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By R. F. Stewart

A sedimentation method involving the use of the Palo-Travis apparatus was found satisfactory for rapid determination of the size distribution of coal particles ranging from 10 microns in diameter to those passing an 840-micron opening (20-mesh sieve), The method is most useful for comparing the size distributions of samples of pulverized coal where the actual size of the particles is not required and is applicable to sieve and subsieve sizes of a wide variety of coals and chars that can be wetted and are heavier than water. An analysis, including all calculations, can be completed in 1/2 to 10 hours, depending on the time required for the finely divided coal to settle. A typical analysis requires about an hour, making this a rapid, precise method for routine size-distribution analysis of powdered coals. When used with coal particles smaller than 400 microns, the method is precise within 15 microns for wide variations in test conditions and within 5 microns for identical test conditions. The precision decreases as particle size increases, becoming unsatisfactory for particles larger than 400 microns (40-mesh). For precision within 15 microns, the samples must be equal in weight. Greater precision is obtained with 4-gram samples, but samples as small as l gram may be used.

Jan 1, 1961

By V. E. Homme, M. M. Wong

Tests were made in reactors ranging from 12 to 30 inches in diameter to develop methods for the preparation of sodium chloride - titanium lower chlorides ( dichloride and trichloride ) melts that contain titanium predominantly in the divalent state . Such melts are desirable as a starting material for the production of titanium metal or as an electrolyte for electrorefining of titanium . Sodium reduction of TiCl with an 18 - hour period of holding the reaction products in the molten state produced melts that contained titanium lower chlorides in TiCl₂ - to - TiCl , molar ratio of approximately 8 to 1. Sodium reduction of TiCl in a reactor with a shielded pipe weir , that required no melt -holding period , produced melts with a TiCl₂ - toTiCl , molar ratio as low as 4 to 1 . Reduction of TiCl4 with scrap titanium metal in molten sodium chloride produced relatively pure melts containing about 27 percent titanium in a Ticl₂ - to - Ticl , molar ratio of approximately 4 to 1 .

Jan 1, 1964

By R. B. Moore

The story of helium is one of the romances of science . Probably nothing , except perhaps radium , compares with it in human interest . Helium is one of the best examples of a discovery in pure science that has wide commercial application . In 1868 , an eclipse of the sun was visible in India , several scientific men who were in India making observations of the eclipse turned a spectroscope for the first time on the solar chromosphere - that part of the atmosphere of the sun , about 10,000 miles deep , which merges into the corona . A bright yellow line was observed and was thought at first to be due to sodium . Janssen showed , however , that this line was not just the same as either the D or D₂ line of sodium, although it was extremely close to these lines , hence he suggested that the new line have the designation D₂ . Frankland and Lockyer decided that Dz was due to an element in the sun not previously discovered on the earth , and suggested for it the name "Helium" from the Greek work " Helios " the sun . For several years nothing more was done in connection with this element . In 1894 , Sir William Ransay , in conjunction with Lord Rayleigh , made his memorable discovery of argon in the atmosphere , which was announced at the British Association meeting in the same year . After this discovery , Ramsay looked for other sources of the element . Through Sir Henry Miers , he learned that Dr. W. F. Hillebrand , of the United States Geological Survey , had obtained an inert gas from certain uranium minerals , which gas he had decided was nitrogen . Ramsay believed that part of it might be argon ; he obtained from Hillebrand for experimentation , a sample of the mineral , cleveite , one of the uranium minerals , and after extracting gas from the mineral and purifying it , he ran it into a spectrum tube . The lines obtained ' were , however , different from those of argon; among them was the bright yellow line noted by Janssen . Thus was terrestrial heliun discovered .

Jun 1, 1922

By J. C. LaScola

Development of methanometers and anemometers for underground use in coal mines is reviewed. The first semicontinuous recording methanometer was developed in 1961 in West Germany. The Bureau of Mines developed an instrument using; pellesters that was a continuous recording methanometer. Expansion of freon gas created a vacuum which pulled the methane-air mixture through a tube to an electrically heated, catalyst-impregnated pellester where the mixture was burned. The National Coal Board of England developed a continuous recording methanometer based on the principle of the Davy flame safety lamp. A thermo-pile was used to sense the hurt output of the flame. Finally the Bureau of Mines improved its methanometer by eliminating the freon gas and using a diffuser head to a monitor methane-air mixtures. Development of recording anemometers proceeded from the use of a photo¬cell and light source to sense rotation of the Biram-type anemometer blades to the use of a Hall detector to sense, rotation by measurement of electromagnetic pulses.

