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By D. A. Reynolds, A. C. Fieldner, S. H. Katz

"03-01-192403-31-2019RI 2591 - Reports of Investigations - Department of the Interior - Bureau of MinesBureau of MinesPittsburgh Experiment Station American Society of Heating and Ventilating EngineersU.S. Public Health ServicesTucson Experiment Station Introduction.""Carbon monoxide self-rescuers,"" or simply ""self-rescuers,"" are pocketsize gas respirators which protect the wearer from air contaminated with poisonous carbon monoxide gas. On March 6, 1924, the Bureau of Mines approved the ""M.S.A. self-rescuer’ manufactured by the Mine Safety Appliances Co., Pittsburgh, Pa., after the M.S.A- self-rescuer bad passed all the tests and requirements of the Bureau's Schedule 14A4.The purpose of the self-rescuer is to help miners to escape from mines in which fires are burning or explosions have occurred, by providing protection from carbon monoxide for at least one half-hour. The self-rescuer can be used similarly by workers above ground who may through accident become surrounded or entrapped by atmospheres containing carbon monoxide.no hazards threaten the miner, who escapes serious injury by fire or violence in a large mine fire namely, ( 1) asphyxiation by poisonous carbon monoxide gas; and (2) suffocation by insufficient oxygen to support life. In order to save himself, the miner must either erect a barrica4e5 against afterdamp and wait restoration of ventilation and rescue or take a long chance at getting out of the mine through entries not permeated by afterdamp.. The self-rescuer removes the hazard of carbon monoxide poisoning for one half-hour or more, and accordingly greatly increases the miner's chance of saving his life.This paper describes the construction and details of the M.S.A. self-rescuer as approved by the Bureau of Mines, and discusses its performance under test condition"

Mar 1, 1924

By Wilber Duvall, Leonard Obert

"INTRODUCTION This report is the first of four to be presented on the microseismic method 4/ of predicting rock failure in underground mining. The application of the microseismic method to one specific case, namely, that of predicting rock bursts in deep mining, has been described in two previous reports. 5/ 6/ Since the publication of these reports 5/ 6/ the method has been extended to other fields of mining, end it is the purpose of this report (Part I) to describe the general microseismic method, giving the empirical facts upon it is based, the different testing procedures, the method of recording and analzing the data, and the interpretations that can be obtained there-from. Part II will describe a series of laboratory experiments that were performed to give information on the origin of microceismims and the microseismic properties of various rocks. Part III will cover application of the method to specific mining problems together with a brief description of a number of investigations performed during, the last three years. Part IV will describe in detail the microseicmic equipment used in the various phases of these investigations."

Feb 1, 1945

By Leonard Obert

[Tng occasional. rock noises in a nice caured by brc,*ing and ripping of the back, settling, and other cailscr, are well-known tc~ a11 mining en- gineers. These noises oftcn prececte certnin tpes of rock failure as such are used to e certain event a; w:,rnlngs. Senides t5ese audible rock noisee t'nere are, l?o\;evpr, even Iprger nw.iber of' s;Lba.J^;li5le rock mis~s, which must; be piclcell UT with sole type of vi-urr,tion rnicroyhoce and qli- fied in order tnnt :hey n;ny e heard. It v:zs s~v;,yestec" Ir, an evlier ? ,I a.ldible noises Ifureau of I.lines s~zb:ic;et.iod that n stud:r of t!ler;c! *- t mig!!t be useful ir. de temining roc^ movemrnt 3 preceding failure.]

Jan 1, 1941

By M. J. Ankeny

All bituminous-coal mines, by the nature of their product and inherent gassy tendencies, are subject to explosions or mine fires. The evolution from large, hand-loading sections employing numerous men and containing open-type equipment, lights, and nonpermissible explosives to small, concentrated mechanical sections with but few well-supervised men utilizing modern preventive equipment has not altered this premise. Mine catastrophes such as Centralia and New Orient No. 2, as well as recent disasters of less magnitude, have refuted the trend of thinking that modern equipment, will prevent or localize explosions and prevent widespread or loss of life.

