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By A. T. Coumbe, I. F. Avery

The Bureau of Mines has completed a survey of petroleum pipe - lines by direct correspondence with the oil companies and the use of the records of the Interstate Commerce Commission in order to cover both interstate and intrastate systems . The review shows that crude petroleum and product pipe -lines in the United States had a total length of 152,814 miles on January 1 , 1950 , an increase of 25,463 miles since May 1 , 1941 , the time of the last previous survey . The expansion in pipe -line systems was due largely to new trunk-line construction , as the mileage built to carry refined products increased by 11,880 miles , and those intended for crude -oil transportation gained 6,193 miles . Trunk lines represented 60 percent of all pipe -line mileage on January 1 , 1950 , compared with 58 percent in 1941 . The average diameter of trunk -lines for crude oil , as calculated on the various sizes and weighted according to their respective lengths , increased to 9.8 inches on January 1 , 1950 , compared with 8.4 inches on May 1 , 1941. The mileage for lines up to 8 inches used in crude trunklines has decreased since the 1941 survey , while those of larger sizes have increased . The extensive use of large- diameter oil pipe -lines has developed since the construction of two major lines from Texas to the East Coast at government expense as a World War II emergency measure . The successful operation of these lines proved their economic advantages over smallerdiameter lines as well as their effectiveness in moving unprecedented volumes of oil during the period when tanker movements were restricted by submarine action in the Atlantic Ocean . The 24-inch diameter " Big Inch " line carries over 300,000 barrels daily of crude oil , and the 20 -inch " Little Big Inch " carried over 230,000 barrels daily of gasoline and light fuel oils to destinations where they were urgently needed . Hence , Although these lines were sold and converted to natural -gas service in December 1946 , after fulfilling their wartime mission , their record proved to the industry that significantly lower operating and investment costs per barrel -mile of oil moved could be achieved than were possible with the comparatively small lines in general use up to that time . the several major oil pipe -line projects that have been constructed since the late war are of large diameter pipe . To assure supplies and market outlets of sufficient magnitude to support such lines and provide adequate flexibility , ownership is often shared by several large companies whose transport needs are served in common . The principal recent expansion in facilities has been from supply points in Southwestern States toward markets in the North and East and to Gulf tidewater .

Dec 1, 1950

By F. N. Kissell, C. H. Elder, C. M. McCulloch

The applicability of the "direct method" for determining the methane content of virgin coalbeds was tested. Preliminary results indicate that the direct method, when applied to exploration cores, can be successfully used to estimate coalbed gas content and also approximately predict the total gas emission from a prospective mine located in the coalbed at the exploration site.

Jan 1, 1973

By A. T. Iannacchione, D. G. Puglio

The Bureau of Mines established geologic factors affecting the mining of the Lower Kittanning coalbed to aid in coalbed minability studies and examined the occurrence of "wants" (places where coal is missing) and types of unstable roof rock strata. Trends established from mapping, including prediction of areas of high methane emissions, were extrapolated to unmined areas. "Wants" in the coalbed are of two types: Erosional and depositional. Erosional features occur where north-south-trending sand-filled channels cut into the coalbed. Variations in depositional environments have caused the coalbed to "split" into several thinner units. Slickensides, commonly indicative of unstable roof, are adjacent to and on the underside of sandstone channels; they were caused by differential compaction and by soft sediment sliding along the contact between the sandstone and adjacent shale. The frequency of unstable roof also increases where the interval between the Middle and Lower Kittanning coalbed is less than 30 feet. The zones of weakness at the contacts above and below the Middle Kittanning coalbed are the controlling factors for unstable roof in these strata. Methane emissions from the coalbed are controlled primarily by depth, fracture permeability, and rank of coal. Local geologic factors are coalbed thickness, associated rock strata, structure, and proximity to outcrop.

