Optimization of Gob Ventilation Boreholes Design in Longwall Mining

Details

• Personal Author:
  Brune, Jürgen F. ; Khan MU ; Saki SA
• Description:
  Gob ventilation boreholes (GVBs) are widely used for degasification in U.S. longwall coal mines. Depending on geological conditions, 30-50% of methane can be recovered from longwall gob using GVBs. A NIOSH funded research at the Colorado School of Mines confirmed that GVBs can efficiently reduce methane at the face. However, GVBs can also draw some fresh air from the face and create explosive gas zones (EGZs). Explosive gas mixtures may be formed in gob areas due to the increased ingress of oxygen from GVBs. It is critical to identify the locations for GVBs for maximizing extraction of methane and minimizing hazards of explosion. This study analyzes the effect of operating parameters and design of GVB on methane extraction, EGZs formation, and face and tailgate methane concentrations. Methane extraction, formation of EGZs, and concentration of methane in working areas are significantly impacted by various factors. These factors include the distance of work face and tailgate from GVBs, diameter of GVBs, vacuum pressure of wellhead, GVB distance from the roof of the coal seam, and number of operating GVBs in a panel. Computational fluid dynamics (CFD) evaluations suggest optimal design and operating parameters of GVBs that can contribute to maximum benefits with minimum risks. [Description provided by NIOSH]
• Subjects:
  Occupational Health Safety Ventilation
• Keywords:
  Author Keywords: Longwall Mining Boreholes Computational Fluid Dynamics Explosive Gases Explosive Gas Zones Gas Flow Gob Ventilation Boreholes Longwall Mining Methane Drainage
• ISSN:
  2095-2686
• Document Type:
  Text
• Funding:
  Contract
• Genre:
  Journal Article
• Place as Subject:
  Colorado ; OSHA Region 8
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  30
• Issue:
  6
• NIOSHTIC Number:
  nn:20068303
• Citation:
  Int J Min Sci Technol 2020 Nov; 30(6):811-817
• Contact Point Address:
  Saqib Ahmad Saki, University of Engineering and Technology Lahore, Lahore 54890, Pakistan
• Email:
  saqib.saki@fulbrightmail.org
• Federal Fiscal Year:
  2021
• Performing Organization:
  Colorado School of Mines
• Peer Reviewed:
  True
• Start Date:
  20090902
• Source Full Name:
  International Journal of Mining Science and Technology
• End Date:
  20140901
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:07dc5344a064fbd0f62fd5e6c5e5f8957f6eb7a20b9e9ff3a9fc2afb3bcfc616f2127c35f061b8bd4488e73aec3c58e7abf95ef86d984a62ad724d3e5fd33fbc
• Download URL:
  https://stacks.cdc.gov/view/cdc/230479/cdc_230479_DS1.pdf
• File Type:
  [PDF - 1.63 MB ]