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By John Jonkman

Many companies in the mining and minerals processing industry are finding themselves in the transition stage from the Industrial Age to the Information Age and are trying to become prepared for the Knowledge Age. To remain competitive in the decades ahead, they are faced with integrating the enterprise through the use of computers and networks. This paper discusses some common human and organizational barriers to enter- prise integration. It proposes how to develop the organizational and human' networks to match the capabilities of the technical networks which are being' implemented. Ten practical considerations are then presented for consideration in the executive suite in addressing the human side of implementing the computer integrated enterprise.

Jan 1, 1989

By R. L. Wiegel

A well-defined geometric model for a mineral system and its liberation by size reduction is used to show the relationship between true volumetric particle composition and the composition estimates obtained by the measurement of linear intercepts or areas of simulated polished sections of particles. Based on this information, a transformation is developed between the areal measurements and the volumetric composition for this idealized mineral system. Key words: Gaudin random liberation model, Mineral liberation, Particle composition measurement

Jan 1, 2010

In this study, a 3D model of the shovel motion based multi-body system dynamics in the Automatic Dynamic Analysis of Mechanical Systems (ADAMS) environment was developed. The kinematics model of the shovel was modeled as a multi-body system, which comprises the lower, upper, and the attachment mechanisms. The Euler-Lagrangian equations were employed as the computational framework to describe the dynamic behavior of the model. A virtual prototype of the shovel was built in the ADAMS software environment. This environment allows the visualization of a 3D motion of the general mechanical system and the prediction of interference of the moving components of the shovel. The numerical analysis and animation of digging, swinging and dumping motions for the shovel were performed. The superimposed display of the deployment for the shovel in three phases allows a detailed examination of the dynamic interference among assembly components. This research provides a solid foundation for further shovel dynamics performance studies. Keywords: Shovel, Spatial Kinematics, Virtual Prototype, Visualization

Jan 1, 2009

By Scott W. Harrison, Richard E. Aaseng

In 1993 Ispat Inland Mining Company began mining its Laurentian ore reserve, which has six distinct ore types that are extremely variable. Initially batch processing was necessary to optimize mining equipment utilization. The variability as found in the ground was compensated for in plant operation, which proved ineffective. When the last of the six ore types was introduced in 1997, production, quality, and cost were seriously impacted. In-pit blending was the solution developed by the process management team to provide the plant feed required to economically process all six ore types in the Laurentian reserve.

Jan 1, 2000

By Joan Carles Casado Ortega, Mitchell Gerdtau, Sandeep Pyakurel, Eric Crocker, Frank Perrone

The Parallel Thimble Shoal Tunnel (PTST) project is a part of the Chesapeake Bay Bridge- Tunnel (CBBT) complex. The project involves the construction of a two-lane bored tunnel under the Thimble Shoal Channel between Portal Island #1 (the southernmost island) and Portal Island #2. The new PTST will be the rst transportation tunnel constructed in the Mid-Atlantic region by a tunnel boring machine (TBM). This paper describes the design and construction of the tunnel approach structure in an open marine environment with the strategies employed to overcome the various construction challenges. The project is unique since the entire tunnel approach structure is built on a very limited area within an open marine environment without any reclamation of the existing island.

Jun 23, 2024

By John Brett

BHP Australia Coal Pty. Ltd. (BHPAC) manages and, through its parent company BHP, partly owns seven large opencut mines in the Bowen Basin of Central Queensland, Australia. In terms of developments in surface mining in Australia, the operations of BHPAC are as representative as any. The seven mines managed by BHPAC produce a combined total of about 40 Mt/a (44 million stpy) of mostly high quality coking coal. They also produce small but increasing amounts of thermal and PCI coal. Virtually all of the coal produced is sold on the export market. In 1993, Australia exported 133 Mt (146 million st) of coal. Salable production was 172 Mt (189 million st) in New South Wales and Queensland and 180 Mt (198 million st) nationwide. Mining systems Surface coal mines in Queensland can be typified as large, long-strike-length, shallow-dipping and sometimes multi-seam dragline operations. There are exceptions. Blair Athol, for instance, works a 30- to 40-m (100- to 130-ft) seam beneath shallow cover but is still a dragline operation. Moura is truly multi-seam and steeper dipping but also is still a dragline operation. Mines in the Ipswich area are small shovel-truck operations.

