various operation functions are based on pilot plant performance, laboratory data, and established mine water treatment standards. Unit costs have been assumed and are related to general market prices and conditions. These estimates serve as preliminary indicators of what it would cost to construct and operate a mine water treatment plant.

Jan 1, 1970

Twelve years ago, Jeffrey Mining Machinery Division of Dresser Industries Inc. developed the 120H HELIMINER. This machine was the world's first fixed-drum continuous miner and soon became the standard among manufacturers of continuous miners throughout the mining machinery industry. This paper will first outline a brief history of continuous miner development, then discuss significant parameters which are essential to a successful continuous miner design, and finally describe a number of specific applications of Jeffrey continuous miners in a variety of materials, such as coal, potash, iron ore, and trona, around the world.

Jan 1, 1978

By Howard E. Parkinson

An environment monitoring and communication system has been installed in the Bruceton Mine, and research is under way to improve mine safety. Standard day-to-day mine communications are available, along with additional systems installed to permit experimentation with wireless radio, through-the-earth phones, along-the-roof paging, and mine face machinery communications. Research is continuing and the essential concepts for a dependable whole mine communication system, providing simple environment monitoring, improved day-to-day communications and post-disaster communications, will be demonstrated in a larger mine with about 900 feet of overburden.

By P. Sotiropoulos

In the framework of the Specific Programme: ?Promoting Competitive and Sustainable Growth? a detection system was designed and developed in order to provide an added value service beyond standard instrumentation. In the hydrocarbon industry it will be possible for the first time to detect in a pulse regime, two types of radiation emissions using a single device. This means that any saturation of hydrocarbons can be detected, irrespective of the degree of formation water mineralization, which is a major limitation on currently available neutron-gamma tools, where the formation water has a low mineralization.

Jan 1, 2006

By G. Lyman

The cross-belt sampler is a device that is very widely used even though it has not been ratified by the Standards associations. This paper is concerned with the bias testing of two cross-belt sampler designs against stopped belt samples and a cross-stream cutter at the belt end. The bias analysis is carried out using size distribution as the analyte and conventional t-testing and the Hotelling T squared test, which are compared for their effectiveness. The paper considers the issue of detectable bias and the statistical planning of bias tests.

Jan 1, 2009

By Askew J. E

All facets of current practices of cable dowelling at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited are re- viewed. This includes materials specific- ations, installation practices and design pro- cedures. Cable dowelling for cut and fill stoping, square set timber stoping, longhole open stoping and level reinforcement is considered. Installation is simple and can be mechanised to eliminate heavy lifting. Quality control is essential for optimum performance of the re- inforcement. Design patterns must consider the mining method, reinforcement economics, acceptable stability standards and mine production priorities.

Jan 1, 1977

By H. Evans

It is well known that iron-ore pellets are considered one of the best blast-furnace burden materials used today. The demand for pellets is demonstrated by the increase in pellet output from one million tons in 1955 to approximately 37 million tons in 1964. This growth continues as new plants are placed on-stream each year. The consumer generally specified (1) the acceptable content and range of chemical constituents, (2) a minimum strength determined by some standard testing procedure, (3) the size range of pellets, and (4) perhaps a measure of reducibility.

Jan 1, 1966

Twelve years ago, Jeffrey Mining Machinery Division of Dresser Industries Inc. developed the 120H HELIMINER. This machine was the world's first fixed-drum continuous miner and soon became the standard among manufacturers of continuous miners throughout the mining machinery industry. This paper will first outline a brief history of continuous miner development, then discuss significant parameters which are essential to a successful continuous miner design, and finally describe a number of specific applications of Jeffrey continuous miners in a variety of materials, such as coal, potash, iron ore, and trona, around the world.

Jan 1, 1978

By Alfred E. Hunt

Tars paper is suggested by the appointment on the part of the American Societies of Mechanical and of Civil Engineers of committees upon the subjects of " Standard Tests and Methods of Testing," and " Uniform Methods of Tests of Material used in Metallic Structures," respectively, and by a study of the report of one of these committees, and other papers. Moreover, the writer has had frequent occasion to hear the complahts of tnanufacturers who furnish structural material subject to specifications, that in the tests prescribed, the number of tests required, and the methods of making

Jan 1, 1892

By V. V. Geikhman

The paper updates the Plant experience in the development and implementation of an advanced environmentally friendly zinc production technology complying with the technological and economic level of producers in the world and the standards of maximum permissible gas emissions stipulated by the Russian legislation. General water recycling engineering allowed to ensure 95.6% water rotation level. All solid wastes formed during treating zinc concentrate are processed into marketable products or semiproducts and sold. As a result of implementing innovation techniques production at the Chelyabinsk Zinc Plant is non-waste.

