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By B. W. Jong

The U.S. Bureau of Mines investigated anhydrous chlorination and caustic-acid leaching processes to recover Ni, Co, Mo, and W from waste hydroprocessing catalysts. In batch laboratory-scale equipment, the chlorination process extracted 61 to 99 pet of the metals. Final recovery was 65 to 99 pct. The caustic-acid leaching process extracted 81 to 98 pct of the metals. Final recovery was 36 to 99 pct. Chlorination processing included roasting, chlorination, hydrolysis of metal chlorides for recovering Mo or W, water leaching of Ni or Co from the spent charge, purification, and solvent extraction or precipitation of Ni or Co from the purified solutions. Caustic-acid leach processing included NaOH leaching, solvent extraction of Mo or W from the NaOH leach liquor, H2S04 leaching of the NaOH leach residue, purification, and solvent extraction or precipitation of Ni or Co from the purified solution. The estimated fixed capital cost for a commercial-scale plant processing 39,000 Ibid of waste Ni-Mo-AI catalyst was $8 million for the chlorination process and $9.6 million for the caustic-acid leaching process. The estimated operating cost was about $0.20 and $0.40 per pound of the waste catalyst, respectively, for the two processes.

Jan 1, 1989

By James P. Ulery, Jon C. Volkwein

The U.S. Bureau of Mines investigated a method of using inert gas to prevent the formation of explosive gas mixtures in auger highwall mining of coal. A combination of gasoline and diesel engine exhaust gases was introduced into the auger drill hole using a short section of pipe located at the collar. Gas samples were taken and analyzed on-site with infrared detectors for oxygen, carbon dioxide, methane, and carbon monoxide. Evacuated bottle samples were also taken and analyzed by gas chromatography in the laboratory. These gas results were analyzed for explosibility. Coal samples from various depths were used to obtain the gas content of the coal using the modified direct method. Personal expo- sure to carbon monoxide was also monitored. The highest methane level observed was 9.55%. The levels of inert gas (carbon dioxide and nitrogen) were sufficiently high to prevent any ignition of the methane. Results showed that for all conditions during mining, gas concentrations were nonexplosive. The gas content of the coal was about 0.30 cm3/g. The maximum personal time-weighted average sample for carbon monoxide was 20 ppm. This system provides a safe, inexpensive, simple method for pre- venting explosions during auger mining.

Jan 1, 1993

By Barbara Fotta

According to the Bureau of Labor Statistics (BLS), workforce estimates of median age suggest that the median age of the mining workforce, which has been experiencing overall declines in numbers of employees, is rising more rapidly than for the overall U.S. civilian labor force. In the absence of detailed demographic data for the mining industry, the current study uses injury and illness data reported to the Mine Safety and Health Administration (MSHA) to examine differences, over time and by commodity, in the proportions of injured or ill workers aged 45 years and older. These data indicate that from 1988 to 1998, the percentage of injured or ill older workers (aged 45 years and older) have been steadily increasing. The most notable increase occurred at coal mining operations where the proportion of injured/ill older workers increased from 24 to 44 percent. A more detailed breakdown of the industry by commodity for 1998 showed the highest proportions of older injured/ill workers (over 40%) occurring in coal, iron ore, alumina mills, cement, and trona operations. In coal operations, as the employment size of the mine operation increased, so did its proportion of older injured/ill workers. Also, higher proportions of older injured/ill workers were observed at surface coal work locations than at underground locations. The distribution of older injured/ill miners by occupation for several select commodities shows the highest proportions for supervisors, electricians, mechanics, and surface equipment operators, and the lowest proportions for surface laborers and for underground coal roof bolters and scoop operators. With few exceptions, older injured workers have the highest median number of days lost per injury when examined by type of mining operation and by occupation. Given the high proportions of older injured or ill workers in many sectors of the mining industry, health and safety programs must consider the physiological changes associated with aging when evaluating job tasks and the working environment.