Jan 1, 1995

By Wayne W. Murdy

Since 1993, Newmont Mining has been growing through the development 'q of three major foreign mining operations with a fourth under construction. The first project, Yanacocha in Peru, began operating in October 1993. This occurred at a time when political and business risk in that country was considered high. In 1995, Newmont began operating the Muruntau joint venture in Uzbekistan. It is the first mining project of its kind in the Confederation of Independent States (CIS). In early 1996, Newmont started operating the Minahasa Mine in Indonesia. In early 1997, Newmont began construction of a $1.9-billion project in Indonesia. The company is also completing a feasibility study with its partner for the development of a gold operation in Mexico. All of these projects have been considered "risky" by most standards. Newmont has been successful in all of them through risk mitigation programs. These programs include using strong and successful in-country partners, concentrating on developing a strong national workforce with minimal expatriate employees, using World Bank, European Bank for Reconstruction and Development (EBRD) and International Finance Corp. (IFC) financing and building and maintaining strong ties with host governments.

Jan 1, 1997

By W. J. Douglas

Before discussing minicomputer software for the mineral industry, it is helpful to explain some of the computer program terminology. Most of the terms are the same as those applied to large computers. A computer system consists of a machine (hardware) with electronic and mechanical components and instructions (software) that define its operational logic and sequence. This logic is described by sets of commands grouped into programs. Each program has specific objectives related to the computer's operation and to production information from computer data that are input and processed. Software, therefore, is a general term applied to any type of computer program. Instructions to the computer are communicated through languages that convert logical and arithmetic statements into machine operations. The languages may consist of statements resembling mathematical or logical phrases understandable by humans, or they may be coded statements with no apparent resemblance to spoken language but readily understandable by the computer. Computers also translate higher level languages such as FORTRAN or COBOL into machine languages using other programs called Compilers. Programs written in these higher level languages are generally called source code. However, programs written in computer assembly language may also be called source code. The compiled version of the program after it has been translated by the compiler software is called object code. Programs used to "instruct computers how to be computers" are generally called systems software. They relate more to computer operation than to producing externally usable results. Programs producing information for many users-engineers, accountants, managers-are termed applications software. For the most part, applications software is the principal concern of the mineral industry. Programs are developed to fit user requirements as interpreted by programmers. Programs vary in quality, precision, efficiency, accuracy, and complexity, depending on programmer skills and abilities and programming decisions forcing design tradeoffs. A well written program should have speed, efficient use of available hardware resources, accuracy, and an inherently logical structure that aids documentation and subsequent modifications. Programs developed to fit specific requirements are termed customized software. A program organized and prepared for general commercial use is called a package, or a software package, and includes documentation for program use. A form of customized software that takes an existing program or package as its starting point and modifies it is called a customized package. A minicomputer program can be stored on computer cards, standard magnetic tape, magnetic cassette tape, floppy disk, or hard disk. The software purchaser or lessee may select one or more of these media when specifying a program in a software contract. Supporting documentation may include a listing of the program instructions linkages, hardware and storage resource requiremnents, flow charts, and programmer and user manuals. The purchaser must carefully make and clearly understand specifications for media and format of program delivery. This assures that delivered software is compatible with the intended hardware. Mineral Industry Attitudes Toward Computer Software The mining industry has traditionally been conservative concerning computer applications. Furthermore, large computer costs have made these systems accessible only to large companies, for the most part. But in the past few years, mining software systems developed at schools such as Pennsylvania State University and Virginia Polytechnic Institute have gained wider acceptance in the mineral industry. More mining engineers now have academic training in computer application, and computer use is now more acceptable to the mining industry. Mining managers in decisionmaking positions are faced with a new generation of computer technology resulting from the rapid evolution of minicomputers. Not too long ago, manufacturers such as Digital Equipment Corp., Data General, and Hewlett-Packard were considered newcomers. They are now established companies. In addition, Apple, Radio Shack, Commodore, and others have emerged in the growing microcomputer industry. So the mine manager or mining executive now has more options. Mining Software is Limited Along with the rapid evolution in hardware development, much general purpose software is now being developed for minicomputers. The 1981 Apple Software Directory can be obtained for about $14; Radio Shack published the Application Software Source Book in three volumes for $1.95 each. Brochures describing software can be obtained for other minicomputer manufacturers by contacting local sales representatives. Hewlett-Packard software can be obtained and exchanged through HP user's groups. Manufacturers' programming staffs are generally concerned with developing applications software. In some instances, manufacturers will recommend software developed by their hardware users. Until now, however, software development for mining applications has been minimal. This should not be surprising, since software development traditionally lags hardware development by several years. A review of A Directory of Computer Software Applications/Mini-Computers and Micro-Computers, August 1977-1980, published by the US Department of Congress, National Technical Information Service, contains many entries and subject areas. General applications include some references to tunneling machines, but there are virtually no entries specifically relating to

