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By Madan M. Singh

The use of fluid jets for industrial purposes has received considerable attention in recent years. The convening of The First International Symposium on Jet Cutting Technology1 in April 1972 devoted solely to this subject probably heralds the coming of age of this new science. It is interesting to note the emphasis in the conference towards the cutting of rocks, minerals, and soils, indicating the attention being devoted to excavation and mining. The use of water streams for mining of minerals is not new. It is well over a century since its first application.2 But its use in coal mining has been somewhat restricted over the years. In the past 30 years the U.S.S.R. has successfully used water for coal extraction, and these techniques have been examined in 15 countries in recent years. In the United States research on various aspects of the method has been conducted for over 15 years,3 but success stories from the Soviet Union,4 JapanS and Canada6 in the last 5 years has spurred greater enthusiasm. IIT Research Institute has done pioneering work in the 7-12 13-15 area of water jetting for rock and coal breakage. It has just completed an experimental study involving mining of coal with a 50,000-psi and 100,000-psi jet in a stripping operation14 under the sponsorhip of the U. S. Bureau of Mines (Contract No. HOll1789). As a complementary program the Bureau initiated a project to design a water-jet coal-mining machine (Contract No. H0133119). IITRI was a successful bidder on this competitive procurement.

Jan 1, 1974

By M Randall, P Ebzery, F Burns, C Aisthorpe, P Blanz

SAG Mill process control classically maintains the SAG mill volumetric filling within a set operating range. Typically a SAG mill weight measurement, by either bearing pressure transducers or load cells, is used as an inferred measurement of volumetric filling. To maintain volumetric filling within a set operating range the SAG weight setpoint use for process control requires regular review due to changes in SAG mill charge density (rock:ball ratio) and the wearing of mill liners. At Lihir Gold Mine in Papua New Guinea, the use of SAG mill weight for process control is additionally complicated by compromised load cells and drifting bearing pressure measurements. The need for an improved method of measuring and controlling volumetric filling led to the recent installation of the Outotec MillSense, a SAG mill toe angle instrument. This paper presents the integration of the toe angle control in to the Lihir SAG mill process control philosophy as replacement for the traditional mill weight control.CITATION:Burns, F, Aisthorpe, C, Blanz, P, Randall, M and Ebzery, P, 2018. Toe angle measurement for SAG mill control at Lihir gold mine, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 59–76 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By L. J. Kane

Applications are described of various methods for determining the weight concentration and physical properties of solid and liquid impurities of gases in connection with problems encountered in synthesis-gas production. Of special interest among these methods may be listed: 1. A method developed for determining, the weight concentration of solid and liquid impurities in. hot, crude synthesis gas containing a high concentration of moisture. 2. A method developed for the same purpose but for highly purified synthesis gas or atmospheric air. 3. A method for obtaining a uniform dispersion of dry duet or, a microscope slide for particle-size determination or other purposes.

Jan 1, 1954

By Yuzura Sato

Viscosity has been measured for various molten binary alloys of nickel with iron, cobalt and chromium in order to clarify the behavior of viscous flow of molten nickel alloys. The entire concentration range for iron and cobalt and 0-67at% of chromium content were studied. The measurement method was an oscillating cup viscometry using an alumina crucible that was precisely machined. The temperature was up to about I 880K for all the measurements. The results represented good Arrhenian relationship although some measurements included overcooled temperatures. The isothermal viscosities increased monotonously with an addition of iron and chromium into nickel. The addition of cobalt increased after stationariness. The isothermal viscosities showed concave curves. Activation energies increased monotonously by adding all the elements into nickel. These phenomena were considered to be related to the thermodynamic properties 'such as the heat of mixing and the structures of mixture melts.

