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By Mackenzie Burnett

The Brattice Window Method was used to measure the leakage rates of a total of 42 ventilation stoppings in 8 hardrock mines. Various types of stopping construction were evaluated. The following types are listed in order of decreasing effectiveness: 1) Cinder block, 2) Timber and mortar, 3) Timber and polyurethane foam, and 4) Timber and brattice material. There are slight differences in the effectiveness of the first three types, while the timber and brattice type is substantially inferior to the others. The repeatability of the Brattice Window Method was found to vary with physical conditions in the mine such as stopping location with respect to intersections, regularity of drift cross section, and the presence of hardware such as air and water pipes, timber sets and wire mesh. The Brattice Window Method is viewed primarily as a tool for estimating and comparing stopping leakages for the purpose of determining where repair efforts should be concentrated. A laboratory test program resulted in the derivation of several "rules of thumb" for employing the Brattice Window Method, which will aid in securing accurate and repeatable data.

Jan 1, 1979

By Sam S. Taylor

In most oil fields, natural gas is the major source of energy causing flow of oil to the well. The amount of gas produced with the oil generally exceeds actual energy requirements, so that in time the gas reserve of the field becomes seriously depleted and the oil production must be stimulated by some auxiliary means. One of these is to repressure the oil formation with natural gas; or, where a as supply is not available, often air is used. Although air is a cheap and convenient repressuring medium, its use sometimes is attended with several disadvantages. First, the return air-gas mixture decreases rapidly in fuel value, often until it can be used no longer as a source of power. At the same time, explosive mixtures may result if recycling is used, causing hazards to life and equipment. Second, sortie fields experience considerable trouble with the formation of emulsions which become increasingly difficult to treat. Although there is no definite proof that air repressuring always causes these emulsions, many operators are convinced that this is the case. The Petroleum Experiment Station of the United States Bureau of Mines at Bartlesville, Okla., has been interested in problems connected with air-repressuring for a number of years. Some time was spent in studying the so-called "bad gas"--return mixture of low fuel value. However, it appeared impossible to attack the problem successfully from this angle, and an approach was made through a laboratory-scale study of direct oxidation of crude oil.

Jan 1, 1934

By Donald I. Kurth

The Bureau of Mines conducted experimental work on comminuting coal. The size distributions of coarse fragments and fine particles were obtained under different modes of energy application--drop, impact crushing, wedge impact, compression, and shear tests. Four levels of energy application were used in the impact crushing and wedge impact tests. Airborne dust and respirable air-borne dust distributions were obtained for the impact crushing and wedge impact tests. Analyses of nonairborne dust and coarse fragment-fine particle distributions were carried out on impact, wedge, compression, and shear tests. The experimental size data on nonairborne dust were fitted to normal, log-normal, power law, Weibull, log-Weibull, and exponential distribution functions. Both the nonairborne dust and the coarse fragment-fine particle size distributions are best described by Weibull distributions. For the impact crushing tests, mean product size was found to be inversely related to specific crushing energy. The particle counts in a given size range of airborne and nonairborne dust were found to increase with increased input energy and specific crushing energy. However, in another sense the particle distributions were independent of energy level; that is, the percent-ages in a given size range were approximately constant regardless of energy level. Respirable airborne dust was related to respirable-size nonairborne dust by a power law.

Jan 1, 1975

By R. G. Travis

1. Reserve estimates have been made for eight coal beds in Monongalia County, W. Va., but only the Pittsburgh, Sewickley, and Upper Freeport beds are important at this time. The Pittsburgh, Sewickley, Waynesburg, and Upper Freeport beds contain the largest recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 3,526 million tons as of January 1, 1954. Of this total, 3,294 mil-lion tons is in beds 28 inches and more thick. Areas in each bed except the Pittsburgh were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

By M. M. Wong, J. E. Klosterman

Scrap beryllium chips ( nominally 96 to 97 percent Be ) were electrore fined in a prototype cell with 408 lb of electrolyte composed of 52.4 mole - percent LiCl , 36.3 mole - percent KC1 , and 11.3 mole - percent BeCl2 . The cell temperature was 500 ° C. In a typical 10-3 /4 - hour deposition cycle , 0.415 pound of metal was produced ; the metal contained impurities in parts per million as follows : C , 700 ; 0 , 610 ; Al , 34 ; Ca , 32 ; Cu , 20 ; Fe , 25 ; Mg , 9 ; and Mn , 23 . Operation of the prototype cell for 2 years demonstrated that adapting the electrorefining process to an enlarged scale of operation presented few difficulties in mechanical functions , maintenance of optimum operating conditions , and control of product purity . After the spent anode feed was leached in a 5 - percent nitric acid solution and the fine - sized particles were removed , it was recycled in some tests . The metal produced was somewhat higher in impurities than metal from the fresh scrap chips .

