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By G. E. McElroy

Changes in existing airway and fan-installation conditions offer the most common opportunities for effecting economical operation of mine ventilating systems, but the largest possibilities for securing this result lie in the original design of the main airways for efficient service. Formulas, and. charts for their graphical solution, are presented herewith for the determination of the elements of airways design when the conditions of service are known, or may be roughly approximated. Although the analyses are made with particular reference to metal-mine airways, there is no essential difference between metal and coal mine main airways, and the methods presented are equally applicable to both. Little attention is paid to designing airways for maximum economy in the ventilation of metal mines. Most of the openings used as main airways are originally designed and used for transportation and other operating purposes. Even where openings are made primarily for ventilation, the possibility of their future use for other operating purposes, or even custom alone, usually results in the selection of a size and shape similar to those of existing openings. Natural conditions, such as heavy ground, often seriously limit the size of opening that can be maintained without excessive expense; and various operating factors, such as velocity limitations on traveling roads, often dictate size requirements in excess of those required for economy in ventilation only. In metal mines the main airways are, as a rule, too small rather than too large for economic service, with the general result that the quantities in circulation are often less than the mine's proper requirements over long periods, even though excessive amounts of power are applied in an effort to remedy conditions.

Jan 1, 1932

By William Cochran

The Bureau of Mines investigated mine subsidence caused by recent underground mining, estimated the extent of damages, and formulated a procedure for evaluating subsidence costs. On the basis of the quantity of material removed from beneath the surface, bituminous coal mining currently causes more extensive subsidence problems than mining of other minerals; costs are highest in areas such as western Pennsylvania where urban and suburban development and related types of land use conflict with mineral recovery. The Bureau of Mines estimated subsidence costs, including surface damages and control costs, for a 12-county area in western Pennsylvania for 1968. Total surface damages attributable to the underground production of bituminous coal in the 1-year period were $295,000; in addition, 12.4 million tons of coal, valued at $4.3 million, was left in place to minimize potential surface damage. Of the total subsidence cost ($4.6 million), $2.7 million was classified as external or social costs, not reflected in the market value of bituminous coal; this averaged $0.05 per ton of production, or slightly less than 1 percent of the market value.

Jan 1, 1971

By P. R. Jones

A computer program was written for the design of a shell and tube heat exchanger on a price optimum basis for the following conditions: (1) Triangular pitch; (2) single or multiple pass; (3) heating or cooling; (4) no change in phase; and (5) inside pumping costs immaterial. Price optimum design was obtained for four standard tube sizes and standard pitch. The inside pressure drop was fixed and outside pressure drop was computed for the optimum baffle spacing and when the baffle spacing equaled the shell diameter. Standard shells whose areas equaled or exceeded the required area were also listed. The program was made adaptable to various fluids and to various tube sizes and pitch by reading in many of the required data such as physical properties of the fluids, tube data, and standard shell data in tabular form.

Jan 1, 1968

By H. G. Skavlem

This paper is prepared the United States Bureau of Mines and is descriptive of methods, practice, and costs at the McIntyre Porcupine Mines, Ltd., Schumacher, Ontario. The property is located in the Pearl Lake section of the Porcupine mining district. It is reached by a branch line of the Temiskaming & Northern Ontario Railway from Porquois Junction. There is also a good motor road into the district. The Hollinger Consolidated Gold Mines and the Coniaurum Mines, Ltd., are adjacent properties. Power for both the mining and the pulp and paper industries in the district is supplied by an extensive development of the water-power resources. Weather conditions are favorable for mining operations.

Jan 1, 1933

By Larry A. Haas

The U.S. Bureau of Mines, in cooperation with Cleveland-Cliffs, Inc. (Hibbing, MN), investigated ways of enhancing the quality (compressive strength, after-tumble and reducibility) of domestic acid and fluxed magnetite pellets by modifying the oxygen content during the preheat and induration periods of the firing operation . Oxidation of magnetite was best accomplished when sufficient oxygen and time were available before the peak induration temperature was reached. The rate of magnetite oxidation increased directly with the gas oxygen content during the preheat period at 7000 C and above. With 30 pct ( or more) O2 and a preheat rate of 2000 C/min, most of the magnetite was oxidized during the preheat period. With laboratory tube and mini-pot furnace tests, oxygen enrichment during the preheat period improved the pellet properties more in the simulated grate-kiln tests than in the simulated straight-grate tests. The longer induration period with the grate-kiln test resulted in more sintering of the residual magnetite and its reaction with the silicon compounds. When flux was present in the pellets, calcium silicates and calcium and magnesium ferrites were formed. More calcium ferrite was formed when the magnetite was oxidized early and less iron was present in the fayalitic calcium silicate slag.