Jan 1, 2003

By T. Glenn Pobanz

For more than fifty years Walter Kidde & Company, Inc. has engaged in the development and manufacturing of both fire suppression and detection equipment. Our initial work for the mining industry centered around dry chemical extinguish-ing equipment for mine haulage cars. To fulfill this need, Kidde engineered and developed a manually activated dry chemical system to provide protection for the wheel wells, cable reels, and motor compartments on various pieces of underground mining equipment. The next phase of mining operation fire protection for Kidde was the area of detection and automatic fire suppression for conveyor belt heads. Early in 1970, a field evaluation program and belt head demonstration unit was taken to 10 areas throughout West Virginia, Kentucky, Pennsylvania, and Ohio. This extensive field program was a joint effort with National Mine Service Company of Pittsburgh, Pennsylvania. The objectives of this program were to study mine hazard problems and to determine further requirements of mine operators. The resulting belt head detection system centered around our Continuous Strip Thermistor Core heat detector in conjunction with a Kidde stored pressure dry chemical extinguishing system. Continuous Strip detection has been in use for a number of years in aerospace applications. It has proven flexible and reliable for the rapid detection of overheat conditions and fires in engines of over half the aircraft flying today. The use of Continuous Strip gave us flexibility to protect surface areas over and around the actual conveyor belt head equipment. The nature of Continuous Strip allows us to bend, wrap, and attach the 20 foot long thermistor element over the desired protected points of the belt head. An integral part of the conveyor belt head protection system is the control panel utilizing our comprehensive knowledge of fire alarm control logic. This panel contains supervision circuits which sound trouble signals upon detecting a break in the Continuous Strip; breaks in the wiring to the remote electrical extinguishing activators or to the alarm bell; or loss of primary power. A separate control module provides the adjustable alarm temperature setting of the

Jan 1, 1971

By Chas. G. Maier

The absence of plants on the Pacific coast for the reduction of iron ores usually is attributed to the fuel situation there. Thus, the bulletin of the. State Division of Mines for 1933, entitled "California Mineral Production," says: "There are considerable deposits of iron ore known in California, notably in Shasta, Mad era, Placer, Riverside, San Bernardino, and Los Angeles Counties, but production has so far been limited for lack of an economic supply of coking coal." It has been estimated that the six major steel plants of the Pacific coast have an annual ingot capacity of 600,000 tons. The present need for tin plate averages 300,000 tons yearly for California alone, of which some 12 percent is manufactured locally. If the consump¬tion of other iron and steel products in 1929 may be taken as an approximate, estimate of the normal requirement for such products, it may be estimated further that, 65,000 to 75,000 tons each of cast-iron pipe and steel reinforcing bars and 300,000 to 400,000 tons of structural shapes and plates will be required annually in California.

Jan 1, 1936

An accelerated and coordinated program of coal research is believed by many to be a necessary step in assuring coal's proper position in the expanding energy market. The President's Advisory Committee on Energy Supplies and Resources Policy, for example, made the following recommendation: We recognize that coal is a great national asset and endorse a cooperative study to determine what research and development could be undertaken. The coal industry and both Federal and State Governments should participate in this study and its costs. Representatives of the coal industry have agreed that such a study should be initiated. Accordingly, Felix E. Wormser, Assistant Secretary - Mineral Resources, United States Department of the Interior, requested the Bureau of Mines and Bituminous Coal Research, Inc., to conduct a survey of current research on bituminous coal. In addition to this survey, studies were made to determine research projects that would be of value to the coal industry.

Jan 1, 1956

By Walter W. Kaufman

This User's Manual, extracted from information contained in the Final Report for the above referenced project, outlines test procedures to measure the braking capabilities of underground non-coal rubber-tired mining equipment. Methods to interpret test results, recommendations for safe braking capabilities, and basic techniques to improve braking systems and road surfaces are also discussed. Possible applications for runaway vehicle protective devices other than braking systems are reviewed. Also included is a listing of mining equipment and brake component manufacturers who supply the majority of equipment to the United States non-coal mining industry. In conjunction with this list of manufacturers, a general tabulation of brake related specifications appears for vehicles observed during stopping tests conducted underground.

Jan 1, 1977

By T. E. Green, E. F. Spano, W. J. Campbell

A combined ion - exchange X- ray spectrographic method was developed and evaluated for determining trace amounts of cobalt and nickel in high - purity tungsten and tungsten trioxide . The sensitivity for both cobalt and nickel is in the range from 0.2 to 0.5 μg ( 0.04 to 0.1 ppm , based on 5 gram samples ) . Accuracy at the 5 to 20 μg level is ±10 percent of the amount present . Approximately 16 hours elapsed time is required for analysis

Jan 1, 1963

By W. T. Westbrook

This Bureau of Mines report contains methods for analyzing iron are for total iron, ferrous iron, metallic iron, silica, manganese, aluminum, calcium, magnesium, phosphorus, titanium, carbon, sulfur, moisture loss, and ignition loss by wet chemical methods. Some are modifications of standard umpire methods; others have been developed by the Bureau of Mines to provide a com-bination of speed and accuracy. They are suitable for a high volume of samples and/or control situations, and for situations in which instrumental results must be verified. These methods have been used to analyze taconites, native ores, some foreign ores, and metallurgical products.

