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By Duane L. Abata

This work, conducted under Bureau of Mines contract, deals with the development of a computer graphics software package that will: 1. display mine ventilation schematics and other representative Illustrations for a real-time data acquisition system under development by the Bureau, and, 2. utilize the Bureau-owned Minefire and Ventilation Code for display of ventilation on and contamination predictions. The software package has been written try operate on a 64K, Z-80 based microprocessor-computer. The project has been divided into two phases. The first phase dealt with the development of the graphics software The sec rind phase dealt with the retrofit of the Minefire and Ventilation Code to the Z-80 microprocessor-computer.

Jan 1, 1984

By M. Shamsuddin

Information on total estimated uranium reserves and domestic requirements have been collected, A survey has been made on the possibilities of recovery of uranium from low grade and complex ore deposits, e.g., marine phosphorites, shales, coal, sea water, etc. In order to assess the potential for uranium recovery from uraniferous phosphorites, available thermodynamic data of uranium minerals, compounds and aqueous species have been collected. The existence of uranium complexes with chloride, fluoride, carbonate, phosphate, sulfate, etc., in ground waters have been evaluated at different pH's. There seems a great need to study the relative stability of these complexes in order to judge the applicability of solution mining technology for selective leaching of uranium from phosphorites. A typical flow-sheet demonstrating recovery of uranium from wet-process phosphoric acid has been included in this report. Some essential features of the economics of uranium recovery from uraniferous phosphorites have been briefly considered and recommendation have been made for further studies.

Jan 1, 1980

By S. J. Gasior

Pilot plant studies showed the technical feasibility of fluidized-bed operation for producing hydrogen and synthesis gas by the steam-iron process. A mixture of iron and iron oxide from 20-to 100-mesh was partially reduced with a simulated producer gas and then oxidized with steam and/or carbon dioxide. Results of tests show the effects of pressure, temperature, bed height, gas-to-solids ratio, type of iron oxide, and composition of gas on the gas and solids conversions during reduction and oxidation. A baffled free-fall solids system was also found operable. The short residence time of about 5 seconds limited conversion of the solids.

Jan 1, 1961

By William C. Hood

A leaching column technique that produces effluent similar in quality to coal mine drainage in the Eastern Interior Basin has been developed. The columns are charged with 1000 grams of crushed overburden and cycled through the leaching process once a week for twelve weeks. Inter-relationships among the important chemical constituents are very similar to those present in actual mine drainage waters, but the overall concentrations of ion are more dilute in the leachates. Multiplying the leachate concentrations by a factor of 4.5 gives values similar to mine waters. Available data suggests that each of the leaching cycles represents about three years of natural weathering, so that the leaching technique can predict the evolution of the mire drainage water over a time span of nearly 40 years. Use of the leaching technique with drill core samples should provide a method of approximating mine drainage quality in advance of mining and should be quite useful in identifying potentially toxic units in the overburden. However, the results should he considered to be a 'worst case' situation because the technique' does not consider the effects of reclamation.

Jan 1, 1984

By Douglas Ketcham, Thomas Jetzer

While the neurological and vascular aspects of Hand-Arm Vibration Syndrome (HAVS) has been generally accepted as a medical condition, the medical criteria and the clinical findings used to establish the diagnosis has been more difficult to bring to consensus. The criteria was first quantified by the Taylor-Palmear scale.1 This criteria was subsequently modified in 1986 at the 1st Stockholm Workshop2,3 to included more acceptance for the neurological effects that characterized the predominate findings in some workers. The relationship between hand-arm vibration and Carpal Tunnel Syndrome was defined in NIOSH 97-1414. While the aforementioned documents have defined the clinical entities associated with hand-arm vibration exposure, agreement on the clinical findings and test to confirm the diagnosis has be been more difficult to bring to consensus. Clinicians assessing HAVS has relied on a number of varied neurological and vascular tests. The neurological testing has focused on assessing damage to the sensory capability of the fingers for the neurological component including tests to measuring ability to sense vibration, cold or other end point finger sensor functions. However, the vascular testing has been traditionally focused on the ability to either measure vascular function or to reproduce the vascular blanching that occurs in HAVS with cold water provocation. Recent assessment of this testing in the United Kingdom Coal Miner’s study has questioned the value of this testing especially in reviews by McGeoch.5 In an attempt to provide some type of definitive testing to substantiate vascular damage from hand-arm vibration exposure, angiography is an alternative or adjunct to cold water provocation testing. The standards that have been established to predict the level, type and incidence of HAVS have been based on clinical studies and reports that have essentially been all male populations. However, the recent entry of women into more vibration intensive jobs has brought about the exposure of some women to high levels of vibration previously only previously experienced by men. However, there have been only few studies that look at HAVS in women6. Although exposed the same vibration levels, it has not been clear that the latency and type of pathology of HAVS in women will be the same as for men. The purpose of this study is to look at recent case studies of men and women exposed to jobs with high levels of hand-arm vibration with extensive clinical testing for both the neurological and vascular components of HAVS as well as other associated upper extremity conditions such as Carpal Tunnel Syndrome.