Jan 1, 1993

By Ludwig Schmidt

Steel tanks often corrode rapidly in oil fields where the gas produced with crude petroleum contains an appreciable quantity of hydrogen sulphide. In many instances working tanks have been discarded after only six months of service because of failure induced by corrosion. Aluminum has been used for some time in the fabrication of certain equipment incidental to the handling of oils containing hydrogen sulphide gas in solution, and has exhibited no serious corrosive action. These uses indicated that aluminum tanks might be equally effective in counteracting hydrogen sulphide corrosion. Consequently, in the spring of 1928, an all-aluminum stock tank of 500 barrels capacity and a "composite" tank of equal capacity, having a steel bottom and bottom ring and an aluminum top and top ring, were placed in service on the State-Lassiter lease of the Gulf Production Co. in Crane County, Tex. These tanks were under observation for one year, the test being sponsored by the Gulf Production Co., the Aluminum Co. of America, rind the Parkersburg Ric and Real Co. The results of this preliminary test sustained the belief that aluminum is highly resistant to hydrogen sulphide gas and likewise indicated the type or grade of aluminum which could be most economically used for lease tankage. However, in this preliminary test the Wake were not subjected to contact with the large quantities of highly concentrated brines such as often are associated and produced with crude oil. Therefore, it was suggested by representatives of .the Aluminum Co. that additional tests be made to include production conditions in which large quantities of brine would be handled, for past experience had shown that aluminum often is susceptible to the corrosive action of brines.

Jan 1, 1931

By William J. Campbell

This Bureau of Mines report describes a study conducted to determine the relationship of mineral habit to particle size and shape characteristics for prismatic, acicular, fibrous, and asbestiform varieties of tremolite. Particle measurements were made with the petrographic microscope at X 1,250 and the scanning electron microscope at magnifications up to X 10,000. All of the varieties of tremolite, upon Wiley milling, produced a significant percentage of particles that meet the Federal regulatory criteria for counting as asbestos fibers. However, only the asbestiform variety gave milled particles that fell into a size range of >10 µm in length and <0.5 µm in width; some medical scientists consider this range significant for production of adverse health effects.

Jan 1, 1979

By E. P. Youngman

In the absence of any subsequent enactment of mining legislation, the Turkish mining law in effect in 1914, when Iraq became a British mandate, is still operative. The Constitution, or Organic Law, of Iraq, adopted by the Constituent Assembly on July 10, 1924, in articles 113 and 114, provides that:3 Ottoman en laws date and thao remained and lave pub- lished on or after that date and which have remained in force in Iraq u to the time of the publication of this law shall remain in force in Iraq' so far as circumstances permit, subject to any modi- fication or repeal in conformity with the proclamations, regula- tions, and laws referred to in the following article, and until they are altered or repealed by the legislative power or the High Court issues a decision rendering them null and void in accordance with the provisions of article 86. (Art. 113.) All proclamations, regulations, and laws by the Commander-in- Chief of His Britannic Majesty's Forces in Iraq, the Civil Commis- sioner, and the High Commissioner, and those issued by the Govern- ment of His Majesty King. Faisal, during the period between Novem- ber 5, 1914, and the date of the coming into force of this Consti- tution, shall be considered to be valid as from the date on which they came into force... (Art. 114.) 4 According to a German authority, it is the Turkish law of March 26, 1906, that, with a few modifications, is still in force. This law (similar to the French law of 1810) is discussed in a separate section of this paper.

Jan 1, 1933

By E. G. Erspamer

Laboratory investigations were made by the Bureau of Mines on ore containing the sulfides of both mercury and antimony to develop a method or methods for the economic recovery of mercury metal and the concurrent recovery of antimony as metal or salts,. If standard mercury-recovery techniques are applied to such ores, the antimony content interferes with the effective production of mercury metal; further-more, the antimony is lost. This report presents the results of tests on a sample of cinnabar-stibnite ore from the Red Devil mine near Sleitmute, Alaska. Red Devil ore was chosen for the investigation because it is purported to be typical of ores of the Kuskokwim River area, which, in their aggregate, constitute large potential reserves of mercury and antimony. Studies included petrographic, spectrographic, and chemical analyses, gravity-separation tests, bulk flotation of mercury and antimony sulfides, differential flotation, leaching, and furnacing of crude ore and of flotation concentrate.