Jan 1, 1975

By M. D. Aldridge

The results of a four-year research effort aimed at developing a practical and effective electronic system for monitoring safety conditions throughout a coal mine by displaying, at a central location, remotely measured parameters are described. This document reports on the design details of the sensor packages and the data processing program used in an experimental monitoring system. The results of special ventilation monitoring experiments and several sub-system considerations are also described.

Jan 1, 1974

By Frederick W. Lee

List of contributing editors of Geophysical Abstracts:

Sep 1, 1932

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. A senior advisory staff, consisting of the Chief Staff Officer, Chief Scientist, and Chief Mining Engineer, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaisons with other government agencies, mineral industries, and professional societies. Bureau program activities are classified into two major functions: (1) Developing new and improved technology that will make the production and processing of minerals more efficient, safer and more healthful for mineral workers and the public, and more compatible with a quality environment.

Jan 1, 1980

By A. H. Rhoades

The modern polarizing microscope with such accessories as cameras, infrared devices, reflectance and/or transmission photometers, indention hardness, and heating stage is used to characterize coal, coke, and other carbon forms. It allows characterization of coke by-products, such as tars and pitches and their insoluble residues. A useful product of the microscopic approach is the coal petrographic analysis which permits the prediction of coke strength carbonization pressure and volume change. Carbonization tests are expensive, time-consuming and require large amounts of coal. Tests on the coke show it to be strong or weak but give no indication of why. Petrographic analysis requires grams of coal and yields data that indicates why the coal produces coke of a given quality. Small samples from drill cores are sufficient for petrographic analysis. These data are also used to optimize blends for coke production. When coke-plant problems occur, ~he microscope can be used to check the coal blend proportions, as well as for weathered coal. Microscopy is useful in spore correlation work which may be a prerequisite to sound coal reserve estimates. Dispersed vitrinoid reflectance studies are used to determine the degree of organic metamorphism which serves to establish oil and gas deadlines. Tars and pitches are examined microscopically for the amount of normal solids as well as the size of undesirable carry-over solids resulting from pollution abatement practices in coke works. The microscope is also used to study coals for gasification and liquefaction.

Jan 1, 1981

By P. E. Cavanagh

Abstract Many investigators have been interested in developing some non-destructive method for detecting or determining the changes in physical properties in steel occurring during endurance tests or normal service life of a part which fails in fatigue. This paper presents a broad discussion of some of this work and the possibilities of developing useful test procedures based on some of the information obtained in the past. Changes in magnetic properties, electrical resistance, damping capacity, X-ray diffraction patterns, and remaining fatigue life at load different from service load have all been investigated as possible means for following the sequence of events during fatigue failure. In some special instances, tests such as these may be used to predict fatigue failure. As an in stance of practical application of the continuous determination of changes in magnetic properties during fatigue, a brief account is given of work done in non-destructive inspection of mine hoist-rope. As a result of extensive experiments and field crisis, it has been found possible to detect the beginnings of failure in a wire rope in service. The test method used will detect plastic deformation in a wire rope, no matter what its cause. There is no possibility of determining the remaining useful life of a rope by calibrating changes in magnetic properties in terms of remaining fatigue life. A change in magnetic properties at a point in a rope may indicate a decrease or increase in fatigue life, depending on the overload history of the rope. A continuing change in magnetic properties ac a point, however, does reliably indicate a developing weak point which will eventually lead to failure. The important point about any change in magnetic properties is not the magnitude of the change, but whether or not it continues.

Jan 1, 1947

By R. A. Hatch

This report summarizes the results of nearly 8 years research on and production of synthetic mica at the Electrotechnical Experiment Station of the Federal Bureau of Mines, Norris, Tenn. This program was undertaken at the request of the United States Department of the Navy and was financed mostly by the Army Signal Corps and the Navy Bureau of Ships through a contract with the Office of Naval Research, The original objectives included fundamental studies of fluor-phlogupite and other fluorine-micas and production of synthetic mica sheets on a pilot-plant scale. The first 3 years of this project were devoted mainly to a search for practical solutions of the many problems involved in designing and constructing a pilot plant for crystallizing fluor-phlogopite mica. The first and most urgent need was a suitable container for the corrosive mica melt. After extensive study, it was concluded that platinum, graphite, high-silica fire clay, and silicon carbide were the most promising refractories for crucibles; but none was perfect. Silicon car¬bide seemed to have the better combination of qualities, combining good corrosion resistance with oxidation resistance.

