Advertisement

Transport in Porous Media

, Volume 116, Issue 2, pp 847–868 | Cite as

Experimental Investigation on the Permeability Evolution of Compacted Broken Coal

  • Tingxiang ChuEmail author
  • Minggao Yu
  • Deyi Jiang
Article

Abstract

Given the importance of airflow seepage properties to coal self-oxidation in gob, this paper develops a method and self-designed apparatus to assess seepage properties of compacted broken coal. This study mainly focuses on the strain, porosity and permeability evolution under the different conditions of particle size, vertical stress and temperature. The studied results show: (1) The strain, porosity and permeability were enlarged when the particle size increased under the same loading stress. The porosity and permeability reduced when the vertical stress increased. (2) The non-Darcy coefficient was negative in all tests, but the absolute value of the non-Darcy coefficient generally increased when the vertical stress increased. (3) The experiment results indicated that the larger the particle was, the easier to be compacted. The larger the grain diameter was, the lower the porosity and permeability were, which shown that the void volume in broken coal with larger grain diameters could be easily compacted. (4) The permeability was reduced when the temperature increased, which indicated the permeability of the compacted broken coal decreased during low-temperature oxidation in gob. (5) By the effects of stress and the particle size diameter on the porosity and permeability, the vertical stress recovery and generally increase are advantageous to reduce the porosity and permeability in gob. It is favorable to reduce the porosity and permeability and prevent coal self-heating by reducing the degree of fragmentation and percentage of small particles or consolidate the small particles.

Keywords

Broken coal Gob Particle size Non-Darcy flow Compaction Seepage 

Notes

Acknowledgements

This work was supported by The National Natural Science Foundation of China (U1361205, 51404090, 51574111), The Scientific Research Foundation of State Key Lab. of Coal Mine Disaster Dynamics and Control (Nos. 2011DA105287-ZD201401).