Jan 1, 1964

By P. A. Lawless

The objective of the research performed A for the Bureau of Mines on this contract was to develop a portable instrument for the detection of carbon monoxide (CO) in a mine environment. The desired characteristics were sensitivity and specificity for CO with a stable calibration. The sensor of the instrument was to be of metal oxide composition, requiring low power for compatibility with the types of batteries presently used in personal equipment in mines. The solid state design was also desired for ruggedness and small size. A key design feature of the instrument was to be provided by adherence to the intrinsic safety design requirements for electrical equipments operated in potentially exposive mine atmosphere. The Research Triangle Institute has prior experience in developing a solid state oxygen sensor using a thin film of zinc-oxide (Ref. 1) and experience in fabricating thin film devices. Solid state sensors utilized by other workers (Refs. 2, 3, 4, 5, 6) have included metal and semiconductor films and crystals of materials like carbon and aluminum oxide for the measurement of water vapor in the air and have relied upon measuring resistance and capacitance changes in the sensor in response to adsorbed vapors or gases. Since the effect of carbon monoxide in changing the resistance of various materials such as molybdenum, platinum, and zinc oxide had been reported (Refs. 7, 8, 9, 10), the requirements appeared to be realisable, although it was recognized even at the inception of the work that specificity to carbon monoxide might require the incorporation of more than one sensor.

Jan 1, 1976

By M. E. Tyrrell

Mixtures of zirconium diboride and iron, cobalt, and nickel were resistance sintered to high-density compacts using modified electric welding equipment. To evaluate the use of iron, cobalt, or nickel as binders for zirconium diboride, the sintered compacts were examined in polished section and tested for crushing strength, hardness, microhardness, oxidation rate, and resistance to mechanical shock. Each of the zirconium diboride-metal mixtures produced brittle cermets, but the hardness was generally satisfactory. The iron- and cobalt-bonded cermets exhibited rather poor oxidation resistance. Cobalt provided the least brittle bond, and nickel, the hardest and most resistant to oxidation. Iron tended to form chalky compacts with low resistance to mechanical shock.

Jan 1, 1963

By E. L. Garton

The Bureau of Mines for a number of years has been conducting an investigation of crude petroleum from producing fields in the United States and the Western Hemisphere and has published a series of reports on these fields. Analyses of crude-oil samples from many oil fields of Oklahoma are given in Bulletin 2913. Analyses of 21 representative crude oils from various producing zones of the Oklahoma City field are given in this report. A close study of the analyses reveals very few differences in the general characteristics and chemical properties of these oils.

Jan 1, 1932

By F. G. Miller

[Petroleum technoloF;istz and 1 rot-re s s ive OT e:?ztors. con stantl;, are striving to increase the percentage of oil that y to recovered from reservoir rocks throe::;:: wells. The exhaustive studies that have been made of the function of natural r:; as in t h-_ T r odI action of oil, for cx<n.mTnle, have aidedd of.erators greatly in incroasin,&apos; the q-:Arrntity of oil recovered from reservoirs. i.rtural gas dissolv3d in ar--d otinerwwisa &apos;1s&apos;.,ocintjd under rre3suro with oil in roscrvoir roci.s, howover, i:; not the only source of energy available for moving oil through sa&apos;:&apos;l to wells. l becoming "reservoir-energy conscious&apos;t engineers hr-vo -d o^.rued t}:-Lt in many petroleum reservoirs the edgewater flanking t -,e oil accum.-,lation conetitutos a potential source of onergy capable, tL-ou;_h rro? gr control, oil&apos; increasing oil-recovery efficiencies materially. i o ]enter is ti-.-,, on-cronchinunt of water into the oil- and gas--fillod ?art of the reservoir considered as an evil to be combatted by devious mot&apos;:r:ci :i,.t r,ttL er a natural conseque::c4, incident to the withdrawal of oil nna gas from the wells, that nay be T.usod advantrt eou ;ly in lonr`t}toning tr e r&apos;lowin g lift of wells a.nd, i norcas in:; the economic recovery of oil and Little is known about the by which water off: oratos in driving nil throe:gh reservoir roc:-.:,, nd i:. a scorcity of rubli:;Lad informs-¬t .on nn rates of :)Ov.:m.,:- t of : r.tcr ..at v:1:11 res,-_lt in ^r i-nu oil recoveries. Bureau of :fines engine_:? ; - reciate. the r,aucity of scientific knowledge or. the &apos;test methods of a,r.lying the natural water arive to in¬crease oil-recovery efficiencies ant ,i.;?l __-itir?,~ ting irties that will, they hope, Contribute to t.1&apos;.e T ros?Jr.t. small _ %nd of information now av tilable on tt:e cubjoct. This r».crt a oyno-.::is or brief comrilnt.ion of r,ublished data and thought accuinulnt.~d so far, to la)or;~.tory ox-:erimnntrr¬tiorn and, further rosoarch on the z_rrinciplos unri;rlyir..g the natr.rr+1 eater drive no it nffocts oil recovery. :Lie writer:: Lore that t.i.c cx-nositiorn of a?rzilable inforr-at ion i rcs?r.toi in the rernrt r .-II .i ,.1rtt cor_jt_-i:ctive tho.-_.I_t and efforts loadir,-z to -:ard more con.r .ote extraction n;&apos; o tl from reservoirs.]