Jan 11, 1981

By R. W. Smith, K. A. Altman

The use of activated alumina for the removal of selenium from heap leach detoxification solutions was studied at a laboratory scale. Three different aluminas were studied, one unmodified and two chemically modified to function better in a basic pH range. The best performer, Discovery Chemicals DD-6, readily accumulated selenium oxyanions. Furthermore, it could be stripped of selenium and several metals by a mild caustic solution (pH 11.5 – 12.0) and regenerated for further use. Tests using - 600 µm, + 300 µm (28 x 48 mesh) material indicated that 96 % could be removed from solution and using – 1.18mm, + 600 µm (14 x 28 mesh) material 91 % could be removed. However, soluble silica can accumulate on the activated alumina and subsequently interfere with its regeneration and should be removed from the detox solution prior to use of the adsorbent.

Jan 1, 2003

By W. R. Hail

A proactive design and construct approach was used to remediate the Warm Springs Ponds Complex near Anaconda, Montana under "Superfund". The pond complex is used for treatment/settlement of heavy metals and is a repository for 19,000,000 cubic yards of tailings, precipitates and associated sediments. Remediation has resulted in treatment/settling capacity for flows up to the 100-year flood (3,300 cfs); expansion from 5 to 11 ponds in series requiring 12.5 miles of new or improved embankments with associated hydraulic structures; flood protection for the 0.5 Probable Maximum -Flood (PMF) (70,000 cfs); and closure of exposed tailings along with aquatic and terrestrial habitat enhancement.

Jan 1, 1995

By J. J. Peshel

As per the current conceptual design presented by the Department of Energy, the exploratory shaft facility (ESF) becomes a part of the repository if the Yucca Mountain site is found suitable for repository development. Therefore, the design of the ESF should be compatible with the performance requirements for the repository. The construction methods selected should limit to the extent practical, the degree and the extent of damage to the surrounding rock mass. The ESF construction and operation should be compatible with the site data gathering activities, such as geological, thermomechanical, hydrological and geochemical testing.

Jan 1, 1991

By T. Dombrowski

Acid-activated montmorillonite is used worldwide as a catalyst and as a sorbent for the enhancement and purification of petroleum products as well as vegetable and animal-based fats. The solid-acid character of the activated montmorillonite is imparted by the manufacturing process, giving it unique properties that are exploited in these industries. Several international companies and a multitude of local clay producers are focusing on improving the efficiency of their standard and specialized products. This paper will describe the use of acid-activated montmorillonite in traditional sorbent applications, as a solid acid catalyst, and other new uses.

Jan 1, 1997

By D. Hodouin

Abstract. Dynamic experiments were performed in a continuous open-circuit 40x40 cm ball mill using a pseudo-random binary sequence of the feed rate and measuring the variations of the discharge particle-size distribution. The impulse response is calculated by a cross-correlation technique. Then a model involving a discrete transfer function and a time-series stochastic equation is calibrated using maximum likelihood methods. Based on this empirical model. a minimum variance controller with constrained input is designed and its performances are compared. by simulation, to the performances of a conventional PID regulator.

Jan 1, 1987

By Stephen W. Denton

Planning a mining operation in Alaska will involve the investigation of many parameters common to mine planning anywhere. However, there are some unique circumstances that must be recognized when one considers development of mining operations in Alaska. This paper will not attempt to provide a blueprint for mine planning in Alaska, but hopefully will provide a better understanding of the truly unique nature of the northern latitudes. Given this understanding, the mine planner can better assess the potential hurdles along the road to a successful mining operation. The regulatory trend towards uniform standards for mining throughout the United States exemplifies the necessity for Alaska to prove its unique position in the natural resources picture. The factors which make Alaska truly different from the "Lower 48" can be summarized by four points 1) Remoteness and Size 2) Seasonable Extremes 3) Geologic Immaturity 4) Vegetation and Wildlife

Jan 1, 1984

By D. C. White

The Vulture Mine near Wickenburg, Arizona was a major gold producer from 1863 to 1942, having yielded about 11,000 kg Au and 8,000 kg Ag. Gold occurs as coarse native metal and electrum in quartz veins and also finely disseminated within a quartz monzonite sill and its silicified wall rock. The sill is semi-conformable within a Proterozoic volcaniclastic-dominated sequence all dipping north about 35°. Early mining focused on the vein-hosted gold particularly in the immediate hanging wall and footwall of the sill. Later efforts included some open-pitting of the outcropping sill and adjacent altered and mineralized rock. Two sets of post-mineral faults have complicated the orebody geometry.

