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By D. R. Tesarik

Displacement and stress changes in cemented backfill and ore pillars at the Buick Mine, near Boss, MO, were monitored by engineers from the U.S. Bureau of Mines and The Doe Run Co., St Louis, MO. A test area in this room-and-pillar mine was backfilled to provide support when remnant ore pillars were mined. Objectives of this research were to evaluate the effect of backfill on mine stability, observe backfill conditions during pillar removal, and calibrate a numeric model to be used to design other areas of the mine. Relative vertical displacements in the backfill were measured with embedment strain gauges and vertical extensometers. Other types of instruments used were earth pressure cells (to identify loading trends in the backfill), borehole extensometers (to measure relative displacement changes in the mine roof and support pillars), and biaxial stressmeters (to measure stress changes in several support pillars and abutments). Two-and three-dimensional numeric codes were used to model the study area. With information from these codes and the installed instruments, two failed pillars were identified and rock mass properties were estimated.

Jan 1, 2010

By D. T. Holmes, W. G. Sandell

"INTRODUCTION Three representative lots of ore wore obtained from the Aguila minim district in Arizona during the Bureau's exploration of manganese deposits there. Since only selectively mined ore from this district will meet commercial-grade specifications, the ores were studied to determine their amenability to concentration.Although the purpose of the investigation was to determine the possibilities of the district as a source of commercial-grade manganese, testing was sufficiently comprehensive to indicate the response of the ores to several different types of treatment. Many data of secondary importance have been omitted, end only the more pertinent tests are presented in detail.At the beginning of the investigation of manganese-ore beneficiation in December 1940, the only product marketable to. Metals Reserve Company was ferro-grade manganese, grade B, the requirements for which follow: Mn, min., 48 percent; Fe, max., 7 percent; Si02, max., 10 percent; P, max., O.18 percent; Al12O3, max., 6 percent; Zn, max., 1 percent.Later the specifications were modified gradually. As of May 15, 1943, manganese products were acceptable if they contained over 35 percent manganese and less than 3 percent zinc and 1 percent phosphorus. Prices were based upon material containing 48 percent manganese, 6.O percent iron, and. 11 percent silica plus alumina. Premiums were paid for manganese con¬tent over 48 percent and iron content under 6 percent, penalties being imposed upon products containing loss than 48 percent manganese or more than 6 percent iron or more than U. percent. silica plus alumina.. The specifications for commercial manganese further required that the maximum particle size be 12 inches and that 75 percent of the product be coarser than 20-mesh. Therefore, fine material, such as table and flotation concentrates, had to be nodulized or sintered. In addition, carbonate manganese ores were not acceptable unless calcined.."

Aug 1, 1948

By T. M. Garland

This report presents a more extensive perspective of the calculated profitability of developing and producing crude oil and associated natural gas by primary methods from selected onshore areas of the United States. Estimates were made for cost of drilling, completing, equipping, and producing oil wells at four depths in seven onshore producing areas. A computer program was developed for calculating the discounted cash flow rate of return for the 64 different models in each area resulting from varying the oil-producing rate and production decline rate. The results of these calculations provide data that vividly illustrate the change in rate of return to changes in well depth, initial producing rate, and production decline rate, as well as to variations in development cost and operating expense. Cost per barrel of oil produced in terms of annual cost and total cost is also discussed. Included in the report are explanations of the method of determining costs and the procedure used for profitability analysis. Summaries of all cost estimates and results of profitability analyses are presented in the appendix in tabular form for each of the seven producing areas.

Jan 1, 1972

By John P. Powell

The increasing demands for petroleum and its products and the steadily increasing cost of discovering and developing new oil fields are factors that emphasize the importance of increasing the recovery of oil from known petroleum reserves. Water flooding is a valuable conservation measure, not only preventing premature abandonment of stripper leases but also reviving interest in many areas previously abandoned. The use of water flooding as a means for recovering additional oil from partly depleted oil-bearing formations was first tried in Oklahoma in 1931. Early water-flooding operations were confined to the area of shallow Bartlesville-sand formations in Nowata and Rogers Counties, where many of the projects were outstandingly successful. The results of these operations stimulated activities in other pools in Oklahoma, and by the end of 1949 water flooding had been tried in 25 of the 49 oil-producing counties in the State (fig. 1). Approximately 33 million barrels of oil, or 1,806 barrels per acre, had been recovered by December 31, 1949, from 18,221 productive acres included in the 162 active and abandoned projects in Oklahoma by injection of approximately 449 million barrels of water.

