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By Rogers F. Davis

This publication has been prepared to supply manufacturers and industrial users a listing of mobile diesel-powered transportation equipment approved or certified by the Bureau of Mines f r use in gassy noncoal mines and tunnels. Testing of diesel-powered equipment is one phase of the Bureau's health and safety program of approval of electrical and diesel equipment designed to prevent explosions, fires, shocks, and toxic hazards in underground mines. In mines such equipment must be used and maintained properly. Manufacturers submit machinery and component parts to the Bureau for study f their design and safety features. Equipment must pass exacting tests and meet strict requirements established through research, development, and experience before the Bureau approves it as permissible for safe use in mines.

Jan 1, 1967

Develop a means of determining both the fill level of material in an ore pass or bin and the location of bridging material causing a blockage.

Jan 1, 2000

By Albert W. Deurbrouck

The performance of four sand cones was evaluated by the Bureau of Mines in three preparation plants that utilized cones in various flow schemes. The cone at plant A was a simple two-product one that provided clean coal and refuse. Plant B had two cones; one cone made a primary separation and the other a secondary separation. The primary cone separated salable coal from heavy rejects. The secondary cone separated a low-ash metallurgical coal and an intermediate-ash product suitable for plant fuel or steam markets. In plant C the sand cone was equipped with a middlings draw Which continually removed an intermediate specific-gravity product below the surface of the cone. The three primary separations of raw coal effected between floats and sinks were excellent. The recovery efficiencies for the plus 1/4-inch material ranged from 99.8 to 97.6 percent, the error areas ranged from 19 to 23 square centimeters, and the probable errors in specific gravity ranged from 0.033 to 0.024. The performance data of the two secondary separations varied from excellent in plant B, where the separation was on a par with the primary separations, to somewhat inferior in plant C, where the secondary separation was effected at the middlings draw.

Jan 1, 1965

By Patricia R. Devine

This report expands an earlier study by Jack Faucett Associates (OFR #40-88) of the same title. Both reports are based upon an interindustry analysis from 1963 through 1982, during which time U.S. metals consumption and production did not keep pace with economic growth. The report discusses three sources of change: technological change, economic growth, and composition of final demand, as well as the relative importance of the individual components of final demand for metals. The results show investment and personal consumption to be the most metal-intensive components of final demand, and technological change to be the major cause of decline in consumption growth during the study period. Technology change is defined as alterations in production processes resulting in more or less consumption of metal per unit of output, often because of material substitutions and design changes. A trade analysis shows the significance of import growth, particularly indirect imports (metal contained in imported goods) as a factor contributing to the reduced growth rate of domestic metal production. The effect of import growth is partially offset by indirect export growth, suggesting that continued increase of all U.S. exports can have a strong effect in reducing the negative trade balance in metals.

Jan 1, 1988

By E. S. Leaver

Experiments dealing with the dissolution of silver by cyanide from various silver minerals-were reported, several years ago.4/ This work showed that the silver in some silver minerals is completely and readily soluble in cyanide solution, whereas other silver minerals must be given special treatment before or during cyanidation to obtain much dissolution of the silver by cyanide. Flotation as a method for treating silver ores has not been studied much, except in the case of base-metal ores carrying silver, Particularly lead-silver ores. However, many mills now are concentrating gold ores by flotation, and when such ores also contain silver the recovery of the silver by flotation is of considerable importance. Moreover, many mines contain ore in which silver is the principal valuable constituent. Some of these ores are amenable to cyanidation, but the cost of a cyanide plant may be prohibitive because of limited ore bodies or other factors. In such instances the successful application of flotation would mean that the property could be operated.

Jan 1, 1939

By E. S. Leaver

Experiments dealing with the dissolution of silver by cyanide from various silver minerals were reported several yews ago.4/ This work showed that the silver in some silver minerals is completely and readily soluble in cyanide solution, whereas other silver minerals must be given special treatment before or during cyanidation to obtain much dissolution of the silver by cyanide. Flotation as a method for treating silver ores has not been studied much, except in the case of base-metal ores carrying silver, particularly lead-silver ores. However, many mills now are concentrating gold ores by flotation, and when such ores also contain silver the recovery of the silver by flotation is of considerable importance. Moreover, many mines contain ore in which silver is the principal valuable constituent. Some of these ores are amenable to cyanidation, but the cost of a cyanide plant may be prohibitive because of limited ore bodies or other factors. In such instances the successful application of flotation would mean that the property could be operated.

