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By T. I. Weston

This is one of a series of papers being prepared for and published by the United States Bureau of Mines, describing mining and milling methods and costs at crushed-stone plants throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total production costs. It is recognized' tat publication of total production costs might in many instances cause embarrassment to individual producers, as well as to the industry as a whole. However, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no mis-understanding of the scope of the cost tabulations shall ensue. ACKNOWLEDGMENTS The author wishes to acknowledge the assistance-of F. W. Horton, mining engineer, United States Bureau of Mines, in the preparation of this paper.

Jan 1, 1933

This manual provides instructions for installing, operating, and maintaining a protective canopy on the Galis Mfg. Co. face drill. The instructions are based upon an actual installation made in the mine on face drill model 460-S. The parts list and engineering drawings for the protective canopy are included at the end of the manual. And a discussion of some alternative design concepts is also included. The manual can also be used for retrofitting other face drills with similar protective canopies. Skilled mechanics can determine if the instructions herein would be applicable to the other face drills and can determine any necessary modifications if they are not.

Jan 1, 1973

By E. A. Clarke

The vapor-phase section of the Coal Hydrogenation Demonstration Plant at Louisiana, Mo., was operated for the first time in April 1949. The run lasted only 10 days because of time limitation (pending plant dedication in May) and the small amount of charging stock available. The primary purpose of the operation was to break in and determine the operability of the equipment and to supplement the operators' classroom training with actual practice by operating the plant under mild conditions. A secondary aim was to obtain data on the hydrogenation of petroleum oil and lignite tar distillate at approximately 10,000 p.s.i. while making gasoline and Diesel fuel oil. Although the operations were carried out under conditions considerably below those used in the plant design, a great deal of experience and data was obtained. As it is not feasible at this time to conduct further vapor-phase operations on similar stocks, this report has been prepared to present and summarize the data obtained through this operation.

Jan 1, 1950

Roof falls continue to be the greatest single safety hazard faced by underground coal miners. During 1996-99, 44 coal miners lost their lives in rock falls, and nearly 2,400 were injured. In addition, nearly 6,000 noninjury roof collapses were reported. Roof supports are installed to protect the miners, but support system failures contributed to most of these incidents. Reducing the terrible toll taken by ground falls continues to be a major goal of research by the National Institute for Occupational Safety and Health (NIOSH). The purpose of these proceedings is to provide the mining community with a comprehensive survey of coal mine roof supports. Drawing on many years of research undertaken by the NIOSH Pittsburgh and Spokane Research Laboratories, this volume describes what types of support are available, how they work, and when they should be used. The major subjects covered include roof bolts, standing roof supports, cable supports, and longwall shields. Some special topics are also addressed, including an analysis of roof fall accident statistics, techniques for better skin control, material handling considerations, and longwall mining through recovery rooms. This proceedings volume also contains information on several important new technologies, which are described here for the first time: •Guidelines for selecting roof bolt length, pattern, and capacity that were derived from statistical analysis of the roof fall experience at 37 underground mines; •A new design method for longwall tailgate supports; and •A technique for measuring loads developed within cable bolts. The papers in these proceedings were presented at open industry briefings conducted by NIOSH on New Technology for Coal Mine Roof Support. The briefings were held in Norton, VA, Charleston, WV, Evansville, IN, Tuscaloosa, AL, Price, UT, Glenwood Springs, CO, and Washington, PA. The papers were also presented at the Mine Safety and Health Administration (MSHA) Preventative Roof-Rib Outreach Program (PROP) Seminar, which was held at the National Mine Health and Safety Academy near Beckley, WV.

Jan 10, 2000

By Joseph S. Coffman

To determine the availability of manganese for metallurgical purposes from selected world resources, the Bureau of Mines evaluated the potential production of contained manganese in concentrates based on the demonstrated resources of 23 foreign and 8 domestic mines and deposits in 9 market economy countries. All but 2 of the 23 foreign deposits are operating mines; none of the domestic deposits are in operation. The demonstrated resources of the mines and deposits used in this study represent an in situ ore resource of approximately 2.2 billion tons," containing 780 million tons of manganese with a total recoverable production potential of 514 million tons of contained manganese in concentrates. The analyses of mines and deposits in this study indicate that about 213 million tons of the contained manganese (41 pct) is potentially available at a January 1981 constant dollar long-run total cost of up to $1.50 per long ton unit (22.4 lb, or 10.15 kg contained Mn), approximately 428 million tons (83 pet) is potentially available at a cost of about $1.75 or less, and 491 million tons (95 pet) is available at less than $3.30. The remaining 23 million tons, which is potentially available at much higher costs (about $8 to $35 per unit), represents the U.S. deposits. On an annual basis, with a cost range of up to $1.75 per long ton unit, the availability from currently operating mines would last at least 80 years based on 1980 world production data. Total manganese production costs are estimated to comprise mining-8 pet, beneficiation-3 pet, transportation-26 pet, and smelting-63 pet.