Jan 1, 1938

By O. M. Bishop

From October 1943 to March 1944, the Bureau of Mines conducted core drilling at the Victory fluorspar mine, Hardin County, Ill. to test the Fredonia limestone and the included sub-Rosiclare sandstone zone beneath the existing stopes. Twenty-one vertical holes were drilled to an average depth of 60 feet. Ore was penetrated in six holes. Since its discovery in 1927, the Victory mine has produced approximately 5 percent of the total fluorspar mined in the United states after that date. The ore discovered in the early mine development is now exhausted, except that contained in pillars drifting to the northeast has partly developed one substantial ore body, and company drilling has indicated another nearby. The increasing need for fluorite for war use in 1943 suggested the desirability of mining the pillars, provided it could be established that no ore beds existed below the stopes or in areas to which access would be obtained through the present workings. This work describes the work accomplished during the project and presents the data obtained.

Jan 1, 1948

By Oliver Bowles

"Asbestos" is not the name of a distinct mineral species but is rather a commercial term applied to fibrous varieties of several minerals. The origin and significance of names applied to asbestos by early writers are discussed in the section devoted to sources of supply and terms employed in ancient times. VARIETIES The most useful variety of asbestos is chrysotile, a fibrous serpentine the composition of which is expressed by the formula H4Mg3Si209. Chrysotile is characterized by a strength and flexibility that permit the use of the longer fibers for spinning. The bulk of the world production of both long and short fibers, is of this variety.

Jan 1, 1935

By Albert A. Munsch

The Munsch National First-Aid Instructors Association had its inception during the teaching of a Federal Bureau of Mines first-aid instructors&apos; class at McPherson, Kans., under a cooperative plan of first-aid training. Upon completion of- the course on July 1, 1938 members of the class organized the charter chapter of the association under the name of McPherson (Kans.) District Charter Chapter No. 1. On July 1, 1941, 3 years after the founding of the association, there were 15 chapters in the national council -7 in Kansas, 3 in Oklahoma, 2 in Texas, 2 in New Mexico, and 1 in Arkansas. Although the pioneer work of the association was done in the petroleum industry, the plan will be of even greater benefit to a district in which there are various types of plants, mince, and operations of the mineral and allied industries. ACKNOWLEDGMENTS The writer appreciates the cooperation and assistance of the following persons: S. P. Redfearn, safety engineer, Globe Oil & Refining Co. and affiliated companies, Wichita, Kans., and H. (Chief) Moore supervisor of safety meetings, Shell Oil Co., Inc., McPherson, Kans., for their untiring efforts and enthusiasm in organizing an- attending the first class, organizing three other classes, and helping to plan the work of the association

Jan 1, 1942

By Uldis Jansons

This report evaluates the economic Mining feasibility of four selected mineral deposit types that can be anticipated to be found in (d)(2) lands in the western Brooks Range, Alaska. The major assumption made for this study is the availability of a rail system for transporting equipment and concentrates for the base metal mines. Commodity prices used are those in existence in July 1976. Mine models were established based on known deposits and then evaluated. A lead-zinc-silver-barite deposit for which grades were available but ore reserves were assumed would require approximately 25% higher ore grades or higher metal prices to yield a 15% discounted cash-flow rate of return an the investment if mined at a rate of 10,000 tons per day open pit methods. Large copper-zinc mineral deposits could be mined economically at rates either of 5,000 tons per day underground or 10,000 tons per day by open pit methods. A high-grade copper deposit require a copper price of over one dollar ryes pound to yield an economic profit to be mined at 2,000 tons per day by underground methods. A small high-grade gold underground mine would require a gold price of about $295 per ounce to yield a 20% discounted cash-flow rate of return on investment if all new mine equipment were used and if existing labor rates were paid: Enterprising mining groups operating as partnerships might be able to operate this mine profitably at a gold price of about $152 per ounce, perhaps slightly less.