Jan 1, 1969

By John W. Cole

The Butte district has been the principal producer of metallurgical-grade manganese in the United States since World War I. Manganese dioxide nodules are produced from rhodochrosite ore by concentrating the rhodochrosite and roasting the concentrate in rotary "cement-type" kilns. The Anaconda Copper Mining Co. is the only producer at present. Under the stimulus of a purchasing program administered by Metals Reserve Company during World War II, however, several independently owned or operated mines (including the Norwich) produced manganese carbonate ore. These mines were examined in Juno 1949 by John W. Taber, mining engineer, Bureau of Mines. A core-drilling program to develop ore in the Norwich mine was recommended and approved. drilling was completed early in 1950. This report gives factual data obtained.

Jan 1, 1951

By R. D. Leitch, C. A. Taylor

Trinitrotoluene is made by the direct nitration of toluene by a mixture of nitric and sulphuric acids . The exact procedure varies , but the product , where Grade I of TNT is desired , is similar , and consists largely of material that has a melting and setting point of 80.6 °c . The purification consists of draining off the liquid portions , including the acid and liquid nitro compounds . The mass is crushed and washed until the TNT is acid - free . It may still have a low-melting point due to the presence of material of lower nitration. Other isomers also have the same effect . The crystal mass may be washed with a solution of sodium sulphite , thiosulphate , sulphuric acid , or with an organic solvent such as alcohol , benzene , or carbon tetrachloride , Where a very pure product is desired , the TNT is separated by fractional crystallization from solution in organic solvents . The TNT is If it forms In some cases the material is melted during purification . agitated as it cools to prevent solidification in a solid mass . in a solid mass , this is broken up and screened . There has been some question as to the effect of the different methods of purification on the strength and sensitiveness of TNT , although all methods left a product that would give satisfactory tests .

Sep 1, 1923

By G. C. Branner

The bauxite diagram presented as figure 1 was developed to clarify, by graphic means, the theoretical chemical constituents of gibbsite-kaolinite-type bauxite for all possible proportions of these two minerals from pure gibbsite to pure kaolinite. The tables in the report reflect the same date. The diagram provides (1) a graphic representation of the relations of constituents with respect to a ill possible percentages of alumina and silica, (2) a basis for verifying the accuracy of analyses of gibbsite-kaolinite bauxite, and (3) a basis for estimating the type and proportion of alumina hydrate and/or silicate minerals that may be present in gibbsite-kaolinite-type bauxite. The diagram, with accompanying interpretations and use formulas, will be useful to those connected with the mining and processing of bauxite.

Jan 1, 1955

By J. H. Field

Results of studies by the Federal Bureau of Mines on a pilot-plant scale for removing hydrogen sulfide and carbonyl sulfide from gas mixtures by the hot carbonate system are given in this publication. Gases containing up to 10 pet. hydrogen sulfide and 48 grains carbonyl sulfide per 100 cu.ft. were treated. In most tests carbon dioxide also was present and was removed simultaneously with the sulfur compounds. Because the rate of absorption of hydrogen sulfide is much more rapid than that of carbon dioxide over a wide temperature range, selective removal of hydrogen sulfide occurred in the bottom section of the absorber near the point of gas entry. Hydrogen sulfide was removed to pipeline specifications with carbonate solutions by using split-stream flows in the absorber and regenerator.

Jan 1, 1960

By F. H. Gibson

In recent years physico-chemical techniques have been applied for rapid analysis of coal and coke ash as replacements for classical wet-chemical methods. Although the classical methods are accurate, they are time consuming because many chemical separations are necessary to complete an analysis, and they require skilled analysts for accurate work (12).4 For the past several years the Bureau of Mines has applied some of the newer physico-chemical techniques in its continued search for new and improved methods at analysis. The methods of analyzing coal and coke ash evolved from this work include spectrophotometric methods far SiO2, A120, , Fe203 , TiO2, and P2O5; chelatometric titration for CaO and MgO; and flame photometry for Na20 and K2O. The methods are rapid and direct, are suitable for analyzing a group of samples at the same time in production work, and dire results with almost the same accuracy as classical procedures. With the new methods, complete analyses in duplicate can be obtained at a rate of 2 to 3 times that of conventional methods.