Jan 6, 2006

By Robert J. Dompe

The objective of this program was to develop a cost effective microprocessor-based electronic image sensor system for monitoring pit slope displacement to detect and/ or predict impending slope failure in surface mines. A background study and data analysis yielded a performance specification for candidate Video Slope Monitoring Systems. A design concept was developed based on using a pair of solid state video cameras located on precision pointing assemblies. The digital images from the cameras are compared and, using electronic triangulation, slope topology is calculated. The current and past locations of operator selected features are compared to determine pit slope displacement. A proof-of-concept test was performed using a laboratory model of a pit slope. Based on the successful results of that testing it is recommended that an in-mine evaluation be performed using a full-scale prototype Video Slope Monitoring System.

Jan 1, 1982

By Thomas E. Finch

This report is an engineering-economic evaluation of alternate methods of handling the parting between two coal seams. It consists of evaluations of parting stowing techniques applicable in a representative, thick seam western United States mine. Methods are examined for their potential implementation, and an estimated operating cost per yard of material moved is developed. The methods are of two categories castback or haulback. Haulback methods use truck haulage except With scrapers, and the castback methods are a direct stowage with no intermediate haulage equipment. Possible equipment combinations include draglines, shovels, hydraulic backhoes, bucket wheel excavators, scrapers, and front end loaders. The purpose of this report is to evaluate the effective competetiveness of the various alternatives.

Jan 1, 1975

By K. E. Tame

As part of a Bureau of Mines survey of radioactive waste disposal , a laboratory investigation was made to study such problems in carbonate leaching mills . Because uranium concentrators employing carbonate leaching with caustic precipitation normally recycle barren solutions to the washing circuit , the disposal of liquid radioactive wastes is automatically controlled . However , it was deemed important to determine the actual radium 226 concentrations occurring in this type of milling so that the survey of the entire industry would be complete . The laboratory procedure consisted of leaching the ground ore at 85 ° to 90 ° C and 50 pct solids for 6 hours in a sodium carbonate - sodium bicarbonate solution . The pulp was filtered to obtain a pregnant solution that was reacted with sodium hydroxide to precipitate the uranium as sodium diuranate . Regeneration of the barren solution was accomplished by gassing with carbon dioxide . The solution then was reused by advancing the solution through the washing to the leaching operations . The radioactivity in the pregnant solution was unusually high , averaging 6,500 disintegrations per minute ( dpm ) of radium 226 per liter . However , over 95 pct of the radium was precipitated with the uranium . Consequently , no buildup of radium occurred upon reuse of the barren solutions for washing .

Jan 1, 1964

By W. A. Calhoun

"INTRODUCTION A letter from S. D. Strauss, vice president of Metals Reserve Company, Washington, D.C., dated May 22, 1945, to the chief of the Metallurgical Branch, Bureau of Mines, in Washington; includes the following: Because of the present critical shortage that exists in the supply of corundum required by certain industries in war production, the Reconstruction Finance Corporation, Mr. W. C. Keeley, Vice Chairman for Metals and Minerals, War Production Board, has recommended that the Reconstruction Finance Corporation though Metals Reserve Company, proceed with preliminary mill testing of the corundum ore in Gallatin County, Montana, and that the results of that testing be transmitted to the War Production Board. If the results of the testing work are considered satisfactory, Metals Reserve Company will then provide for the actual mining and milling of the ore for the production of corundum concentrates.Pursuant to the above stated recommendation by the War Production Board, Metals Reserve Company desires to make -use of the facilities of the Bureau of Mines testing plant at Rolla, Missouri, for conducting sink and float and other concentration tests on representative samples of the Montana corundum ore. Two, and possibly three samples of ore are to be tested which will have an aggregate weight of approximately 50 tons."