Jan 1, 2012

By H. C. Miller

For nearly a score of years the American petroleum industry has faced the problem of maintaining its economic structure while oil -producing potentialities greatly exceeded the increasing market demand for oil and its products . However , the combination of maximum civilian demand with rising defense requirements caused an all - time peak in crudeoil production in the latter half of 1941 , with a daily production (as estimated by the Bureau of Mines ) of 4,139,000 barrels in December - an increase of 16 percent over the daily production of 3,573,000 barrels in December 1940. In the event of a long war , a continuing , steady, and adequate supply of petroleum and its products for military and required civilian needs is essential, and the efficiency of recovery of oil from natural underground reservoirs will have to be maximum. Whereas it may not be possible to increase production in some fields , the output from others may have to be drawn at a much faster rate than formerly . More than 10 years ' experience in operating oil fields under proration control has demonstrated to petroleum engineers that some of the efficiency of recovery of oil from reservoir sands and rocks is sacrificed if the oil and gas are withdrawn at too . rapid a rate . As petroleum is an irreplaceable natural resource for which suitable substitutes probably will not be available in desired quantities for many years , any producing method that jeopardizes the quantity of oil that may be recovered from underground reservoirs must be considered at this time of declared war against aggressor nations as conflicting with the best interests of national defense . At best, the efficient recovery of oil is a complex problem . It involves not only a knowledge and application of the fundamentals of fluid flow through porous mediums, but the sources of energy responsible for the movement of oil and gas through reservoir sands and porous rocks to wells must be known to determine the best practices for extracting these hydrocarbons . Reservoir energy is of two kinds - (1 ) water under hydrostatic head underlying the oil in the extraneous parts of the reservoir system and ( 2 ) natural gas under pressure as "free " gas in the reservoir or in solution in the oil . Inasmuch as the efficiency of oil recovery depends largely on the manner in which reservoir energy is used to move oil through reservoir sands and porous rocks to wells , optimum practices for withdrawing the oil cannot be determined until it has been established that the oil in the reservoirs is being forced to wells by an internal gas expansion, by a natural water drive , or by a combination of gas expansion and water drive . There is a fundamental difference in the performance characteristics of gas - expansion and water - drive reservoirs . In a strictly gas - expansion reservoir the energy available to move oil and gas through the porous formations to wells results solely from gas pressure , which is maximum when the reservoir is tapped by the first well . Pressures decline as oil and gas are withdrawn ; consequently, the energy available for moving oil and gas through the oil - bearing formations to wells decreases with production . Curtailing the oil - production rate or shutting in gas - expansion reservoirs entirely will not act to replenish energy previously used in the production of oil and gas ; in their operation , therefore , it is especially important not to waste reservoir energy - the production of oil with high gas : oil ratios will be reflected in lower ultimate recoveries of oil .

Apr 1, 1942

By James W. Townsend

The Vicksburg mining property lies in the southeastern foothills of the Star mining district, Beaver County, Utah (fig. 1). Within a few miles of the Vicksburg mine, lying in a semicircle from south to northwest, are such past producers of lead-silver ores as the Moscow, Hoosier Boy, Red Warrior, Wild. Bill, Harrington-Hickory, and many others. Farther to the north, in the San Francisco district, are the famous Horn Silver and Cactus mines. The formation at the Vicksburg property consists of interbedded limestone, shale, and dolomitic limestone. These beds have been metamorphosed by the intrusion of irregular masses of porphyritic igneous rocks grading from quartz-monzonite to granodiorite. Ore deposition is in north-trending fissures of sheeted zones, contact metamorphic in type. These depositions were subsequently altered to gossan. A preliminary investigation of the Vicksburg property involving surveying, mapping, and sampling was made by W. A. Young and F. H. Gunnell, engineers of the Bureau of Mines, in the fall of 1946. As a result of the investigation, a project was set up to investigate the possibility of ore occurrence at greater depth on the fissures under the mineralized zone by diamond drilling.

Jan 1, 1950

By B. B. Letson

The heats of formation of lithium chloride and lithium oxalate were determined with the aid of a Bureau-developed, glass Dewar-type solution calorimeter which uses thermistors as its temperature sensing element. Values obtained at 298.15° K were -98.38 ± 0.54 kcal/mole for lithium chloride and -329.02 ± 0.79 kcal/mole for lithium oxalate, using graphite as the standard state for carbon.