References

  1. Adhikary, D., Guo, H.: Modelling of longwall mining-induced strata permeability change. Rock Mech. Rock Eng. 48, 345–359 (2015)CrossRefGoogle Scholar
  2. Bai, H., Ma, D., Chen, Z.: Mechanical behavior of groundwater seepage in Karst collapse pillars. Eng. Geol. 164, 101–106 (2013)CrossRefGoogle Scholar
  3. Blodgett, S., Kuipers, J.: Underground Hard-Rock Mining: Subsidence and Hydrologic Environmental Impacts. Centre of Science in Public Participation, Bozeman (2002)Google Scholar
  4. Ding, H., Miao, X., Ju, F., Wang, X., Wang, Q.: Strata behavior investigation for high-intensity mining in the water-rich coal seam. Int. J. Min. Sci. Technol. 24, 299–304 (2014)CrossRefGoogle Scholar
  5. Forster, I., Enever, J.: Hydrogeological response of overburden strata to underground mining. Off. Energy Rep. 1, 104 (1992)Google Scholar
  6. Galvin, J.: Surface subsidence mechanisms-theory and practice, part 2-practice. Coal J. 17, 11–25 (1987b)Google Scholar
  7. Galvin, J.: Surface subsidence mechanisms-theory and practice, part I-theory. Coal J. 16, 31–41 (1987a)Google Scholar
  8. Karacan, C.O.: Prediction of porosity and permeability of caved zone in longwall gobs. Transp. Porous Media 82, 413–439 (2010)CrossRefGoogle Scholar
  9. Kesseru, Z.: Empirical and theoretical methods for designing soft semi-permeable protective barriers. Int. J. Mine Water 3(2), 1–13 (1984)CrossRefGoogle Scholar
  10. Kuenzer, C., Stracher, G.B.: Geomorphology of coal seam fires. Geomorphology 138, 209–222 (2012)CrossRefGoogle Scholar
  11. Li, S., Miao, X., Chen, Z.: Nonlinear dynamic analysis on non-Darcy seepage in over-broken rock mass. J. China Coal Soc. 30, 557–561 (2005)Google Scholar
  12. Li, S., Miao, X., Chen, Z., Mao, X.: Experimental study on seepage properties of non-Darcy flow in confined broken rocks. Eng. Mech. 4, 85–92 (2008). (in Chinese)Google Scholar
  13. Liu, H., Rutqvist, J.: A new coal-permeability model: internal swelling stress and fracture–matrix interaction. Transp. Porous Media 82, 157–171 (2010)Google Scholar
  14. Liu, W.Q., Fei, X.D., Fang, J.N.: Rules for confidence intervals of permeability coefficients for water flow in over-broken rock mass. Int. J. Min. Sci. Technol. 22, 29–33 (2012)Google Scholar
  15. Ma, D., Miao, X., Jiang, G., Bai, H., Chen, Z.: An experimental investigation of permeability measurement of water flow in crushed rocks. Transp. Porous Media 105, 571–595 (2014)CrossRefGoogle Scholar
  16. Ma, D., Miao, X., Wu, Y., Bai, H., Wang, J., Rezania, M., Qian, H.: Seepage properties of crushed coal particles. J. Pet. Sci. Eng. 146, 297–307 (2016)CrossRefGoogle Scholar
  17. McKee, C.R., Bumb, A.C., Koenig, R.A.: Stress-dependent permeability and porosity of coal and other geologic formations. SPE Form. Eval. 3, 81–91 (1988)Google Scholar
  18. Meng, Z., Zhang, J., Wang, R.: In-situ stress, pore pressure and stress dependent permeability in the Southern Qinshui Basin. Int. J. Rock Mech. Min. Sci. 48, 122–131 (2011)CrossRefGoogle Scholar
  19. Meng, Z., Hou, Q.: Experimental research on stress sensitivity of coal reservoir and its influencing factors. J. China Coal Soc. 37, 430–437 (2012). (in Chinese)Google Scholar
  20. Miao, X., Li, S., Chen, Z., Liu, W.: Experimental study of seepage properties of broken sandstone under different porosities. Transp. Porous Media 86, 805–814 (2011)CrossRefGoogle Scholar
  21. Min, K., Rutqvist, J., Tsang, C., Jing, L.: Stress-dependent permeability of fractured rock masses: a numerical study. Int. J. Rock Mech. Min. Sci. 41, 1191–1210 (2004)Google Scholar
  22. Pappas, D., Mark, C.: Behavior of simulated longwall gob material. Report of investigations, US Bureau of Mines (1993)Google Scholar
  23. Schatzel, S., Karacan, C.O., Dougherty, H., Goodman, G.: An analysis of reservoir conditions and responses in longwall panel overburden during mining and its effect on gob gas well performance. Eng. Geol. 127, 65–74 (2012)CrossRefGoogle Scholar
  24. Singh, M., Kendorski, F.: Strata disturbance prediction for mining beneath surface water and waste impoundments. In: Proceedings of the First Conference on Ground Control in Mining, West Virginia University, pp. 76–89 (1981)Google Scholar
  25. Singh, R., Hibberd, S., Fawcett, R.J.: Studies in the prediction of water inflows to longwall mine workings. Int. J. Mine Water 5(3), 29–46 (1986)CrossRefGoogle Scholar
  26. Song, Z., Zhu, H., Jia, G., He, C.: Comprehensive evaluation on self-ignition risks of coal stockpiles using fuzzy AHP approaches. J. Loss Prev. Process Ind. 32, 78–94 (2014)CrossRefGoogle Scholar
  27. Taraba, B., Michalec, Z.: Effect of longwall face advance rate on spontaneous heating process in the gob area—CFD modelling. Fuel 90, 2790–2797 (2011)CrossRefGoogle Scholar
  28. Xia, T., Zhou, F., Liu, J., Kang, J., Gao, F.: A fully coupled hydro-thermo-mechanical model for the spontaneous combustion of underground coal seams. Fuel 125, 106–115 (2014)CrossRefGoogle Scholar
  29. Xia, T., Wang, X., Zhou, F., Kang, J., Gao, F.: Evolution of coal self-heating processes in longwall gob areas. Int. J. Heat Mass Transf. 5, 861–868 (2015)CrossRefGoogle Scholar
  30. Yuan, L., Smith, A.C.: Numerical study on effects of coal properties on spontaneous heating in longwall gob areas. Fuel 87, 3409–3419 (2008)CrossRefGoogle Scholar
  31. Zhang, J., Standifird, W., Roegiers, J., Zhang, Y.: Stress-dependent permeability in fractured media: from lab experiments to engineering applications. Rock Mech. Rock Eng. 40, 3–21 (2007)CrossRefGoogle Scholar
  32. Zhu, H., Song, Z., Tan, B., Hao, Y.: Numerical investigation and theoretical prediction of self-ignition characteristics of coarse coal stockpiles. J. Loss Prev. Process Ind. 26, 236–244 (2013)CrossRefGoogle Scholar
  33. Zimmerman, R.: Coupling in poroelasticity and thermoelasticity. Int. J. Rock Mech. Min. Sci. 37, 79–87 (2000)CrossRefGoogle Scholar
  34. Zimmerman, R., Bodvarsson, G.: Hydraulic conductivity of rock fractures. Transp. Porous Media 23, 1–30 (1996)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.State Key Laboratory of Coal Mine Disaster Dynamics and ControlChongqing UniversityChongqingPeople’s Republic of China
  2. 2.School of Safety Science and EngineeringHenan Polytechnic UniversityJiaozuoPeople’s Republic of China

Personalised recommendations