Jan 1, 2004

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

Data or input files are used to describe the mine's ventilation system and physical characteristics necessary for ventilation calculations as well as the physical or mechanical disturbance to be modeled and simulated Data files are organized into lines of categories or groups of information Each line contains multiple sets of information or data items Data lines are read by the program, and the data items provide information to the program variables The data file is in American Standard Code for Informa¬tion Interchange (ASCII) format, sometimes called a DOS text format Creation or modification of a data file is accomplished with text editor software Most word pro¬cessors are also capable of making the required ASCII type files A sample data file and its associated output are included in appendix B. When selecting software for editing the data files, the user should be aware that the software will also be used for viewing the output of the simulation The output file can be quite large (several megabytes), if a lengthy simulation is performed The output can be sent to a printer for a hardcopy fisting, however, the user should also be aware that most printers currently used with PC's print at rates of 100 to 300 characters per second and large output files may take several hours to print Viewing the output with a text editor can save much time and paper DATA FILE MANAGEMENT The data files describing the event and mine to be simulated can reside either on a floppy disk or in a directory on the hard disk drive When the program starts, the user is prompted for the data file location and name The user response is in the form of a standard DOS path and file name For example, if the data file is on a floppy disk located in drive B and the disk has a directory MYMINE with the data file MYDATA DAT in that directory, then, at the prompt

Jan 1, 1990

By Francis Crowley

Elementary concepts of seismic wave properties are reviewed to establish a framework for discussing seismic noise and its suppression. A liberal number of references is included for those who wish to pursue the topic in detail. A base motion noise level is established for a single surface seismometer. It is argued that simple array processing and seismometer burial should regularly permit us to approach this base noise level which is found in areas free of conspicuous man-made seismic noise sources. The sensitivity of the base seismic level to a number of common disturbances is presented. Solutions that promise to hold the "effective" seismic noise at a site near the base level are given for acoustic, meteorological and fixed local surface sources. Guidelines are suggested for controlling other local man-made sources, e.g. vehicular traffic, by keeping them at sufficiently large distances away from the seismometers to keep noise at permissible levels. These guidelines are speculative and conservative. They should be the subject of future study. The ability to process against general local activity, drilling, and intra- mine sources is limited. Certainly no dramatic gain is to be expected. When strong man-made and/or intramine noise sources are not controllable, detection may well be impossible to achieve, unless the seismometer can be moved close enough to the suspected miner position, i.e. via very deep holes, to compensate for the likely vast differences in strength of the miner signal and the uncontrollable man-made noise sources. However, many intramine sources, e.g., falling water, rock bursts, explosions, etc., may well preclude the existence of a hale miner in their vicinity, and therefore any need to attempt detection of a miner at such locations. The following recommendations are made to enhance the detection and location of a miner signaling seismically. They are: 1. Seismometer burial in slim holes. 2. Narrow band detection, using multiple narrow band filters to cover the likely signal band. 3. Broadband recording and analysis for time-of-arrival estimation.

Jan 1, 1974

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

8. Field Demonstration of the Remote Mine Sealing System in a Coal Mine 8. 1 Selection of Field Test Site Eastern Associated Coal Corporation (EACC) offered its Federal No. 1 coal mine in Grant Town, West Virginia as the site for field testing of the remote sealing system. The choice of Federal No. 1 mine was particularly appropriate as the first attempt at fire control by remote sealing was done in this mine in 1963. EACC provided the men and equipment required for much of the initial preparation. Considerable assistance, advice, and background on coal mining technology was given by Mr. William Laird, Vice President for Research and Development, EACC, and by Mr. Lawrence Jackson, Resident Engineer at the Federal No. 1 mine. District 3 USBM office, the West Virginia Bureau of Mines, the Technical Support Group of the USBM, and Local 4047 of the United Mine Workers of America also cooperated. 8.2 Preparation of Field Test Site 8.2. 1 Underground Site Preparation The underground site chosen for the field testing was in a non-working portion of the mine within a few hundred feet of the main haulage road, as shown in Figure 80. Known as "Seven Switch, " this area was a 20 minute walk or 5 minute "jeep" trip from the man-trip shaft. Ten years having passed since this area was actively worked, considerable effort was required for gob clearing, roof bolting, rock dusting, and rejuvenating the track from the haulage road to the test area. Three primary borehole locations were chosen for the test program. Borehole No. 1 was in a straight passageway

