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By William A. Beck

"In 1912 bauxite was discovered in the Andersonville district, which lies in the 28th and 29th land districts of Georgia and comprises parts of Sumter, Macon, and Schley Counties. Mining was begun in May 1914 by the Republic Mining & Manufacturing Co. Considerable ore has been produced in this region since that time by individual interests and by the American Cyanamid & Chemical Corp., which acquired the property formerly owned by the Republic Co.The area was examined in the fall of 1941 by representatives of the Bureau of Mines and the Geological Survey, after which a prospecting program was begun by the Bureau. Drilling was started on December 26, 1941, and continued until November 18, 1943. A total of 1,192 holes was drilled in the district, and 3,679 samples were taken and analyzed.Mineral exploration agreements were signed by 146 property owners covering 42,128 acres. Holes were drilled on 121 of these properties, which have a total area of 38,778 acres.Drilling under this project disclosed several new deposits, of which four have been completely delimited. Previous prospecting in this area by mining companies did not find bauxite, as it lies under heavy overburden. Work by the Bureau indicates 14,412,000 long tons of ore containing 30 percent or more alumina. The total tonnage is divided as follows:Georgia State Highway Routes 26 and 4-9 traverse the district. The Central of Georgia Railroad passes through the center of the entire district (see fig. 1).The project was initiated by J. R. Thoenen, supervising engineer, Non-metals Mining Section, Mining Division, Bureau of Mines. It was under his general supervision until July 1942, after which it was under the general supervision of E. J. Lintner and Rowe McCrae, district engineers for Georgia, South Carolina, and Flordia, respectively.John C. Feeley, Jr., was project engineer from December 1941 to April 1942. Other engineers who assisted in the work on the project are R. E. Babcock, T. M. Romslo, Don M. Coulter, and Walter T. Lewiecki.Acknowledgment is due the metallurgical staffs at College Park, Md., and Tuscaloosa, Ala., for analyses of samples and beneficiation tests.Acknowledgment is also expressed to Alfred D. Zapp, M. W. Harris, Elmer Kneedler,and Parke D. Snavely, of the United States Geological Survey, for their aid, data, and maps.Bauxite was discovered in the Andersonville district in 1912 on lot 187 of the 28th land district, in Sumter County. This lot is situated about 1.5 miles west of the Flint River, on the south slope of the valley of Sweetwater Creek. Mining was started in May 1914 by the Republic Mining & Manufacturing Co. This and adjacent properties were acquired in 1930 by the American Cyanamid & Chemical Corp., which has been operating there since."

Dec 1, 1949

By L Singheiser, W. Willenborg, M. Mueller, K. Hilpert

The limitation of fossil fuel resources and the necessity of reducing CO2emission require an increase of the efficiency of power plants by using combined cycle power systems. Pressurized Pulverized Coal Combustion (PPCC) is a potential concept to realise these objectives. The direct use of hot flue gas for driving a gas turbine requires a hot gas cleanup to achieve corrosion prevention of the turbine blading. One of the main problems is the alkali release during the coal combustion process. Molten coal ash slag has a high potential for alkali retention which depend son the alkali oxide activity in the slag. Knudsen Effusion Mass Spectrometry (KEMS) was used to determine thermodynamic data of alkali gas species over molten coal ash slags and of alkali oxides in molten coal ash slags. The main interest of the investigations focused on the structural dependence of the thermodynamic properties of the alkalis. It was found that there is a strong correlation between the thermodynamic properties and the ratio of nonbridging oxygen to tetrahedral oxygen (NBO/T). An increase of the polymerization of the slag results in a decrease of the alkali oxide activity in the slag and thus a decrease of the alkali partial pressure over the slag. Keywords: coal ash slag, structure, alkali oxide activity, alkali vapour pressure, PPCC, KEMS.

Jan 1, 2004

By F. Sillers, R. T. C. Rasmussen

"INTRODUCTION This is the third report of investigations by the Bureau of Mines in cooperation with industry to establish the value of electrolytic manganese in the manufacture of ferrous and nonferrous alloys. The manganese was produced by the Bureau at its Boulder City pilot plant from domestic ores and by the process developed by it. 4/ The work was done under the direction of R.S. Dean, assistant director, Bureau of Mines, and R. G. Knickerbocker, chief, metallurgical branch. The first report dealt with the use of electrolytic manganese in the manufacture of stainless steels 5/ and the second with its use in acid electric or open-hearth low- and medium-carbon steel castings. 6/The present report treats of the use of electrolytic manganese in the manufacture of low—carbon rimmed and killed steels. A résumé of these three investigations and two others appeared in the magazine STEEL. 7/ Further reports will be published as tests are completed at some 70 industrial plants. All tests were made on full—scale heats or melts, and the resultant product was processed and used commercially."