Jan 1, 1952

By Bernard Porter

The densities of LiF, NaF, and KF, of binary mixtures of these alkali fluorides, and of binary mixtures of UF4, ThF4, YF3, LaF3, and CeF with each of tie alkali fluorides were measured as functions of the melt composition and temperature. Molar volumes at 1,000° C were calculated for all the mixtures. Binary systems containing LiF exhibited molar volume ideality. Binary fluoride systems containing either NaF or KF as the alkali fluoride exhibit positive deviations from molar volume additivity. However, molar volumes in the NaF-KF system are ideal.

Jan 1, 1966

By Millard M. Gilkey

This Bureau of Mines report presents results of a detailed study of water usage in the Wyoming mineral industry along with projections for the future In 1964, the mineral industries of Wyoming used 20 billion gallons of new water, nearly all self-supplied, and reused 72 billion gallons, a total usage of 92 billion gallons. Consumption amounted to 2.8 billion gallons. About one-half of the 20 billion gallons of new water was obtained from [srface] sources and the rest from ground water. Reported costs, covering power and maintenance, for the self-supplied new water at mineral industry operations ranged from less than 1 cent to 20 cents per thousand gallons and aver-aged 8 cents. At one mineral-related operation, water was hauled by truck to supplement a well supply. The cost was $2.00 per thousand gallons delivered. However, the supplemental requirement was only 10 gpm. Cost figures for the recirculation of water, covering power and maintenance, averaged 2 cents. In terms of water usage, the value of product for the entire industry was $25 per thousand gallons of new water intake and about $180 per thousand gallons consumed. The study revealed that Wyoming has a water deficiency but that the shortage is less severe than in the arid Southwest. Projection of the water needs of the Wyoming mineral industries indicates that the demand for new water will increase from the 20 billion gallons used in 1964 to 25 billion gallons in 1980, a 25-percent increase. The projected new-water requirement for the year 2000 is 40 billion gallons, a 100-percent increase compared with the 1964 figure.

Jan 1, 1967

By S. J. Gasior

Pilot plant studies showed the technical feasibility of fluidized-bed operation for producing hydrogen and synthesis gas by the steam-iron process. A mixture of iron and iron oxide from 20-to 100-mesh was partially reduced with a simulated producer gas and then oxidized with steam and/or carbon dioxide. Results of tests show the effects of pressure, temperature, bed height, gas-to-solids ratio, type of iron oxide, and composition of gas on the gas and solids conversions during reduction and oxidation. A baffled free-fall solids system was also found operable. The short residence time of about 5 seconds limited conversion of the solids.

Jan 1, 1961

By A. F. Colombo

The western Mesabi range nonmagnetic taconites containing about 34 percent Fe were evaluated by the Bureau of Mines in a 900-pound-per-hour pilot plant employing a selective flocculation-desliming-cationic flotation technique. The flotation step was a reverse flotation process and involved the flotation of the gangue minerals. The objective of the research was to increase the availability of domestic raw materials for the iron and steel industry. The beneficiated ores yielded concentrates containing 62 to 64 percent Fe and less than 5.5 percent Si02 with accompanying iron recoveries that averaged about 75 percent. Comparable flotation results were obtained with either fresh or 80 to 90 percent reclaimed water. Recycled waters having turbidities as high as 5,000 ppm Si02 did not affect the flotation process. Reclaimed waters containing residual calcium contents of less than 10 ppm gave better flotation concentrates than those containing 15 ppm.

Jan 1, 1976

By R. J. Leary

Significant improvements in surface conditions or mechanical properties of steels have been attributed by several investigators to ladle additions of small quantities of rare-earth metals or their oxides. To investigate systematically these effects in wrought and in cast plain carbon and alloy mechanical steels containing approximately 0.35 percent carbon, heats of four representative compositions were melted by the Bureau of Mines in a 4-ton open-hearth furnace. Each heat was cast into three sets of ingots to exemplify respectively, treatments with (1) rare-earth metals, (2) rare-earth metal oxides, and (3) an untreated set as a control. The development of melting, casting and rolling practices is described and discussed. Lance injection of oxygen shortly after melt raised the temperature of the metal immediately as much as 500° F., principally because mechanical agitation exposed the high-carbon metal to the flame and furnace root. An exceptional degree of superheat in the metal at the termination of the refining period was attributed to oxygen injection during the refining period. Bath temperatures higher than industrial practice were permitted by the all-basic furnace lining. Rates of carbon elimination as high as 0.036 percent carbon per minute were achieved by oxygen injections.

