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By V. F. Parry

The major industrial uses of char or semicoke produced by low-temperature carbonization of coal4/ are as fuel for generating electric power, for blending with metallurgical coking coal as a substitute for low-volatile coals, and for gasification to produce synthesis gas for chemical purposes. This paper discusses various methods for carbonizing coal, emphasizing processing of the noncoking coals to produce char for thermal power-plant fuel and for blending with metallurgical coking coals and tar for chemical use. Low-temperature carbonization is a relatively simple processing step involving heating coal to about 900° to 1,200° F. to decompose the coal into 4 main products: (1) Semicoke or char; (2) complex, partly oxygenated liquid hydrocarbons or tar; (3) fixed gases; and (4) water. If the coal is heated rapidly under conditions that prevent decomposition of the primary products, 68 to 87 percent of the net heat in the raw coal is left in the char and 10 to 23 percent of the potential heat appears in the primary tar. Fixed gases represent approximately 7 percent of the heat and approximately 2 percent is lost or dissipated in the reactions of decomposition. Considering the different ranks of coal in the United States, the yield of tar will vary from about 9 to 44 gallons per ton, therefore it is important that each coal be carefully considered if it is to be carbonized for industrial use.

Jan 1, 1955

By J. R. Thoenen

This paper outlines briefly results of seismic measurements recorded in the vicinity of quarry blasting under practical operating conditions. The data cover field work done from January to the middle of August 1930, during which time records were made of 61 blasts in 19 quarries. Of the tests made, one was in biotite-gneiss, two in dolomite, two in a flintlike volcanic complex, three in gabbrodiorite, five in trap rock, and six in limestone. One quarry was in Alabama, two were in South Carolina, two in New York, four in Kentucky, five in Connecticut, and five in Massachusetts. Explosive charges ranged from 0.30 pound to 41,900 pounds, and the method of shooting varied from mud caps through hammer and wagon drill holes to churn drill holes and coyote tunnel shots.

Jan 1, 1937

By P. R. Tisot

Knowledge acquired from this research contributes to a better understanding of the physical structure of Green River oil shale and provides fundamental data and concepts that may serve to improve oil-shale technology. This study by the Bureau of Mines indicates that oil shale is a highly consolidated organic-inorganic system with no significant micropore structure, pore volume, or internal surface. This system is a form of physical structure that precludes rapid diffusion of either gases or liquids. The mineral matter consists essentially of nonspherical particles that tend to follow a log-normal size distribution. An excess of 99 weight-percent of these particles have equivalent spherical diameters of less than 44 microns--75 weight-percent are from 2 to 20 microns, and 15 weight-percent are less than 2 microns. The surface area (3 to 5 square meters per gram) of these mineral constituents is mainly external surface. The mineral constituents contain some micropore structure--pore radii ranging from 10 to 100 Angstrom--with the pore sizes randomly distributed. Distribution of the organic matter within the inorganic matrix is essentially interparticle and not intraparticle. The organic matter within the micropores of the mineral constituents is less than 4 percent of the total. Estimates made from surface area data suggest that perhaps only a small amount of the organic matter is bonded either physically or chemically to the mineral constituents.

Jan 1, 1963

By Robert C. Gabler

Evaluation of incinerated sewage sludge as a secondary resource for aluminum, phosphorus, and minor constituents such as copper and zinc was initiated as part of the Bureau of Mines secondary resource program. The elemental composition of sludge ash for 14 plants in 11 U.S. cities was determined. Comparing industrialized cities with cities where most of the sewage is domestic, significant differences in heavy metal content were noted. Various parameters were investigated affecting the extraction of metals and phosphorus from a typical industrial city sludge ash and from a Palo Alto, Calif., sludge ash with a high precious metal content. Three extraction-recovery procedures for metals and phosphorus using sulfuric acid leaching, ion exchange, and various precipitation techniques were investigated. The last procedure developed was a combination approach using a three-stage countercurrent sulfuric acid leach that recovered most of the economic values from the sludge ash and also removed the leachable fraction of elements of environmental concern.

Jan 1, 1979

By H. M. Smith

The production of oil during the early development of new oil fields is usually accompanied by large quantities of natural gas. Since in most fields gas under pressure is the main source of the energy causing the oil to move through the sands into the wells and thence to the surface, coincident production of natural gas will continue as long as present-day producing methods are used. Generally the use of this gas is restricted, since markets are not readily available. Consequently, a large portion of the gas produced is often wasted by being blown into the air. The magnitude of gas waste is well brought out in the following statement by Miller:5 Only a few outstanding examples need be cited to show the enormous production of gas that accompanies the discovery of new sources. In April, 1927, the Ventura field produced approximately 210,000,000 cubic feet of gas a day; and during the summer of 1927 Alamitos Heights reached a peak gas production of 102,000,000 cubic feet a day; on December 1, 1928, as a result of the summer's deeper drilling in the Long Beach field, surplus gas production amounted to 125,000,000 cubic feet a day. It is estimated that in January, 1929, the Santa Fe Springs field will have a daily gas production of 387,000,000 cubic feet from the recently discovered Buckbee oil zone. Of this amount 274,000,000 cubic feet a day will be the surplus above the amount required for field and plant fuel, taken out by utility corporations, and that used in repressuring the Meyer sand which lies above the Buckbee zone.