Jan 1, 1984

By Ludwig Schmidt

The petroleum industry has recently shown sucks great interest in the evaporation of crude oil and of gasoline, and in the prevention of evaporation losses that almost daily there is being developed and placed on the market equipment designed especially to reduce these losses. Among the recent developments is a new type of tank roof known as the "floating roof," which practically eliminates the vapor space over the surface of the oil, thus removing one of the chief causes of evaporation. There are at the present writing at least two types of floating roofs which, while similar in fundamental principle, differ mainly in the method of making contact with the inside shell of the tank. One type of floating roof is known as a floating tank deck, and has on its circumference flexible metal baskets containing gravel that .rest against the inside shell of the tank. In the other type of floating roof contact with the tank shell is made by the use of movable buffers or shoes. These are attached to the outer ring of the roof and are pressed against the tank shell by means of springs.

Jan 1, 1923

By W. D. Riley

The Bureau of Mines is conducting research on methods for the rapid identification and sorting of mixed scrap metals and alloys so that domestic scrap resources can be fully utilized. One method, spark testing, is the examination of the pattern of sparks that results when a metal or alloy is ground on an abrasive wheel. This technique requires experienced sorters. Bureau researchers have shown that spectrophotometric methods can be used in lieu of the highly skilled sorter. The spectra of a mild steel, an HSLA steel, several stainless steels, and four nickel-base alloys have been measured. Differences in the spectra that are sufficient for identification are apparent.

Jan 1, 1985

By A. E. Raddatz

Previous Bureau of Mines research has shown that tungsten ores containing as little as 40 pct W032-can be processed by a high-temperature molten-salt extraction technique to produce a tungstate-bearing sodium chloride phase with 99 pct W recovery and little impurity contamination. The objective of this work was to demonstrate that the tungstate-bearing sodium chloride phase can be a suitable feed material for preparing am-monium paratungstate (APT) by a modification to the present industrial solvent extraction process. A combined crossflow-count·ercurrent flow solvent extraction technique to extract tungsten is presented. APT produced by this new technique contained 88.6 pct W032-and the following impurities, in percent: Mn02_ 0.0007, Mo02 0.017, P205 <0.010, and Si02 0.012. Implementation of this processing technique would improve tungsten recovery from concentrates and simplify processing operations.

Jan 1, 1988

By J. C. Meeks, C. L. Klingman

An instrument that is sensitive , portable , safe , and low in cost was developed by the Bureau of Mines for detecting helium leaks by comparing the thermal conductivity and flow rate of the atmosphere around the suspected leak against a reference of helium- free air . A vacuum pump pulls the sample gas through a restriction and over thermistor elements , the combined electrical output of which is affected by thermal conductivity and flow rate of the sample gas . Tests showed that the battery - operated Helium Leak Detector was effective and rugged instrument that could be operated safely in explosive atmospheres . The instrument could also detect , but not identify , other gases such as methane , hydrogen , argon , carbon dioxide , and Freon 12 .

Jan 1, 1964

By M. V. HANSEN, Frank PERZ, Edward Thomas, C. H. SEELING

This is the second of a series of information circulars dealing with the control of roof and the prevention of accidents from falls of rock and coal . Their purpose is to focus the attention of the coal-mining industry on the most - common source of fatalities and injuries in mining coal and to disseminate information that may be helpful in combating the roof - fall hazard . Inasmuch as approximately 85 percent of roof - fall accidents occur in the face region , the importance of analyzing the accident - producing aspects of methods of roof support at the face or lack of method overemphasized . - - cannot be This circular is not intended to be an exhaustive treatise on methods of roof support in face regions but rather is a description of several methods of support that appear to offer distinct advantages with respect to safety and efficient operation .

May 1, 1948

By A. C. Fieldner, W. A. Selvig

Information concerning the fusibility of coal ash has become of considerable value to the consumer of coal, mainly in connection with the troublesome formation of clinker resulting from the melting of the ash constituents of the burning coal. The growing interest in such data has led the Bureau of Mines to make a general survey of the "fusing" or "softening" temperatures of the ash from coals of the United States. It is hoped that this information when used together with the large number of coal analyses published 1 by the bureau will assist the consumer of coal in comparing different coals, and in selecting the coal best adapted for his purpose.