Jan 1, 1961

By B. W. Gandrud

In 1927 Coghill showed that there is considerable liberation of the iron oxide mineral from gangue when the Alabama red iron ores are ground to a size suitable for classification and tabling but that there is not sufficient to make possible a high extraction and a high grade of concentrate. Coghill states: High extraction and 'high grade of concentrate cannot be obtained without grinding to a size comparable with flotation or cyanide practice. If grade of concentrate be sacrificed the grinding need not be so severe. These ores slime readily during grinding, and in most instances the slimes are only slightly higher grade than the original ore. Not only do they carry a considerable percentage of the total iron in the ore, so that to reject them as tailings would result in prohibitively low extraction, but they are too fine to be amenable to ordinary methods of gravity concentration. In 1929 the Bureau of Mines published results showing that certain Alabama oolitic iron ores could be concentrated by classification and tabling after grinding, with rubber-covered rods. This selective grinding produced slimes of much higher grade than the original ore, and they were considered part of the final concentrate.

Jan 1, 1934

By A. L. Peyton

Manganese-oxide minerals occur in irregular pockets distributed through the residual clays of the Cartersville district, which lies 45 miles north-west of Atlanta in Bartow County, Ga. The district produces, or has produced, limonite, barite, specular hematite, ochre, ferruginous manganese, manganiferous iron are, as well as manganese. Bureau of Mines engineers have visited the district on three occasions - in December 1939, February 1941, and October 1942. During the visit of February 1941, 80 tons of samples of manganese-bearing clays were taken from seven properties for ore-dressing tests, which were conducted at the Bureau of Mines laboratory at Rolla, Mo. The. October 1942 visit was for the purpose of reappraising the district in the light of knowledge gained from the ore-dressing studies and to prepare a plan for the district's development. Exploratory drilling was begun in March l943 and was continued until June 1945. Nine properties were explored that, roughly follow a line beginning near Cartersville and extend to a point 2 miles northeast of the village of White. The work consisted of bulldozer trenching, rotary bucket churn drilling, sampling, and analytical determinations. The manganese district is 18 miles long with a maximum width of 7 miles at Cartersville, which lies at the center of the district. The work of the Bureau was confined to the northern half of the district between Cartersville and Pine Log. The properties explored comprise but a small portion of the Potential producing area.

Jan 1, 1949

By E. P. Youngman

The basic mining law of Esthonia is the law that was passed by the Parliament (Riigikogu), or State Assembly, on March 17, 1927 (effective Avril 1, 1927), superseding the Russian Mining Law Book VII of the Code) issued in 1912. References in this digest are only to articles of the Law of Merch 17, 1927. However, the law concerning all industrial enterprises (Riigi Teataja No. 28, 1920, Law No. 106) governs not only mills and refineries but also mining operations themselves (arts. 2 and 3). No access was ad to that law. Esthonia is not well supplied with minerals; its industries are primari- ly agriculture and dairy farming. Natural gas, prites, lead, zinc, iron ore, salt, and mineral waters have been found but never as yet in deposits of commer cial size. The production of oil shale is of some importance; and peat, which covers as much as 5 per cent of the total area of the country, is mined in sub- stantial quantities. Cement rock, gypsum, fire clay, and phosphate rock likewise are produced, though only on a small scale.