Jan 1, 1931

By Forrest T. Moyer

THE injury data and experience in this bulletin are presented in three general sections. The first section contains general and detailed data relating to 1948 injury experience in bituminous-coal and Pennsylvania anthracite mines, separately and combined into totals for all coal mines. The related employment, worktime, production, and productivity data are given in each breakdown of the statistical data. Tables 1 through 22 constitute a subsection and present statistics on number of injuries, frequency and severity rates, average severity, detailed and major causes of injuries, injury records of the coal-producing States, distribution of injuries by part of body, and distribution of injuries by days of disability. Tables 23 through 45, the second subsection, present injury experience in bituminous-coal mines by various selected factors of physical or operating conditions that ma contribute to the occurrence of injuries. The degree of mechanical loading, productivity, size of mine by number of men working and by tonnage mined, thickness of bed, length of shift, number of shifts, type of cap lamps, rating of mine as gassy or nongassy, type of ventilation, and combinations of these factors influencing mine safety are presented in this group of tables. Similar data on Pennsylvania anthracite mines are listed in tables 46 through 63, which comprise the third subsection. The second section of the report contains the generalized annual injury records of bituminous-coal, Pennsylvania anthracite, and all coal mines from the earliest available data through 1948. Tables 64 through 97 list the number of fatal and nonfatal injuries, injury rates, and causes of injuries on an industry basis, the long-term injury records of each coal-producing State, and the related employment, worktime, and production data.

Jan 1, 1952

By W. J. Kroll

This report on the bibliography of zirconium has been confined to those publications and patents that appear to be useful in the commercial development of the metal, both the malleable and the nonmalleable. The methods of production have been stressed and special attention has been given to the alloys. Compounds of importance, like the oxide and chloride, for the manufacture of the metal or of the alloys have been considered. The use of the oxide in refractories anal in the glass and porcelain industries has been omitted. The present survey is critical; that is to say, an attempt has been made to evaluate the effectiveness of suggestions made in the literature. The exhaustive work of Marden and Richy, Bureau of Mines Bulletin 186, published in 1921, has been taken as a base to start from with the intention of bringing the subject up to date with material published in the last 24 years. During this time there was considerable 'advance in the preparation of the metal and Its alloys, and in the development of new uses. On the other hand, there was little progress in the methods of decomposing the ores, so that the chapter on this latter phase is necessarily short.

Jan 1, 1946

By Richard D. Miller

This Bureau of Mines publication contains analyses and related source data for 224 natural as samples from 18 States. Of the total, 191 sam¬ples were collected during calendar year 1981. The remaining 33 samples were collected during previous years, but releases, granting permission to publish were not received until 1981. All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by the mass spectrometer and special helium apparatus described previously (1-2).3 The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the general public. Twenty-five publications have presented the results of 12,827 gas analyses made prior to 1981. The first three bulletins (1-3) contain analyses and related data on 5,218 gas samples collected from 1917 through 1960; these bulletins have been supplemented annually by information circulars (4-17, 19-24) containing 7,609 analyses of samples collected since 1960.

Jan 1, 1982

By D. J. Dollhopf

A week-long selective overburden handling dragline op ration was conducted at a strip mine near Colstrip, Montana. The objective of the demonstration was to hvdrologically isolate a saline overburden zone during placement in the spoil piles. The saline zone had concentrations considered inimical to successful reclamation and was potentially dangerous to future water quality in the spoils aquifer. The zone was identified after review of chemical data for overburden samples collected from the intense 60 m grid drilling pattern. The saline zone in the overburden was: 1) handled in a normal manner; 2) segregated and buried; and 3) segregated, buried, and covered with a relatively impermeable 1.0 m thick clay cap. The method used to formulate this demonstration, the demonstration itself, and the monitoring and evaluation techniques are described in this report. Observation wells were installed to monitor ground water in the overburden, Rosebud coal, and McKay coal. Data from these wells were, used to estimate post reclamation water levels and to evaluate recharge and water movement characteristics in the vicinity of the demonstrations. The inimical zone was successfully handled in a selective manner with a minimum of delays. Economic analysis indicated cost of these selective burial operations to be about 1.1 to 1.5 times the cost of the normal operation at this particular mine site. Long term monitoring will be required to evaluate the effectiveness of these handling techniques in hydrologically isolating undesirable overburden materials.