Jan 1, 1939

By Mackenzie Burnett

Quick-Fix Blowout Stoppings were evaluated in several underground mines as an alternative to conventional ventilation control bulkheads. Blowout stoppings offer considerable savings in bulkhead construction and repair costs if the 0.1 inch H20 of differential pressure required to inflate them is available. The Quick-Fix Blowout Stoppings were utilized successfully in uranium mines in the Southwestern United States where savings in bulkhead construction and repairs to blast damaged bulkheads are estimated to equal $9,500 over the projected 2 year average life of a blowout stopping. Two types of material were evaluated. Five methods of anchoring the stoppings to drift walls were evaluated. Three methods of anchor attachment to the stopping material were evaluated. Blast pressure measurements were made in conjunction with the evaluation of the blowout stoppings.

Jan 1, 1978

By Arno C. Fieldner

Coal for coke production is fundamentally necessary for the manufacture of pig iron , and pig iron must be had for making steel - a vital element in our modern industrial economy . In both World Wars , special effort by Government and industry was required to meet the emergency of greatly increased demands . In the first World War , lack of coke - oven capacity , rather than lack of coking coals , was the principal problem ; but in the second World War both oven capacity and coking -coal mining capacity were pushed to the utmost . Because of inadequate supply , it became necessary to allocate a part of the production of these coals from other fuel use to coke production . This was done by the Solid Fuels Administration . These experiences raised a question , during and after the war, as to the nature and amount of the minable reserves of coking coal suitable for the manufacture of metallurgical coke ; and to what extent the lower -rank and lowergrade coals could be utilized by improving preparation and by appropriately blonding different coals . Obviously , much investigation and research are required to find answers to these questions . Somo work was done by Governmental and industrial agencies during the war , and , fortunately , more has been undertaken since the close of It is the purpose of this paper to review briefly our fuel reserves , with special reference to coking coal , and to discuss the problems of utiliz . ing progressively poorer coking coals as the reserves of high - quality coals approach depletion .

Mar 1, 1950

By Fred D. DeVaney

The Mesabi iron district of Minnesota has a potential production of over 50 million tons of iron ore annually. The large shipments of ore each year are gradually depleting the reserves, and if the present rate of production is to be maintained there must be a growth in the present available ore supply. Growth is a natural course. The growth of a city may be affected by the addition of city blocks or by the improvement of utilities necessary for its betterment. These may go on in the order named or concurrently. The city-block type of growth of the Mesabi has been tremendous, and the "betterment" type has followed in due course. Probably the former has reached its limit, and if so, more time will be allotted to the latter. It is not the intent of this paper to present either a eulogy of the wonderful mining methods or a history of the milling, but it is pertinent to say that if the lean-ore area continues to produce, the continuance will be more the result of further improvement of milling methods now well under way than of extension, of boundaries by the city block plan of growth. In an examination of the western end of the Mesabi district one finds sludge basins containing millions of tens of millable ore rejected by washing plants which were built for economy in operating cost and with little thought of conservation, and rich tailings piles of jigging plant rejects. In addition, there is an appreciable tonnage of bowl rake products so low-grade that it requires mixing with the best ore of the district to make it merchantable.

Jan 1, 1932

By Robert H. Mattes

The Lake Lynn Laboratory is a multipurpose mining research laboratory operated by the Bureau of Mines and located in Fairchance, Pa, It consists of both surface and underground facilities. The initial focus of the facility, scheduled for full operation in fall 1982, will be on the problems of fires and explosions in mines. The initial experimental explosion was fired on March 3, 1982. The intent of this document is to provide the reader with detailed information on the physical capabilities of the Lake Lynn Laboratory. Subsequent publications will focus on the capabilities of Lake Lynn as compared with those of other similar facilities worldwide, and a comparison of initial explosion test results realized at Lake Lynn and comparable results from the Bruceton Experimental Mines.