Jul 1, 1945

"Rock falls involving a relatively small amount of material are a leading cause ofinjuries in underground mines in the United States. A contributing factor is unwantedblast damage and over-break. A goal of the United States National Institute forOccupational Safety and Health is to reduce the number of ground fall-related accidents by improving drift driving practices through the introduction of perimeter control blast designs. This paper presents a blast design technique based on a hydrodynamic method. Using commonly available explosive and geometry data, the theoretical particle velocity is calculated as a function of distance away from a cylindrical charge. A calibration factor is introduced to account for actual conditions by comparing the predicted values to a set of field data. The calibrated curve can then be applied for design. The paper introduces modifications to account for different explosives from those used in a calibration test. The application of the approach is demonstrated with respect to a data set from a large-scale concrete block test."

Jan 1, 2009

By Steven C. Goddard

Since the passage of the Federal Coal Mine Health and Safety Act of 1969, the need for improved duet control methods has become imperative. It has been proposed that one promising dust control technique would be the application of water through the cutter drum. In November of 1972, the Jeffrey Mining Machinery Co., who had been pursuing the development of wet drum miners since 1969, completed the manufacture of a 120M HELIMINER which had sprays in front of the cutting bits on a fixed width drum. On June 27, 1973 Jeffrey and the Bureau of Mines signed the contract numbered B0232060 for the purpose of evaluating "the effectiveness of respirable dust control on a Jeffrey 120M HELIMINER by use of water piped through the head." This evaluation, as described by the contract, was to be accomplished by the collection and analysis of dust samples at various locations of an operating mine production section.

Jan 1, 1974

By N. Gatelier, T. You, J. C. Kandel

ABSTRACT: Underground hydrocarbons storage is a very specific domain for the designer. He is usually free to adjust the section, shape and layout to cope with the geological and geotechnical conditions. This paper presents a panorama of the geotechnical design of mined underground storage caverns, then lists a number of uncommon features encountered in a storage excavated in Sydney, Australia, the Elgas LPG project that had to face major non-isotropic conditions with numerous local variations, impacting on the achievement of the design profiles. Changes in geotechnical design methodology and practice are examined through this project, now in operation, which will have lasted altogether almost ten years. KEY WORDS: underground storage, geotechnical engineering, stability, methodology, design. ZUSAMMENFASSUNG: Die untertaegige Speicherung von Kohlenwasserstoffen unterliegt in der Planung sehr spezifischen Bedingungen. Der planende Ingenieur hat bei der Dimensionierung und Formgebung der Speicherhohlraeume gewisse Freiheiten, muss jedoch vorgefundene geologische und geotechnische Bedingungen beruecksichtigen. Der vorliegende Beitrag gibt zunaechst einen allgemeinen Ueberblick ueber die geotechnische Planung von bergmaennisch aufgefahrenen Speicherhhohlraeumen. Darueber hinaus werden Besonderheiten betrachtet, mit denen das Elgas LPG-Speicherprojekt in einer bergmaennisch aufgefahrenen Kaverne in Sydney, Australien konfrontiert war. Hierbei ging es um die Beruecksichtigung anisotroper Bedingungen mit zusaetzlichen Heterogenitaeten im Gestein und den daraus erwachsenden Schwierigkeiten, die geplante Hohlraumform zu verwirklichen. Ueber einen Zeitraum von fast 10 Jahren, in denen das jetzt in Betrieb befindliche Projekt unterschiedliche Betriebsphasen durchlaufen hat, wurden verschiedene geotechnische Entwurfsverfahren auf ihre Anwendbarkeit geprueft. SCHLUESSELWOERTER: Untergrundspeicherung, Geotechnik, Stabilitaet, Entwurfsverfahren, Planung. RESUME : Le stockage souterrain d’hydrocarbures est un domaine très spécifique pour le concepteur, car celui-ci dispose d'une large liberté pour adapter les sections, les formes et les implantations aux conditions géologiques et géotechniques de l’environnement choisi. Après un panorama de la conception géotechnique des stockages souterrains d’hydrocarbures par la méthode dite des cavités minées, l’accent sera mis sur un certain nombre de particularités rencontrées lors du projet de stockage de GPL de Elgas à Sydney en Australie, creusé dans de très fortes conditions d’anisotropie du massif rocheux, avec de nombreuses variations locales et toutes les implications que cela peut avoir sur le maintien des formes. L’évolution des approches méthodologiques géotechniques durant la dizaine d'années de développement de ce projet depuis les premières études jusqu'à l'exploitation actuelle est également présentée. MOTS-CLEFS : stockage souterrain, géotechnique, stabilité, méthode, conception.