Jan 1, 1962

By Richard J. Mainiero

Traditional techniques for the experimental determination of toxic fumes produced by the detonation of high explosives are not applicable to blasting agents. To detonate properly, blasting agents require confinement, a significant booster, charge diameters of 3 inches (7.5 cm) or greater, and charge lengths greater than two-times the charge diameter. Without these conditions, blasting agents will not detonate at full order, leading to a misrepresentation of the gaseous products. A facility for detonating large, confined charges in a controlled volume has been constructed at the Pittsburgh Research Center’s Experimental Mine. The facility consists of a portion of mine entry (once used for full-scale mine explosion research and demonstrations) enclosed between two explosion proof bulkheads. Total volume of the chamber is 9,666 ft (274 m). The chamber is equipped with an air circulating system and is3 3vented using the mine's airflow. Up to 10-pound (4.5-kg) charges can be detonated in the chamber using a variety of confinements. For a typical test, the blasting agent is confined in a 4-inch (10-cm) schedule 80 steel pipe and initiated by a 3-inch (7.5-cm) diameter, 1-inch (2.5-cm) thick Pentolite booster. This combination of confinement and initiation yields a detonation velocity of about 4,000 m/sec for ANFO. This velocity is in line with that measured for blasting in the field. Twenty four 2-inch thick steel plates are suspended around the pipe bomb to stop shrapnel that would otherwise seriously damage the chamber. Following detonation of an explosive in the chamber, a circulating fan is run for about 10 minutes to uniformly mix the chamber atmosphere. Fumes samples are taken out of the chamber through 1/4-inch (0.6-cm) Teflon or polyethylene2tubes for analysis. The fumes are analyzed using bubblers or Vacutainers to collect samples for analysis by the analytical chemistry lab. The technique described here has been employed to determine the fumes produced by the detonation of a variety of ANFO formulations and commercial explosives. This technique may be developed as a standard test to measure fumes produced by blasting agents or may be used to provide data with which to develop a computer model that will reliably predict the expected fumes production based on chemical composition.

By K. K. Kelley, W. W. Weller

This report contains experimentally determined heat capacity data for four crystalline sulfides -- AsS , GeS , NiS , and Ni3 S₂ -- over the temperature range from 50 ° to 298.15 ° K. The heat capacity data were used to evaluate the entropies of the sulfides at 298.15 ° K. Entropies of formation from the metals and rhombic sulfur and from the metals and diatomic sulfur gas are also included .

Jan 1, 1964

By Richard E. Ray, George N. Aul, Fred Garcia, William P. Diamond

Increasing longwall panel dimensions, particularly face width in gassy coalbeds, may result in unexpected increases in methane emissions. To investigate this problem, continuous longwall face emission monitoring studies were conducted at two adjacent mines operating in the Pocahontas No. 3 Coalbed, where longwall faces were to be extended from 229 to 305 m (750 to 1,000 ft). It was predicted by regression analysis of methane emissions data from 229 m (750 ft) wide longwall faces that extending faces to 305 m (1,000 ft) would increase methane emission rates by only 7 percent (0.6 m3/min (20 cfm)), to 8.6 m3/min (304 cfm) at the VP-1 Mine. In contrast, it was predicted that extending faces at the VP-3 Mine could increase methane emissions by as much as 13 percent (1.8 m3/min (65 cfm)) to 16.1 m3/min (567 cfm). The geologic and mine design factors influencing the variation in face emissions between the two mines will be discussed.

By C. P. Bowie

[Frequent accidents in the transportation and. handling off petroleum and its more volatile products, serve as a reminder that this is indeed a hazardous undertaking and should always be conducted with due caution. On October 4, 1920, vapors in the held of the British tanks steamer G. R, Crowe became ignited and, caused an explosion which, it is reported, killed 5 men, injured. 40 others and endangered the lives of some 300 more. On November 10, 1920 the Morgan, Line freighter El Mundo was almost totally sot destroyed in New York harbor by fire caused by an explosion of gases in a fuel-oil tank. These two disastrous explosions emu emphasize the ever- present danger attending the use of petroleum products. This is also shown by the frequent occurrence of minor fires and explosions, caused by careless handling of baseline, which result in loss of life or serious injury to railroad employees, to oil-tank drivers, and to individuals in various walls of life. Statistics indicate that the lighter cuts of petroleum products, because of fire hazards, are dangerous, and are so considered by the railroad and other transportation companies. According o the Bureau of Explosives (Bar-eau of Explosives Report No. 13 p. 7) during 1919 transportation of gasoline in the United States resulted in 172 accidents, causing 2 deaths and 31 injuries, and a property loss to the extent of $687,966. Among the causes of ignition, an open light in the vicinity of the container stands out most prominently.]

Jan 1, 1920

By H. H. Schrenk, L. B. Berger, Robert L. Beatty

"INTRODUCTION Toxic oxides of nitrogen 5/ are formed or liberated in many industrial process and may constitute a definite hazard to the health of persons exposed to the atmospheres thus produced. Oxides of nitrogen occur in the gases involved in the use of explosives, in the gasoline products of welding operations in the exhaust of internal-combustion engines, in the vicinity of electrical discharges, in the combustion of nitrated materials, and in chemical process involving nitration or the use of nitric acid, Itis evident that oxides of nitrogen may constitute an occupational hazard in many industries, and therefore it is important that those concerned with the control of such hazards be equipped with a technique suitable for the determinations of oxides of nitrogen in the concentrations of,hygienic significance."