Jan 1, 1988

By W. J. Atkinson

Since the inception of the Ashton (formerly Kalumburu) Joint Venture in 1972 the parties have expended 524 million in exploration for diamonds in the Kimberley region. This has resulted in the discovery of the currently subeconomic Ellendale deposits in 1976/77 and the economic Argyle - Smoke Creek Deposits in 1979/80. In addition to Argyle and Ellendale some 90 kimberlitic and lamproitic bodies have been discovered grouped broadly into three provinces, on the west, east and north margins of the Kimberley block. These bodies range in size from dyke-like features less than one metre in width to pipes with a surface area of 128ha. The bodies with larger surface area are volcanic crater deposits, infilled with air-fall and water deposited tuffs and epiclastic sediments.

Jan 1, 1984

By Jr. Pitts

Elevation of surface charge density on colloidal particles in the presence of a high potential electrostatic field is demonstrated as a viable technique for preventing the accumulation of solids in solvent extraction circuits. The effect of the technique is manifest by relative turbidity measurements between pregnant leach solution and raffinate, by changes in the character of the sludge accumulations, by alteration of the zeta potential of particulates, and by a general reduction in the mass of solids.

Jan 1, 1992

By Steve Kral

When the price of gold cracked the US$9.60/g(US$300/oz) mark last year, the gold-mining industry began to crank up again. This followed several years of gold prices that had languished in the mid-200s. Existing mines increased production and mines that had lain dormant for many years were getting second looks. The United States still produces a large amount of gold. But not much of the new production is coming from that country. Instead, strict environmental regulations still have companies wary of trying to invest the millions needed to start a new mine or expand existing ones. And after years of studies and negotiations between legislators, environmental interests and the mining industry, the United States still has not crafted a new mining law.

Jan 1, 2003

By Fulvio V. Fonseca

The Trombetas bauxite deposits were discovered by ALLAN, as from the original work of the geologists Drs. E. E. GREIG and 3.A. STAARGAARD on the axis of the Amazon river, between Manaus and Santarem - (see fig. 1). With research licences obtained in 1965 by the SANTA RITA BAUXITA - a subsidiary of ALAN a group of Brazilian geologists, under the supervision of IGOR MOUSASTICOUSHVILLY, begins researches on the areas of Parintins, Juruti and Mathias with unsatisfactory results. In 1966, photographs obtained from the US Air Force and the Brazilian Oil Company PETROBRAS -, covering an Amazon region between Parintins, Santarem and north of Trombetas river, permitted the identification of a great number of plateaux between the Nhamunda and the Trombetas rivers. Based on this information, a research group has worked intensively from 1966 to 1967 allowing the discovery of the trihydrated bauxite in a quite large area. After five years of intense work and analysis of approximately 56.000 samples, near 500 million of tonnes of bauxite are evaluated on the several plateaux of the, area, thus insuring the commercial exploration of these deposits. Such discovery places Brazil among the detainers of the main bauxite stocks of the world and as a potential exporter.

Jan 1, 1980

By Gregg J. Hodges

The Stillwater Mining Company, a partnership of The Pittsburg & Midway Coal Mining Co. and Manville Corporation, began commercial production of flotation concentrates from the western hemispheres' only primary platinum palladium deposit at Nye, Montana in March 1937. In the fall of 1987 an integrated pilot plant testing campaign of electric furnace smelling and oxygen? blown converting confirmed the feasibility of further upgrading to semi? refined matte or 'white metal". In the summer of 1990 the production smelter was brought on-line at Columbus, Montana. This paper describes the technology transfer from the pilot to the production smelter. Emphasis is placed on flowsheet development and the scale factors between the test and production furnaces and gas cleaning plants. The metallurgical results of the pilot plant and of the early months of production of the commercial works are also compared.

Jan 1, 1991