Jan 1, 1983

By A. Wahab Khair

"This paper presents an analysis of fracture mechanisms in coal subjected to bi-axial state of stresses, indentation of laterally confined coal specimen. Coal specimens were loaded to failure by the straight wedge indenters at various lateral confinement pressures. Strain distribution and acoustic emission characteristics of coal specimens under stress were recorded. The influence lines of vertical forces acting on the horizontal straight boundary of the coal specimen for each type of wedge indenter have been established using holographic interferometry technique. The effects of wedge indenter angle, confinement pressure, and coal anisotropy on fracture types, failure modes, and post-failure conditions were studied. The results indicated that combined application of holographic interferometry and acoustic emission monitoring techniques is not only suitable ·for studying deformability of heterogeneous and microscopically discontinuous material under stress but it also enhances the mode of fracture during the post failure stage. INTRODUCTIONOne of the relevant processes in the coal cutting technology is the application of indentation theories. Since most cutting tools in the coal industry are wedge shaped most of the indentation research is found for a wedge shaped tool.A wide range of behavior is found in different rocks subjected to the wedge penetration. A rock which is elastic brittle at standard pressure might become elastic plastic at high confining pressure (Gnirk and Cheatham, 1963). It was also observed that some rocks will merely be crushed and indented by a wedge whereas others will crack and form chips, furthermore the existence or non-existence of chips depends mostly on the geometry of the indenter, type of rock and the depth of penetration (Evans and Murrel, 1958). However, coal cutting technology is mostly explained by models which use rigid wedge to penetrate into a brittle material in which both crushing and chipping will occur (Evans and Murrel, 1958, 1962)."

Jan 1, 1988

By Thomas J. Peters

In 1987, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied a 12,564-acre portion of the 34,795-acre Rockhouse Wilderness Study Area (CA-010-029) in order to evaluate its identified mineral resources. The study area is located in Kern and Tulare Counties, CA, about 60 air mi northeast of Bakersfield at the south end of the Sierra Nevada. A review of the geologic and mining literature, and a field examination identified a turquoise and a gold prospect in the study area, and another gold prospect and a feldspar prospect within a mile of the study area boundary. Thirty-three rock and 16 alluvial samples were taken.

Jan 1, 1988

By Oliver Bowles

The United States has never attained importance as a producer of asbestos, the domestic output being only 1 to 3 percent of the quantity required to supply raw material for its extensive asbestos-product manu- facturing industries. Production is centered in four principal countries-- Canada, Rhodesia, Union of South Africa, and the Soviet Union. Since asbestos first became an important commercial commodity the Province of Quebec, Canada, has led in tonnage produced, but a large proportion of the output of this province is shorter, nonspinning grades. Since 1916 the Union of South Africa and Rhodesia have become increasingly important as sources of the higher-grade spinning fibers. Before the World War Russia ranked next to Canada as a producer of asbestos, but during the revolution- ary period the industry in that country was almost at a standstill. In 1926, however, activity was revived, and each year since then production and exports have increased greatly. Minor quantities of asbestos are produced in Cyprus; Australia, Finland, and several other countries. Chrysotile is the leading product in all the producing countries, but substantial quantities of both blue (crocidolite) and brown (amosite) asbestos also are produced in the Union of South Africa. Minor quantities of anthophyllite and similar amphibole varieties are mined in the United States, Italy, Bulgaria, Finland, and several other countries.

