A Field Study of Longwall Mine Ventilation Using Tracer Gas in a Trona Mine
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A ventilation research study was conducted by the National Institute for Occupational Safety and Health and a cooperating trona mine in the Green River basin of Wyoming, USA. The mine operation uses the longwall mining method in trona bed 17, a commonly mined unit in the region. The longwall face length is 228 m (750 ft), and caving on the face occurred up to the back of the longwall shields. The mine is ventilated using a main blowing fan and a bleeder shaft. For this study, sulfur hexafluoride (SF6) tracer gas was released in two separate monitoring experiments. For the first experiment, tracer gas was released on the face, this test focused on airflow along the longwall face of the active panel. Face test showed the airflow patterns to be more complex than just head-to-tail flow in the main ventilation air stream on the active panel. For the second experiment, tracer gas was released 2 crosscuts inby the face on the headgate side, this test focused on gas transport in the mined-out portion of the same active panel. Gob test showed a pathway of movement through the front of the active panel gob that moved outby from the tailgate corner. The primary pathway of tracer gas movement in the active panel gob was towards the headgate and tailgate bleeders and out of a bleeder shaft. The rate of movement towards the back of the gob was measured to be 0.19 m/s (37 fpm).
KeywordsMine ventilation Longwall mining Trona Tracer gas
The authors recognize the essential contributions of others in the completion of this work. Cynthia Hollerich, James Addis, and Thomas Dubaniewicz are all critical contributors to the completion of this research effort. The authors also recognize the mine operator and numerous staff and management who were very important to the execution of our cooperative research effort.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
The findings and conclusions in this paper are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention. Mention of any company or product does not constitute endorsement by NIOSH.
- 1.Coal Age (2018) U.S. longwall census. Jan-Feb 2019 Issue, pages 24–28, https://coal.epubxp.com/i/1083177-jan-feb-2019 (Accessed April 2019)
- 2.Schatzel SJ, Krog RB, Dougherty H (2017) Methane emissions and airflow patterns on a longwall face: potential influences from longwall gob permeability distributions on a bleederless longwall panel. Trans Soc Min Metall Explor Inc 342(1):51–61Google Scholar
- 4.Schatzel SJ, Gangrade V, Hollerich CA, Addis JD, Chasko LL (2017) Tracer gas study to determine face ventilation air and gob gas movement patterns on a bleederless longwall panel. 2017 SME Annual Meeting and Exhibit, Denver, CO, February 19–22, 2017, Pre-print 17–137Google Scholar
- 5.Karacan CÖ, Yuan L (2015) Effect of discrete fracture network representation of gob on airflow distribution near the longwall face. In: Proceedings of the 15th North American Mine Ventilation Symposium, Blacksburg, VAGoogle Scholar
- 7.Gangrade V, Harteis SP, Addis JD (2017) Studying longwall ventilation with physical modeling. Coal Age 123(6, July–August 2018):38–39Google Scholar
- 8.Gangrade V, Harteis SP, Addis JD (2017) Development and applications of a scaled aerodynamic model for simulations of airflows in a longwall panel. In: proceedings of 16th North American Mine Ventilation Symposium. Golden, CO: Colorado School of Mines. Pp. 6–17–6-24Google Scholar
- 9.Thimons ED, Bielicki RJ, Kissel FN (1974) Using sulfur hexafluoride as a gaseous tracer to study ventilation systems in mines. US Department of the Interior, Bureau of Mines, Report of Investigation No. 7916, NTIS No. PB-234052. https://www.cdc.gov/niosh/mining/works/coversheet1500.html
- 10.Thimons ED, Kissell FN (1974) Tracer gas as an aid in mine ventilation analysis. US Department of the Interior, Bureau of Mines Investigations, No. 7917, NTIS No. PB234051, 17 pp.Google Scholar
- 11.Timko RJ, Thimons ED (1982) Sulfur hexafluoride as a mine ventilation research tool – recent field applications. US Department of the Interior, US Bureau of mines, Report of Investigations, No. 8735, NTIS No. PB83-171819, 15 pp.Google Scholar
- 12.Mucho TP, Diamond WP, Garcia F, Byars JD, Cario SL (2000) Implications of recent NIOSH tracer gas studies on bleeder and gob gas ventilation design. Society of Mining Engineers Annual Meeting, Feb. 28–Mar. 1, Salt Lake City, UTGoogle Scholar
- 13.Schatzel SJ, Krog RB, Dougherty H (2011) A field study of us longwall coal mine ventilation and bleeder performance. SME preprint 11–013. SME, LittletonGoogle Scholar
- 15.Singh AK, Ahmad I, Sahay N, Varma NK, Singh VK (2004) Air leakage through underground ventilation stoppings and in situ assessment of air leakage characteristics of remote filled cement concrete plug by tracer gas technique. J South Afr Inst Min Metall 104(2):101–106Google Scholar
- 16.Pandey JK, Varma NK, Singh AK, Gupta ML (1999) Development of SF6 tracer gas technique for measuring air flow rate. J Mines Met Fuels 47(11 SPEC. ISS., November 1999):289–291Google Scholar
- 17.Jong EC, Luxbacher KD, Karmis ME, Westman EC (2016) Field test of a perfluoromethylcyclohexane (PMCH) permeation plug release vessel (PPRV) in an underground longwall mine. Trans Inst Min Metall A: Min Technol 125(2):65–70Google Scholar
- 20.Self JG, Ryder RT, Johnson RC, Brownfield ME, Mercier TJ (2016) Stratigraphic cross sections of the Eocene Green River Formation in the Green River Basin, Southwestern Wyoming, Northwestern Colorado, and Northeastern, Utah, in US geological survey oil shale assessment team, oil shale resources of the Eocene Green River Formation, Greater Green River Basin, Wyoming, Colorado, and Utah. US geological survey digital data series, DDS-69-DDGoogle Scholar
- 21.Wiig SV, Grundy WD, Dyni JR (1995) Trona resources in the Green River Basin, Southwest Wyoming. US geological survey open file report 95–476, 88 pp.Google Scholar
- 22.Code of Federal Regulations (2011) Washington, DC, US government printing office, Office of the Federal RegisterGoogle Scholar
- 23.Pritchard C, Glackin B, Patton L, Refsdal L, Leigh RT (2004) Ventilation systems for underground Trona mines. 10th US/NA Mine Ventilation Symposium, Anchorage, AK, pp. 49–58Google Scholar
- 24.NIOSH (1994) Sulfur hexafluoride by portable GC, NIOSH method 6602. NIOSH manual of analytical methods, 2003–154, third supplement. http://www.cdc.gov/niosh/docs/2003-154/