Jan 1, 1922

By Dennis R. Dolinar

The danger to personnel, equipment, and pillar structure created by the spalling of a coal rib can be minimized by installing rib bolts. To assure that a configured support system will maintain a coal rib, the U.S. Bureau of Mines developed a rib bolt system based on a nonpreventable failure concept. A statistical equation quantitatively relates the amount of rib retained to the bolt spacing and the width of the spalled material. Laboratory test results show that the equation accurately predicts the amount of material retained and confirm the validity of the support concept. The examination of rib bolting at a coal mine experiencing rib sloughage provides evidence that the effectiveness of the support can be related to the failure pattern of the spalled material. An analysis of roof and roof support reaction to rib sloughage at the mine indicated that the rib sloughage had little effect on roof stability. Although supporting ribs might not affect roof stability, laboratory test results indicate that the material retained by the support can sustain a load up to 20 pct of the intact compressive strength of the material.

Jan 1, 2010

By H. S. Martin

This paper, describing the concentrating practices at the plants of the Utah Copper Co., is one of a series being prepared by the United States Bureau of Mines in which the data are given in as nearly uniform c manner as possible. The Magna mill is 19 miles west of Salt Lake City on the routes of the Lincoln and Victory highways, and the Arthur plant is 1 mile west of the Magna mill. Both are on the main road west of the town of Magna and east of the town of Garfield.

Jan 1, 1931

By W. J. Kroll

This report on the bibliography of zirconium has been confined to those publications and patents that appear to be useful in the commercial development of the metal, both the malleable and the nonmalleable. The methods of production have been stressed and special attention has been given to the alloys. Compounds of importance, like the oxide and chloride, for the manufacture of the metal or of the alloys have been considered. The use of the oxide in refractories anal in the glass and porcelain industries has been omitted. The present survey is critical; that is to say, an attempt has been made to evaluate the effectiveness of suggestions made in the literature. The exhaustive work of Marden and Richy, Bureau of Mines Bulletin 186, published in 1921, has been taken as a base to start from with the intention of bringing the subject up to date with material published in the last 24 years. During this time there was considerable &apos;advance in the preparation of the metal and Its alloys, and in the development of new uses. On the other hand, there was little progress in the methods of decomposing the ores, so that the chapter on this latter phase is necessarily short.

Jan 1, 1946

By Richard E. Ray, George N. Aul, Fred Garcia, William P. Diamond

Increasing longwall panel dimensions, particularly face width in gassy coalbeds, may result in unexpected increases in methane emissions. To investigate this problem, continuous longwall face emission monitoring studies were conducted at two adjacent mines operating in the Pocahontas No. 3 Coalbed, where longwall faces were to be extended from 229 to 305 m (750 to 1,000 ft). It was predicted by regression analysis of methane emissions data from 229 m (750 ft) wide longwall faces that extending faces to 305 m (1,000 ft) would increase methane emission rates by only 7 percent (0.6 m3/min (20 cfm)), to 8.6 m3/min (304 cfm) at the VP-1 Mine. In contrast, it was predicted that extending faces at the VP-3 Mine could increase methane emissions by as much as 13 percent (1.8 m3/min (65 cfm)) to 16.1 m3/min (567 cfm). The geologic and mine design factors influencing the variation in face emissions between the two mines will be discussed.

By FREDERICK L. WARD

This paper , describing the operation of the Ward Sand and Gravel Co.'s plant at Oxford , Mich . , is one of a series being prepared for and published by the United States Bureau of Mines on methods and costs of mining and preparing sand and gravel throughout the United States . These papers are designed to disseminate technical information regarding the methods used . The cost tabulations represent local operating expenditures only and not total production costs . It is recognized that publication of total costs might in some instances cause embarrassment to individual producers as well as to the industry as a whole . On the other hand , operating costs are essential to the technical discussion and study of the methods employed . The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue . The plant described is a dredging operation with many unique features ; especially noteworthy are the mining of the sand and gravel with hydraulic jets operating on the principle of a water ejector , the unusual construction of the dredge and the self- unloading barges that tend it , the transportation of the sand and gravel to shore in barges instead of in pipe lines , the large storage capacity of the plant , and the fact that all material goes into storage before being shipped .