Feb 1, 1943

By E. J. Ostrowski, P. L. Woolf, J. P. Morris, Norwood B. Melcher

By injecting natural gas through auxiliary tuyeres into the smelting zone of the Bureau of Mines ' experimental blast furnace in January 1959 , the investigators succeeded in reducing the coke consumption by approximately one - third that of the base period . This caused a 30 - percent increase in pig iron production with no increase in wind rate . The maximum gas addition in these experiments was 4,665 cubic feet per ton of metal produced . Sharp reduction in gas consumption occurred when high hot blast and high wind rates were used , although the gas injection rate in percent of air blown remained constant . As the heat energy produced by burning natural gas to carbon monoxide and hydrogen is much less than burning coke to carbon monoxide , greater blast temperatures were required during the test runs . The gases produced from the methane were , however , more effective reductants ; so it was possible to increase the production rate while reducing the total heat requirements per ton of metal produced . During a base period with an all - sinter burden , before introduction of natural gas , a coke rate of 1,484 pounds per net ton of pig iron was attained , using an average blast temperature of 1,518 ° F. Gas was introduced gradually over a two -week period until an average 7 percent of the air blown was reached . During this period , the wind rate was adjusted downward to maintain a constant flow of gas in the bosh . The production rate of the furnace remained relatively constant . The quality of pig iron, however , improved as the sulfur load on the furnace was reduced as a result of the substitution of gas for coke . Blast temperatures were increased during this period from 1,518 ° F. to 1,939 ° F. , when the maximum gas addition was reached .

Jul 1, 1960

By W. W. Weller

Heat capacities of ferrous molybdate (FeMoO4) and ferrous tungstate (FeWO4) were measured over the temperature range 51° to 298.15° K. Ferrous tungstate has a lambda type heat capacity anomaly at 74° K. The 298.15° K entropies are FeMoO4) 30.9 cal/deg mole and FeW04) 31.5 cal/deg mole.

Jan 1, 1966

By James A. Morgan

FIELD MEASUREMENTS OF NOISE WERE MADE ON THE PERIPHERY OF ENCLOSURES DESIGNED, MANUFACTURED AND INSTALLED BY INDUSTRIAL ACOUSTICS COMPANY, INC. ON THE SECONDARY TACONITE CRUSHER AT THE JACKSON COUNTY IRON COMPANY PLANT IN BLACK RIVER FALLS, WISCONSIN. NOISE REDUCTION ACHIEVED BY THE ENCLOSURES WAS SUFPICIENT TO PERMIT REDUCTION OF CRUSHER ROOM NOISE TO 90 DBA, PROVIDED THAT OTHER SOURCES ARE APPROPRIATELY TREATED AND ACOUSTICAL ABSORPTION IS PROVIDED IN THE CRUSHER ROOM. SECONDARY CRUSHER NOISE WAS REDUCED 10 TO 15 DBA BY THE ENCLOSURES.

Jan 1, 1980

By Steven A. Fechner

In 1984 the Bureau of Mines cunducted mineral investigations of specific sites within the Yentna Mining District. One hundred eight placer and rock samples were taken. Reconnaissance placer samples were collected from drainages in the Talkeetna, Susitna, and Yentna River basins. The highest placer gold values were found in the historic placer gold producing creeks of the Cache-Peters Creek area. Samples taken from an outcrop in the Middle Fork of Iron Creek in the Talkeetna Mountains contained previously unreported high lead, zinc, and silver values.

Jan 1, 2011

By Thomas A. Jones

An impure variety of barite, which lends itself well to the manufacture of heavy drilling mud for oil wells, is widely distributed throughout the Ouachita Mountains in Arkansas. The ore mined in the area and used for drilling muds usually contains an average of 67 percent barium sulfate, although ores as low as 50 percent BaSO4 are occasionally used. Due to the increased demand for barite for drilling caused by the intense search for hew oil occurrences during the years 1945 and 1946, the Federal Bureau of Mines began an investigation of barite deposits in the Ouachita? Mountains in October 1946. In all, 10 barite deposits were examined, trenched, sampled, and studied during the investigation, which was terminated in May 1947.

Jan 1, 1948

By J. F. Barkley

At the request of several Federal agencies, tests were conducted on a relatively recent type of anthracite -burning equipment named the Anthratube. This device, rated at 130,000 B.t .u. per hour, was designed to burn Pea-size anthracite automatically for steam or hot-water house heating and for domes-tic hot -water supply. ACKNOWLEDGMENTS The helpful cooperation of the Anthracite Institute and the manufacturers of the equipment, Axeman-Anderson Co., Williamsport, Pa., is gratefully acknowledged.

Jan 1, 1953