Jan 1, 1965

By R. W. Van Dolah, N. E. Hanna, F. C. Gibson

Measures that were taken to eliminate noise resulting from explosives work at the Bureau of Mines facility at Bruceton , Pa . , are described . A method for monitoring sound transmission characteristics of the atmosphere and control of the explosives testing is presented as a noise control measure that offered partial relief during the period in which the modifications were made . Design details of the replacement gallery , used for permissibility testing of explosives , and the modifications of four types of bombproofs are given . Operation of the closed facilities are completely satisfactory , and the noise problem has been entirely eliminated .

Jan 1, 1964

By K. S. Gritton

The Bureau of Mines investigated the feasibility of numerlcally modeling the sorption of cobalt, a vulnerable strategic and critical metal, from spent copper leach solutions in a multiple-compartment ion-exchange (MCIX) column. Equilibrium resin loadings, cobalt-sorption kinetics, and resin-fluidization characteristics were determined in simple laboratory tests, and a numerical model was developed to predict cobalt extraction and the MCIX-column resin inventory based upon the test results. The model was implemented on a microcomputer to approximate the solution to the set of differential equations that govern model performance. Results compared very well with data from 12 pilot-scale MCIX-column experiments. The average difference between predicted and actual cobalt extractions was 3.2 pct; the maximum difference was 9.3 pet. The actual and predicted resin inventories differed by an average of 5.8 pet, and the maximum difference was 12.0 pct.

Jan 1, 1987

By F. F. Aplan

Separation of the slightly soluble minerals (Ksp? 10-10), one from the other is one of the more difficult tasks confronting flotation engineers. This study has focused on means of separating such prominent members of this class as scheelite, fluorite and calcite from one another. Some experimental work has also been done on the minerals magnesite, dolomite and apatite. Carboxylic acid-type collectors are commonly used industrially to float all of these minerals. Thus, the problem at hand is to ascertain means of achieving selectivity between minerals known to respond rather similarly in flotation. Four techniques have been proposed for the separation of minerals of this class from each other: 1. Control of potential determining ions 2. Use of stereo-specific collectors 3. Use of flotation rate differences 4. Use of selective activating and depressing compounds. This study was directed toward a cursory evaluation of each of these techniques, and each was found to be a possible method of achieving selectivity. Stereo-specific collectors -- those whose parking area may closely match the available adsorption site on one mineral but not on another -- are a possible means of achieving selectivity between scheelite, fluorite and calcite. Stereo-hindered carboxylic acid salts and sulfonates all show selectivity between the three minerals tested. Separations also appear to be possible by the controlled use of the lattice ions (e.g., Ca and [W0=4] for scheelite, CaW04), H+, [OH-, C0-3 and HCO=3]; all of them ostensibly potential determining in the systems studied. Flotation rate differences of the minerals as a function of pH under conditions of starvation collector usage also showed promise. Scheelite and fluorite float most rapidly with sodium oleate in slightly acidic (pH 4-7) solutions whereas calcite floats most rapidly near pH 10. Use of Mn++, Pb++, or other heavy metal hydroxy complexes as activators was seen to effect each of the slightly soluble minerals differently. This is in sharp contrast to the oxygen containing, relatively insoluble minerals, where all minerals respond in a similar manner to such activation procedures. Results indicate that all four methods outlined above may potentially be used to achieve flotation separation of the slightly soluble minerals. More extensive research should be undertaken to detail the spcific applicability of each of the procedures and to make a more complete evaluation of the effect of collector type and concentration, mineral type, pH and size effects.

Jan 1, 1983

By Thomas Fraser, J. D. Davis

"INTRODUCTION Preliminary tests of the Oyon coal constituted part of a wartime exploratory and development program in which many agencies participated. The general objective was to find new and adequate source of fuel and other raw materials for greatly expanded industry.The Oyon coal field, known for at least a hundred years to the mining people of Peru, offers a possible source of high-grade process fuel for the growing metallurgical industries of South America and the Pacific coast. Santolalla 4/ reports that low-volatile coal from this region was used in local smelting operations as early as 1850. It has been mined in very small quanti¬ties for many years and used in neighboring mining camps and villages. Small quantities are regularly used at Oroya for the manufacture of carbide, and in recent years small-scale coking operations in specially designed ovens in the region have demonstrated that these coals will make dense coke.During this long period of desultory operations many small openings have been made scattered over a wide area in this general region, indicating very extensive occurrence of the coal measures, although systematic exploration work has not been undertaken. However, current development work of the Banco Minero del Peru has opened up several substantially parallel highly inclined or vertical beds of workable thickness and has followed these deposits to sufficient lateral extent to prove fairly well the existence of substantial reserves on this property."

Mar 1, 1948