Search Documents

By J. E. Tiffany, Z. C. Gaugler

This supplement has been prepared to furnish information on amendments to the regulations that were approved by acting secretary of the Interior on June 24, 1946, while this report was in the press. Page 14, item 2, and page 20, item 4, have been amended by the addition of the following footnote: "Pending the development of a satisfactory multiple-shot permissible blasting unit, a blasting unit of Type II, Class A, covered by Federal Specification WB 411, December 31, 1941 (with or without Amendment 2, June 16, 1945), may be used until Decem- ber 31, 1947. Should a satisfactory multiple-shot permissible unit be made available prior to that date, this interim approval may be terminated." Page 14, footnote / has been amended to read as follows: "The use of charges over 1-1/2 pounds and not exceeding 3 pounds is approved pending further investigation. The approval, which may be withdrawn at any time, expires December 31, 1947, unless renewed. For charges over 1-1/2 pounds, the following additional requirements must be observed: (1) Shot holes must be 6 feet or greater in length. (2) Explosives must be charged in a continuous train with no cartridges deliberately deformed or crushed, with all car- tridges in contact with each other, and with the end cartridges touching the rear of the hole and the stemming, respectively. (3) The permissible explosive must be one showing toxic gas omission that will place it in either Class A or Class B."

Jan 1, 1947

By Michael D. Fenton

The very modest-sized mineral industry of Afghanistan was burdened for another year with problems of internal strife occassioned by the presence of Soviet armed forces. Despite this, production of the few traditional commodities continued, and the mineral industry moved to develop additional mines and plants for both traditional and new products with considerable technical and construction assistance from the U.S.S.R. Among the limited range of mineral commodities for which production was reported, there were no startling changes between 1984 and 1985. Production of both coal and natural gas advanced only slightly, despite substantially higher 5-year plan goals, and cement output was down marginally. Probably the most significant development in 1985 was the Possibility that mine and/or smelter production of copper was initiated during the year.

Jan 1, 1987

By J. C. Hartley

The most important single operation in mining is the ventilation of underground areas in a manner conducive to the health and safety of employees. Adequate volumes of pure air must be supplied at the working faces, along the haulageways, and wherever men work, so as to dilute and carry away the methane liberated from the coal and adjoining strata, noxious gases evolved by the use of explosives, and the carbon dioxide exhaled by men and formed by oxidation of carbonaceous material, as well as any other gases, and also dusts which may be found in mine workings. A sufficient quantity of air must also sweep abandoned or worked-out areas of the mine to prevent the accumulation of gases, where sealing methods are not utilized to isolate old workings. Air, in a quantity adequate to meet the needs of the particular mine to which it is applied, is necessary, and supplying it can be made very expensive through failure to observe good practices in its direction and apportionment." Leaky stoppings, doors, and overcasts rob the working faces of air and add to the ventilating cost by burdening the fans with fugitive air,

Jan 1, 1944

By L. C. George

The Bureau of Mines measured the vapor pressures of selected mixtures in the binary systems CdCl2 ?SnCl2, CdCl2 -ZnC12, PbCl2 ?SnCl2, and PbCl2 -ZnCl2 by the static pressure method. These data were evaluated by the second-law (sigma-plot) method. Equations expressing the vapor pressures and the heats and free energies of vaporization as functions of temperature are given.

Jan 1, 1969

By J. W. Horne

The United States Bureau of Mines in cooperation with the State of Colorado at the University of Colorado has conducted experiments to determine the amount and composition of the noncondensable cases evolved when crude shale oil is distilled under pressure. Hydrogen sulphide is one of the components found in the complex mixture of uses produced by the distillation of shale oil under pressure. This paper deals with the apparatus and method used in determining the amount of hydrogen sulphide evolved in the laboratory experimental cracking stills.

Jan 1, 1931

By P. J. Dallimore

The Bureau of Mines has calculated general time-dependent solutions for radon diffusion from cylindrical and slab rock samples containing uniform radium distribution. Results have been obtained for several sets of boundary conditions. The method is suitable for determining the effective diffusion coefficient and the effective porosity for radon.