Jan 1, 1956

By Michael A. Trevits

The National Institute for Occupational Safety and Health (NIOSH) in partnership with Strata Products tested the sealing capability of Ventstop®? as part of an ongoing mine fire control and suppression research program. Ventstop®? is a multi-purpose, inflatable device that is produced by Minvent Solutions and is available world wide for use in the metal and nonmetal mining industry. Ventstop®? is also used in the Australian coal industry as a temporary ventilation control device. The device can be quickly deployed, is reusable and can be placed in horizontal and vertical mine voids to control dust, fumes and smoke. Deployment, multi-day inflation and air leakage tests were conducted at the NIOSH Lake Lynn Laboratory to determine the capability and limitations of Ventstop®? in a simulated coal mine setting. During the tests, Ventstop®? was also subjected to low level forces of a nearby methane gas ignition. It is thought that Ventstop®? could be used by the US coal mining industry to temporarily close an underground mine area in response to a fire or spontaneous combustion heating event, to temporarily redirect mine ventilation during longwall equipment moves or during stopping construction. This paper describes this inflatable temporary mine sealing technology and presents the results of the NIOSH tests. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of NIOSH.

Jan 1, 2009

The purpose of Volume II of this study is to provide a general plan for the pilot testing of two materials which could be used to tag explosives for both pre- and postdetonation identification and of tracing techniques which would thereby aid the investigator of an unauthorized bombing or explosion in being able to determine the source and/or user of the explosives. Volume I described the planning factors by which the tagging of explosives could be implemented on a National basis. 1.2 BACKGROUND Tagging explosives at the time of manufacture with a taggant material that could survive detonation, be recovered, and provide an investigative lead has been seriously studied for several years. This concept has gained widespread support among many law enforcement groups because of the scant clues that can presently be found among bombing residue.

Jan 1, 1977

By L. M. Chan, D. H. Carlson, J. H. Johnson

"This paper discusses the evaluation and application of a portable parked-vehicle tailpipe emissions measurement apparatus (EMA). The EMA consists of an exhaust dilution system and a portable instrument package. The EMA instantaneously dilutes and cools a sample of exhaust with compressed nitrogen or air at a known dilution ratio, thereby presenting it to instruments as it is presented to personnel in the surrounding environment. The operating principles and governing equations of the EMA are presented.A computational method is presented to determine the engine operating and performance parameters from the exhaust CO2 concentrations along with an assumed engine overall volumetric efficiency and brake specific fuel consumption. The parameters determined are fuel / air ratio, mass flow rates of fuel, air and exhaust emissions, and engine brake torque and horsepower. These calculated engine parameters are used to characterize engine load when performing EMA in-field tailpipe sampling without a dynamometer, and to detect deteriorated engines.Evaluations of the EMA by comparison of diesel tailpipe measurements with those made using laboratory-grade instruments showed that the EMA measurements are accurate and reproducible. The results also show that the EMA is capable of detecting emission concentration changes resulting from engine faults. Calculated engine operating and performance parameters correlate and compare well with laboratory-measured values.The EMA in-field engine loading and tailpipe sampling procedures for parked vehicles are presented, and results of the EMA field measurements are also presented. Low coefficients of variation for repeat EMA tailpipe measurements on diesel-powered haulage vehicles in four underground mines indicate that the EMA in-field engine loading and tailpipe sampling procedures are reproducible.An analysis of EMA tailpipe measurements for three haulage vehicles in one mine shows that the EMA can: 1) identify haulage vehicles that emit excessively high pollutant concentrations, and 2) provide data needed to evaluate and determine the efficiency and effectiveness of tailpipe emission control devices.Finally, recommendations for a proposed commercial EMA system are presented. This commercial system would overcome many of the adverse features of the prototype EMA used in these tests."

Mar 1, 1992

By R. A. Beall

As part of an ongoing program to develop high-quality materials with improved performance and service lives, and to conserve critical minerals, Bureau of Mines, U.S. Department of the Interior, researchers studied the process of hot-rolling metals, alloys, and composites in vacuum. First, a comprehensive review of the literature is presented, including the advantages and disadvantages of using vacuum. Next, details of hot-rolling titanium, chromium, and molybdenum-iron bimetal are given. Finally, the design of new equipment is described. At this time, it is uncertain whether hot-rolling metals in vacuum will gain commercial acceptance in the future.

Jan 1, 1979

By K. E. Robinson

This study provides an initial indication that mill tailings produced in the Coeur d&apos;Alene Mining District of Idaho can be placed on floodplain areas in a technically acceptable manner without artificial liners and without seriously contaminating the surrounding area. Tests have shown that landfills on these unused areas can result in returning these areas to productive use. The engineering properties of mill tailings permit construction of stable embankments. Designed slope protection inhibits water erosion. Among the environmental considerations in using tailings for landfill construction are the acid and other contamination produced by tailings and wind erosion of exposed tailings surfaces. The initial results indicate that adverse impacts are not as severe as previously thought, and mitigative measures are feasible. Based on the preliminary data, and in accord with existing Federal and State waste management regulations, a conceptual design has been developed for 23 potential landfill sites in the District, which could reclaim 750 acres of floodplain. A cost analysis of landfill construction with mill tailings indicates that the method would be an economically viable means for increasing the valleywide tailings storage capacity, provided construction with slurried tailings is feasible. A Stage H study is proposed to evaluate slurried tailings as a foundation material, as opposed to hauled tailings used in this present study.