Jan 1, 1979

By J. J. Demeter

Anthracite from the four producing regions in Pennsylvania was both ashed in the laboratory and burned on a chain-grate stoker to determine the sulfur-retention properties of its ash. The retention of sulfur in laboratory-prepared anthracite ash was shown to be related to ashing temperature and to the amounts of sulfur and calcium present in the coal. At the usual laboratory ashing temperature of 750° C sulfur retention ranged from 0.8 to 13.2 percent of the total coal sulfur. Sulfur retention in the ash was negligible, o to 0.3 percent, at 1,200° C, which is the thermal decomposition temperature of calcium sulfate; thus calcium sulfate does not form and cannot serve as a sulfur-retaining agent. In several tests the anthracite was mixed with 6 or 10 percent dolomite prior to firing in the chain-grate stoker. The dolomite did not improve sulfur retention owing to the high temperature in the fuel bed. Sulfur retention was, however, related to the unburned carbon in the ash. The relationship of the percentage of original coal sulfur retained in the ash (Y) to the percentage of the original carbon in the coal remaining in the ash (X) is expressed by Y = -0.579 + 0.914X. The percentage of sulfur retained is almost directly proportionate to the percentage of original coal carbon in the ash.

Jan 1, 1968

By Frank B. Fulkerson

A study was made of the economic factors governing silver production in the Coeur d'Alene mining region, Shoshone County, Idaho. Production and other statistics were analyzed. It was concluded that if the rapid rise in the open market price that began late in 1961 continues, greater production of the metal should result from the mines of the Coeur d'Alene mining region. However, the output gain would be limited, because costs per ton of ore mined would rise as production was increased beyond optimum capacity. Advances in the price of silver would increase the size of ore reserves by making some marginal ore profitable to mine and by providing greater funds for exploration projects that might result in discoveries adding to the reserves. Output of byproduct silver from Lead-zinc mining probably will not exceed 4.3 million ounces, judging from the trend from 1946 to 1961.

Jan 1, 1964

By Frank B. Fulkerson

A study was made of the economic factors governing silver production in the Coeur d'Alene mining region, Shoshone County, Idaho. Production and other stat is tics were analyzed. It was concluded that if the rapid rise in the open market price that began late in 1961 continues, greater production of the metal should result from the mines of the Coeur d?Alene mining region. However, the output gain would be limited, because costs per ton of ore mined would rise as production was increased beyond optimum capacity. Advances in the price of silver would increase the size of ore reserves by making some marginal ore profitable to mine and by providing greater funds for exploration projects that might result in discoveries adding to the reserves. Output of byproduct silver from lead-zinc mining probably will not exceed 4.3 million ounces, judging from the trend from 1946 to 1961.

Jan 1, 1964

By R. V. Lundquist

The compound 2Na2O?3CaO?5Al2O3 occurs as a minor phase in lime-soda sinters prepared for extracting aluminum from siliceous aluminum-bearing materials. About 99 percent extraction of sodium and aluminum from synthesized 2Na2O.3CaO.5Al2O3 was obtained in solutions of NaOH-Na2CO3 at leaching temperatures of 50° C and above. Extractions in water were low because insufficient NaOH was generated by hydrolysis. Extractions in NaOH solutions were limited to about 80 percent owing to the precipitation of hydrated calcium aluminates. Rapid extractions of 100 percent were obtainable in NaaC03 solutions, but the subsequent rapid precipitation of alumina trihydrate caused losses in alumina recovery.

Jan 1, 1965

By M. R. Geer

Three coals from the Wilkes on - Carbonado district of Pierce County , Washington , were subjected to washability analyses to estimate the amount and quality of washed coal obtainable . Because the coals were unusually difficult to clean , the washability examinations were supplemented by table tests , tests in dense - medium cleaning units , and flotation tests . None of the coals could be reduced to the desired 10 percent ash by tabling and the response to flotation by two of them was poor . Dense -medium treatment provided coal of the desired quality , but with the most difficult coal the recovery efficiency was lower than usual .

