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By B. E. Davis

Over 80 pct of domestic phosphate rock, which is the starting material for phosphorus-containing fertilizers, comes from central Florida deposits. As K-her grade deposits are depleted, lower grade phosphate ores containing 'Mg0 in the form of dolomite are encountered. Treating high MgO ores with present beneficiation technology will not yield a concentrate meeting specifications for acidulation. The Bureau of Mines conducted research on three high-MgO phosphate samples from south Florida. The sales contained, in percent, 5.4 to 10.2 P205, 1.9 to 7.6 MgO, and 35.3 to 60.1 acid insolubles. A technique of sizing, grinding, desliming, scrubbing, and redesliming was used to produce a feed suitable for continuous flotation studies, A conventional fatty acid-fuel oil rougher flotation followed by two to three cleaner stages resulted in concentrates containing, in percent, 30.7 to 31.3 P205, 0.6 to 1.3 MgO, and 2.5 to 4.8 acid insolubles. The P205 recovery from the flotation feed ranged from 55.1 to 89.7 pct.

Jan 1, 1984

By Jos. R. Guiteras

This paper describes the pumping operations at the Ajax, Cresson, and Vindicator dines in the Cripple Creek mining district of Colorado during the summer of 1936. At that time the three mines wore pumping 6,500 gallons of water per minute into the Roosevelt drainage tunnel. Cripple Creek is the most important gold district in the State; it has yielded gold valued at over $365,000,000. The mines engaged in pumping are among the largest producing properties in the district. ACKNOWLEDGMENTS The author wishes to acknowledge the friendly cooperation of mine officials at the properties visited. At the. Ajax mine information was courteously given by Clayton Kissel, mine superintendent, and his staff; R. Y. Roby contributed the drawings. For information on the Cresson mine, thanks are expressed to Al H. Bebee, mine superintendent, and his staff, especially to Guy Rorabaugh, master mechanic, and to engineer Carlton. At the Vindicator mine, J. S. Anderson; mine superintendent, and Robert Welch, master mechanic, assisted; the latter furnished most of the information about that mine. Acknowledgment is also made of the cooperation of M. H. Salsbury, engineer at the Portland mine, who supplied technical data on the Roosevelt drainage tunnel.

Jan 1, 1937

By Robert H. Merrill

This report summerizes the various studies made to determine the size and support of roofs in the upper shale formation, White Pine Copper Mine, Michigan. These studies were a cooperative effort of the White Pine Copper Company and the Federal Bureau of Mines. Before this investigation, the upper shale formation had been found to contain about 30 to 40 percent of the total mineralization in the ore zones. Investigators estimated that this shale could be economically mined by room-and-pillar methods, provided that the roof would stand over spans of 25 to 32 feet. The problem remained to determine the number of bolts required to safely support these spans. Unbonded fractures in the roof structure of the deposit complicated the use of laboratory methods for determining bolted roof support. Therefore, a method was devised to determine the in-place support which would consider the unbonded fractures. In this method the roofs of 3 rooms with spans of 20, 28, and 36 feet were intentionally overbolted as the rooms were mined. Following stability tests that sometimes exceeded 6 months, the bolts were selectively removed and roof sag, roof strain, and changes in bolt loads were measured concurrently. The number of bolts required for support of these spans was computed from these data.

Jan 1, 1961

By F. W. Wessel

This report summarizes Bureau of Mines laboratory tests of four tungsten¬-bearing materials of various grades, The test work has demonstrated that the dry reaction between sodium carbonate and scheelite is best conducted at 900° C. or a few degrees less. The sodium carbonate requirement, in addition to the stoichiometric equivalent of the scheelite, is in some inverse relationship to the grade of tungsten in the ore. Residence time and particle size exert a definite but minor control on the reaction. Pressure-digestion tests on an impure concentrate indicate the technical feasibility of extraction by this process. INTRDUCTION Over 100 years ago Oxland discovered that tungstic oxide could be removed from wolframite and converted to a soluble form by reacting the mineral with a soluble alkaline salt at elevated temperatures. He patented this discovery, and this patent 4/ since has been the basis for most tungsten extraction. Much literature exists on this process and its modifications, and the characteristics and possibilities of the reaction are quite well defined.