Jan 1, 1981

By John J. Sammarco

This report details the testing and evaluation of a modular azimuth and positioning system (MAPS) to provide navigational information for a continuous mining machine. Vehicle navigation is part of the U.S. Bureau of Mines research program in computer-assisted mining serving as a tool to increase mining health, safety, and productivity. The Bureau is investigating other navigation systems, but MAPS seems to have the most promise. MAPS was installed on a continuous mining machine. An operator used the machine to cut coal while researchers collected machine and MAPS data. A comparison of MAPS data for xy position and data obtained with an electronic transit showed an increasing error for MAPS. After 30 min of operation, the easting position error was -0.02 m, and the northing position error was 0.019 m; after 60 min of operation, the easting position error was -0.19 m, and the northing position error was -0.26 m. Modifications to MAPS software and to the operational procedure of the machine significantly reduced this error by a factor of 3.7. Researchers continue to reduce these errors.

Jan 1, 1993

By A. J. Kraemer

This paper is the third and concluding report of the results of the United States Bureau of Mines twenty-third semiannual survey of motor fuel marketed in the United States. The first paper, reporting data relative to gravity, vapor pressure, and distillation range of the samples, was published as Report of Investigations 3129. The second report dealt with the data of the twenty-third survey in accordance with the revised specifications for United States Government Motor Gasoline. These data were published as Report of Investigations 3142.

Jan 1, 1931

By E. D. Gardner

The mine of the Eureka Standard Consolidated dining Co. is at Dividend, Utah, in the Tintic mining district. It is operated under the same management and controlled by the Antic Standard Mining Co.; the two properties adjoin each other. The Eureka Standard is worked through a vertical shaft; the ore is mined by a stringer-set-and-fill method. One hundred and thirty men were employed in April 1933. The normal daily tonnage is 100 tons; the ore is shipped to the smelter at Garfield, Utah.

Jan 1, 1935

By Nicholas Kyriazi

A joint effort by the U.S. Bureau of Mines (USBM) and the U.S. Mine Safety and Health Administration (MSHA) was undertaken to determine how well self-contained self-rescuers (SCSR&apos;s), deployed in accordance with Federal regulations (30 CPR 75.1714), held up in the underground environment with regard to both physical damage and aging. This report presents findings regarding laboratory-tested SCSR&apos;s in the fourth phase of testing from 1989 to 1993. The SCSR&apos;s were tested on human subjects and on a breathing and metabolic simulator (BMS). These results indicate that most of the apparatus, if they pass their inspection criteria, perform as expected except units with manufacturing defects. However, when the apparatus are carried in and out of the mine daily and stored at the working section, they may suffer abuse. Physical signs of abuse, unless extremely obvious, are frequently not detected by the miners or mine operators. In addition, some apparatus collected for this study had not been returned to the manufacturer in a recall effort for correction of a manufacturing defect. In both cases, the apparatus would have presented problems in emergency use. Recommendations include improved training in inspection procedures and better enforcement of recall notices.

Jan 1, 2010

By A. J. Kraemer

This paper is the third and concluding report of the results of the United States Bureau of Mines twenty-third semiannual survey of motor fuel marketed in the United States. The first paper, reporting data relative to gravity, vapor pressure, and distillation range of the samples, was published as Report of Investigations 3129.7 The second report dealt with the data of the twenty-third survey in accordance with the revised specifications for United States Government Motor Gasoline. These data were published as Report of Investigations 3142.8

Jan 1, 1931

By R. G. Bottge

To better understand those factors which increase mining costs in Alaska, a Bureau of Mines study was conducted to compare the estimated costs of operating a 100,000-tpd open pit copper mine located on a hypothetical ore body in the Lake Clark area, Alaska, with the costs of mining a similarly sized hypothetical copper ore body near Tucson, Ariz. The information derived should be beneficial to the State and Federal governments in appraising the potential for development of large, low-grade porphyry copper deposits in south-central Alaska. Conventional mining and concentrating methods were assumed, and capital and operating costs were derived using flowsheets and standard costing methods. The total price required for copper mined in Alaska and Arizona was $1.12 and $0.63 per pound, respectively, plus or minus 20 percent. These values were obtained assuming no leaching of low-grade copper, recovery of gold, silver, and molybdenum as byproducts, 100-percent equity financing, and a 12 percent discounted cash flow rate of return. The average domestic and international prices for copper in July 1973 were $0.60 and $0.916 per pound, respectively. The existence of a developed transportation and power system in Alaska would have reduced capital and operating costs subs tantially. The required price for copper would have declined from $1.12 to $1.05 per pound, plus or minus 20 percent.

Jan 1, 1974