Jan 1, 1973

Part Two of this report is based upon six working memoranda prepared during the first half of 1972 at an early stage in our work for the Bureau of Mines. This work presents preliminary performance estimates of baseband voice and narrowband through-the-earth electromagnetic communications systems of principal interest to the Bureau for operational/ emergency mine communications applications. The calculations were prepared to obtain early indications of the feasibility and governing parameters of such communications systems. They are based on limited, but pertinent, coal mine electromagnetic noise data acquired to-date by Bureau of Mines contractors; on theoretical signal-attenuation characteristics for two transmitter antenna types of present interest to the Bureau and on semi-empirical models which describe the intelligibility of voice communications as a function of the frequency variations of the signal-to-noise ratio across the voiceband. This work examines the cases of baseband voice and narrowband communications for uplink and downlink transmissions, for frequencies up to 3kHz. Downlink transmissions are via a horizontal wire antenna, and uplink transmissions via a vertical-axis loop antenna, for typical mine depths of 300, 600, and 1000 feet. Representative coal-mine overburden conductivities of 10-2 mhos/meter (moderate and common) and 10-1 mhos/ meter (high) were used; the former figure for both voice and narrowband calculations and the latter for narrowband calculations only. Examples of high, moderate, and low, surface and subsurface, harmonic and broadband-impulsive noise conditions were taken from NBS and Westinghouse (WGL) mine noise data, together with examples of high- and low-levels of ELF atmospheric noise taken from M.I.T. Lincoln Laboratory data. The effects of simple voice spectrum shaping techniques on the intelligibility of through-the-earth voice communications are examined, and indexes of intelligibility more broadly based than signal-to-noise ratio are discussed. Finally, a means of overcoming the affects of 60 Hz noise and its harmonics which are the largest contributors to typical audio frequency in-mine noise, is suggested. These feasibility calculations are not intended to serve as definitive and complete treatments, but as a starting point: to establish first-order estimates of the magnitude and variability of transmitter power requirements under different noise, overburden conductivity, and mine depth conditions; to identify relationships, conditions, or frequencies that are likely to limit or enhance system performance; to reveal items requiring further investigation and data still required; and to suggest practical methods for optimizing system performance. These objectives were met by the calculations. Simple experiments to support these calculations can and should be carried out; together with more detailed investigations of specific modulation, coding, noise-suppression, voice-compression and signal-conditioning techniques, aimed at producing through-the-earth operational/emergency mine-communication systems that are not only effective, but practical and economically sound.

Jan 1, 1974

Table XXXIII itemizes the cost associated with the installation of an irrigation system and the application of latex and water in the three experimental areas at Lanse. There were no external labor charges (non- Research Center) except for the installation of the water meter. Cost of pipe and fitting are high because long lines were required at each of the three different locations; these costs were minimized by using plastic instead of metal pipe. Fifteen of the seventeen drums of latex received were used, five drums for each area. [ ] In tank-car lots latex would cost about $0.25/lb so that raw material cost for a 4000 lb/acre application would be in the range of $1,000 per acre. Equipment costs for setting up and irrigation are sensitive to size of area to be irrigated, design of system, and availability and cost of water. A realistic range is estimated to be between $200-500/acre.

Jan 1, 1972

By R. C. Buehl, J. P. Riott, M. B. Royer

Sponge iron is the metallic product resulting from the reduction (removal of combined oxygen) of iron ore or other iron oxides at a temperature below the fusion point of iron. It has been used for many years in the production of certain grades of high-quality steel, such as tool and cutlery steels. The sponge iron available commercially in limited quantities for such use was produced from high-grade ores that were almost free from the contaminating elements that are generally considered detrimental to the production of certain grades of carbon tool steel. Interest in sponge iron as a scrap substitute was revived when World War II began, when the serious shortage of scrap metals for use in the production of armament caused great concern as to whether steel production could be maintained at the rate necessary for vigorous prosecution of the war effort. Also, because of the severe shortage, steel manufacturers…

Jun 1, 1947

By Launa Mallett, Charles Vaught, Jr. Brnich

This paper introduces a technique for incorporating employee participation into the prevention component of a contingency plan. Companies sometimes focus so much energy on response that they forget to put resources into the basics of emergency prevention. The training program discussed here was designed to make employees part of the prevention system. Examples of training materials from the program are provided, a sample method for introducing risk assessment to employees is shown, and a strategy to address limited training time using short videos is explained. Methods for tailoring the training to any worksite and for specific risks are also included. The program is being designed and tested by the Pittsburgh Research Laboratory/NIOSH and employees of an underground coal mine. Examples are taken from the implementation of the program at the mine during the summer and fall of 1998. Results of the program evaluation and lessons learned during the implementation are discussed.

By Kenneth L. Cashdollar

While underground coal technology has progressed over time, regulations on coal dust have not kept up ? the most recent rules are more than 80 years old. The National Institute for Occupational Safety and Health and the Mine Safety and Health Administration conducted a joint survey recently on coal particle ranges as measured in US coal mine samples. In underground coal mines, dust explosions are prevented by the addition of enough rock dust (usually limestone) to make the total dust mixture inert. The rock dust acts as a heat sink for the dispersed dust mixture by reducing the temperature below the value needed to propagate an explosion. Federal regulations require 65% in combustible content in intake airways and 80% incombustible content in return airways, where the coal dust is assumed to be finer in size. The regulations also require an additional 1% incombustible for each 0.1% methane in the ventilating air in intakes and 0.4% additional incombustible for each 0.1% methane in returns.