Jan 1, 1956

By Lindsay D. Norman

Four chloride and seven fixed-nitrogen processes for recovering manganese from domestic resources are described. The chloride processes are divided into two classes (leaching and chloridization) depending upon the major operation responsible for converting the manganese minerals to the chloride from which manganese oxide products are obtained. The fixed nitrogen processes, all of which yield high-grade manganese oxide products, are essentially either leaching or roasting processes. The 11 processes include HC1 leach, HC1 chloridization, HC1 chloride volatilization, CaC12 chloride volatilization, NO2 leach, HNO3 leach, HNO3 ?NO2 leach, H3 ?CO2-H2O system leach, (NH4)2SO4 leach, (NH4)2SO4 roast , and ammonium salt roast .

Jan 1, 1963

Provide an inexpensive, simple means of supporting highly yielding ground In underground mines. Approach The Bureau of Mines developed a high capacity support post made from standard steel pipe which, when using a 60-inch post configuration, has a 45-ton capacity and a yield length of 24 inches. How It Works The post mechanism is a three-piece unit consisting of a top and bottom leg (made from standard steel pipe) and a separate foot bracket. During installation in the mine, the bottom leg is placed on a relatively flat surface on the mine floor and the top leg is placed over it until its flared end contacts an expansion ring attached to the bottom leg. As the roof and floor converge, the flared end of the top leg is forced into the expansion ring, causing the walls of the top leg to be deformed radially and along the axis. The mechanism will yield until the unit bottoms out after about 24 inches of yield.

Jan 1, 1987

By Lindsay D. Norman

Four chloride and seven fixed-nitrogen processes for recovering manganese from domestic resources are described. The chloride processes are divided into two classes (leaching and chloridization) depending upon the major operation responsible for converting the manganese minerals to the chloride from which manganese oxide products are obtained. The fixed nitrogen processes, all of which yield high-grade manganese oxide products, are essentially either leaching or roasting processes. The 11 processes include HC1 leach, HC1 chloridization, HC1 chloride volatilization, CaC12 chloride volatilization, NO2 leach, HNO3-NO2 leach, NH3-CO2-H2O system leach, (NH4)2SO4 leach, (NH4)2SO4 roast, and ammonium salt roast.

Jan 1, 1963

By Jr. Sillers

This is the sixth report of investigations in cooperation with the steel industry to establish the technological acceptability of electrolytic manganese in steelmaking processes. The bulk of the .electrolytic manganese used in these tests was produced by the Bureau Of Mines from domestic ores at its Boulder City, Nev., pilot plant by the process developed by the Bureau. Electrolytic manganese for the first series of tests made in 1940 was supplied by the Electro manganese Corp., Knoxville, Tenn. The first report dealt with the application of electrolytic manganese to the manufacture of stainless.steel;9 the second with tests in acid electric and acid open-hearth low and medium carbon-steel castings; the third with its use in rimmed and? killed low-carbon steels; the fourth with its application to the manufacture of stainless steel as well as the Timken 16-25-6 alloy for gas turbines; and the fifth with tests in acid and basic electric steel foundry practice and basic steel ingot production.

Jan 1, 1948

By Howard D. Jacobs

A bulk sample of oxidized taconite taken from the western Mesabi Range was evaluated by the Bureau of Mines using the Bureau-developed selective flocculation-desliming-cationic (or anionic) flotation process. The raw ore sample containing 32.3 pct Fe was treated by both cationic and anionic flotation. Using the cationic system the concentrates averaged. 37.2 wt-pct of the feed and contained 62.8 pct Fe and 4.7 pet Si02 with an iron recovery of 72.3 pet. With the anionic system, concentrates averaged 37.7 wt-pet of the feed and contained 63.0 pct Fe and 5.3 pct 8i02 with an iron recovery of 73.5 pct. A comparison of reagent costs showed that the cationic process cost 144.1 cents per long ton of crude ore and the anionic process 178.7 cents per long ton of crude ore. Reclaimed water comprised 86 pct of the total water requirement for anionic flotation and 88 pct for cationic flotation. The ore used in this study was one of three samples representing about 3.25 billion tons of oxidized taconite containing from 32 to 36 pct feed iron. Previous study had indicated that selective flocculation-desliming-cationic flotation would produce concentrates from the other two samples of 61.7 pct Fe and 5.1 pct Si02 at 67-pct Fe recovery, and 63.5 pct Fe and 4.3 pet Si02 at 8S-pct Fe recovery. By developing a successful treatment for these ores, the Bureau has insured the availability of technology for processing an amount of raw iron ore which, by itself, would supply U.S iron needs for 50 to 75 years at expected consumption rates.