Jan 1, 1932

By Ann G. Kim, Thomas R. Justin, John F. Miller

The U.S. Bureau of Mines applied its mine fire diagnostic method to an abandoned anthracite mine fire site in Carbondale, Lackawanna County, PA. The technique to locate fires in abandoned coal mines and coal refuse piles includes the determination of hydrocarbon concentrations in mine gases, the imposition of an underground gas flow direction, and use of a surface mapping method, to define heated and cold zones in underground coal strata. The heated zones at Carbondale were characterized by elevated methane concentrations. The results of 25 communication tests were analyzed to define 2 large (approximately 100 by 250 ft) and 5 small, isolated heated zones. An approximate correlation existed between the location of the heated zones and areas of anomalous snow melt. The correlation between the results of the diagnostic test and subsurface temperatures was not significant.

Jan 1, 1992

By Frank G. Miller

Controlling natural-water drives to effect efficient and economic production of petroleum, through wells, from reservoir sands and rocks is a problem of major importance in the oil-producing industry. Water-drive fields are characterized by large quantities of mobile water under high pressure immediately below the oil in the flanks or extraneous parts of reservoir formations, Hence, the water, which is in fluid connection with the oil and a source of a large proportion of the energy available for moving it, advances up-structure to replace it. This phenomenon of water moving crestward into the oil-bearing parts of the reservoir and replacing oil is termed edgewater encroachment. The mechanism by which oil is flushed out and continually replaced by water as the hydocarbon content of the field is depleted must be understood if natural-water drives arc to be used successfully to, induce efficient recovery of oil from its reservoir rocks. Until recently, the function of water in the production of oil has been somewhat obscure and was not given the consideration it deserved in early petroleum production-research programs because of the greater importance associated with and the effort devoted to investigations concerning the relations of natural gas to production of oil. Thus, with virtually no fundamental information at hand, it is not surprising that at first edgewater was considered a necessary evil, and the manner in which it was dealt with depended largely on the experience of the operators. During the intervening years, however, practical information on encroachment of edgewater in oil sands has been widely disseminated as a result of studies of oil-field depletion, and many theories pertaining to petroleum-reservoir energy and performance have been advanced; these theories necessarily included consideration of edgewater as an integral -art of the reservoir fluids and a source of energy for propelling hydrocarbon fluids through the reservoir and to the surface of the ground.

Jan 1, 1941

By Frank G. Miller

Controlling natural-water drives to effect efficient and economic production of petroleum, through wells, from reservoir sands and rocks is a problem of major importance in the oil-producing industry. Water-drive fields are characterized by large quantities of mobile water under high pressure immediately below the oil in the flanks or extraneous parts of reservoir formations. Hence, the water, which is in fluid connection with the oil and a source of a large proportion of the energy available for moving it, advances up-structure to replace it. This phenomenon of water moving crestward into the oil-bearing parts of the reservoir and replacing oil is termed edgewater encroachment. The mechanism by which oil is flushed out and continually replaced by water as the hydrocarbon content of the field is depleted must be understood if natural-water drives arc to be used successfully to, induce efficient recovery of oil from its reservoir rocks. Until recently, the function of water in the production of oil has been somewhat obscure and was not given the consideration it deserved in early petroleum production-research programs because of the greater importance associated with and the effort devoted to investigations concerning the relations of natural gas to production of oil. Thus, with virtually no fundamental information at hand, it is not surprising that at first edgewater was considered a necessary evil, and the manner in which it was dealt with depended largely on the experience of the operators. During the intervening years, however, .practical information on encroachment of edgewater in oil sands has been widely disseminated as a result of studies of oil-field depletion, and many theories pertaining to petroleum-reservoir energy and performance have been advanced; these theories necessarily included consideration of edgewater as an integral part of the reservoir fluids and a source of energy for propelling hydrocarbon fluids through the reservoir and to the surface of the ground.

Jan 1, 1941

By R. W. Stahl

Coal mining has been revolutionized by the continuous miner. This machine has replaced, or has combined into 1, 3 former operations: Cutting, blasting, and loading. During the 25-year period before this machine was introduced, advances had been made in transportation, but the actual "coal getting" remained virtually the same. As frequently occurs, the multiple-purpose continuous miner introduced a new hazard--more rapid liberation of methane. The coal output formerly obtained from 10 to 20 working places might now be obtained from 1. It is true that circulation of air was generally increased; but the bulk of this machine virtually precludes continuous flow of air across the face, where gas may accumulate. Apprehension about this possible hazard led the Bureau of Mines to test face atmospheres during operation; and Report of Investigations 5288, Methane Buildup During Cutting and Continuous Mining Operations (published in 1956), presents proof that real danger may be present in many otherwise well ventilated mines.

Jan 1, 1958