Jan 1, 1952

By Benjamin Petkof

Production quarry blasts in three rock types were photographed with a high-speed camera. Analysis of the films showed that step increases sometimes occur in the horizontal velocity of the broken rock. These step velocity increases were observed only in the first foot or so of rock movement. This observation indicates that the gaseous products of the explosion do additional work on the rock after it is crushed and cracked by the initial compressive-stress pulse and the reflected tensile-stress pulse. The observed initial fly-rock velocity is compared with the calculated fly-rock velocity for reflection spalling. A mechanism possibly causing the velocity increases is discussed. INTRODUCTION When a small concentrated charge of explosive is detonated at the bottom of a drill hole near a free surface, two modes of rock failure have been observed; both are associated with the stress pulse generated in the rock by the detonating explosive. The first mode of failure is the crushing and radial tensile cracking associated with the initial passage of the compressive-stress pulse as it propagates outward from the explosion. This type of rock failure is usually confined to the immediate vicinity of the charge hole. The second mode of failure is the tangential and radial tensile cracking associated with the tensile-stress pulse that is reflected from the free surface. This mode of failure is commonly called scabbing or spalling and has been shown to be a primary cause of rock failure in crater formation at one free surface. (3).4

Jan 1, 1961

By L. D. Tracy

The first study of this subject hits been made in Illinois, but as opportunity affords, similar studies will be made in other States. It is hoped that the data obtained will assist the coal-mining industry to standardize the forms of leases, and so avoid some of the abstruse and ambiguous clauses which slay be found in many of them and the consequent liability of costly litigation. In some of the publications of the Illinois Mining; Investigations prepared under a cooperative agreement with the U. S. Bureau of Mines, the Illinois State Geological Survey and the Engineering Experiment Station of the University of Illinois, the coal areas of the 'State have been divided into eight geological districts, each district being treated separately. This report covers District No. VI of that classification, and it is hopped that studies of the other districts will be completed in the near future and similar results published.

Jan 1, 1926

By W. R. McDonald

The Bureau of Mines, U.S. Department of the Interior, conducted small-scale field tests on acidic copper tailings as part of its effort to develop, improve, and demonstrate technology for stabilizing mining and mineral-processing wastes. Two successful demonstration revegetation plots were established on an abandoned copper-tailings pond located on public land adjacent to Holden Village, Wash. The tailings were neutralized with treatments of either dolomitic lime or limerock and fertilized with processed sewage sludge and/or commercial fertilizer. Excellent plant growths covering 70 and 24 percent of the surface were achieved on 1/8-and 1-1/2-acre test plots planted in 1973 and 1974, respectively. Regar brame, Tegmar intermediate wheatgrass, and tall wheatgrass provided the best plant growth and surface coverage. The target pH of tailings neutralization was 6.8; however, good plant growth occurred in areas where the soil pH ranged from 2.9 to 5.8.

Jan 1, 1978

By J. P. McGee

As part of a joint U.S. Atomic Energy Commission-Federal Bureau of Mines program for using nuclear energy to supply process heat, a simulated nuclear loop has been constructed to test components. This loop has been operated for more than 1,800 hours at 100 p.s.i.g. Of this period, 23 hours were at 2,500° F. and higher; 540 at 2,000° to 2,500° F.; 840 at 1,500° to 2,000° F.; 200 at 1,000° to 1,500° F.; and 260 below 1,000° F. Leakage at flanges and welds was not a serious problem. A helium-recycle system with gas temperatures of 2,300° to 2,500° F. and a static pressure of 250 p.s.i.g. appears feasible. Difficulties were encountered with the recycle compressor due to thermal distortion of the impeller and shaft. The use of sealed bearings limits compressor operation to the life of the bearings.

Jan 1, 1960

By Bryan F. Ulrich

If resin-grouted roof bolts are not installed correctly, mine roof reinforcement can be affected, and roof falls can result. A bolt installation variable that is readily controlled by the mine operator is annulus thickness. The objective of this U. S. Bureau of Mines investigation was to study the effect of annulus thickness variations on the integrity of 3/4-in-diam resin-grouted bolts. Forged-head test bolts, 2 and 1 ft long, were installed in concrete blocks that had been drilled with 1-, 1-1/8-, 1-1/4-, 1-3/8-, and 1-1/2-in-diam bits. Standard pull tests were performed; then the concrete was broken away from the bolts so that grout mix quality could be inspected. It was found that the optimum annulus thickness is 1/8-in (l-in-diam drill hole), and as annulus thickness increases from the optimum, there is a corresponding decrease in grout mix quality, effective grout ratio, and axial stiffness.

Jan 1, 1989

By Liming Yuan

Three-dimensional computational fluid dynamics (CFD) modeling is conducted to simulate spontaneous heating in a large-scale coal chamber with a forced ventilation system. Spontaneous heating is modeled as the low-temperature oxidation of coal using kinetic data obtained from previous laboratory-scale spontaneous heating studies. Heat generated from coal oxidation is dissipated by convection and conduction, while oxygen and oxidation products are transported by convection and diffusion. The water vapor transfer and the effect of heat of wetting are not modeled. The CFD model is validated by comparing simulation results with test results from U.S. Bureau of Mines experiments conducted in the coal chamber. The model predicts lower temperatures in the early stage but agrees well on the induction time for spontaneous heating. The effects of airflow rate and order of reaction on the spontaneous heating process are also examined. The calibrated CFD model is found to be useful for predicting the induction time for spontaneous heating in underground coal mines.

