A proper borehole pattern design for coal seam methane drainage in Tabas coal mine using Comsol Multiphysics

Ali Bagherzadeh, M.Sc. graduated in mining exploitation, Department of Mining and Metallurgical Eng., Yazd University, Yazd, Iran
Mehdi Najafi, Department of Mining and Metallurgical Eng., Yazd University, SafayiehFollow
Mohammad Fatehi Marji, Professor, Department of Mining and Metallurgical Eng., Yazd University, Yazd, Iran
Mehdi Noroozi, Assistant Professor, Faculty of Mining, Petroleum and Geophysics Engineering, Shahrood University of Technology, Iran

Author ORCID Identifier

Mehdi Najafi 0000-0002-1609-3702

Mohammad Fatehi Marji 0000-0003-2917-6264

Mehdi Noroozi 0000-0001-6206-8121

Abstract

Optimizing the operational parameters of the borehole pattern in the coal seam includes the maximum amount of gas to be drained with the least amount of drilling, investment, and drainage time. The main purpose of this research is to properly design the drainage borehole pattern in the C1 coal seam of the Tabas coal mine. In this research, the Comsol Multiphysics software was used for numerical modeling of the boreholes. According to the method of diffusion of methane gas in a coal seam, the reduction of methane gas concentration and the amount of gas released from the coal blocks were approximated. For the gas drainage boreholes, the three patterns of the rectangular, parallelogram, and triangular forms were considered. Also, the boreholes were modeled with the three diameters of 76, 86, and 96 mm. This modeling was performed for 180 days of drainage operation and showed that the triangular pattern was more suitable than the other two patterns. The presented model is applicable in coal mines where gas drainage operations are necessary and helps engineers design the patterns of drainage boreholes to maximize their gas drainage efficiency.

Recommended Citation

Bagherzadeh, Ali; Najafi, Mehdi; Marji, Mohammad Fatehi; and Noroozi, Mehdi (2022) "A proper borehole pattern design for coal seam methane drainage in Tabas coal mine using Comsol Multiphysics," Journal of Sustainable Mining: Vol. 21 : Iss. 1 , Article 5.
Available at: https://doi.org/10.46873/2300-3960.1347