Search Documents

By A. Yazadni-Chamzini

Considering the nature of open pit mines, harvest volume, it usually is required to remove a lot of waste to access to mineral planned grade. So, one of the most important part of open pit mines design, is waste dump site selection. Many factors are effective in waste dump site selection. These factors are sometimes in conflict with each other. So selecting the desired location for waste dump is a process complex and multi-criteria decision making. There are a variety of methods for decision making under complicated condition, such as fuzzy, Delphi, multi-criteria decision making and Expert system methods can be hinted. VIKOR method, which is one of the decision making multi criteria methods, is useful tool for decision-making. On the other hand with regard to uncertainty in decision-making, fuzzy approach is a useful tool for this purpose. This article has tried to select the best waste dump site in Sari Gunay Gold Mine by Fuzzy VIKOR. The results show that C position has a higher priority than other positions.

Jan 1, 2012

By George S. Rice, F. B. LANEY, A. J. Lanza, Edwin Higgins

Under its organic act the Federal Bureau of Mines is directed to conduct investigations relating to the improvement of health conditions in the mineral industries. This report describes the lead and zino deposits and the mining methods employed in the sheet-ground area of the Joplin district, Missouri, and discusses the causes and the methods of abating rock dust in the mines, the chemical and physical characteristics of the dust, and the quantities present in mine air. Although the preliminary investigation included a number of the "soft-ground" mines, the writer spent the larger part of his time in the sheet-ground mines, for in them alone was siliceous dust found in appreciable quantities. Some results of the preliminary investigation have been published by the Bureau of Mines in Technical Paper 105.a The territory covered in t~lCpreliminary investigation, during the period between November 7 and December 6, 1914, embraced parts of Jasper, Lawrence, Newton, and Greene Counties, Mo., and outlying districts in Kansas and Oklahoma. The remainder of the field work, to which 84 days during the period from February 9 to July 19, 1915, were devoted, was confined to the sheet-ground mines, the most important of which are situated in the vicinity of Joplin, Webb City, Carterville, and other smaller near-by towns in Jasper County, Mo.

Jan 1, 1917

By Wilson Bardales

El presente trabajo describe la experiencia de la Gestión de la Calidad en la Cía. Minera Poderosa S.A., específicamente en el rol que desempeñan los Círculos de Mejoramiento Continuo (CMC´s) como un vehículo efectivo para alcanzar los objetivos de la empresa. Los CMC´s están integrados por trabajadores de un mismo proceso, a quienes se capacita en el manejo de herramientas, técnicas y metodologías de la calidad, con la finalidad de realizar mejoras en los procesos. En ese sentido, en la compañía minera La Poderosa, la administración es participativa y el directorio difunde las políticas, para lograr la rentabilidad de la empresa. Así también, los mandos medios definen los objetivos y estrategias, desplegándola en cascada a la supervisión y estos a su vez, al personal de línea. Este concatenamiento de responsabilidades y la participación de los CMC´s aseguran el alineamiento y control de la gestión.

Sep 12, 2005

Jan 1, 1990

By Joshua Hoffman, Braden Lusk, David McLane, John Rathbun

The dynamics of explosive detonations are understood; however recreating a real-world, to-scale scenario is costly. The use of a shock-tunnel allows testing to be done on a smaller scale, with the simulated effect of a large explosion. Analyzing explosive waveforms using this method can greatly reduce cost in testing blast-resistant products, such as anti-terrorism devices, mine safety products, and military equipment. The purpose of this project is to better the understanding of how the waveform dynamics of an explosive detonated within a shock-tunnel differ from those in an open-air arena test.