Jan 1, 2003

By Johnson N. W

After an unsuccessful transfer from the laboratory to the pilot plant of galena flotation technology which used sodium metabisulphite and ethyl xanthate, laboratory flotation tests were conducted to identify any unusual variables which had a deleterious effect on the position of the lead rougher grade recovery curve for Hilton and Mount Isa silver-lead-zinc ores. Two variables (pulp temperature and contact time for ethyl xanthate and sodium metabisulphite) had important deleterious effects.The findings allowed a successful transfer of the laboratory process to a pilot plant scale process. The effect of temperature was important because the higher temperature (40°C) in the pilot plant pulp increased significantly the rate of reaction between ethyl xanthate and sodium metabisulphite. In the laboratory process at 20 to 25°C, the reaction rate was lower and did not interfere significantly with the process. The contact time for the two reagents was also important in the pilot plant scale process because of the higher reaction rate at 40°C.To employ ethyl xanthate in the pilot plant process, special precautions were required. Further, a collector (Aerofloat 241) from the dithiophosphate family was used successfully in the pilot plant process.

Jan 1, 1988

By P. Zhang

Previous studies have shown that separation of clay minerals from non-clay minerals is the key to economic recovery of the phosphate from the waste phosphatic clays (slime) which represent about 20- 300/0 of the phosphate mined. Small hydrocyclones of different sizes (4" and 6") were tested for sizing the slime at +10 microns in order to remove most of the clay minerals. The effect of design variables and operating parameters were evaluated. Multi-stage cycloning and the effect of dispersant were also investigated. Chemical and mineralogical analyses of different size fractions of both the underflow and overflow samples indicated satisfactorily separation efficiency.

Jan 1, 1998

By P Cameron

MetPlant conferences have focused on ensuring mining projects are well designed then optimised to operate safely and effectively at the top end of world’s best practice to ensure shareholders are not just happy but delighted. This assumes the MetPlant was built right the first time. However, reality is, too often Plant Metallurgists (PlantMets) find after commissioning they are faced with the expensive task of correcting errors or modifying shortcomings to achieve product quality at name-plate capacity, i.e. get it right the second time. Why do companies spend good money to engineer an excellent feasibility study then allow “wise men” remote from the project team to impose cuts in budget and schedule, often under the guise of value engineering? Since mining is full of uncertainties, such actions can increase the risks of failure with the result that some MetPlants do not work well. Can PlantMets influence the remote wise men who often are also imposing the rules for lending and the required returns to appreciate the uncertainties of mining and their associated risks then let the project team get it right the first time? PlantMets can negotiate with the wise men from the outset of the project and bring them into an outer layer of the team where they can understand the risks then share responsibility and accountability to achieve the common goal of building a MetPlant which works well the first time and deliver the forecast profits. Since shareholders are not in the business to make losses they appoint a Board of Directors to deliver the best outcomes for the shareholders. Thus the Board should seek effective advice on the risk reward implications from the PlantMet before making their decisions.CITATION:Cameron, P, 2015. Do all metplants work well? PlantMets can ensure they do, in Proceedings MetPlant 2015, pp 2–9 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By W. T. Benson

The Bureau of Mines has examined selected deposits of titanium minerals throughout the United States. The titaniferous magnetite deposits in the western San Gabriel Mountains, Los Angeles County, Calif., were among those selected for study, and in 1956-58 field work was conducted to determine the extent and character of the titaniferous magnetite deposits occurring in the area. This report describes this work and summarizes earlier work in the area by the Bureau and others. The titaniferous magnetite occurs disseminated as seams and lenticular pods in an anorthosite belt 4 to 6 miles wide that trends about. N. 80° W., extending from sec. 13, T. 3 N., R. 12 W., to the west boundary of R. 14 W., at which point the titaniferous magnetite-bearing rocks disappear beneath the sediments in the Santa Clara River Valley.