Jan 1, 1981

Objective: The Roof Monitoring Safety System (RMSS) provides a first step in roof behavior awareness. By understanding and measuring roof movement in an underground mine, the potential for injuries or fatalities to mine workers from fall of ground can be lessened. Also, officials at an underground mine with a history of data on roof movement are better prepared to make a decision on remedial actions if falls of ground become a problem. The RMSS provides a safer, simple, and inexpensive means for measuring roof movement.

Aug 1, 1998

By J. P. Powell

Since the beginning of waterflooding in the Midcontinent area, the Bureau of Mines has published many reports3-6/ describing in detail the results obtained on individual waterflooding projects in the area. These are intended as guides for operators in the selection of well-spacing, water-treating, and other techniques, as well as an indication of the results being obtained in waterflooding in various areas, fields, and horizons. In addition, Bureau personnel has arranged a tour of selected waterflooding projects each year for the past several years so that actual operating conditions may be observed and an additional opportunity provided for exchanging information. Each of these tours has been supplemented by a published

Jan 1, 1959

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 J. B. Janus

In connection with the purchase of coal under specifications for Government use, the Bureau of Mines in this report has compiled data on 81 mines located in 15 States. This annual report lists analytical data on the composition and quality of tipple and delivered samples of coal collected during fiscal year 1973. Tipple samples were collected by Bureau of Mines engineers at tipples as coal was being loaded into railroad cars or trucks. Ultimate analyses are given for most of the coalbeds listed. The deliveries were sampled at destination in accordance with instructions issued by the Bureau of Mines. All samples were analyzed in the Bureau laboratory at Pittsburgh.

Jan 1, 1973

By Charles E. Whieldon, C. I. Pierce

Data on the oilfields in Mahoning , Columbiana , Carroll , Jefferson , and Harrison Counties , Ohio , were collected from scattered sources and compiled to make the information readily available to operators who may be interested in conducting secondary - recovery operations in the area . General geology , oil production , oil - productive acreage , core data , reservoir calculations by townships , and miscellaneous data and reference material are presented .

Jan 1, 1965

The following additional studies are recommended: 1. Future development of the magnetic sludge process should involve optimization of the process variables; these include stirring rate, sludge heating time, aeration rate, method of preliminary sludge dewatering, and the effects of magnetic separation for final sludge processing. In addition, the matter of amenability of coal mine waters to treatment should be considered more thoroughly by means of a more comprehensive literature review as well as actual tests on mine drainage samples. 2. The technique of sludge freezing should be explored further. Emphasis should be given to conservation of energy in the process, and the filtration characteristics of the resulting sludges should be evaluated. 3. Further studies should be conducted on the feasibility of the CO2-addition approach to mine drainage sludge densification. The filtration characteristics of product sludges should be evaluated, and the possibility of recovering and recycling the residual alkalinity of the sludge, either directly as CaCO3 or as CaO plus CO2 after calcination, should also be explored further. 4. Efforts should be made to develop cost data for the conceptual processes involving magnetic sludge formation, sludge freezing, and C02 pretreatment, with the purpose of selecting at least one of these processes for further testing at a field site. 5. The use of inexpensive waste materials (e.g. fly ash, "red dog," slag) as sludge additives, possibly in conjunction with coagulant aids, should be considered further. Results of the present studies have indicated that such materials, employed in relatively large amounts, increase the density and enhance the filterability of sludges from lime neutralization of coal mine drainage. The use of pulverized blast furnace slag in this regard appears particularly promising, and studies should be made to ascertain its availability, relative cost, residual alkalinity, and behavior as an additive in conventional mine drainage treatment processes involving lime neutralization and aeration.