Jan 1, 2011

By John Reilly

Traditional methods of project procurement of have remained virtually unchanged in the U.S. infrastructure construction industry for more than 50 years. The traditional method, Design-Bid-Build (DBB), uses a two-step process that separates planning and design from construction. Design is generally done by the public agency and their consultants and the subsequent construction contract is procured from the private sector, almost always by a “low-bid” approach. This method has worked well for many projects, delivering quality work for the lowest bid price. This is particularly true for those projects where the work, and the public agency’s management procedures, are well understood by the contracting community and there is relatively low uncertainty in the work or conditions, particularly geotechnical conditions for underground construction. However, concerns exist with the DBB process. It is time consuming because all planning and design work must be completed prior to beginning any construction work and it is of concern for complex or large projects, plus those with significant risk, where the separation of design and construction, in conjunction with pressures resulting from the low-bid environment, often result in substantial cost and schedule increases. Frequently, these increases occur in a non-productive, inefficient, adversarial work environment leading to claims, disputes and costly litigation (Quick 2002).

Jan 1, 2007

By Francis C. Lincoln

"INTRODUCTION As part of a general investigation of the zinc-producing area of southwestern Wisconsin, the Bureau of Mines undertook a limited amount of exploratory drilling in the immediate vicinity of the New Dale Rundell mine, in the Mifflin District of Iowa County, Wisc.The work was carried out during the early part of 1945, at a time when all effort was being directed toward increasing production of metals important to the Nation's war program. Bureau of Mines engineers decided to conduct exploration at the New Dale Rundell mine after a preliminary study of available data showed a reasonable possibility of indicating an important deposit. Before the Bureau of Mines investigation, 50 holes had been drilled in the vicinity. Of this number, 18 encountered ore of minable grade. Subsequently the mine was developed and operated for a brief period; however, work was stopped before all of the ore disclosed by drilling had been mined. There appeared to be a correlation between the ore shown by the drilling in the New Dale Rundell mine and another disclosure some 1,500 feet to the northwest. The Bureau of Mines exploration was pinned to explore this possible correlation. Of the 7 holes drilled by the Bureau of Mines, 3 disclosed minable ore beyond the limits of previous drilling."

Aug 1, 1946

By C. C. Clark, P. W. Patton, B. M. Stewart

Handling materials in underground mines continues to be a major safety problem. To help reduce materials-handling injuries, researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health are investigating those materials-handling tasks in underground mines that appear to generate a high number of injuries. Data from the Mine Safety and Health Administration for the years 1989-1999 were studied to find out if there were any trends in materials-handling accidents and if so, to determine what tasks were involved and the sources of injuries. Several underground coal and metal mines were visited to document innovative materials-handling technologies. Considerations for safety training and mechanization needs for continued reduction in materials-handling injuries are described.

Jan 1, 2002

By L. K. Eigenbrod

Throughout the mining industry, pneumoconiosis is one of the most severe occupational health problems being faced. The goal of completely eliminating pneumoconiosis as an occupational health hazard was underscored by the Federal Government with its enactment of Public Law 91-173 (Federal Coal Mine Health and Safety Act of 1969). Under this law, permissible dust level standards will be placed at 2 mg/m3 in mine atmospheres by December 30, 1972. The mining industry is thus faced with the tremendous technical challenge of achieving this level. Two basic questions can be raised with regard to this legislation. First, does a maximum dust concentration of 2 mg/m3 prevent the occurrence of pneumoconiosis? Secondly, can this dust standard be achieved using presently available methods and equipment? A precise answer to the first question has not yet been developed by the medical profession. Studies are continuing on the origin, prevention, and therapy of pneumoconiosis, and permissible dust levels could become even lower as medical evidence accumulates. The mining industry has addressed itself to the problems of dust con-tro1 for many years as related to personnel health, explosive mixtures, visibility, and machinery damage. Dust control methods being employed involve