Jun 1, 1934

By H. C. Miller

The success of any project in which gas is injected into oil-producing sands to increase the current rate or the economic ultimate production of oil or in which surplus gas from oil producing operations is stored temporarily in reservoir sands that have been wholly or partly depleted of their producible oil depends mainly upon an understanding of the underground movements of oil, water, and injected gas and the ability to control their speed and direction of migration through the reservoir sands. Many operators believe that injected gas always travels up the structure and drives oil to wells structurally higher than the injection wells, because the specific gravity of the injected gas is less than that of the fluid substances in the formation. Consequently, many injection wells are located on the flanks of oil-bearing structures with the idea of utilizing the energy of the injected gas to drive the oil to producing wells higher on the structure. It is true, under certain conditions of pressure and fluid depletion of the reservoir sands, that injected gas will move in an up-structure direction, but the theory that injected gas always moves up the structure is based on an erroneous conception of the laws that pertain to the expansion of gases. By definition, "a gas is distinguished by its property of infinite expansion and is limited in volume only by the walls of the vessel which contains it."3 The expansion of gas that is injected into reservoir sands also is limited by "walls" that surround the space influenced by the injected gas. The walls of the majority of undrilled or virgin oil-bearing reservoirs in California are the impervious shales overlying and underlying the productive strata and the "dams" or effective barriers of edge water around the rims of the reservoirs. When gas is injected into the sands of a producing reservoir, regardless of the location of the injection well on the structure or the degree of depletion of oil from the sands, one of the walls which confine the gas in the structure about the injection well is fluid. This wall will be edge water in a nearly depleted reservoir, where the drainage cones or regions of reduced pressure about injection and producing wells intersect; and, where there is no interference of drainage cones and the injection well is structurally above the edge water, the wall will be oil. In some producing reservoirs bottom water may be the lower wall of the space that confines the gas about injection wells, but the effect of bottom water on limiting the expansion of gas is the same as if the water was not present and impervious formation separated the producing from the underlying nonproducing strata. Therefore, since compressed gas always seeks regions of reduced pressure and its final volume is limited only by formation and fluid barriers and since the force exerted by the gas under pressure is equal in all directions, the course of migration of injected gas in reservoir sands in California and the

Jan 1, 1932

By E. J. Murphy

"INTRODUCTION This investigation is a continuation of previous work 3/4/5/ on the gaseous products of permissible explosives with and without sheaths. The range of oxygen balance of the explosives has been considerably increased. As has been shown previously, certain approximate relations exist between the volumes of gaseous products and the oxygen balance. Further systematization of the data is not feasible, since the method of theoretioal calculatln of the gaseous product is not yet satisfactorily developed. In a previously described method, 6/ it has been assumed that the explosion occurs at constant volume and that thermodynamic equilibrium is established. Apart from the presumably less important uncertainty of some of the thermodynamic data, it is not known how the confinement of the shots in the Bichel gage or the Crawshaw-Jones gage should be treated, or whether thermodynamic equilibrium is fully attained; nor can the extent to which the equilibrium composition changes during the subsequent period of expansion and cooling be judged with any reliability. Therefore, no calculations have been attempted. However, in anticipation of possible future theoretical interest and as an aid in answering practical problems, the new data are presented in the same minute detail as was done previously."

Mar 1, 1948

By Franklin H. Persse

Domestic bismuth supply was projected from production figures for the ores in which it occurs--copper, lead, zinc, and tungsten. Published and unpublished data concerning host ores were examined to determine bismuth reserves and resources, and mine production. Potential recoverable bismuth occurring with reserves and resources of copper, lead, and zinc was estimated to be 36.3 million pounds. A bismuth availability diagram was developed from quantity estimates and ratios of production cost to value for these host ores. Additional recoverable bismuth occurring with domestic tungsten reserves was estimated to be 1.5 million pounds. Domestic byproduct production of bismuth will approximate 1.3 million pounds annually by 1980. This quantity will provide about 37 percent of the 3.5-million-pound estimated requirement for that year. Known world supply of bismuth appears to be sufficient for world demand to the end of this century. The study indicates that bismuth reserves and potential resources in the rest of the world have not been adequately reported.