Jan 1, 1964

By H. B. Humphrey, F. E. Cash

The Birmingham coal-mining district of Alabama has many local physical conditions that contribute largely to the proble of preventing coalmine fatalities . Coal : nes of Alabama have been under the supervision of the State mine inspector since 1892 , and reports have been made with increasing completeness since that time . The U. S. Bureau of Mines has maintained a station of the safety division in the district since 1912 to cooperate with operators and the State in the advancement of safety in mining . A description of conditions in regard to fatal accidents as they have been and as they now are in Alabama , compared with the entire United States , will indicate the progress that has been made and that should still be made in reducing fatal mine accidents .

Sep 1, 1930

By Daryl R. Tweeton

The Bureau of Mines compared the effects of surface-active chemicals with those of pure water on core-drilling rock and quartz and on fracturing quartz. The objectives were to determine if these chemicals assist drilling and fracturing rock and if zeta potential control was worth pursuing as an aid to full-scale drilling. All tests were performed in the laboratory. No significant increases in drilling rates were observed for 1 to 10,000 ppm Al (as AlC13) in flushing water when drilling microcline or serpentine, nor for 1 to 10,000 ppm Mg (as MgC12) when drilling microcline or marble. Concentrations near those giving a zero zeta potential were used with microcline and marble. A 50-pct rate increase was observed for drilling quartz in 0.7 ppm oleylammonium acetate, which gave a zero zeta potential. No other concentrations were used. No effect on the tensile strength of quartz thread in 0.05 ppm Al (as AlC13), which gave a zero zeta potential, was observed. Heptanol, reported to give a zero zeta potential on quartz, did not reduce the bending strength of small quartz bars below that in water. These generally negative findings raise doubt about the usefulness of zeta potential control in full-scale drilling. The results, combined with previous studies, suggest that controlling physical properties of drilling fluids, such as viscosity, is more useful than altering chemical properties.

Jan 1, 1976

By R. V. Lundquist, H. Leitch

Sodium aluminate is the principal aluminum compound formed in the sinters prepared by the lime - soda sinter process for recovering aluminum from silicate source materials . The properties and characteristics of this compound were studied to improve the efficiency of the process . Crystalline sodium aluminate was prepared by sintering stoichiometric quantities of soda ash and calcined alumina for 1 hour at 1,250 ° C. The extent of aluminum extraction from sodium aluminate was determined in water and in solutions of NaOH and Na₂ CO3 . Nearly complete extraction of aluminum from sodium aluminate was achieved only in solutions containing free NaOH in excess of that supplied by the salt through hydrolysis . About 42.2 to 68.8 percent of the aluminum was extracted in water or in solutions of Na₂ CO . The precipitation of alumina trihydrate from sodium aluminate solutions was shown to be part of a continuous , reversible reaction according to the equation Al (OH ) A1 (OH )3 + OHThe reverse reaction dissolves alumina trihydrate in NaOH solutions to produce sodium aluminate . Approximate equilibrium concentrations were determined for the reaction at 30° , 50 ° , and 70 ° C. False apparent equilibrium conditions for the dissolution reaction appear when only a small excess of alumina trihydrate is present in the NaOH solutions . A large excess of alumina trihydrate must be present before the true equilibrium point is assured . The engineering significance of the data is summarized , showing controls that should be exercised for a successful and efficient process .