Jan 1, 1977

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations 4251. The factual data obtained during the project are reported in a series of Reports of Investigations beginning with No. 4251, of which this is the fifteenth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by halt townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification and its location and name are shown on the appropriate half-township map. The description of each half township is followed by a description of each deposit developed in that half township. The 14 halt-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on figure 13 in volume 1. The Descriptions of the deposits developed are followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each halt township is given with the discussion covering that area.

Jan 1, 1948

By Allen D. Look

Underground fires often prove difficult to control , and a small fire can quickly grow into a large one , endangering life and causing large property damage . Even a small underground fire may produce enough noxious gases to cause suffocation ; therefore , every precaution should be taken to prevent and control such fires . It is ironic that mine fires should be caused when utilizing materials that are in themselves fire - resistant ; yet , cutting and welding of iron and steel are proving to be common causes of underground fires in metal mines . This paper includes 19 examples of underground fires of this nature , and undoubtedly this is only a fraction of the number of similar fires that have occurred in the last few years . This paper will review some metal - mine fires caused by cutting or welding and point out precautions to be taken to prevent other fires from this cause .

Apr 1, 1948

By Frederick W. Horton

With large deposits of low-grade molybdenum ore and a latent market for molybdenum, which with development might perhaps equal that for tungsten, the United States has for years made no pro- duction of molybdenum ore worthy of mention. In fact, during the decade previous to 1914, there was no output of molybdenum ore in this country except in 1905, 1906, and 1907, when a few small lots of molybdenite and wulfenite were marketed." To ascertain why this possible source of economic wealth should remain undeveloped, the United States Bureau of Mines undertook an investigation in 1914, with a view of assisting the establishment of a molybdenum industry in this country. A preliminary review of the situation showed the following conditions: Briefly there was a lack of any considerable demand for molyb- denum for the one known use that might consume any large tonnage of it, that is, for the manufacture to certain alloy steels to which molybdenum imparts properties roughly similar to those produced by tungsten. It was at once evident that the market for molybdenum in alloy steels must be developed, or that extensive new uses for the metal must be created, before the demand would be sufficient to war- rant any extensive mining of molybdenum ore. Investigation showed that one of the chief factors in retarding the development of any demand for molybdenum by the alloy-steel trade was that manufacturers who might use, or might investigate the possibilities of using, the metal were kept out of the market by the fear of not being able to obtain steady supplies. On the other hand, those who might be interested in the development of some of the extensive low-grade molybdenite or wulfenite deposits in this country were prevented from doing so by the small visible demand and the fear that any large production would glut the market. Owing to these conditions the mining of molybdenum has in the past been confined almost entirely to small-scale operations on high-grade streaks of molybdenite ore, and the methods of recovery have been limited largely to cobbing and hand picking.

Jan 1, 1916

By Richard D. Smith

The Bureau of Mines evaluated the emission control methods, including the capital investments and operating cost, necessary for further reducing lead levels in ambient air at the Glover, Herculaneum, and Buick smelter-refineries in Missouri and the East Helena, MT, smelter. The U.S. Environmental Protection Agency (EPA) has proposed more stringent lead in ambient air standards than those currently in effect. This report presents theoretically achievable lead emission reductions and estimated capital and operating costs. Lead emission inventories theoretically can be reduced from 1985 levels by 2,421 lb/d at the three Missouri operations by containing and filtering fugitive emissions within structural enclosures and baghouses. The aggregated capital and operating costs in 1986 dollars using conventional environmental and workplace technologies are estimated to be $250,014,100 and $18,507,800, respectively. Estimated total incremental cost is $0.063/lb as refined lead. Additional regulatory costs attributable to Occupational Safety and Health Administration (OSKA), U.S. Department of Labor, workplace standards are included since proposed environmental controls may otherwise degrade workplace conditions. Continuous drossing is evaluated as an alternative to conventional OSHA controls. Substituting continuous drossing for conventional work- place technology results in an estimated aggregated capital and operating costs of $258,344,800 and $15,719,600, respectively. Estimated total incremental cost is $0.062/1b as refined lead. For comparison, the average open market price of refined lead during the first quarter of 1986 was $0.184/lb.

Jan 1, 1987

By Forrest T. Moyer

The safety record of the mineral and mineral-fuel mining and processing industries in 1966 was improved slightly for the second consecutive year as indicated by reduced injury-frequency and injury-severity rates. The overall operating activity was higher in 1966, as measured by the increased number of men working and the total man-hours of worktime. Injury Experience.-The rate of occurrence of all disabling work injuries in the mineral industries was 17.38 per million man-hours in 1966. This overall rate comprised frequencies of 0.28 for fatal and 17.10 for nonfatal work injuries, compared with respective rates of 0.28 and 17.26 in 1965. Fatalities totaled 543; 5 more than in 1965. The total of 33.091 nonfatal injuries was 291 higher than in 1965. However, the larger number of disabilities was offset by the increased worktime in 1966. so that the fatality frequency was unchanged and the nonfatal frequency rate decreased from 1965.

