Results 71 - 80 of 83

• Determining the Source of Longwall Gob Gas: Lower Kittanning Coalbed, Cambria County, PA
  1/1/1992 - Reports of Investigations
  Four coreholes were drilled at a longwall mine in the Lower Kittanning coalbed to obtain coal and rock samples from overlying strata to determine their gas content during the mining cycle. Test results indicate that 91% of the gas came from coalbeds.
• Evaluating Ventilation Parameters of Three Coal Mine Gobs
  1/1/1986 - Information Circulars
  The Bureau of Mines used sulfur hexafluoride (sf6) tracer gas to evaluate the effectiveness of gob ventilation and/or sealing practices at three coal mines, each having different problems associated with their mined-out areas.
• Sulfur Hexafluoride as a Mine Ventilation Research Tool - Recent Field Applications
  12/1/1982 - Reports of Investigations
  Sulfur hexafluoride (SF6) is an odorless, colorless, nontoxic gas that has found acceptance as a tracer gas in research on ventilation patterns, measurement of air leak rates, respirable dust reductions due to bagging hood modifications, and the study o...
• Face Ventilation Measurement with Sulfur Hexafluoride (SF6)
  1/1/1980 - Reports of Investigations
  The face ventilation measurement method developed by the Bureau of Mines involves releasing a small volume of tracer gas (SF6) on the off-curtain side of the working face at the start of the mining cycle.
• Study of Mine Fires and Mine Ventilation: Part I, Computer Simulation of Ventilation Systems Under the Influence of Mine Fires
  9/1/1977 - Contract reports, Open File Reports
  An existing computer program for mine ventilation network is modified so that it can simulate ventilation conditions under the influence of mine fires. The resulting new program is designed for the practical ventilation engineer and should be applicable...
• Using Sulfur Hexafluoride as a Gaseous Tracer to Study Ventilation Systems in Mines
  1/1/1974 - Reports of Investigations
  The Bureau of Mines found sulfur hexafluoride (SF6), released from a lecture bottle, to be an ideal gaseous tracer for studying mine ventilation systems. In a Pennsylvania limestone mine, this technique was useful in evaluating the effectiveness of auxi...
• The Direct Method of Determining Methane Content of Coalbeds for Ventilation Design
  1/1/1973 - Reports of Investigations
  The applicability of the "direct method" for determining the methane content of virgin coalbeds was tested. Preliminary results indicate that the direct method, when applied to exploration cores, can be successfully used to estimate coalbed gas content ...
• Use of Vertical Boreholes for Assisting Ventilation of Longwall Gob Areas
  3/1/1969 - Technical Progress Reports
  An experimental degasification program using a vertical borehole and vacuum pump to drain gas from the gob area of a longwall panel was successful at Bethlehem Mines Corporation, Cambria Division, No. 33 coal mine. Sixty-one million cubic feet of methan...
• Introduction to Mine Ventilating Principles and Practices
  1/1/1960 - NIOSH/USBM numbered publications
  This bulletin is written to explain in layman language the basic laws and fundamentals of mine airflow and their application to the solution of common ventilating problems. The attempt is to reduce the complex and difficult ventilating formulas to simpl...
• MFIRE Users Manual Version 2.20
  8/1/1995 - Unpublished documents and reports
  MFIRE is a computer simulation program that performs normal ventilation network planning calculations, and dynamic transient state simulation of ventilation networks under a variety of conditions. This user manual describes the development of MFIRE, the...