Dec 1, 1947

By Stephen D. Smith

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rim. Also included are tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1988

By M. A. Schellhardt

The Bureau of Mines has made periodic back-pressure tests on numerous gas wells in the Texas Panhandle field during the past several years to study the delivery capacities of the wells under different pressure and operating conditions and to determine the relationships between pressures and rates of delivery from gas wells.4/ However, information regarding the intake capacities of gas-well systems is meager, end in projects involving the flow of gas into porous-rock reservoirs it has been necessary to determine intake capacities of gas wells by trial. Accordingly the fundamental intake characteristics of natural-gas yells have been studied to develop a method for determining intake capacities under different wellhead pressures from data descriptive of the "output" or producing characteristic of the wells.

Jan 1, 1936

Reduce exposure of longwall face workers to respirable dust generated during the advancement of roof supports. Approach Identify and implement current water-application and improved support-movement practices used to lower support-generated dust. Defining the Problem Bureau studies have shown that on some longwall faces support dust can contribute over 30 percent of the respirable dust exposure of face workers. Conditions contributing to high levels of respirable dust generation during support movement are: depth of cover greater than 1,000 ft; immediate roof consisting of coal top or friable shales; and face-air velocities in excess of 500 fpm. Moreover, at most longwalls, supports are advanced on the intake-air side of the shearer as it travels with the airflow. This places the shearer operators, and in many cases the support movers, downwind of support advance, thus increasing their respirable dust exposures.

Jan 1, 1984

By John P. Harmon

A group of organic chemicals, known as wetting agents, has been developed, primarily for use in the textile industry. These chemicals have the property of reducing the surface tension of water when mixed with it in very dilute solutions. The advantage of lowered surface tension is recognized in dust-control work, and several wetting agents, have been tried by dust-control engineers with varying degrees of success. It is well-known that certain solids, coal for instance, are extremely hard to wet with plain water because of the high surface tension of water and the water-repellent action of coal. If the surface tension of the water is reduced, it can be demonstrated that the coal can be wetted easily. This is accomplished practical and at law cost by dissolving a very small percentage of wetting agent in the water that is to be used for wetting purposes. (Care should be exercised in using a wetting agent to be sure that it will not interfere with a subsequent process.) For some time, the comparative efficiency of various wetting agents has been the subject of considerable work by dust-control men at coal mines, as well as by members of the Bureau of Mines 3/, 4/, 5/, 6/. In this connection, a number of samples of air-borne dust have been collected in the mines. With the exception of dust-control measures conditions of dust generation and dissemination were maintained as, nearly uniform as possible. Samples were collected when water alone was sprayed on the cutter bar of a mining machine; various wetting agents were then successively added to the water and more samples of air-borne dust were-collected.

Jan 1, 1946

By John C. Cook

A 1-year program of exploratory research, to determine the feasibility of radar exploration in advance of coal mining, has been completed. Advance detection of obstructions including faults, clay veins, abandoned wells, and pyritic concretions would improve the safety and efficiency of mining. Initial calculations based on laboratory tests of the RF electrical properties of bituminous coals indicated feasibility; radar waves at frequencies below 100 MHz should be detectable through tens to hundreds of meters of coal and be well-reflected by clay, pyrite and metal obstructions. Using a proprietary, experimental, VHF short-pulse "mining radar" system, two cycles of field testing and equipment improvement were completed. Measurements were made in three bituminous coal mines, a quarry, and a salt mine. Comparisons were made with ground-penetrating radar equipment developed by others for salt dome exploration and for military tunnel detection. The proprietary mining radar equipment and techniques used were found to be the most effective known for coal exploration, but further improvements are needed; one major problem in all systems is interfering clutter signals arising in the equipment and from mine room reverberations through leakage coupling of the antennas to the air. Nevertheless, several practical goals have been achieved: excellent radar reflections were received and identified through up to 30 feet of coal; reflections from a wet, abandoned drill hole were identified by their polarization property and detected at distances up to 272 feet, and mine-wall reflections were detected at distances up to 735 feet (both through salt); propagation through and reflections from large vertical clay veins in coal were demonstrated; experimental results agree reasonably well with theory. The results and experience gained during the project affirm the feasibility of the method. They also provide a firm basis for the development of a practical radar technology for exploration in advance of mining. No Subject Inventions, as defined in the contract, were made in the course of this work.