Jan 1, 1964

"The U.S. Bureau of Mines established on August 15, 1983, The Generic Mineral Technology Center for Respirable Dust (Dust Center) within the Mining and Mineral Resource Research Institutes (MRIs) at The Pennsylvania State University and West Virginia University, and in association with participating MRIs at Massachusetts Institute of Technology and the University of Minnesota. In 1986, Michigan Technological University (MTU) was awarded a grant through the Dust Center. The center's research program has been developed with recognition of the stated objective of the Federal Mine Safety and Health law, which is ""... (to) permit each miner the opportunity to work underground during the period of his entire adult working life without incurring any disability from pneumoconiosis of any other occupation-related diseases..."" The Dust Center's program is designed to foster an accelerated attack through fundamental research on problems confronting the control of respirable dust in mines. The interactions of the universities and the research program components in the characterization of coal seams, respirable dust particles and the workers lungs are depicted in the logo of the Dust Center.The primary goal of the Dust Center is to reduce the incidence and severity of respirable dust disease through advancing fundamental understanding of all aspects of respirable dust associated with mining and milling, and the interaction of dust and lungs. The Dust Center's research program explores these concerns with the objective of refining existing strategies and developing new respirable dust control techniques that are consistent with the fundamental dust-lung interaction processes that lead to mine worker disability. The work concentrates on: (1) control of dust generation; (2) dilution, dispersion and collection of dust in mine airways; (3) characterization of dust particles; (4) interaction of dust and lungs; and (5) the relationship of the mine environment, geology, and seam characteristics to dust generation and mobility. The fundamental aspects of this work are applicable to the control of respirable dust problems in both hard rock mines and coal mines, and to other dusts such as those generated by diesel equipment. Achieving the Dust Center's goals also involves the training of engineers and scientists, graduate students, and undergraduate students through their respective institutions, and technology transfer to industry. The distribution of personnel in the various universities are presented in Table 1. A directory of Dust Center principal investigators is presented in Appendix 1. A summary of degrees granted and mineral sector employment is presented in Table 2. The subjects of theses developed under the various research projects are presented separately in Volume 7. The center research is fully compatible and complementary with the existing and ongoing U.S. Bureau of Mines activities (see Volume 2). Additionally, the expertise and facilities of the NIOSH--Division of Respirable Disease studies are available as a result of the existing relationship between NIOSH and West Virginia University. Figure 1, Respirable Dust Center Projects and Activities, presents the various projects in the five major areas of investigation and the scope of characterized dust samples, the suite of tests, the sampling and dust generation methods, and the size, chemical and mineralogical analysis performed in the center. Table 3 presents a summary distribution of the 95 publications and presentations that have emanated from the center. In addition there are more than thirty presentations made at each annual Dust Center review meeting. The titles, authors and location of presentation for publications supported by the Dust Center are presented in separate publication volumes for 1984 (Volume 3), 1985 (Volume 4), 1986 (Volume 5) and 1987 (Volume 6)."

Jan 1, 1988

By W. W. Simpson

During cyanidation of mercury-bearing gold-silver ores, significant amounts of mercury are extracted. The presence of mercury decreases. gold loading and increases mercury stripping time on activated carbon, complicates fire refining of the gold cathodes, and creates a potential health hazard. Addition of calcium sulfide (CaS) to the cyanide leach slurry precipitates the solubilized mercury but also some silver. The Bureau of Mines investigated silver loss during CaS precipitation of mercury. Addition of 0.1 lb CaS per short ton ore to a mercury-bearing gold-silver ore precipitated both mercury and silver. However, if copper was added with CaS, or if the ore contained copper, much of the sil-ver loss was prevented. Addition of 235 ppm Cu with 0.1 lb/st CaS, prior to carbon-in-pulp adsorption, resulted in 89-to 97-pct, 80-to 91-pct, and O-pct adsorption of the solubilized gold, silver, and mer-cury, respectively, on the activated carbon.

Jan 1, 1986

By John A. Breslin

Size distributions and concentrations of particulates emitted from diesel engine exhausts were measured with cascade impactors. Samples were taken from the exhaust of two types of engines using three types of fuel and operating under five different engine speed and load conditions. The measured mass median diameters of the diesel particulates were typically about 0.3 um. There was no significant difference in mass median diameter between engines or fuels and only a slight dependence on operating mode. Concentration measurements ranged from 14.2 to 250.9 mg/cu m, and calculated mass outputs, from 52 to 3,443 mg/min. Significant differences in mass output were found between engines, fuels, and especially between different operating modes. The quantity of clean dilution air that would be required to reduce the particulate mass concentration below the 2.0 mg/cu m respirable dust standard for coal mines was greater than the dilution air required to meet the standards for noxious gases for both engines tested.