Jan 1, 2006

By R. Steven Maxwell, Ulrich Petersen

Most minerals have experienced a slow hut perceptible decline in their annual primary production growth over the past hundred years. This decline is due to a combination of factors: (1) increased recycling; (2) exhaustion of the more accessible or higher grade ores; (3) partial substitution; (4) the more efficient use of materials; (5) progressive saturation of markets as living standards rise. Therefore, future demand for new mineral resources will probably be lower than anticipated. As the world population stabilizes, this slowdown in production growth will become even more pronounced.

Jan 1, 1979

By August J. Kwitowski

This Bureau of Mines report describes how the reinforcement mechanisms of untensioned, full-column resin bolts were determined during one underground study. Both axial and transverse shear loadings were identified for two instrumented resin bolts that replaced standard resin bolts in an opera-ting room-and-pillar mining section. The strain responses of resin bolt steel cores to local axial and transverse shear loadings are described. This information was obtained from laboratory testing of resin bolts installations; it was also used to analyze the data from the underground test.

Jan 1, 1980

By F Hungerford

"In-seam drilling has been undertaken for the past 30 years for gas drainage to reduce the risk ofoutburst and lower the concentrations of seam gas in the underground ventilation. The drillingpractices have reflected the standards of the times and have evolved with the development oftechnology and equipment and the needs to provide a safe environment underground. Earlypractice was to adapt equipment from other fields, but with changing emphasis, research anddevelopment by the coal industry has created specifi c equipment, technology and practices toaccurately place in-seam boreholes to provide efficient and effective gas drainage."

Jun 1, 2012

By Dave Thomas

?Uranium is a common trace metal at the earth?s surface, but these are amazing super-high grade (up to 25%) pods, veins and disseminated uraninite (UO2) near unconformities between Proterozoic siliciclastic red beds and metamorphic basement with graphitic metapelite and radiogenic granite. ?Pitchblende fills extensional features in reactivated fault zones and replaces matrix in sandstone ?One mining district in Canada ?the Athabasca Basin ->30 deposits /prospects -most in eastern ¼of basin -produces 1/3 of world?s U -employs northerners -VERY high tech -VERY high safety standards Unconformity-associated uranium depositsUnconformity-deposits

May 1, 2006

By Sunil Koppalkar, Guillaume Noel, Ahmed Bouajila, Makni Sami, Claude Gagnon

"Gold gravity recovery circuits utilizing enhanced gravity separators have become an integral part of many of the modern gold processing plants. Thus, efforts to improve the operating efficiency have been a topic of interest for metallurgists for many years. As part of this endeavour, a methodology to estimate the portion of gold in the ore that could be recovered by gravity separation (gravity recoverable gold or GRG) was developed at McGill University. It has been reported in the literature that the gold content estimated with this methodology is the theoretical maximum that is available for gravity recovery that could only be approached but never achieved. A comparison of GRG recovery obtained in the laboratory with the actual recovery in the plant shows that plants recover between one-third to two-thirds of the value predicted by the laboratory test.Research conducted at COREM shows that particle shape transformation during grinding is a major cause of the discrepancy (even though the bleed percent processed, the quality of cyclone classification and the operating conditions of the gravity separator also contribute to the difference). To analyze the gold particle shapes and their deportment, samples were collected from different streams of a grinding-gravity circuit in a gold plant and compared to a concentrate sample from the standard GRG test. A particle characterization methodology based on gold morphology was developed. GRG mapping in a conventional grinding-gravity circuit and the transformation of GRG into non-GRG, as mainly explained by gold particle reshaping, will be discussed. The knowledge gained from the shape analysis will be used to develop shape distributions and partition curves for the classification of shapes.INTRODUCTIONGravity concentration using centrifugal concentrators has gained increasing popularity since the invention of the enhanced gravity concentrators in the nineteen eighties. Among these, the semicontinuous centrifugal gravity concentrators are most commonly used for recovering gold and platinum group minerals (PGM) from grinding circuit streams. The benefits of gold gravity recovery are now well understood and the acceptance by the mining industry is overwhelming. The occurrence of reasonable amounts of gravity recoverable gold (GRG) in an ore prompts gold mills to install gravity circuits. Thus, the increased use of gravity concentration has necessitated a better understanding of the behavior of gold in grinding circuits and of the factors affecting the performance of the gravity concentrator (Laplante et al., 1995). Due to its high density (19.3 g/cm3 when pure) and malleability properties, gold tends to accumulate in circulating streams making it attractive for gravity recovery. The gravity recovery units are typically installed on a bleed stream of the cyclone underflow, mill discharge or cyclone feed."

Jan 1, 2011

By R. Dell Davidson

This report contains the results of the work performed by Dayton T. Brown. Inc., Testing Laboratories, Bohemia, New York, under the Department of Interior, Bureau of Mines, Contract J0166089 entitled "Performance Testing of Air-Line Linking Components." The objectives of the program consisted of the following: 1. To conduct engineering tests that will provide data to recommend the performance criteria for air hose and piping connections. 2. To determine the requirements for restraining devices which are used to comply with MESA Health and Safety Standards 55, 56, 57,13-21.

Jan 1, 1978