Jan 1, 1971

"Contained in this chapter is a listing of the publications and reference books which have come about as a result of respirable dust research performed by faculty, staff and graduate students in the Generic Mineral Technology Center for Respirable Dust at The Pennsylvania State University, West Virginia University, University of Minnesota, Massachusetts Institute of Technology, and Michigan Technological University. These publications have appeared in scientific journals, proceedings of the national and international symposiums, and professional meetings. Complete citations of the publications can be found in Volumes 3 through 6 and Volume 8 of this series. The agenda of the last annual GMTC seminar, held at West Virginia University on February 1 - 2, 1988, follows. The project presentations are organized under the five research areas. All projects currently active were presented to the Advisory Committee. New project submissions were not. The authors were allotted thirteen (13) minutes for their presentations; the remainder of the twenty (20) minutes allotted for each project was used for introductions, transitions, and questioning by the Advisory Committee. Each author used a standard format for presentation of his/her materials for review; handout materials were distributed to the Advisory Committee for reference. Opening remarks were made by Dr. Richard Bajura of West Virginia University and Dean Robert L. Frantz and Dr. Raja V. Ramani of The Pennsylvania State University.The Generic Mineral Technology Center for Respirable Dust is funded by the U.S. Bureau of Mines through the Mining and Mineral Resources Research Institute Program. The opinions and conclusions expressed in these papers are those of the authors alone and do not represent the opinions of the Generic Mineral Technology"

Aug 31, 1989

By J. A. Eisele

The Bureau of Hines conducted a bench-scale investigation of a concentrated H2S04 reaction for recovering and separating rare-earth elements, barium, and strontium from a bastnasite ore and byproduct. Barium and strontium were dissolved in the concentrated acid and precipitated as a mixed product by water dilution. Separation of strontium from barium was effected by reaction with Na2C03 solution, followed by a dilute acid leach of the SrC03 formed. After removing the barium and strontium from bastnäsite are, the rare-earth elements were roasted to water-soluble sulfates. The rare-earth sulfate solution was subsequently processed by solvent extraction to produce rare-earth oxides low in lead and magnesium.

Jan 1, 1974

This publication summarizes the Bureau's activities as part of a study of the Juneau Mining District (JMD) during the period 1984-1988. The objectives of the program were to identify the type, amount, and distribution of mineral deposits in the district, determine ore reserves, study beneficiation technologies for the ore, make feasibility studies, and address economic and legislative effects on mineral development. The JMD study was a cooperative study involving the Bureau and the Alaska Division of Geological and Geophysical Surveys (ADGGS). Over 30 employee-years were spent by the Bureau on this project. Bureau investigations in the JMD consisted of a district-wide investigation of industrial materials in addition to site-specific investigations of precious and base metals in five subareas. During the 4 years of the JMD study, more than 300 areas, mines, prospects, and occurrences were visited, which contain gold, silver, copper, zinc, lead, nickel, cobalt, tungsten, molybdenum, chromium, and platinum group metals (PGM). More than 59,000 feet of underground workings were mapped and sampled. More than 5,500 samples were taken; one diamond drilling program and three geophysical surveys were completed. An up-to-date and complete mineral data base for the JMD did not exist prior to this study. The JMD study, which coincided with a tremendous increase in mineral interest and activity in the district, has proven to be valuable to both the minerals industry and land management agencies. The discovery of two new mineral occurrences and compilation of data on known mines, prospects, and occurrences have aided industry activity in the region. The study enabled timely data to be available to land management agencies at the Federal, State, and municipal levels.

Jan 1, 2012

By Frank E. Cash

The compensation-insurance rates for quarrying in North Carolina are 11 times higher than for the State?s major industry, textiles. Some operators are willing to accept this as representing the ratio of existing hazards. This was not true of the management of the Southern Aggregates Corporation, and in 1935 it tools definite steps to correct the idea of its local officials and employees that loss of life and limb in quarries is inevitable. ACKNOWLEDGMENTS The authors acknowledge gratefully the assistance and information concerning these operations furnished by H. M. Shaw, safety director (also secretary and treasurer), Southern Aggregates Corporation, Raleigh, N. C.; by the following superintendents: J. H. Rodgers, Blair Quarry, Blair, S. C.; J. D. Lane, Greystone and Rolesville Quarries, Henderson, N. C. ; J. H. Arthur, Guilquarry, Stokesdale, N. C.; J. H. Watkins, Rockton Quarry, Wendell, N. C.; P. A. Wellenborne, Reidsville Quarry, Reidsville, N. C.; and J. L. Kirchin, Woodleaf Quarry, Woodleaf, N. C.; by the various foremen at the plants, and by Murry Id. Grier, safety engineer, North Carolina Department of Labor, Asheville, N. C.

Jan 1, 1940

By M. P. Youker

USE OF LOW-PRESSURE GAS BURNERS IN OIL- FIELD BOILERS

Feb 1, 1922