Jan 1, 2009

By J. L. Ambs

The U.S. Bureau of Mines (USBM) Diesel Research Program emphasizes the development and evaluation of emission control devices to reduce exposure of miners to diesel exhaust pollutants. Studies by the USBM have shown that diesel exhaust aerosol (DEA) contributes a substantial portion of the respirable aerosol in underground coal mines using diesel equipment not equipped with emission controls. The USBM and the Donaldson Co., Inc., Minneapolis, MN, have developed a low-temperature, disposable diesel exhaust filter (DDEF) for use on permissible diesel haulage vehicles equipped with waterbath exhaust conditioners. These were evaluated in three underground, mines, to determine their effectiveness in reducing DEA concentrations. The DDEF reduced DEA concentrations from 70 to 90 pct at these mines. The usable life of the filter ranged from 10 to 32 h, depending on factors that affect DEA output, such 'as mine altitude, engine type, and duty-cycle. Cost per filter is approximately $40.

Jan 1, 2010

By W. L. Cornell

The Missouri Pb ores are the only domestic Co resource being mined and processed for other metals; therefore, they present a viable short-term opportunity for Co production. Lead, zinc, and copper concentrates are produced from the ore. The Cu concentrate can contain up to 30 pct Co and the Pb concentrate up to 15 pct Co. Since Co is detrimental to the processing of the Zn concentrate; the remainder of the Co is rejected to the tailings. The tailings can contain as much as 50 pet Co originally present in the mined ore. Researchers at the U.S. Bureau of Mines have successfully tested on a continuous basis a process that recovers a bulk sulfide concentrate from mill tailings. The concentrate contains up to one-half of the Co and from 50 to 90 pct of the Pb, Zn, and Cu. Concentrate weight represents 10 pet or less of the total tailings.

Jan 1, 1989

By Paul W. Jeran

Subsidence was monitored by the U.S. Bureau of Mines over the ends of longwall panels operating in the Pittsburgh, Kittanning, and No. 2 Gas Coalbeds of the northern Appalachian Coal Basin. The final subsidence over the finishing ends of three panels in the Pittsburgh Coalbed are compared with the subsidence measured over the rib at these panels. The characteristics of subsidence are different. At Mine A, data over the start of a longwall panel shows similar characteristics to the subsidence measured over the rib. Subsidence over the fmishing ends of panels in the Kittanning and No.2 Gas Coalbeds are also different from the subsidence over the rib. The use of a subsidence prediction model based on data gathered over the rib of a panel will not yield accurate results if it is applied to the finishing end of a longwall panel. Acceptable results may be obtained along the centerline over the starting end of a panel.

Jan 1, 1991

By P. Comba

The U.S. Bureau of Mines investigated a hydrochloric (HC1)-calcium fluoride (CaF2) leaching procedure to treat domestic manganese (Mn)-bearing silicate resources. The proposed process is an alternative to high-temperature and energy-intensive extractive techniques. Single-stage leaching with a stoichiometric amount of HCl and a F-Mn mole ratio of 0.2 extracted 96 pct of the Mn when the leach conditions were 50° C, 3 h, and 35 pct solids. Ninety-eight percent of the Mn was extracted during countercurrent leaching at similar conditions. A process flowsheet was developed that incorporated HC1-Cab leaching, excess leach acid utilization, fluoride (F) recycle, and Mn recovery. When the domestic manganese silicate ore was processed, 98 pct of the Mn was extracted, 99 pct of the Cab was reclaimed, and a leach residue was produced that passed the Environmental Protection Agency (EPA) Extraction Procedure (EP) Test for nonhazardous waste.

Jan 1, 2010

By Gary P. Sames

This report discusses some practical applications of a geotechnical investigation conducted by the U.S. Bureau of Mines that can help mine operators meet revised Federal regulations in their roof control plans. The investigation, designed to characterize roof conditions near the coalbed outcrop in drift coal mines in eastern Kentucky, revealed that weathered stress-relief joints near outcrop are crucial ground control factors in the region. The joints' origin and character were determined through underground mapping of many joints in coal mine roof and detailed observations and measurement of joint trends and physical characteristics in widely separated strip mine highwalls and roadcuts. This resulted in an understanding of stress-relief-joint patterns and the effect of various rock types on the intensity of weathering in the joints. That information is used in this report to show how stress-relief joints contribute to roof failure and how, through improved roof support and mine planning, safer roof support plans can be developed.