May 1, 1930

By Will H. Coghill, I. L. Feld, G. D. Coe

The object of this paper . is to make known the superior classification accomplished in a hydraulic classifier designed to make use of principles determined by recent research ... The details of the design , the results of preliminary research , and the final testing are given . The classifier of the new design shown in figure 1 and another one like it are in operation as concentration classifiers in a Birmingham iron- ore mill recovering 4 tons per hour of concentrates from table middling that ` otherwise would require regrinding and retabling . The four factors that contribute to the successful operation of these classifiers are ( 1 ) a teeter column of small diameter , ( 2 ) use of an open - bottom tooter column classifier with a periodic pincer instead of the usual type , which terminates in a vortex, ( 3 ) a sorting chamber under separate hydraulic control , and ( 4 ) a teeter column of more than the usual depth . · At the outset it must be stated positively what the authors mean by hydraulic classification : They mean the reconstruction of a multimineral ground product into fractions graded with respect to size , so that cach fraction has the heavy mineral segregated in the fine sizes and the light mineral segregated in the coarse sizes . This definition presupposes that in multiplespigot classification the low specific gravity minerals are carried beyond the first cells to the later ones . The reader must take into account that , from the standpoint of classification , " ores " may be divided into two types , represented - by the following : ( 1 ) Joplin flint - blende ores , which , because of the hardness of the flint and the softness of the blonde , yield upon comminution a product that already has the essence of classification ; and ( 2 ) Birmingham Big Seam iron oros , which contain " easily shelled - out " sca sand and , upon reduction to about 10 mesh , yield a heterogeneous mixture in which the size analyses of the respective " floats " and " sinks " arc almost identical .

Dec 1, 1945

By Robert J. Evans

The Bureau of Mines is sponsoring a variety of long-term, high-risk research to advance state-of-the-art technology in U.S. underground coal mining. This report reviews the status of many Bureau projects that support fundamental underground coal mining operations; the project areas include cutting coal from the solid (extraction), hauling coal from the face (transport), and activities that sustain daily operations (logistics). Innovative equipment and technology have been developed, with these major objectives: to significantly improve coal mine productivity, to further advance coal recovery and personal safety within the mining industry, and to reduce the time needed to develop longwall panels. The majority of the prototype equipment covered in this report either has undergone or will undergo comprehensive evaluation at Bureau surface test facilities so that performance and reliability can be improved before the equipment is tested and evaluated in a working section underground.

Jan 1, 1988

By Arthur E. Bruszak, Marcel Vanpée

In many practical combustion systems ignition may occur through contact with hot burned gases . Such a process plays a vital role in flame stabilization on bluff bodies . It is also of importance in the ignition of firedamp by the hot spent gases of explosives used in mines . Also , in the communication of flames through narrow channels , a problem of practical importance in flameproofing electrical equipment , the propagation of the flame is essentially a reignition process in which hot burned gases are the agent of ignition . In the actual ignition problem a great variety of conditions may be visualized . Ignition may occur where pockets of hot gases are surrounded by cold explosive mixtures or where pockets of cold mixture may be surrounded by hot gases . Alternately , a flowing stream of combustible mixture may be initially in contact with another stream of hot combustion products , or a jet of hot gases may flow into a cold quiescent mixture ; the jet may be laminar or turbulent , continuous or discontinuous . The hot gas may also consist of the oxidant ( air for instance ) and the cold combustible pure fuel . This study by the Bureau of Mines is concerned only with ignition produced by a continuous jet of gas ( hot ) flowing into a practically quiescent cold mix- The investigation of ignition by bursts of hot gases or by turbulent jets is outside the scope of this report , and work performed on this phase of the problem has been published elsewhere

Jan 1, 1963

By K. E. Tame

The Bureau of Mines is studying possible modifications in conventional ore-processing methods that will confine and permit controlled disposal of radioactive liquid wastes. Stream and ground water pollution from radio-active nuclides, principally radium 226 and thorium 230, in liquid wastes from uranium mills can be minimized by reusing the waste solution within the mill. Such reuse of waste solution in an acid leach-resin-in-pulp flowsheet was investigated in the laboratory. The process consists of acid leaching for dissolution of the uranium, sand-slime separation and countercurrent decantation washing for recovery of a pregnant slime slurry, and the use of ion-exchange resin for recovery of uranium from the slurry. Reuse of clarified barren effluent for washing in the simulated mill circuit was carried through 55 cycles. Dissolution of uranium from the ore averaged 97.5 percent. Washing efficiency of 99.9 percent was attained when using 4.35 volume tons4 of combined barren effluent and makeup water per ton of ore. Absorption of uranium from the pregnant slime slurry by an ion-exchange resin averaged over 99.9 percent.