Jan 1, 2008

By R. V. Ramani, P. M. T. White, D. Sutton

4.1 Introduction Using methods outlined in previous sections of this report, programs were written and/or obtained to: i) select best combinations of "a" and "k" for up to 8 different value parameters, ii) calculate available and unavailable ore tonnages and other statistics, and iii) produce contour maps of various parameter characteristics and available tonnages on a line printer. All the above programs are written in Fortran IV for execu¬tion on IBM 360/370 computers. 4.2 Calculation of Coal Reserves The Ore Reserve program suite consists of the following sections: (a) UNIT 1: This unit is a subroutine called by Unit 2 to determine values for "a" and "k" from the given data. (b) UNIT 2: These programs calculate ore reserves and are composed of a main program and several sub¬routines. In the following, their functions are abbreviated: i) MAIN - calls subroutines, reads run parameter variables, reads borehole data and interpolates grid node values for the area of investigation

Jan 1, 1974

By John C. Machisak

THIS CHAPTER of the Minerals Yearbook (Volume III) contains overall employment and injury experience for coal mines-bituminous, lignite, and anthracite; coke, petroleum and natural gas; and peat and slag plants; metal and nonmetal mines; sand and gravel operations; stone quarries; metallurgical plants, including metal mills and smelters; and nonmetal mills for 1959. Volume I of the yearbook contains injury experience and employment data in the metal, non-metal, sand and gravel, slag, and quarrying industries, and the milling operations and related plants. Volume II contains the injury experience and employment data in the fuel industries--coal, coke, petroleum and natural gas, and peat. Surveys conducted by the Bureau of Mines were the source of injury and employment data used to compile the tables and furnish information for the accompanying text. Response to the surveys was voluntary except that for coal mines. The Coal Mine Safety Act requires operators of coal mines to furnish the information requested.

Jan 1, 1960

By Oliver C. Ralston

OUTSTANDING TRENDS of the year included the following: 1. Concentration and beneficiation of iron ores to provide improved blast-furnace feed and extend ore reserves. 2. Successful development of pelletizing and sintering procedures for fine iron ores. 3. The realization that cyclone separation could replace existing classifiers in many grinding circuits. 4. The rapidly blossoming metallurgy of ultrapure silicon and improvements in zone melting. 5. The rapid increase in the use of liquid-liquid extraction and ion exchange in hydrometallurgy. 6. The industrial application of vacuum melting on the 100-ton scale. 7. The hope for developing a columbium (noibium) base alloy for high-temperature use. The technologic advancement in metallurgy that had the greatest effect on the American economy was the beneficiation of iron ores to give improved feed for blast furnaces and indirectly extend our ore reserves. This was not a sudden development but rather culmination of a decade of intensive effort.

Jan 1, 1958

By Kevin Connor

Exports of agricultural products, mostly coffee, continued to account for more than 90% of Burundi's foreign exchange revenue. The country's ban on commercial mining was lifted in 1987. Mining of peat for fuel, limestone for agriculture, and clay for insecticides continued as in previous years. At yearend, Burundi's external debt stood at almost $700 million.2 Amoco Burundi, a subsidiary of the Amoco Petroleum Co., drilled two exploration wells in northern Lake Tanganyika in 1987. No oil was found, but preliminary findings were encouraging enough that further seismic surveys and offshore and onshore drilling exploration were planned in 1988. Any oil or gas finds would have substantial impact on the Burundian economy because a major portion of the country's trade deficit was directly attributable to petroleum and gas imports. The Zaire Government agreed in June to let Amoco Burundi explore Zaire's side of Tanganyika using the same equipment and personnel being used in Burundi.

Jan 1, 1989

By Ronald S. Conti

Fire is a major concern for those who work in underground mines. A mine fire can occur at anytime and often results in a partial or total evacuation of mine personnel and could result in the loss of lives. Therefore, having a workforce that is well trained to prevent, detect, and fight a fire is important. This paper focuses on responders’ preparedness for fire. Responders in this context are considered the entire workforce and are categorized as first, second, and sustained responders and evacuating miners. Quality training enhances ones awareness of mine fire hazards and promotes self-confidence in combating fires and responding to emergencies. Early warning systems and other escapeway aids such as a through-the-earth signaling and communication system, lasers and strobe lights are also addressed. The technological advancements that have been made can improve the state-of-preparedness for responders to underground emergencies and increase the chances of survival for escaping personnel.