Jan 1, 1971

By A. E. Ketler

Conventional Atmospheric Monitoring System (AMS) installations for monitoring CO, CH4, O2 and air-velocity throughout underground mines are usually relegated to a modest 3-5 mile extent and with data communication speeds confined to a ponderous 1-5K baud range. New US-MSHA and state regulations require fast reporting of unsafe conditions, and the old 20-30 minute updates are no longer acceptable. To communicate farther and faster has always been a problem, because data reliability degenerates with excessive distances and high speeds. Because of this, very large mines often resort to costly optical-fiber media, using expensive OF cables and repeaters to obtain the necessary coverage. This entails high initial cost, as well as high maintenance and downtime costs to repair or replace broken optical fibers. Rel-Tek has pioneered with its DX-Bus communication data highway, which uses inexpensive twisted-pair telemetry cables, which can now communicate well into the 20-mile extent of the largest mines -- normally a brick wall for low-tech AMS systems. This extended range, enables the use of twisted-pair cables and provides a low cost alternative to OF systems. This paper discusses the DX-Bus, and its latest accomplishment, the ?B-LINK,? a unique high-speed communication repeater that maintains the 19.2K-Baud data rate. On-going innovations to our workhorse Millennia-DX computer software have kept pace with this extra speed/distance phenomenon, resulting in a dually-optimized AMS package: both hardware and software. Cost savings are substantial, and at no sacrifice of reliability ? nearly always at 100%. Sensor updates are measured in seconds, not minutes and hours. Twisted pair copper cable is cheap to purchase and install and a breeze to maintain. Rel-Tek uses the B-LINK's wide branching capabilities to enable the AMS to extend 20-miles both far and wide. Actual experience in large US coal mines -- both longwall and continuous mining operations -- confirms the large mine performance. The ventilation and safety benefits to the mining industry are immeasurable.

Jan 1, 2009

One of the biggest challenges for the mining industry is, quite literally, how to the keep the equipment rolling. There is a limited amount of companies that manufacture the 4.2-m- (14-ft-) tall, 5,670-kg (12,500-lb-) tires needed for the haul trucks that are approaching the 362 t (400 st) pay-load class, such as Terex?s MT6300-AC and Caterpillar?s 797F. And, while these might be the most impressive tires, they are not the only ones that are in short supply. The shortage of tires has affected just about every kind of machine, and the demand for those tires has been extremely high for more than five years with no end to the shortage in site. American Tire Corp. (www.americantire.us) is one of the companies working to supply tires to the mining industry. It announced that the demand for its 1.6-m (63-in.) tires that have a zero failure history globally is great and that the company signed contracts worth more than $500 million at MinExpo. A relatively new player in the field of large tires for mining equipment is Titan Tire Corp., (www.titan-intl.com), a subsidiary of Titan International Inc. It shipped its first 1.6 m (63 in.) off-the-

Jan 1, 2008

Considerable improvements in diamond drilling equipment have been made since the early 1950s. A recent drilling programme, however, at Williamtown, near Newcastle, carried out by the Joint Coal Board on behalf of the Electricity Commission of New South Wales, emphasized deficiencies in existing equipment when particularly diflkult coring conditions were encountered.Spurred by unacceptably low recoveries in coal seams in this area, the Joint Coal Board devised and developed, with the assistance of the Electricitv Commission, a new typc core lifter and a special 26 ft triple tube core barrel, designed to operate in conjunction with it in bad coring conditions.The core lifter, whieh is propped open clear of incoming core during drilling, is activated by fluid impulses generated inside the core barrel. It can be used with double tube barrels when drilling firm rocks whichdo not change diameter by compaction inside the barrel.Softer rocks. such as clayey types, require the use of a rriple tube barrel.Results from testing carried out to date in difficult areas in New South Wales coalfields have shown that greatly improved results can be obtained with the new equipment. Although developed essentially for coaldrilling, the new core lifter and barrel could be adapted to other fields of diamond drilling. Even in areas where no great coring difficulty is encountered the cost advantage deriving from the greatly inereased life of the core lifter and the adaptor in which it is housed could justify its use.

Jan 1, 1967

By R. B. Crookston

Oil shales differ from coals in that they contain less carbonaceous material, convertible to volatile hydrocarbons, and more inorganic rock. In all pre-commercial oil shale development, involving extensive full scale mining operations, there have been no explosions. However, large scale mine tests with oil shale dusts by the Bureau of fines showed that propagating explosions could be induced under certain circumstances. Laboratory tests were conducted on a broad spectrum of oil shale dusts to define chemical properties and to seek correlations with subsequently determined fire and explosivity properties. These latter properties, indicative of safety hazards, increased as the Fischer assay oil yield of the dusts increased and as particle size decreased. Laboratory data were used to relate fire and explosivity properties of oil shales to those of coals and other carbonaceous materials and to assist in the identification and evaluation of potential hazardous situations which may be encountered in oil shale mining and processing.

Jan 1, 1978

By R. J. O'Dea

"The United States hat large reserves of titaniferous iron ores that are a potential future source of both iron and titanium. Although it is not now economically feasible to recover iron and titanium metals from these ores, they may become important in times of stress and, in some instances, already have served as a source of pigment-quality titania.The iron- and titanium-bearing constituents of the ores considered in this report are not completely separable from each other by ore-dressing methods, and chemical (or smelting) procedures must be employed. It is im¬portant, therefore, that information be available concerting their reactivities. The most important titanium-bearing constituent is ilmenite (FeTiO3), the thermodynamic properties of which were discussed in a previous publication.3/ The results of thermodynamic studies showed that both hydrogen and carbon monoxide are relatively ineffective reducing agents for the iron in limonite. On the other hand, carbon theoretically is effective at tempera¬tures above 8510C., at which. point the combined equilibrium pressures of CO and CO2 from the reactionsFeTiO3 + C = Fe+ TiO + COand200 = C+ CO2reach 1 atmosphere.This report gives results of small-scale tests of selective reduction by carbon of the iron in titaniferous iron ores, both with and without addition of sodium carbonate. It is shown that the bulk of the iron may be reduced and separated without serious reduction or loss of titanium. Three Wyoming ores, Iron Mountain, Shanton, and Taylor, wore studied. The principal factors investigated were temperature, time, carbon:ore ratio, particle size, and sodium carbon ore ratio.Two methods of investigation were employed. In the first, intimate mixtures of ore and carbon were roasted and the reduced iron and titanium evaluated by leaching with dilute sulfuric acid and analyzing the leach solution (and, in some instances, the dried residues).Twenty grams of ore were mixed thoroughly with carbon and tamped into an alundum thimble having a loosely fitting cover. The thimble and contents were placed in a test-tube end porcelain tube and heated to the desired temperature in a Globar tube furnace. The open end of the porcelain tube was connected to a bubbler containing sulfuric acid, in a manner that permitted complete shut-off of the tube when desired. This allowed removal of the tube from the furnace at the end of the roast period without exposure of the contents to the atmosphere."

Jun 1, 1946

By J. R. Thoenen

Occurrences of titanium, zircon, and other heavy minerals are widespread in Florida. Deposits concentrated as "heavy sands" by wave and wind action have been mined an or near Atlantic coastal beaches since 1916. An important inland concentration at Trail Ridge; .believed, to have formed along an ancient share line, was disclosed by preliminary investigations (1947) by the Bureau of Mines. This report describes investigations to determine the extent and grade of "heavy-sand" concentrations in other inland stabilized dune areas in the central and northeastern parts of the peninsular region of the State (fig. 1). Portions of the central highlands south of Trail Ridge and terraces and dunes in the coastal lowlands region, east and northeast of the ridge were investigated. Holes were drilled in 10 areas (see table 1 and fig. 2) along State and County roads and on private property. They were spaced 250 to 2,000 feet. apart to obtain a cross-sectional picture of "heavy-sand" content in the dune areas. These sections were generally placed in east-west directions normal to the general trend Of the peninsula to intercept one or more of the ancient shore lines in the various areas (figs. 3 to 13, incl.). A total of 433 drive piped and 333 jet holes were drilled, and 7,293 bulk and core samples were taken. Intermediate holes were placed at closer intervals when field analysis indicated 1 percent or more of heavy minerals present. All of the holes drilled and the analysis of samples that contain 1 percent or more of heavy minerals are listed in table 2. Profiles (figs. 14 to 20, inclusive) show the more favorable concentrations, which are irregular in outline and erratic in mineral content. The highest concentrations averaged 1.0 to more than 2.0 percent heavy-mineral content, but a few individual hole samples exceeded 3.0 percent in grade.

