A Network Model Analysis of an Unconventional Gas Well Breach Above an Underground Coal Mine [2023]

Details

• Personal Author:
  Dougherty H ; Kimutis R ; Watkins E
• Description:
  Gas wells have often intersected mining resources, but unconventional shale well drilling has more recently challenged mines to balance the risk of interaction due to higher pressures and larger quantities of gas. Full extraction mining, such as the longwall method, induces ground movement that may influence the casings if wells are drilled within the mining area. The possibility of a casing shear would lead to the risk of unplanned gas migration into the mine. This has the potential to quickly overcome the ventilation system and reach the explosive range which, if ignited, can have catastrophic consequences on the health and safety of underground workers. The utilization of network software to model mine ventilation is a common practice in the mining industry as a predictive tool for planning and monitoring and can assist with a well breach scenario over a large mining area. This work focuses on a well breach in between two longwall panels after second panel mining with gas entering primarily through the gobs of the adjacent longwall panels. Applying the network software Ventsim, a gob zone and ventilation network were created to better understand the distribution of gas within the mine and the limitations and effectiveness of a ventilation system. The model shows both a transient flow simulation and steady state concentrations throughout the mine ventilation system. Using a standard Pittsburgh coal seam longwall ventilation scheme, we find that the system can dilute a significant inflow of up to 700 cfm of methane. [Description provided by NIOSH]
• Subjects:
  Coal Coal Mining Mining Occupational Health Safety Ventilation
• Keywords:
  Author Keywords: Coal Mine Coal Mining Computerized Simulation Explosion Prevention Explosive Gases Gas Flow Gas Well Breach Longwall Mining Methane Methane Control Mine Gases Network Model Analysis Underground Mines

  More +
• Series:
  Mining Publications
• ISSN:
  2524-3462
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PMRD - Pittsburgh Mining Research Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  40
• Issue:
  6
• NIOSHTIC Number:
  nn:20068641
• Citation:
  Min Metall Explor 2023 Dec; 40(6):2161-2166
• Email:
  hndoug@vt.edu
• CAS Registry Number:
  Methane (CAS RN 74-82-8)
• Federal Fiscal Year:
  2024
• NORA Priority Area:
  Mining ; Oil and Gas Extraction
• Peer Reviewed:
  True
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:7b039fe327b97daeba04759fc76f678e76257b547b469528fee18a68406e8aae913717870b17eb9bf5cb0c1c6edc5ab396b51fdc8a7dab31fef9b167de2e7a4d
• Download URL:
  https://stacks.cdc.gov/view/cdc/215660/cdc_215660_DS1.pdf
• File Type:
  [PDF - 1.24 MB ]