By J. S. Tosh

An equilibrium study of the system potassium carbonate, potassium bicarbonate, carbon dioxide, and water has been conducted with solutions of 20-, 30-, and 40-percent equivalent potassium carboaate concentrations. These equilibrium data cover the operating range of the hot carbonate scrubbing system for removing carbon dioxide from gas mixtures. Such data are necessary to establish the limits of purification and are used to design absorption and regeneration towers. Values of K in the relationship K = (KHCO3)2/(K2CO3)PCO2 were determined for higher temperatures of 70" to 140° C. and greater concentrations, I 20 to 40 percent, than employed by previous investigators. For the 20- and 30-percent concentrations, K is constant at a given temperature; thus, once K has been determined the equilibrium pressure of carbon dioxide can be calculated for any conversion. Variation of & values with changing conversion was observed with the 40-percent solutions, so that equilibrium calculated pressures are less reliable from average K values.

Jan 1, 1959

By W. C. Phalen

"The term ""manjak"" is applied to a variety of bitumen or solid hydrocarbon occuring on the Island of Barbados, West Indies, and in Utah, Cuba, and Trinidad. The deposits on the latter island are found within a distance of three miles of San Fernando, the second largest town on the Island, and within three miles of the famous asphalt lake.In chemical composition, manjak is like asphalt. It is almost pure bitumen. Its melting point is, however, more than 4000F. whereas asphalt melts at 1000F. In composition, it consists of 80 to 90 per cent carbon, the balance being chief¬ly hydrogen, with a small quantity of sulfur. It resembles coal in appearance, is odorless, hard, and brittle. It is found in thin beds between layers of clay.The island of Trinidad is rich in this mineral resource. Its development has as yet hardly begun, and the exportations already made have been with the view of testing out the ma-terial. During 1918, exports to the United States were valued at about $3100, and in 1919, up to October 1, they totaled 41 tons, valued at $1900. Prior to 1900, manjak was mined on a small scale in Trinidad, but for various reasons, very little was done between 1900 and 1913. In the latter year, mining operations were resumed by the Trinidad-Tarouba Oil Development Company, of San Fernando. At the present time, there are five shafts, one of which has reached a 37 foot bed of manjak at a depth of 400 feet. Operations could be greatly extended if there were a greater demand for the material.It has not been found profitable to export manjak from Trinidad in the crude state as the price received, namely $35 per ton, hardly covers mining expenses. These are increased by the necessity for careful and thoro timbering on account of the clay formation.Compounds, made by combining manjak with mineral oil command fair local prices which have enabled mine operations to proceed at a profit. Experimentation is still in progress with different mixtures of manjak and oil for various purposes. The manjak, recently sent to the United States was for the purpose of ascertaining whether American oils would be more economical and useful for mixing with the manjak than the Trini¬dad oils. It is the plan to erect a plant very soon for the manufacture of a variety of manjak paints and compounds.Manjak is rapidly increasing in use, particularly in connection with the oil industry. It is produced in close proximity to the oil wells in Trinidad. It is boiled with oils at high temperatures and converted into compounds and paints for nearly every purpose where a preservative is needed, for example, on pipe lines, boilers, chimneys, and miscellaneous iron ware, machinery, etc. It is usually applied in the liquid state, hardening into a tough, rubberlike coating. It has low viscosity, and is not affected by ordinary heat. It makes an excellent insulating material and is impervious to both air and water. In hot and damp climates, like that of Trinidad where pipe lines quickly deteriorate, their life has been pro-longed for extended periods when painted with this material."

Nov 1, 1919

By J. S. Peterson, G. P. Cole

The National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Center (PRC), has conducted research to improve electrical fault detection on coal mine direct current (dc) trolley systems. Present circuit breaker protection systems are current-magnitude-based and cannot discern between normal traffic and high resistance electrical faults. Tests were conducted at cooperating mines to assist in developing a neural-network-based detection algorithm for distinguishing between electrical faults and normal operation. The Fast Fourier Transform of the trolley rectifier current signature served as baseline data for the neural network. During field tests, the algorithm performed with greater than 90% accuracy.

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

B 5 Typical Input - Ouput The input data and the printed output for case 8 of the simulations (Section A.4) are shown in the following. The branch, level, node, miner and hoist numbers mentioned in the input and output refer to the corresponding numbers in Figures A-3, A-4 and A -5, The plotted ouput, already shown in Figures A,11 and A-12 is not repeated. The input data shown does not include the following simulation parameters: DTIME = 0, 05 FTIME = 130 JPLT(K) = 1 for K = 1, 2, 3 0 for other K TPLSTR = 0.0 TPLST P = 130

Jan 1, 1976