Jan 1, 1957

By John S. Ball

Aniline points have been used to some extent for more than 20 years. to indicate the types of structures in hydrocarbons and thus to analyze mixtures of hydrocarbons . This type of analysis has been applied - principally to the low -boiling hydrocarbons found in the gasoline range . Although there is some disagreement as to their merits , both aniline point and diesel index (aniline point in degrees Fahrenheit times A.P.I. gravity at 60 ° F. divided by 100) are used rather extensively for evaluating ignition qualities of diesel fuels . In recent years aniline points have been employed in the study of lubricating - oil fractions . They also have been used to predict : the tendency of different oils to cause swelling of synthetic rubbers.5/ Recent standardization of the aniline - point determination by the American Society for Testing Materials has encouraged wider use of this test . Considerable data concerning , aniline points and critical solution temperatures in aniline have been accumulated in the course of a study of related subjects . Thesc data , together with some original results , are presented here in the hope that they will prove useful to other worker's in this field ...

Oct 1, 1943

By JOHN BUZARD

In the following pages the writer has endeavored to give an account of the many methods, advantages, and disadvantages of preparing and burning powdered coal. For much of the information jmparted the writer is indebted to various firms in the United States and Canada whose plants he visited, also to the technical press. Manufacturers and operators of coal-fired furnaces can not afford to disregard the possible advantages of pulverizing their coal before burning it. Hence the purpose of this bulletin will be fulfilled if it leads them, after making careful estimates, either to abandon their present method of burning cGal on grates or stokers, and install the pulverizers, conveying system, powdered-coal feeder, and burner best suited for burning powdered coal in their plant, or to reject, as uneconomical, the replacement of their present system of burning coal by a system for pulverizing and burning it. No research work on the combustion of powdered Canadian fuels has been carried out by the Mines Branch, Department of Mines; but if this research work were carried out scientifically by competent engineers, chemists, and physicists, it would show how powderedcoal furnaces and burners should be designed to gi ve an efficiency higher than they give at present.

Jan 1, 1923

By Yuzuru Sato

Viscosity has been measured for various molten binary alloys of nickel with iron, cobalt and chromium in order to clarify the behavior of viscous flow of molten nickel alloys. The entire concentration range for iron and cobalt and 0-67at% of chromium content were studied. The measurement method was an oscillating cup viscometry using an alumina crucible that was precisely machined. The temperature was up to about 1880K for all the measurements. The results represented good Arrhenian relationship although some measurements included overcooled temperatures. The isothermal viscosities increased monotonously with an addition of iron and chromium into nickel. The addition of cobalt increased after stationariness. The isothermal viscosities showed concave curves. Activation energies increased monotonously by adding all the elements into nickel. These phenomena were considered to be related to the thermodynamic properties such as the heat of mixing and the structures of mixture melts.

Jan 1, 2003

By A. Anderko, V. G. Papangelakis, G. Moldoveanu, G. Azimi, M. Carlos

"OLI Analyzer is a software package that uses the powerful Mixed Solvent Electrolyte (MSE) model to simulate the behavior of multicomponent electrolyte solutions from infinite dilution to the limit of fused salt, and from temperatures below the freezing point up to near critical temperature of the mixture. The software also allows the creation of thermodynamic parameters for new chemical systems unavailable yet in public-domain or commercial software databanks. This communication reviews the basics of the model and provides some examples of modeling hydrometallurgical applications with emphasis on high temperature applications, including calcium sulfate scale formation in autoclaves, high temperature pH inference and iron control. INTRODUCTIONModeling of electrolyte systems has been of particular interest to various industrial processes, such as separation processes (e.g., solution crystallization, extractive distillation, seawater desalination or bio-separations), environmental applications (e.g., gas treatment, wastewater treatment or chemical waste disposal) and hydrometallurgy (e.g., pH control and neutralization, iron control, scaling and fouling of equipment). Using a chemical model, time-effective predictions of various properties of electrolytes can be obtained, which is beneficial not only during process monitoring, but also during process optimization and process scale up. As a result, pilot scale studies can sometimes be eliminated where budgetary constraints exist. Development of such a powerful model requires the use of a speciation-based model, in which solution chemistry is explicitly addressed (as compared with some models that treat electrolytes either as undissociated or fully dissociated systems), despite being computationally challenging. In addition, as a feature of electrolyte systems, speciation equilibria inherently influence the phase equilibria due to complex formation, ion pairing, and acid-base reactions. Therefore, how the electrolyte solutions behave at various conditions may differ significantly due to the non-ideality, which must be carefully addressed to obtain a model that is applicable to a wide range of conditions such as concentration, temperature, pressure and solvent system."

Jan 1, 2012