Jan 1, 1962

By Keith R. Vining

Solid fuel, usually coke or anthracite, is commonly added to ground iron ore fines in the pelletising process to reduce the amount of burner fuel required and the maximum firing temperature, while maintaining pellet strength and the productivity of the pelletising plant. However, the use of coke and coal contribute to the production of greenhouse gases (eg carbon dioxide) and are a source of NOx and SOx emissions. Utilising wood biomass / wood char is one methodology CSIRO Minerals is investigating as an alternative to coke and coal, as it is a renewable energy source that is very reactive, has a low ash content and the potential to reduce emissions of greenhouse gases from the iron and steel-making process. Previous work has established that charcoal can effectively replace coke in the sintering process (Lovel et al, 2005), and the following experimental work aims to demonstrate that it can also provide an adequate replacement for coke and coal in the pelletising process. The paper presents the results of an experimental testwork program comparing the behaviour of fired pellets containing traditional solid fuels and charcoal. The physical properties of the pellets are compared in terms of their compressive strength, tumble and abrasion indices and the reduction properties. A qualitative assessment of the pellet microstructures is also presented.

May 1, 2007

Since the comprehensive review of the Persian fields presented by Sir John Cadman last year, operations have proceeded normally. No developments of especial importance fall to be recorded and it remains only to bring up to date the full information given at the beginning of 1933. Controlled production from the Masjid-i-Sulaiman and Haft Kel fields has been maintained at slightly higher rates than during 1932. The figures for the past five years are as follows: These represent crude oil and products piped to the coast but exclude products reinjected into the reservoir, a process that has been in continuous operation at Masjid-i-Sulaiman during the period under review. The systematic delimitation of the Haft Kel field has been continued during the past year and results have been sufficiently encouraging to justify the inception of a wider scheme for distribution of production. Drilling has been resumed recently in the Persian sector of the Naft Khaneh field, and preliminary survey work is in progress for the selection of a site for a refinery at Kermanshah arid the construction of a connecting pipe line. Investigations in connection with the scientific control of reservoir were dealt with in considerable detail in last year's review. This work has been steadily pursued during 1933 and certain of the investigations have been the subject of papers presented to the World Petroleum Congress held in London in July of last year.

Jan 1, 1934

By Ralph B. Youtz

This paper describing mining methods at, the Eighty-Five mine of the Calumet and Arizona Mining Co., Valedon, N. Mex., is one of a series being prepared by the United States Bureau of Mines on mining methods, practices, and costs in the various mining districts in the United States. The Eighty-Five mine is in southwestern New Mexico, 3 miles southwest of Lordsburg, Hidalgo County (see fig. 1). The mine produces normally 7,000 to 8,000 tons per. month of silicious copper-gold-silver ore, and employs approximately 200 men underground and 40 on-the surface. Mining is done by shrinkage and cut-and-fill methods.

Jan 1, 1931

By A. L. Engel

This report is a compilation of results of preliminary tests on scheelite (tungsten) ores and tailings. These investigations were made to assist in establishing satisfactory treatment methods for small-scale concentrator operations, or to indicate a. method for conserving previously lost mineral values in old tailings, if possible. A discussion of test procedures is included, as it was felt that this would add to understanding the results reported under the several projects. The treatment of scheelite ores has become more or less standardized. Important differences occur in textures of ores from various mining districts. However, and this must be considered when planning ore-dressing operations. In most of the present investigations, only a limited amount of work was done, usually just enough to answer a specific question in regard to a particular ore or concerning local conditions. Two methods of treatment included gravity concentration, magnetic separation, and flotation.

Jan 1, 1952

By Emory Smith

The Victorville cement plant of the Southwestern Portland Cement Co. is located about 1 mile from the city of Victorville, Calif. Two transcontinental railway systems, the Atchison, Topeka & Santa Fe, and the Southern Pacific Railroad, afford shipped facilities. The plant is modern and well kept, as the officials, especially the higher operating officials, take pride in the appearance of the place. Dust has been practically eliminated by the installation of dust collectors and wet grinding. The plant has a rated capacity of 5,000 barrels of cement daily.