Jan 1, 1971

By Louis Schaffer

The objectives of the research were to determine whether a model health and safety program could be defined in terms which would enable its application to mines of all types, and, if such a model program could be defined, to determine through evaluations in two mining companies whether it would achieve measurable improvements. Volume 1 describes the model, how it was applied in the field and how it was evaluated. This, Volume 2, describes the literature and field research that preceded the model definition.

Jan 1, 1983

By Howard B. Hamilton

Laboratory performance of mercury filled current limiting devices (CLD) used for high speed switching of DC circuits (600 volts and below, up to 1000 amperes) using a system involving a parallel connected vacuum switch with CLD and an additional series connected vacuum switch was verified in USBM Contract #HO 357079. This report details analytical work and field experimental tests to predict and control voltage surges associated with the high switching speed associated with the switching system. It also details tests conducted to demonstrate the fault current limiting ability of the CLD. Problems associated with designing a fault current limiting system are discussed.

Jan 1, 1978

By Forrest T. Moyer

THIS CHAPTER of the Minerals Yearbook contains injury experience and related employment information for the coal-mining, coking, oil and gas, peat, and native asphalt industries in the United States for 1963. No attempt has been made to combine these data and present injury-frequency rates reflecting the mineral-fuel industries because the hazards of the separate industries are not comparable. Tabulations showing the trend of injuries and employment for all mineral industries are presented in Volume III of the Minerals Yearbook. COAL Injury experience of the coal-mining industry was improved slightly in 1963, as measured by the 2-percent decline in the Injury-frequency rate. Although the total number of fatal and nonfatal injuries increased 1 percent, the greater proportional increase of 3 percent in man-hours worked accounted for the improved frequency rate. Employment and injury data for 1963 are based on final data for anthracite mines and preliminary data for bituminous coal and lignite mines.

Jan 1, 1964

By N. E. Hanna

The current list of permissible explosives includes 124 different brands. Fifteen of these are gelatinous, and the rest are the more commonly used granular ammonium nitrate type. Their rates of detonation range from 1,300 to 5,600 meters per second, and the weights of 1-1/4 x 8-inch cartridges range from 86 to 244 grams. The list of permissible blasting devices includes 1 Cobra, 2 Hydrox, and 9 Cardox models. All of these devices are based on discharge of high-pressure gas from a pressurized shell in a shothole. INTRODUCTION To be approved for use in underground coal mines in the United States, explosives and blasting devices must pass certain schedule tests prescribed by the Bureau of Mines. The explosives listed here were tested under Schedule 1-G,3 which has since been replaced by Schedule 1-H;4 the blasting devices were tested under Schedule 26A.5

Jan 1, 1962

By H. R. Appell

The Bureau of Mines is experimentally converting cellulose, the chief constituent of organic solid waste, to a low-sulfur oil, All types of cellulosic wastes, including urban refuse, agricultural wastes, sewage sludge, wood, lignin, and bovine manure, have been converted to oil by reaction with carbon monoxide and water at temperatures of 350° to 400° C and pressures near 4,000 psig, and in the presence of various catalysts and solvents, Cellulose conversions of 90 percent and better (corresponding to oil yields of 40 to 50 percent) have been obtained. A continuous reactor for use at maximum conditions up to 500° C and 5,000 psig has been operated successfully, Using sucrose as a feedstock, operation in this system has permitted a simplified and preliminary chemical study of the conversion process. Oil yields of over 30 percent have been obtained with this unit.

Jan 1, 1971

By Peter de Bakker

The objective of this contract was to develop a simple, reliable, economical, remote-control roof bolting module for installation of mechanical and resin bolts. It was to be capable of placing longer than seam height bolts, up to 10 ft lengths, from a seam height of 36 to 72 in., while keeping the operator under supported roof. The resulting machine, called REM-Bolter, is a low profile unit that utilizes Foster-Miller Flexible Shaft Roof Drill, a Bendix Roof Bolt Inserter and a newly designed. Roof Bolt Lifter/Torquer. Every effort was made to strike a compromise between complete automation and complete manual control. In a controlled laboratory environment the REM-Bolter remotely installed 1000 bolts. Subsequently the machine was tested in an operating coal mine where 500 holes were drilled (and an equal number of bolts were installed) remotely, over a 4 month period. The results of all tests Live shown that the operator of a machine of this kind can quickly, and repeatedly, install rootbolts remotely from his operator compartment some 8 ft away from the drilling/bolting action. The report includes recommendations for improvements to the present REM-Bolter design that would translate the present test bed into a second generation test bed and a potential first generation production unit.

Jan 1, 1983