Jan 1, 1970

By L. T. MCELVENNY, Robert B. McElwaine, M. Clair Smith

Production of mercury from the cinnabar deposits of the southwestern Arkansas mercury district began in 1931 , reached its peak in 1942 , and ended in 1944. The mines are now idle . Virtually all the cinnabar was obtained from deposits in a belt , about a mile wide , of steeply dipping sandstone beds in the overriding blocks of three thrust faults . The belt was productive for a length of about 27 miles eastward from eastern Howard County, through Pike County, into Clark County . During the early life of the district, Federal agencies watched and recorded its progress as a contributor of a strategic metal, and later, during the war, conducted investigations designed to advance its development . In 1941 , the Bureau of Mines and the U. S. Geological Survey cooperated in investigations on eight mineralized areas in the western part of the district , to wit : Hales mine , U. S. mine , Lulu Bell property, Hopkins Hill , East Gap Ridge , Gap Ridge , Parnell Hill , and Section 17 mine area . U. S. Geological Survey prepared both surface and mine maps and designated the areas to be investigated ; the Bureau did the drilling , trenching, and sampling involved in the investigations . Twelve holes , aggregating 3,539 feet of bore , were diamond drilled on six properties ; 5,309 linear feet of surface trenches were bulldozed in six areas and 19 samples taken from them ; and 86 underground channel samples were cut in two adits on one property . In 1944 , the Bureau of Mines measured mine dumps and calcine dumps in the district in an investigation of their mercury content . Two mine dumps and one calcine dump were sampled . The data pertinent to the work done by the Bureau are included in this report .

Oct 1, 1950

By R. S. Fowkes

The Bureau of Mines constructed a fully automated pilot plant facility to study the hydraulic transportation of solids through a lock hopper feeder system. An equation for the energy requirements to transport coarse solids hydraulically proved applicable to this system. Optimum velocities were obtained for limestone, mine refuse, and bituminous coal. The experimental data, calculations, and graphs show the effect of velocity, specific gravity, and solids concentration on head loss and power requirements. Other data were obtained and evaluated to determine the effect of particle size on head loss. Results also are given for (a) tests using friction reducing polymers; (b) tests using seven test sections of steel alloy pipe to determine their wear characteristics; (c) tests to determine spatial segregation of moving particles; and (d) tests to determine the effect of shape, size, and specific gravity on particle velocity in a horizontal pipeline. The lock hopper feeder system was found practical for continuous hydraulic transportation of the material types and size ranges tested.

Jan 1, 1969

By James C. Barker

Yttrium and rare-earth element. pegmatite dikes are associated with a peralkaline granitic and nephelene syenite complex near Dora Bay on southern Prince of Wales Island. Mineralized dikes were mapped and sampled during USBM investigations in 1987 and 1988. Coarse-grained pegmatite dikes, which emanated as late-stage magmatic fluids from the intrusion, further evolved into vein-dikes and ultimately silica-rich veins. The dikes can be traced up to two miles along a north-south zone. Lithophile elements exhibit a pronounced zonation in vein-dikes and veins that are distal to the Dora Bay complex with increasing values correlating with increasing distance from the complex. The pattern of mineralization suggests very late stage magmatic fluids containing the incompatable lithophile elements were injected into a preexisting north-south fracture zone. REE mineralogy exhibit fine-grained intergrowths of principally thalenite and bastnaesite with lessor monazite and eudialyte. Euxenite contains most of the columbium values and zircon is commonly associated with the dikes. Estimates of inferred and hypothetical resource tonnage range from 1.7 X 1C6 to 8.5 X 106 st for two deposits. Contained RED (including yttrium) averages 0.5 pct and ranges up to 2.0 pct. Deposits are of polymineralic composition and about half of this resource comprises the heavy yttrium subgroup.

Jan 1, 2011

By Gregory B. Beacher

Analyses have been performed on geotechnical properties of copper, uranium and phosphate (gypsum) tailings materials, with the intent of identifying typical measures of variability within and among sites, and of characterizing such variability for use in reliability modeling of tailings embankments. In all, data from approximately 41 sites were analysed. Fairly consistent results were obtained for within site variabilities. However no one probabilistic model was found to be applicable to all sites. The distributional forms for most of the data sets are regular, and tend toward Normality when spatial trends are removed. At many of the sites sufficient in situ data were available to allow estimates of vertical autocorrelation distances and measurement noise. Available data indicate that variability in pore pressures may have a more important effect than strength property variation. A major problem in interpreting available strength property data results from the unknown drainage conditions during testing.

Jan 1, 1983