International Scientific Journal


High temperature nitrogen, injection into coal seams is supposed to improve the per­meability and thus maintain the safety of underground mining. A novel triaxial appa­ratus is recently developed, aiming at providing the effective method to evaluate the effect of high temperature nitrogen injection. The main feature of this novel appara­tus is its high confining pressure, gas injection with high pressure as well as the high temperature. This new device can be either used for natural coal samples (e.g. intact or fractured) or the synthetic coal samples. A series of leakage tests were conducted to verify the feasibility of this instrument, the results of which have confirmed that the maximum pressure (i.e. 10 MPa) can be reached. In addition, the high temperature and pressure of nitrogen gas can also be sustain at the requested level. Based on the preliminary tests on the instrument, a large amount of tests were carried out to eval­uate the effect of nitrogen injection in enhancing the permeability of coking coal from the Pingdingshan coalfield, China, and the influence of high temperature nitrogen injection on mechanical parameters of coal was obtained.
PAPER REVISED: 2021-07-25
PAPER ACCEPTED: 2021-08-10
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 6, PAGES [4527 - 4535]
  1. Yuan, L., Key Technique of Safe Mining in Low Permeability and Methane Rich Seam Group, Chinese Journal of Rock Mechanics and Engineering, 27 (2008), 6, pp. 1370-1379
  2. Qian, M., Consideration on the Development of China Coal in Industry, China Coal, 31 (2005), 9, pp. 5-9
  3. Wang, S., et al., A Heat Transfer Model of High-Temperature Nitrogen Injection into a Methane Drainage Borehole, Journal of Natural Gas Science and Engineering, 24 (2015), 7, pp. 449-456
  4. Zhou, F., Study on the Coexistence of Gas and Coal Spontaneous Combustion I: Disaster Mechanism, Journal of China Coal Society, 37 (2012), 5, pp. 843-849
  5. He, M., et al., Study on Rock Mechanics in Deep Mining Engineering, Chinese Journal of Rock Mechanics and Engineering, 24 (2005), 16, pp. 2803-2813
  6. Li, M., et al., Study on Deep Mining Safety Control Decision Making System, Procedia Earth and Planetary Science, 1 (2009), 1, pp. 377-383
  7. Zhou, H., et al., Developments in Researches on Mechanical Behaviors of Rocks under the Condition of High Ground Pressure in the Depths, Advances in Mechanics, 35 (2005),1, pp. 91-99
  8. Ranjith, P., et al., A New Triaxial Apparatus to Study the Mechanical and Fluid-Flow Aspects of Carbon Dioxide Sequestration in Geological Formations, Fuel, 90 (2011), 3, pp. 2751-2759
  9. Durucan, S., et al., Effects of Stress and Fracture on Permeability of Coal, Mining Science and Technology, 3 (1986), 3, pp. 205-216
  10. Gentzis, T., et al., Geomechanical Properties and Permeability of Coals from the Foothills and Mountain Regions of Western Canada, International Journal of Coal Geology, 69 (2007), 3, pp. 153-164
  11. McKee, C., et al., Stress-Dependent Permeability and Porosity of Coal and Other Geologic Formations, Spe Formation Evaluation, 3 (1988), 1, pp. 81-91
  12. Somerton W., et al., Effect of Stress on Permeability of Coal, International Journal of Rock Mechanics and Mining Science and Geomechanics Abstracts, 12 (1975), 5-6, pp. 129-145
  13. Viete, D., et al., The effect of CO2 on the Geomechanical and Permeability Behaviour of Brown Coal: Implications for Coal Seam CO2 Sequestration, International Journal of Coal Geology, 66 (2006), 3, pp. 204-216
  14. Barla, G., et al., New Triaxial Apparatus for Rocks, Rock Mechanics and Rock Engineering, 43 (2010), 2, pp. 225-230

© 2023 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence