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By Ronald Branstetter

Gaseous and particulate exhaust emissions from 20 diesel engines in service at five underground mines were measured with high accuracy instrumentation. The engines that were tested were checked for faults or maladjustments. The vehicle and engine maintenance organization was studied at each mine and an idealized maintenance program was devised. Faults were induced in a new diesel engine to determine their effect on the characteristics of the exhaust emissions. The results, conclusions and recommendations from this investigation are presented in this final report.

Jan 1, 1983

By Mark I. Copeland

This study was conducted by the Bureau of Mines to determine the effect of steel reheating practices in burning natural gas on the amount of silicon required to prevent the formation of copper on steels containing up to 1 wt-pct Cu. Formation of copper, which causes surface hot shortness, was readily prevented by as little as 0.3 wt-pct Si and by 2 vol-pct excess oxygen in the furnace atmosphere when reheating steels containing up to 0.8 wt-pct Cu. Up to 0.8 wt-pct Si content and careful control of reheating conditions were necessary for steels containing 1 wt-pct Cu. Best conditions for these steels were reheating to 2,200° F (1,205° C) in burning gases containing 2 vol-pct excess oxygen, and then to higher temperatures in gases of 6 vol-pct excess oxygen. Slag and mold wash were not detrimental on steels reheated for 8 hr by a soaking-pit-type furnace schedule, but they were problematical on steels heated for 2 hr by a pusher-type furnace schedule. The effect of silicon contents on scaling rates also was determined.

Jan 1, 1974

By A. Noble

The design of separation circuits can be a complex, labor-intensive and costly process. While the engineer?s experience along with extensive data sets and simulation are crucial tools for determining the final solution, a more fundamental approach is suitable to compare preliminary options and reduce the number of potential alternatives. In light of this need, the authors have developed the Circuit Analysis Reduction Tool (CART?). This software package relies on the fundamental principles of linear circuit analysis; however, the solution methodology has been streamlined to automatically incorporate stream splitting and unique separation performance for each unit. The resulting tool allows preliminary analysis of circuit designs without the need of detailed feed characterization. In addition to the basic analytical approach, this paper supports the veracity of the methodology with several simulated examples for various separation models.

Feb 27, 2013

By M. Beus, S. Inverson, B. Stewart

Abstract Recent ore pass failures have underlined the need for improved designs, standards, structural mon¬itoring methods and better hang-up prevention and removal tech¬niques. Researchers at the Spokane Research Laboratory of the Na¬tional Institute for Occupational Safety and Health (NIOSH) are investigating methods to improve safety during the transport of ore in ore passes. Design criteria and hang-up prevention and remedia¬tion strategies involve studies of the effects of static and dynamic ore and waste-rock loads on chutes, walls, gates and support structures. Particle flow analysis methods were used to simulate the response of various ore pass designs to a wide range of ore loading condi¬tions. A full-scale mockup of ac¬tual ore pass and chute assemblies was duplicated and tested for load response. Data from a particle flow code and the mock-ups were com¬pared Loads on an active ore pass chute were measured.

By John P. Capp

Information is summarized on the major uses of fly ash and prospects for utilization in agriculture and in brick and mineral-wool manufacture. Technological aspects of utilization are discussed and references are given to the work of many of the leaders in the fields of fly ash production, processing, and utilization.

Jan 1, 1970

[COUNCIL FOR 1991/92 President R.D. Beck President Elect JP. Hoffman Vice Presidents Senior Junior Dr H. Scott-Russell J.A. Cruise Immediate Past President Honorary Treasurer H.G. Mosenthal J.A. Cruise Members of Council Dr N.A. Barcza G.A. Brown B.R. Broekman Prof. RJ. Dippenaar B.R. Fleetwood* J.S. Freer P.R. Janisch P.J. Knottenbelt Dr J. Lurie R.P. Mohring *Co-opted K.C. Owen P.D.K. Robinson D.A.J. Ross-Watt P. Smith K.A. van Gessel DJ. van Niekerk P. van Schaardenburgh* CJ.C.J. van Vuuren* P.M.T. White]

Jan 1, 1992

By L. W. Vigrass

Porous and permeable rocks deeply buried in sedimentary basins contain immense volumes of hot water with the potential to supply low-grade heat energy. A part of Canada with sizeable potential for low-grade geothermal energy is the northern Williston Basin of southern Saskatchewan. In this region, the University of Regina has conducted a geological study investigating the feasibility of producing large quantities of warm water suitable for space heating in the Regina - Moose Jaw area. The study has shown that the most favourable geothermal reservoirs are in the Basal Clastic Unit (Cambrian Ordovician), which, at an approximate depth of 2,000 metres has predicted temperatures of 71°C to 74°C. We anticipate sustainable flow rates from these reservoirs of 100 to 300 ms/hr. The water contains about 150,000ppm of total dissolved solids, mostly sodium chloride. It is anticipated that the sulphate content will be 3,000 to 6,000 ppm, that the dissolved oxygen and hydrogen sulphide content will be small, and that the waters will be neutral to slightly alkaline. It is anticipated that the piezometric level will be 46 m below the ground surface for reservoirs in the upper part of the Basal Clastic Unit and 141m below the ground surface for the lower reservoirs of the unit. Plans are to build a low-grade geothermal research, testing and demonstration facility at the University of Regina. To be a practical demonstration, the facility will have to handle very large volumes of water. Because of high salinity, the water will be re injected into a subsurface reservoir. We do not anticipate insurmountable problems because of salinities or as a result of corrosion provided that the waters are not aerated during handling

Jan 1, 1979

By C. B. Davison

One goal of the Bureau of Mines is to conserve the Nation's mineral resources by developing improved performance materials. Consistent with this goal, the Bureau conducted studies on the formation of undesirable cristobalite in seven different fire clays used as refractories. The studies employed scanning electron micrography, chemical and X-ray analyses, and pyrometric cone equivalent determinations to examine the sample clays and determine the effect of thermal history and stablilizing additives on the amount of cristobalite in various calcines. This research has indicated that as fire clay calcining temperatures increased from 1390° to 1,490° C there was a gradual decrease in the percent of cristobalite present in the calcines and a progressive development of mullite crystallization. No cristobalite was found in fire clays calcined above 1,550° C, but cristobalite reappeared when the calcines were reheated to temperatures between 1,400° and 1,500° C. The research also revealed that additions of lithium fluoride (LiF) prevented formation of cristobalite in fire clay calcines.

Jan 1, 1979

By M. A. Trevits, A. Ozmet, A. C. Smith, J. B. Walsh, T. P. Mucho

Improvements in remote fire fighting technology are needed to reduce miner exposure to the dangers of fires and possibly save the lives of those who may become trapped. The National Institute for Occupational Safety and Health, in cooperation with U.S. Foam Technologies, Inc1., conducted a series of experiments at the NIOSH Lake Lynn Experimental Mine to study the stability, transport, control and fire extinguishing effectiveness of nitrogen-enhanced foam technology. This paper presents a description of the mine test configurations and experimental results

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 Arnis Mangolds

A study of the technical and economic feasibility of using a unique undercut and fill system developed by USBM engineers to mine steeply pitching coal is discussed. A brief resource assessment has indicated that significant reserves exist in most coal regions to justify the development of a safe and economical method of extracting steeply pitching coal. The undercut and fill system combines hydraulic coal cutting with unassisted gravity fluming of the coal slurry. Mining occurs across strike and the extended entry is backfilled to provide uniform strata control and an impermeable water and air barrier. Subsequent mining occurs beneath the previously filled stope such that the roof consists of a solid, controlled back. In addition to providing positive roof and hanging-wall support, the backfill system eliminates subsidence potential, post-mining drainage, and the danger of spontaneous combustion from naturally drafting air currents. A unique through-flowing ventilation system permits passage of return air through the production face via ducting located at the backfill-coal junction. This provides a constant supply of fresh air at the face, eliminates the need for brattice cloths, and provides an additional escapeway for the miners. The preliminary estimates indicate a production rate in the neighborhood of 31.9 tons/ manshift. Capital costs are approximately $3.17/raw ton over a 20-year life with an initial investment per annual ton of $48.29. Total cash-costs for labor, supplies, power and benefits range in the vicinity of $19.59 for a 704,460 ton/year mine, or a total cost of $22.76/ton. These costs do not include federal and local taxes or post-of-money; however, the cost of coal is well within the area selling price.

Jan 1, 1981

By E. P. Carman

1. CARMAN, EVERETT P., OPPERMAN, MARTHA, NISHIYANA, SALLY, AND RACOOSIN, LEE. Bibliography of Bureau of Mines Investigations of Coal and Its Products, 1945 to 1950. B. 528, 1954, 60 pp. 40 cents. 2. ROSE, HAROLD J. Industry-Sponsored Coal Research in the United States. Chap. in Proceedings: Fifth International Conference of Directors of Mine Safety Research. B. 489, 1950, pp. 9-12. $1.25. Minerals Yearbook 3. STRINER, HERBERT E., CARMAN, E. P., AND GOODING, RICHARD M. Review of the Mineral-Fuel Industries in 1952. Minerals Yearbook 1952, Fuels, vol. 2 (pub. 1954), pp. 1-28.

Jan 1, 1958

By Carl Hendricks

Aquila Mining Systems Ltd., is the world leader in drill monitoring, control and GPS-based machine navigation systems for the mining industry. This paper will review the design and application of AQUILA’s drill monitoring, control and positioning systems currently in use throughout the world and some of the benefits that derive through their use. In 1993, AQUILA became the first company to install a high precision, cm level, real-time GPS receiver on a blasthole drill. In fact, this was likely the first application of GPS on any form of production mining equipment. To date, AQUILA has installed over 90 GPS based drill monitoring systems worldwide. Since 1992 AQUILA has continued to lead in the advancement of new technologies for drilling including real-time geology recognition and automated drilling control systems. The AQUILA DMseries drill systems offer mines the ability to collect and transmit to the mine office; drill production statistics, ore and waste intersections, exact collar elevations, hole positions and depths, maintenance information and consumables tracking. Unique office software developed by AQUILA provides an encompassing Windows environment within which to manage and coordinate all aspects of data communications and information management between the drills and various mine departments. AQUILA and Caterpillar, along with Mincom and Trimble Navigation are partners in a technology alliance that is providing the surface mining industry with vehicle tracking and navigation systems for all mobile production equipment.

Jan 1, 2000

By W. Wittke, J. Gattermann

ABSTRACT: One alternative to close a radioactive waste repository in rock salt is the construction of a “Cross Section Closure (CSC)“ sealing barrier. The proposed material for the CSC is highly compacted bentonite. To investigate the swelling behaviour of a highly compacted bentonite a large number of laboratory tests were performed. In addition, large scale model test were carried out to demonstrate the development of a nearly homogeneous and isotropic swelling pressure. The results of the large scale model tests were interpreted numerically based on the models for stress-strain behaviour and water uptake which are implemented in the finite element codes FEST03 and HYDOPO. The investigations show a good agreement of the results of the model tests and the corresponding analyses and show, that the theoretical models are capable of describing the behaviour of sealing structures based on highly compacted bentonite. ZUSAMMENFASSUNG: Eine Möglichkeit für den Verschluß eines Endlagers für radioaktive Abfälle im Steinsalz ist die Konstruktion einer Querschnittsabdichtung aus hochverdichtetem Bentonit. Zur Untersuchung des Quellverhaltens von hochverdichtetem Bentonit wurden eine große Anzahl von Laborversuchen durchgeführt. Um die Entwicklung eines nahezu homogenen und isotropen Quelldrucks nachzuweisen, wurden darüber hinaus auch Modellversuche in größerem Maßstab durchgeführt. Die Ergebnisse dieser Modellversuche wurden im Hinblick auf die Wasseraufnahme und das Spannungs-Verformungsverhalten mit Hilfe numerischer Berechnungen mit den finite Element Programmen FEST 03 und HYDOPO interpretiert. Die Untersuchungen zeigen gute Übereinstimmungen zwischen Versuchs- und Berechnungsergebnissen. Die numerischen Modelle sind somit geeignet, das Verhalten von Abdichtungsbauwerken aus hochverdichtetem Bentonit zutreffend zu beschreiben. RÉSUMÉ: Une possibilité pour fermer un dépôt final de déchets radioactifs dans sel gemme est la construction d'un étanchement de coupe transversale, fabriqué de bentonite fortement compacté. Pour étudier le comportement de gonflement de bentonite fortement compacté, de nombreux essais en laboratoire ont été exécutés. En outre, des essais sur modèle sur une plus grande échelle ont aussi été exécutes afin de prouver le développement d'une pression de gonflement à peu près homogène et isotrope. Les résultats de ces essais sur modèle étaient interprétés en vue de l'absorption d'eau et du comportement contraintes-déformations par le moyen de calculs numériques avec les programmes d'éléments finis FEST03 et HYDOPO. Les études montrent de bonnes conformités entre des résultats d'essai et de calcul. Les modèles numériques sont ainsi capables de décrire justement le comportement d'ouvrages d'étanchement fabriqués de bentonite fortement compacté.

Jan 1, 2003

Introduction MINING IS THE BRANCH OF INDUSTRY involving the exploration and removal of minerals from the earth (figure 1). Mining is one of the oldest and most important endeavors of humankind, because it provides the raw ingredients for most of the material world around us and, like agriculture, is the lifeblood of civilization. The main objective of any type of mining is to remove the valuable material economically and safely with minimum damage to the surrounding environment. The Earth has many natural resources on which we depend that must be mined. Coal, oil, gas, and other mineral fuels are used for heating electricity, and numerous industrial processes. Nonfuel minerals such as iron ore, precious metals, and industrial metals, and nonmetallic materials like sodium and potassium are used in chemical and agricultural applications. Even crushed stone used in road building and other construction projects must be mined. Mining affects our standard of living and impacts almost everything we do. A myriad of items that we use in our homes and offices and for transportation, communications, and national defense all require minerals (figure 2). For example, more than 30 different minerals are needed to make a television or telephone! Table 1 lists several commonly mined materials and some of the end uses in our daily lives.

Jan 1, 1995

The amount of liquid retained in a porous bed is determined by weighing a column containing the bed.The column is attached to the free end of a cantilevered beam, and changes in weight are determined by calibrated strain gauges (which form a resistance bridge) attached near the fixed cnd of the beam. By coupling the output from the strain gauges to an amplifier and a recorder, a continuous record of changes in the drainage characteristics of the bed may be obtained.

Jan 1, 1968

By Gary L. Hundley

The Bureau of Mines has devised and demonstrated an ammoniacal sulfate leach process for recovering nickel and cobalt from low-grade domestic laterites. Solvent extraction of cobalt, one of the process steps, requires the reduction of hexammine complexes of C03+ to C02+ in an ammo-niacal leach solution. Previously, reduction was accomplished using cobalt metal shot in a column. This report presents experimental results and an economic evaluation comparing two alternate techniques with the shot column: (1) an electrolytic reduction cell with an extended surface area cathode and (2) direct electrowinning from purified leach solution using a cell with a fluid bed cathode. The second alternative eliminates the conventional solvent extraction-electrowinning steps. The costs of the three methods, based on the requirements of a pro-posed commercial-sized plant, including all unit operations, were deter-mined by the Bureau's process evaluation group. The operating costs for the shot column, $1.19/kg Co, and for electrolytic reduction, $1.20/kg, are essentially the same, but the cost of direct electrowinning, $3.77/ kg Co, would eliminate this method as a practical alternative. The cap-ital cost of approximately $14.4 million for reduction in a shot column is much higher than the approximately $4.4 million for electroreduction.

Jan 1, 1985

By Philip B. Bucky

CONTENTS [PACEPACE r. What Is a Rock Burst?2 4. How Can Rock Bursts Be Predicted? . 35 Jack Spalding2Jack Spalding35 A. F. Robertson 2, 5A. F. Robertson35 W. R. Crane 2A. B. Yates and P. J. Shenon. . . . 35 G. S. Rice 2W. R. Crane 35 P. J. Shenon 2G. S. Rice 35 L. C. Graton 2B. F. Tillson 36 2. What Are the Causes of Rock Bursts? 6 5. How Can Rock Bursts Be Controlled?. 36 Jack Spalding6Jack Spalding36 A. B. Yates and P. J. Shenon . 7, 12, 29A. F. Robertson 36 A. F. Robertson 12, 28W. R. Crane37 W. R. Crane 15A. B. Yates and P. J. Shenon. . . . 37 G. S. Rice 15Oscar Weiss38 Oscar Weiss15G. S. Rice37, 42 P. B. Bucky21R. D. Hoffman42, 43 P. H. Bird 21, 26, 28R. D. Hall 42 M. K. Hubbert26R. H. Cromwell42 G. Wheeler 26. J. Shenon 42 B. F. Tillson26, 28P. B. Bucky42, 44 T. T. Read 27B. F. Tillson 42, 44 A. B. Yates 43, 44 3. How Can Rock Bursts Be Prevented? . 30P. H. Bird 43 Jack Spalding. . . . • . • • • • . 306. General Discussion . A. B. Yates and P. J. Shenon. . . . 31Jack Spalding44 A. F. Robertson32R. D. Parker49 W. R. Crane 35C. Baring Horwood 51 G. S. Rice 35P. B. Bucky 52] FOREWORD THIS symposium brings together points of view, experiences and ideas on rock bursts from a goodly portion of the globe. Some conceptions, particularly those regarding the necessity of depth, have been fairly well shattered, as we find that they are present in the water tunnels of New York, on the surface at marble quarries in Vermont, and in the coal mines of the United States, as well as in the deep mines of the South African and Kolar gold fields, and in the nickel, copper and gold mines of Canada. Their occurrence under such a variety of conditions is, therefore, a challenge,

Jan 1, 1942

ON mineral lease 38 of the Sulphide Corporation Limited, Broken Hill, a shaft was sunk in the early days Ior prospecting purposes and at the present time it is accessible as far as the 1000-ft. level where a connexion exists with the main workings of the Corporation's Central Mine, mineral lease 9. About the year 1895· a crosscut was driven east from this shaft at the 1330-ft. level cutting the Central Ore-body in mineral lease 9 and the shaft is supposed to extend a further depth of 25 ft; but no records of any of this work are in existence, the whole of the evidence being based on hearsay and memory:Fig. 1 shows the position of the Extended shaft in relation to the main workings. The shaft filled with water to the 1000-ft. level where it overflowed through the crosscut to the main shaft and was pumped to the surface, but when the South drive on the 1300-ft. level was pushed to the southern boundary, it was deemed advisable for safety, to tap the water at this level and so relieve the...

Jan 1, 1919

The Skorpion process comprises three processing steps, atmospheric leaching in sulphuric acid, zinc solvent extraction and electrowinning to produce special high grade zinc. The major mode of impurity transfer was attributed to crud runs in the solvent extraction circuit. Crud may be described as a heterogeneous, partly inorganic, partly organic mass of material which accumulates predominantly at the interface between organic and aqueous solutions. The paper describes the route causes of the crud formation in the solvent extraction circuit and optimisation strategies which are being followed to prevent impurity excursions in electrowinning. Keywords: zinc oxide, solvent extraction, crud formation, colloidal silica

Jan 1, 2007