Jan 1, 1983

By Marie Farnsworth

"The Anhydrite ProblemThe Nonmetallic Minerals Experiment station of the Bureau of Mines at Rutgers University, New Brunswick, N. J. has recently undertaken a study of the chemical and physical properties of anhydrite having in view its wider utilization anhydrite (CaSO4) in contact with water at ordinary temperature and pressure rehydrates, slowly forming gypsum (CaSO4.2H42O). In nature this is an extremely slow process, and laboratory experiments are being conducted to determine methods of accelerating the rehydration. The tests recorded herein cover one this study, and while they are negative in character in so far as the major problem is concerned, certain facts established by the tests, bearing on the stability relations of gypsum and anhydrite seem sufficiently important to be placed on record.Early Researches on Gypsum and Anhydrite.It is to Lavoisiar that we are the first scientific study of the calculation and hardening of plaster of Paris. He sums up his experiments in the following passage: ""If gypsum, which has been deprived of its water of by means of heat, is again treated with water (to make what is commonly called mortar) it takes it up with avidity, rapid and irregular crystallization occurs, and the small crystals which are formed are so entangled in each other that a very hard mass results."" Later, he observed that the dehydration of gypsum occurs in two stages: three-fourths of the combined water is much more easily driven out than the last fourth. LeChatalier first determined the temperature decomposition accurately, his method was as follows: Pulverized gypsum was placed in a glass tube in the middle of a paraffin bath, the temperature of which was raised in a progressive and regular manner. A thermometer gave at each instant the temperature the salt, and the passage of the mercury column past each division of —co. was cared by a registering chronograph. The rise in temperature was except at 128°C. and 168°C. where breaks occurred."

Nov 1, 1924

By J. D. Davis

From the chemist's point of view it would be ideal if specifications for coke for any stated purpose could be written on the basis of chemical composition and burning characteristics. Unfortunately this is not possible. In fact, the physical properties of a coke are often of such major importance as to render any specified chemical requirements totally inadequate to show the quality of coke desired. For example, a furnace coke may admirably fill all chemical requirements, such as for low phosphorus, sulphur, moisture, and high fixed carbon, and still be too soft to support the burden of the furnace without excessive crushing. Again, a domestic coke though a good fuel as judged from Chemical analysis, may be of unmarketable size. Thus one can not define the quality of a coke for a specified purpose without taking into account both its chemical and physical characteristics even when this has been done the specification may fail because neither coke user nor producer can accurately define by quantitative tests the qualities most desired. In other words, there is need of accurate test methods for measuring the properties of coke and, what is equally important, for correlating the results with the behavior of the coke in use. Coke quality is determined by the kind of coal used, the coking process, and the type of equipment used in the coking process. Chemical analysis of the coals, together with small-scale coking tests, will give a good indication of their suitability; but, in general, coke must be produced on an industrial scale and tested in the equipment for which it is intended before conclusive information as to its quality is obtained.

Jan 1, 1928

By F. S. Crawford

Mining companies are usually held responsible for accidents occurring to the public around their operations . Safeguards are provided by progressive mining companies to prevent the public from getting into danger from wandering unattended about the properties . At abandoned operations , where little or no supervision can be maintained , persons are often injured through the negligence of the operator in leaving the property in unsafe condition . After a mine is abandoned or a lease is given up by a mining company , the responsibility for the safety of the property rests sometimes with the State to which the property ownership reverts or with the owner of the land ; either is usually quite unwilling to spend any money to remedy unsafe conditions due to the carelessness of the mining company . The land owner or the State , or both , should see that the work of leaving safe conditions behind is done by the operator before he abandons the mine or gives up the lease . Some of the worst hazards to the public at abandoned mines are from old test pits , abandoned shafts or tunnels , open pits , caved ground , and bodies of water in abandoned open pits . Hazards exist from some of these sources during the active operation of a mining property as well . In the early stages of mining operations test shafts are often sunk from 50 to 100 feet deep through the more or less loose material overlying bed rock . When these shafts are left unprotected , they are a serious danger for many years to come . In the course of time they become largely concealed by brush and grass , and thus are a deadfall to anyone who might happen to step into them . This condition will hold true for any part of the country, but to a much less degree where it is not necessary to sink through a great amount of cover . Many progressive operating companies have adopted the practice of filling in test pits after securing the information desired . Some nonresident landowners and exploration companies , however , have left such pits open , and it is extremely difficult for the mine inspector to get into communication with the owner . Frequently operating companies voluntarily fill test pits on adjacent property not