Jan 1, 1976

By R. V. Ramani, R. L. Grayson, R. L. Frantz, V. A. Marple, W. R. Myers, K. L. Rubow, Mutmansky. J. M., T. J. Stobbe

"An investigation of protocols for research performed from 1953 to 1988 on pneumoconioses (with emphasis on diseases related to coal and silica) was conducted in the Generic Mineral Technology Center for Respirable Dust. In addition, interviews were conducted with prominent U.S. medical researchers, aerosol scientists and engineers in government, industry, and universities to determine dust sources, dust preparation methods, laboratory protocols, and determinant variables related to in vitro and in vivo research and assess the comparability of results.Since the original report on the protocol project, additional research regarding free radical existence in freshly produced dust particles and the shape and contamination of particles generated for research purposes has further heightened scientists' concerns. As indicated by current research, fresher dust particles and those with more angular shapes may have a different level of reactivity in biological systems than do older or more rounded particles. Therefore, research on dust preparation methods for biomedical studies was undertaken and will be outlined here.Results of protocol review and interviews are summarized. Research on size reduction methods and their particle characteristics plus some recommendations concerning dust preparation methods and reporting in biomedical publications are also presented. Recent evidence indicates that these recommendations may be of importance in comparing and interpreting research results."

Nov 1, 1995

By D. Harrington

Although it is impossible to give definite final figures at this time on Nation-wide accident occurrence in 1933 , enough data are at hand to indicate that the progress in safety in the mining industry, which first became apparent in 1930 and was accentuated in 1931 and 1932 , was continued and much improved in 1933. This improvement was of considerable magnitude in mining both bituminous coal and anthracite but was not so great in other branches of the mining industry . While the volume of work done in all phases of mining increased in 1933 over that in 1932 , the exact amount of the increase is not yet known . Usually increased activity in mining is accompanied by even greater increase in the rate of occurrence of accidents to the workers , but happily it appears that this " rule " was not operating in 1933 --at least in the coal -mining industry .

Oct 1, 1934

By Clarence O. Babcock

This Bureau of Mines publication presents guidelines for mining near surface and underground bodies of water. The guidelines were based on information developed under contract in three phases of study, as follows: (1) Collection and documentation of data from worldwide sources; (2) application of existing guidelines, foreign, Federal, and State, to case histories of previous inundations; and (3) development of recommended guidelines for underground coal mining near bodies of water aimed at maximum efficient utilization of underground coal resources consistent with minimizing inundation hazards. While the contract guidelines were for the mining of coal seams, they may also be used for mining any tabular sedimentary mineral deposit. Tables are given for the determination of the size of coal pillars needed; for other bedded deposits, similar tables could be determined based on their strength properties.

Jan 1, 1977

By Henry E. Blake

The Bureau of Mines has been engaged in a continuing research effort to develop processes for increasing the recovery and utilization of fluorine from low-grade resources. This current research has shown that over 98 percent of the fluorine in phosphate rock is extracted when the ore is treated with excess phosphoric acid in the presence of water vapor at 150° to 180° C. More than 80 percent of the fluorine can be recovered as fluosilicic acid, which can then be converted to commercially useful hydrogen fluoride or fluorspar by previously developed Bureau processes. Extraction of P205 from the ore was about 98 percent in batch tests and 90 percent in semicyclic tests.

Jan 1, 1974

By Michael J. Magyar

The Federal Bureau of Mines has developed a hydrametallurgical method to recover aluminum, aluminum oxide, and fluxing salts from aluminum salt slags. The slag is leached with water at room temperature to produce a saturated brine slurry. Screening of the slurry yields an aluminum-rich fraction that can be returned to the dross furnace. The remaining slurry is vacuum filtered, yielding a clear brine solution and an aluminum oxide filter cake. Evaporation of the clear filtrate produces a high-purity fluxing salt for reuse in the dross furnace. Over 80 pct of the metallic aluminum is recovered in the aluminum-rich oversize fraction, while essentially all the fluxing salts are recovered by evaporation. This report contains the final results of an investigation on a process research unit scale, an economic evaluation of the method, and recommendations to further improve the process.

Jan 1, 1979

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