Jan 1, 1949

By L. S. Rivett, U. M. Oko

The Strathcona mine, with a large new underground operation and concentrator, was recently brought into\ production by Falconbridge Nickel Mines Ltd. The tailings disposal and water utilization problems at Strathcona are described in this paper, with sections devoted to the Moose Lake watershed system, tailing impounds, the construction of dams and the operation of the Moose Lake neutralization plant for the elimination of acidity, including the equipment used.

Jan 1, 1971

By S. J. Boone, A. Poschmann, C. Pound, A. Pace

San Diego’s Stadium Conglomerate consists of poorly cemented cobbles, gravel, sand, silt and clay. Conventional laboratory and in-situ testing is not suitable for characterizing its engineering properties. Although the formation is often considered a “rock” its behavior is more readily modeled using soil mechanics. Static and seismic design of a tunnel for the Mission Valley East light rail extension required that the stress-strain characteristics of the ground be identified over a broad strain range. Geophysical methods and field plate load testing were used to develop a full non-linear stress-strain model of the expected ground behavior. Quantification of the coarse material distribution was also required for selection of tunneling methods and construction considerations.

Jan 1, 2001

By Tom Dettweiler, Robina Sharpe, Wright. Michael

The International Seabed Authority and a number of countries have or are in the process of developing environmental impact assessment guidelines and legislation for seafloor mineral development. The formal decision to grant a project an environmental permit is based on an environmental and social impact assessment (ESIA), culminating in an environmental impact statement (EIS). The EIS needs to be supported by sufficient data upon which an assessment of impacts can be made and mitigation measures developed. Given the remote locations of many seafloor prospects, collection of sufficient environmental data to inform an EIS is often a difficult, expensive and lengthy process.

Sep 1, 2014

By Richard E. Ray

Conventional concrete block plastered with a cemantitious coating is the most common material used in the construction of perma¬nent stoppings to direct airflow in underground mines in the U.S.A. All mines experience various degrees of strata convergence depending upon depth of overburden, geological conditions, and type of roof support employed. Strata convergence will cause cracks and joint openings in masonry stoppings, resulting in significant air leakage losses. Where strata convergence is severe, complete structural failure of the stopping can ultimately occur. Reconstruction of damaged or destroyed stoppings adds expensive overhead to mining operations, and even greater expenses are incurred from the additional fan horsepower required to overcome leakage losses. Ideally, a stopping should maintain high resistance to airflow while yielding to strata convergence. By properly incorporating "Max-Seal" polyisocyanurate rigid foam material within the masonry block structure, stopping service life can be increased several-fold in mines experiencing strata convergence problems such as floor heave, roof loading, and lateral rib movement.

Jan 1, 1984

By A. R. MacLean

This mine is situated at Point Aconi, Cape Breton , Nova Scotia, and is a replacement for the 100-year-old Princess Collie ry. It is a slope mine which is the continuation of a s trip mine operation. There are fives lopes from the surface driven with Dosco Dintheaders - this marks the first time these machines were used in North America. There are four room -and-pillar sections, each equipped with a Lee Norse HH106 continuous miner, a "Top Dog" roof bolter and two Wagner diesel Teletrams. There are also two Eimco 913 diesel LHD's , which are used for clean-up in the mines. This paper describes the mining operations of this 800,000-tpy mine which, in less than a year and a half , has been developed to the stage where four sections are producing coal at the desired rate.

Jan 1, 1978