Jul 1, 1930

By L. C. IlsLey

As part of its work for the improvement of safety conditions in mines , the Bureau of Mines has undertaken to establish a list of permissible storage - battery locomotives for use in gaseous mines , and , to this end , has issued Schedule 15 , "Procedure for Establishing a List of Permissible Storage -Battery Locomotives for Use in Gaseous Mines . " Up to the present time , two approvals * have been issued under this Schedule , and considerable testing work done on four other applications which have been made for approval . Prior to the publication of Schedule 15 , the Bureau conducted both field and laboratory investigations to determine the hazard from the batteries used in mine locomotives . ** These investigations indicated that the safety of the locomotive would depend largely on proper care of the battery , also on the use of a battery as mechanically rugged as possible . For this reason the Bureau staff , in testing locomotives submitted for approval , considered it advisable to subject the batteries to a jarring or bumping test to prove their adequacy as regards mechanical endurance and ruggedness . These tests on the batteries of the locomotives are described below.

May 1, 1922

By W. Wan, R. V. Ramani, J. M. Mutmansky

"Diesel particulate matter (DPM) emitted from diesel engines is currently considered to be a health problem in underground mines. As a result, attempts have been made to control DPM both by reducing emission rates and by managing the DPM that gets into the mine atmosphere. This paper presents a method for modeling the generation, transfer, and distribution of DPM in coal mining sections through the use of a convection-based computer model so that controls for emitted DPM can be evaluated. A variety of ventilation strategies and diesel deployment schemes for room-and-pillar development sections were simulated to compare their effects on average DPM concentrations at several fixed and mobile personnel locations in the section. Input data for the model was gathered from actual diesel development sections and derived from experimental study results provided by other researchers. Analyzed using the model were ventilation schemes using vent tubing and brattice, exhaust location strategies on the vehicles, and the direction of ventilation at the feeder-breaker location. A summary of results from this study is presented.With diesel equipment holding an important place in underground coal mining and growing in use over time, it is important to develop and improve controls of the exhaust emissions, especially diesel particulate matter (DPM), to further reduce potential health hazards. The proper design and maintenance of diesel engines and on¬board control procedures are paramount requirements for controlling DPM successfully. There is also, however, a significant reduction potential in terms of personal exposure that can be realized by managing the DPM that gets into the airstream. Strategic design of the mining, ventilation, and equipment implementation systems remain essential for efficiently reducing the DPM concentrations.Modeling the effect of diesel exhaust contaminants upon the mine atmospheric quality will permit improved health and safety design of the overall mining and ventilation systems. Numerous studies have been performed to model the distribution/transport of gaseous and particulate emissions in the underground mine atmosphere and some very sophisticated convection/diffusion models have been developed (Skobunov, 1974; Thakur, 1974; Stefanko and Ramani, 1975; Wala, 1980; Bandopadhyay and Ramani, 1983). Most of these models were developed for a single airway or based on the assumption that the ventilation network of a mining section can be approximately represented by a single intake and a single return. The complexity of most models of the convection/diffusion type and the mobility aspect of diesel haulage units made a detailed emissions model very difficult to develop.The current model is an attempt to fill the need for a more generic tool applicable to mining sections employing multiple mobile diesel units by simplifying the convection-diffusion model to a convection-only model. The simplification is based on the fact that the diffusion coefficient will affect only the transient environmental contaminant concentrations with little or no affect on the time-weighted-average concentrations over a relatively long period such as a working shift (Lee et al., 1994). In view of the difficulties involved in mathematical modeling, the approach here is developing and using a computer simulation model. A PC-based FORTRAN 77 simulation model for the analysis of mining systems with multiple diesel sources and any ventilation network configuration was developed to study the distribution/transport of DPM in mine airways, evaluate methods of reducing DPM concentrations, and explore modifications to existing mining practice."