Jan 1, 1929

By D. Harrington, W. J. Fene

For nearly 30 years the Bureau of Mines has contended that mine explosions can be prevented and has pointed out to the industry ways and means by which they could be avoided. The record of co2l-mine explosions • during the past fiscal ?Bar bears out the :Bureau1s contention, inasmuch as fewer men were killed by coal-mi~e e:xplosions in the United States during that year than in :gi_y corresponding 12 months in the history of coal mining in the United States, insofar as records are available; and more than a year has elapsed since·a major explosion (in which five or more men were killed) has occurred, this being t.1-J.e first continuous 12- month period without a major coal-mine explosion disaster in the United States in more than 60 years. The methods of preventing mine e:iiplosions are well known to experienced, well-informed persons cngnged in coal mining. Despite this knowledge, many coal-mine operutors continue to use practices and methods that they should know have resulted in countless explosions, and mine workers persist in following past procedure or in breaking safety rules and practices almost certain eventually to result in disaster. ' Virtually all explosions are the result of human failure, such as carelessness or neglect by officials or workers or others. These human failures can be corrected chiefly by ed.ucation and proper and adequate supervision and strict discipline. In some instances mine officials are ·lax, careless, poorl~• informed, and often incompetent; end in many instances miners have repulsed the introduction of known preventive methods because of sheer obstinacy, ignorance, heedlessness, or possibly fear that the operator was trying to o'bta.in some unfair adva.,.'1. tago or would neglect some other phase of accident or e,:plosion prevention. The freedom of the fiscal year 1938-39 from major coal-mine explosions ar..d frora any considera~le number of fat,JJ.i ties from minor explosions is a. matter for congratulation, but on the other hand. the occurrence of one rather bad e~losion in each of tho 3 calendar years 1937

Nov 1, 1939

By Nan Wang

Based on the commercial computational fluid dynamics software, Fluent, the fluid flow and temperature field in an iron-bath reactor were simulated numerically, and the effects of top-blown and side-blown operating parameters on the mixing time of iron bath, distribution range of oxygen in top space, and post-combustion ratio were investigated. The simulated results showed that the mixing time of iron bath increased initially and then decreased with the increase of inclined degree and immersion depth of side-blown lance. The distribution range of oxygen became wider as pulling the top lance away from the iron bath. Furthermore, post-combustion ratio was reduced given the top lance was too close the bath. The simulation results provide theoretical base for the process optimization of iron-bath reactor and further development of new type iron-bath smelting reduction process.

Jan 1, 2009

By Mohsen Sanai, Paul Gefken

"SRI International has developed and patented* a castable dilute explosive tile @ET) that offersunique advantages over conventional high explosive. The primary advantages of DET are that itsdetonation pressure can be adjusted over a wick range and its impulse can be controlled independently by adjusting its thickness and configuration. Because DET has a much lower detonation velocity than conventional explosives, the pulse duration produced by DET is as much as 10 times longer than the pulse duration produced by conventional explosives for equal explosive weights. These features of DET present several advantages to the mining industry. For example, DET can be tailored so as to control fragment size and distribution to enhance extraction of desired elements from ore or breakup of specific regions."

Jan 1, 1995

The Reefton Goldfield on the West Coast of the South Island of New Zealand was a significant gold producing area between 1860 and 1951. During this period it produced approximately 2.1 million ounces (67 tonnes) of gold. The largest single producer on the goldfield and the deepest mine in New Zealand, was the Blackwater Mine at Waiuta which produced 21 tonnes of gold. The Prolubition Shaft reached a depth of 878 metres (317 metres below sea level). The mine closed suddenly in 1951 with about 66 000 tonnes of are remaining in the stapes. Since closure there has been no attempt to determine the ore potential of the mine at depth. This paper summarises the geology, history and resource potential of the mine and sets out two options for evaluating the remaining resource. The options are either deep drilling from surface or recovery of the Prohibition Shaft and underground development and drilling. A schedule for each option is presented and discussed.

Jan 1, 1992

By Rob Famlield, Gavin Yuill, William Birch

The Blasting Research Group at the University of Leeds, in the United Kingdom, continues to be highly active in the area of the environmental impact of blasting. In recent years a major part of this research has been concerned with the use of linear superposition. This technique relies upon the assumption that all the holes in a blast produce identical vibration signals. Previous work at the University has shown that this assumption is not sufficiently robust to be generally applicable. This is due to a number of factors of which the key variable appears to be dynamic confinement

Jan 1, 2002