Jan 1, 1967

By W. C. Holliman

This report on the characteristics of commercial aviation gasolines is one of a series of such reports. It presents compilations of' inspection data furnished on their products by 15 manufacturers of commercial grades of aviation gasoline and special data obtained in Bureau of Mines laboratories on 68 samples of these gasolines. Data are presented for 18 samples of grade 80, 20 of grade 91/98, 21 of grade100/130, and 9 of grade 115/145 aviation fuels. The gasolines are designated January 1948 production, although some of the samples actually were produced at a later date.

Jan 1, 1948

By C. P. Bowie

For years many oil producers have believed that often low-pressure oil- and gas-bearing strata have been over coked in fields where the rotary system of drilling has been used. Collom3/ gave as a reason for this con¬dition that because the mud fluid was thick, the oil or gas stratum was plastered and sealed as the tools passed through it and no oil showed at the surface. Although this observation was made 15 years ago, it may often still be true notwithstanding modern developments in coring and electrical logging. Operators have believed, also, that mud fluid does not solidify behind the casing. Lewis and McMurray4/ stated: "All the evidence obtainable from practical experience points to the fact that the mud fluid properly mixed and employed does not solidify behind the casing, even in deer wells and after long periods."

Jan 1, 1937

This report describes the new Bureau of Mines Core Repository System (CORES) and presents the methods for selecting, processing, and storing physical samples and descriptive data for future reference by earth scientists. The system preserves splits of chip samples and longitudinally sliced segments of core. A records retrieval system provides for storage of data on microfilm and magnetic tapes and uses the keysort parameters of location and commodity for the identification of data.

Jan 1, 1978

By Carl R. Christiansen

The primary objectives of this project are (1) the determination of manpower demand in primary lead and zinc production for the years 1985 and 2000, and (2) the estimation of the availability of the required manpower for these years. In order to meet the first of these objectives relationships between employee requirements and metal production in the various states were established, The total primary lead and zinc production from United states mines in 1985 and 2000 has been predicted by the U.S. Bureau of Mines. These forecasts and the 1974 figures are as follows: [1974 1985 2000 Lead metal, tons 669,000 700,000 900,000 Zinc metal, tons 494,000 585,000 995,000] Mining By analysis of ore reserve data and industry characteristics, the authors estimated the portion of the primary production which each state would yield in the future years. As manpower requirements are determined by the tons of ore produced and by worker productivity, these figures were determined for each mining state and district by developing relationships between lead and zinc metal production, ore production, ore to recoverable metal ratios, employee productivity, and number of employees required. The number of new employees required annually to compensate for attrition and production growth is provided, also.

Jan 1, 1975

By John S. Berber

Acids, neutral oils, and pitch were produced by distillation of low-temperature lignite tar and processed to upgrade them into more valuable products: The acids were separated from the distillate and catalytically dealkylated to produce phenol, cresol, and xylenol. Aromatic and naphthene fractions of the neutral oil were converted into phthalic and maleic anhydrides by catalytic hydrodealkylation and vapor- phase oxidation. Paraffins and n-olefins from the neutral oil were processed into alkybenzene sulfonate, a biodegradable substance. Aromatic materials from the neutral oil were also extracted with organic compounds and the extract hydrogenated under pressure to produce jet fuel. The pitch was processed by various means to change its characteristics and make it suitable for similar applications as high- temperature tar pitch, including preparation of carbon black and metallurgical electrodes. In most cases, products obtained from the low-temperature tar were examined for physical and chemical characteristics and for potential commercial utility. Information obtained from this research would be helpful if a new coal- chemical industry based on tar utilization were established.

Jan 1, 1973

By W. W. Agey

Past investigations on waterborne impurities in the flotation process have been concerned primarily with the treatment of specific ores with particular local waters. Although some anions and cations present in water are known to react with flotation reagents, a definitive study has not been made on the effect of such common ions upon the flotation process. This report describes the fundamental research undertaken to define and measure the adverse and/or beneficial effects of different concentrations and combinations of several common anions and cations when oleic acid is used to froth-float limestone from a pulp of quartz and limestone. Research on the effect of waterborne impurities upon the flotation process was composed of two equally important phases. The first phase comprised development of a procedure for floating limestone from quartz that would give the same results in test after test. Some difficulty was encountered, but once such a procedure was developed, the second phase, comprising study and measurement of the effect of various ions c on to natural water upon the flotation of limestone, was quickly completed.

Jan 1, 1963