Dec 1, 1996

By Christopher C. Jobes, N. Kumar Kittusamy, Alan G. Mayton, Dean H. Ambrose

Researchers with the National Institute for Occupational Safety and Health (NIOSH) conducted a systematic study to evaluate seat designs on low- and mid-coal-seam shuttle cars. The purpose was to gather additional data to support earlier findings that NIOSH seats, with unique viscoelastic foam padding, are indeed improved designs for coal mine shuttle cars. This study included a larger sample of shuttle car operators than a prior NIOSH investigation. Eight shuttle car operators participated in evaluating seat designs on the basis of perceived levels of vehicle jarring/jolting and discomfort. Researchers then compared the operators’ perceptions with field-measured levels of vehicle jarring/jolting. Seven seat designs were evaluated on low- and mid-coal-seam shuttle cars during production operations at two underground coal mines in southern West Virginia. These seat designs comprised the one already in use on each vehicle and five NIOSH designs. Experimental data were collected using accelerometers, signal conditioning amplifiers, and filters connected to a data recorder, whereas subjective data were gathered via a visual analog scale (VAS) and a questionnaire. Field trials included shuttle cars operating under full- and no-load conditions. VAS responses indicated that NIOSH-designed seats performed better relative to comfort and isolation from vehicle jarring/jolting than the existing seats used in the shuttle cars. Both mid- and low-coal-seam shuttle car operators, during no-load and full-load conditions, rated lower levels of jarring/jolting with the NIOSH seat design. Questionnaire responses indicated that shuttle car operators rated NIOSH seat designs as more comfortable. Vehicle operators most frequently suggested the addition of armrests as a way to improve the seats on the mid-seam shuttle car. The quantitative levels of vehicle jarring/jolting for the no-load condition (more severe condition for vehicle operation) showed that NIOSH seats for the mid-coal-seam shuttle car performed better than the existing seat in terms of peak acceleration and crest factor. Similarly, for the low-coal-seam shuttle car, NIOSH seats performed better than the existing seat in terms of peak acceleration, root-mean-square (RMS) acceleration, and crest factor.

Jan 11, 2006

Determine the minimum waterflow rate needed for effective control of dust produced by cutting machines used to mine water-soluble ores. Approach Conventional wet-bar cutting techniques were studied to evaluate their dust control performance, and the optimum water flow needed for dust suppression was determined. Wet-bar type cutting techniques are used to help control mine dust by keeping the cutting chain wet. As the chain cuts the kerf, it dampens the dust produced by the cutting action at the point of generation. The Bureau, under contract, evaluated three basic wet-bar techniques, as shown in the diagram: water-trickle system A uses a gravity-feed or low-pressure (less than 50 psi) pump to send water through the bar and to discharge it at the bar tip. Water-spray system B uses a low-pressure spray nozzle located at the front of the cutter head. For protection the nozzle can be located within the cutter

Jan 1, 1982

By Alan H. Goode

The advancement of high-temperature drilling fluid technology for application in geothermal environments is part of the Bureau of Mines program for more efficient development of our Nation's energy resources. The bentonite constituent of water-base drilling fluids is sensitive to destabilization by high-temperature and salinity. A substitute material for bentonite, phosphate slime, which is reported to be saline resistant, was considered. These studies show that spray-dried slime suspensions have more favorable rheological behavior, but poorer filtration properties, as compared with bentonite suspensions.

Jan 1, 1975

By T. E. Green

The Bureau of Mines Heavy Metals Program emphasizes the need for improved analytical methods for gold determination. A commercially available ion exchange resin with high selectivity for gold was investigated as a potential method to collect gold from solution. The resin was found to quantitatively collect gold from acid solutions over a wide range of acid concentrations. Common metals were not collected by the resin nor did they seriously interfere with the collection of gold. X-ray spectrographic and neutron activation methods based on the use of papers containing this resin are proposed.

Jan 1, 1970

By R. W. Van Dolah

The feasibility of formulating cap-sensitive slurry explosives for use in underground mines with potentially flammable gas atmospheres was examined. Formulations containing aluminum metal as sensitizer and sodium chloride to reduce incendivity were prepared; some were cap-sensitive and had adequate air-gap. Flaked aluminum metal rather than the atomized type proved to be the more effective sensitizing agent of the formulations tested for incendivity in the large gallery of the Bureau of Mines, some were found to be suitably nonincendive.