Jan 1, 1962

By R. V. Ramani

This volume is the second of a four-volume final report on research carried out under a contract from the U.S. Bureau of Mines on the development of a computer simulation model for surface mine reclamation planning. The other volumes are titled as follows: Volume I: Ore Reserve Estimation, Volume III: Mine Coordinate Generator System, and Volume IV: User's Manual for OPMHS/2. The dragline model described in this report simulates the movement of the dragline bucket across the digging face, the swing load, the dump, and swing back. It is programmed to handle chopdown, key cut, main cut, and rehandling operations. Provisions have been made for simulating equipment and mining delays. Any mining method can be specified in terms of numbered blocks, the dragline positions for the mining block and the dumping location for the block. Accounting procedures permit the calculation of production rates, rehandle volume, dig and delay times. The model can be used to study the effects of varying mining conditions, cut width, and spoiling sequence with special reference to toxic spoil, overburden and bench removal procedures. The basic input data for the model include machine parameters, the geology and material characteristics, the mining parameter, and the delay characteristics of the equipment.

Jan 1, 1985

By Hewitt Wilson

A review is given of the nomenclature, sources, imports, statistics, common methods of preparation, and testing of mineral pigments. A description of the Deer Park-Spokane colored-clay district and the laboratory methods of preparation of these colored clays, others, and siennas follows. The mineral pigments were prepared by washing or grinding the original material as received and by calcination of the yellow ocher and brown sienna with and without manganese dioxide to produce red, brown, and black colors. These prepared powders were tested for fineness, oil absorption, and color as compared with well-known brands of commercial pigments. Similar tests were made with several basalt red clays occurring in the neighborhood of Salem, Oreg., and Kalama, Eatonville, and Clay City, Wash. The color particularly was studied, since this property is the most important commercial characteristic of the minerals. PURPOSE OF INVESTIGATION Since the development of the clay industry in the Pacific Northwest, some curiosity and interest have been aroused by the red and yellow clay or ocherouslike material that has often been found associated with the commercial clay deposits. These include the red and yellow "paint pots" near Deer Park and Spokane in eastern Washington, a red clay at Clay City, another close to Eatonville in western Washington, and red basalt earths near Salem, Oreg., and along the Columbia River near Kalama, Wash. Several companies have been organized to produce pigment colors from two of these deposits but have either discontinued or never started operations.

Jan 1, 1929

By Henry C. Meeves

The nonpegmatitic sources of beryllium in Arizona, Colorado, New Mexico, Utah, and four adjacent states investigated by the Bureau of Mines are described. The investigations included 155 properties from which over 6,200 rock samples were collected; more than 5,500 samples were analyzed by the nuclear beryllium-detection technique. Twenty-four of the properties examined had rock containing more than 0.10 percent BeO. Many of the beryllium determinations were made in the field with portable detection instruments by direct scanning of outcrops and by testing samples of rock brought to the instrument. The large domestic resources of low-grade nonpegmatitic beryllium ore in Utah, which were discovered by private enterprise and which respond favorably to small-scale treatment processes, may come into commercial use and thus reduce the dependence of the United States on imported beryl.

Jan 1, 1966

By J. J. Pfeiffer, J. W. Myers, A. A. Orning

A study was made of the feasibility of using washery refuse in the manufacture of lightweight aggregate for building materials . Preliminary caking and burning tests showed that the refuse could be converted into lightweight aggregate but that refuse passing a No. 14 U.S. Standard screen could not be used without additional processing . The aggregate was prepared by pelletizing the refuse and burning out the carbonaceous material on a chain- grate in a refractory - lined furnace . A small stationary - grate furnace was used to study the process variables involved and establish optimum ignition and combustion conditions . Maximum ignition rates were obtained at air rates of approximately 200 lb per sq ft hr , but air rates of 450 or higher were required in the burnout period to obtain temperatures high enough to sinter the ash . The data obtained from this unit were used as a guide in the operation of the chain- grate furnace . In the chain - grate furnace , satisfactory results were obtained by using primary air rates of 200 lb per sq ft hr in the ignition zone and 500 lb per sq ft hr in the burnout zone . The ignition- zone air was preheated to 500 ° F , but the air for burnout was not preheated . A total of 2-1/2 tons of aggregate was prepared in this unit and made into experimental block . A commercial development based upon the results of this study yielded a product which met the ASTM specifications C 130-42 for lightweight aggregate , and blocks made from the aggregate were of good color , durable , and light - inweight .

Jan 1, 1964