Jan 1, 1992

By William C. Laubengayer, Robert R. Godard, Harry Dobroski

A whole mine, computer-controlled communication and monitoring system for both normal and emergency use is installed and operating in the U.S. Steel Robena Mine complex near Uniontown, Pa. Portions of the system, including the coaxial cable and the key underground and surf ace phones, have been operating for over a year and a half. During this time the basic concept has been modified and new line amplifiers with directional switches have been developed to eliminate some problems in implementing the loopback feature. The quality of the audio and the availability of the system have been outstanding. Since early summer almost all subsystems have been completed. The experience with the telephone system itself, the pocket-pager call alert, section wireless radio, hoistphone, television, environmental monitoring, control and monitoring of equipment, voicedownlink/code uplink post disaster communications, post disaster through-the-earth monitoring, and the system center failure diagnostic routines are reviewed.

By James H. Russell

The Bureau of Mines, U.S. Department of the Interior, in cooperation with the Department of Energy, has attempted to increase the activity of nickel catalysts for converting synthesis gas, derived from coal, to a substitute natural gas. This report describes the effects of low-level additions of B, Ca, Ce, Co, Mn, Mo, Pd, Re, Ti, Y, Zn, and Zr on the methanation activity of Raney nickel. The methanation rate at 320° C and the resistance to poisoning by 2 ppm H2S were used to compare catalysts. The effects of the additions were small, and the experimental variances were large, necessitating the use of statistical methods to identify significant effects. Co, Ti, Y, and Zn improved the resistance to H2S poisoning, but only Co improved the methanation rate In some individual catalysts containing Ca, Mo, or Mn, both the methanation rate and resistance to H2S poisoning were improved.

Jan 1, 1980

By Maria I. De Rosa

The U.S. Bureau of Mines performed experiments to determine if the primary gas toxicities evolved during the early (-300° C) and later (>400° C) combustion stages of mine conveyor belts could be predicted by a smoke particle characteristic. The experiments were conducted in an approximately 20-L furnace at set furnace temperatures of 150°, 250°, and 1,000° C, with a furnace airflow of 10 L/min. The variables studied, as a function of time, included hydrogen chloride and carbon monoxide concentrations, the average smoke particle diameter (d8 and number concentration (no), and the product of the average smoke particle diameter and concentration (dgn0) Other variables included the sample and furnace temperatures and the sample mass weight loss. Results show that the inverse of the smoke particle diameter-concentration product (ldgn0), correlates directly with the hydrogen chloride and carbon monoxide toxicities released in large quantities during the early and later stages of combustion.

Jan 1, 1989

By Jalna R. Zatko

The Bureau of Mines, U.S. Department of the Interior, has developed a novel method of flocculation dewatering of phosphatic clay wastes using polyethylene oxide as the flocculant. Research was conducted to determine whether ethylene oxide gas was present in the air in the vicinity of disposed waste materials which had been flocculated with polyethylene oxide. Samples of clay waste materials containing polyethylene oxide were prepared in stoppered glass bottles in simulated disposal environments. Gaseous samples, removed over a 75-day period using an airtight syringe, were injected into a gas chromatograph that was capable of separating ethylene oxide from air. The presence of ethylene oxide gas was not detected in any sample. To determine possible degradation products of polyethylene oxide, the properties and reactions of ethylene oxide and its polymers were reviewed. Based upon the literature survey and experimental study, it was concluded that adverse environmental effects were not likely to result from the use of polyethylene oxide for flocculating phosphatic clay waste products.

Jan 1, 1980

Determine safe practices for surface mine blasting near pressurized gas, oil, and water transmission pipelines. Background Surface mine blasters regularly have to address the issue of how blasting affects transmission pipelines that run near and sometimes through their permit areas. Regulatory approaches to blasting have ranged from no regulation at all to strict limits intended to prevent cosmetic cracks in plaster interior walls of homes, but they have not directly addressed the impact of blasting on nearby pipelines. Concerned with both productivity and safety, the mining industry and its regulators have requested guidance on safe practices for mining near pipelines. The Pipeline Research Group of the American Gas Association has sponsored studies of the effects of small close-in blasts because of vibration concerns related to the installation of new pipes into existing pipeline right-of-ways. By contrast, the recent study in which the U.S. Bureau of Mines (USBM) took part is the first addressing large-scale mining blasts.

Jan 1, 1995