Jan 1, 1968

By H. B. Cooke

In connection with its researches on the crude petroleums of the United States, the Bureau of Mines has made a particular study of apparatus for the distillation of hydrocarbon mixtures. While this study is still incomplete it has already resulted in the development of considerable laboratory and semi-plant equipment, motet of which has been described in various publications of the Bureau. The laboratory apparatus (Hempel distillation) and method gives satisfactory comparative results in the laboratory examination of crudes and have been found applicable to crudes of all types, but the agreement of laboratory and plant distillations is not as close as might be desired. This is due, in part, to limitations in size and construction of the laboratory apparatus. Some refiners claim that the Bureau of Mines' laboratory method (Hempel distillation3) for distilling crude petroleum, does not show the full gasoline content of the oil, while others have stated that it indicates more gasoline than can be obtained from the crude commercially. This difference of opinion among refiners results largely from the great variation in stills used and methods of operating them. The Bureau's experience has shown that crude oils from different fields vary widely in character; in fact, that it is not yet possible to classify crude's adequately on the basis of their Down chemical and physical characteristics. As a result of the differences that exist among crudes, and of the difficulty of designing refinery equipment, no standard practice has yet been adopted for the commercial distillation of petroleum, and ma" types of stills are used in the refineries of this country. Although many factors enter into the design of equipment and the development of commercial practice in refining of crude oil, there

Jan 1, 1924

Locating subsurface conductive solutions is important for many applications, including in situ mining and environmental protection. Drilling boreholes for sampling is expensive and can increase contamination by mixing water from different aquifers. Various noninvasive geophysical methods are available, but previous comparisons were hampered by different methods being used at different sites or at different times. The U.S. Bureau of Mines (USBM) compared methods at one site using the same conductive solution to improve the reliability of the comparisons. Locating deep (> 100 m) solutions is most difficult, SO the USBM selected methods applicable for such depths. Objective Improve the ability to locate subsurface conductive solutions by evaluating and comparing applicable geophysical methods. Approach The experiment was performed cooperatively with other agencies to increase the number of methods studied. The USBM, the University of Arizona, Sandia National Laboratories, and Zonge Engineering and Research, Inc., conducted cooperative field tests of six electromagnetic (EM) geophysical methods to compare their effectiveness in detecting salt water brine of conductivity 3.6 S/m collecting at the water table, 157 m subsurface. The brine was injected through two boreholes. The test site was the University's San Xavier experimental mine near Tucson, AZ. Geophysical surveys using surface and surface-borehole, time-domain electromagnetics (TEM); surface controlled-source audiofrequency magnetotellurics (CSAMT); surface magnetic field ellipticity, surface-borehole, frequency-domain electromagnetics (FEM); and crosshole FEM were conducted before and during brine injection. A total of 110,000 I. of brine was injected over one week, but the effective target volume of brine was much smaller because of mixing with ground water and dispersion.

Jan 1, 1994

By D. B. Taliaferro

An accurate knowledge of the water content of oil-bearing sands4/ now is recognized as an important factor in calculations of the flow of oil through the sands to producing wells and in the estimation of oil reserves, To this end the Bureau of Mines laboratories are using a method that is an adaptation of the A. S. T. M. method of determining the water content of petroleum products (1).5/ However, the apparatus and technique have been altered slightly, as described in this report, to increase the precision of the method without affecting the simplicity of procedure or speed with which determinations may be made. Until recently petroleum engineers, when estimating reserves assumed that the entire pore volume of the oil-saturated parts of producing sands was filled with oil, as it was generally thought that the oil, water, and gas in any formation had separated completely during geologic time into distinct layers because of their difference in density. In 1929 Lindthrop and Nickolaeff (12) reported experimental results from which they concluded that 22 to 30 percent of the pore volume of producing sands in the Grozay district, Russia, was filled with water when the fields were discovered. Since that time numerous investigators (5, 7, 8, 10) have found evidence of water in the sands of now oil-producing fields and old fields that never produced water with the oil.

Jan 1, 1940

By C. K. Rose

A hydraulic scaling rig was placed in operation at the Bureau of Mines oil-shale mine near Rifle, Colo., in 1953. The rig consists of a self-leveling platform mounted on a hydraulic-powered boom. The boom is mounted on the bed of a diesel truck. The equipment provides a movable work platform from which two men can work in safety and comfort while barring loose rock from the backs and walls of the rooms, pillars, and haulageways. INTRODUCTION As a part of its synthetic liquid fuels program the Bureau of Mines has developed a mine in the richer oil-shale beds of the Green River formation near Rifle, Colo. An important part of the work of the Oil-Shale Mining Branch is investigation of techniques for low-cost mining of oil shale on a commercial basis. It is evident that scaling loose rock from the high backs and walls of the mine represents a portion of the direct mining cost. This paper describes the development of a scaling rig for operation in the upper heading of the mine, which is 39 feet high.

Jan 1, 1954