Abylkas Saginov Karaganda Technical University, Karaganda, Kazakhstan:

M. S. Usenbekov, Associate Professor, Candidate of Engineering Sciences, meirambek1946@mail.ru
T. K. Isabek, Professor, Doctor of Engineering Sciences, Academician of the Kazakh National Academy of Natural Sciences and of the National Academy of Mining Sciences of the Republic of Kazakhstan

Ualikhanov Kokshetau University, Kokshetau, Kazakhstan:
S. B. Zhaparova, Sadvakasov Agrotechnical Institute Director, Associate Professor, Candidate of Engineering Sciences

National Academy of Mining Sciences of the Republic of Kazakhstan, Astana, Kazakhstan:

Zh. T. Alpysbaeva, Researcher, PhD, Candidate of Biological Sciences

The occurrence conditions of coal seams in the Karaganda Coal Basin feature mostly complex geodynamics and gas dynamics. The local mines combat high-rate gas emission and coal and gas outbursts. Prevention of hazardous events of gas dynamics uses various techniques. The most effective prevention technique in case of coal and gas outbursts includes relaxation of coal seams from stresses and gas drainage during advanced cutting of neighbor protective seams. Efficiency of this approach depends on the protective seam parameters (thickness, spacing of the protected and protective seams, composition and properties of rocks in this parting, roof control method). As the depth of underground coal mining grows, the absolute and relative values of methane emission in mined-out voids increase. This study reviews some hypotheses and expert opinions which differently explain the mechanism of outgassing in closely spaced coal seams. On that basis, the objective was set to analyze gas release dynamics in mined-out void from closely spaced coal seams and from their partings, along cracks in highly gassy coal mining in the Karaganda Basin. To that end and for defining efficiency of gas drainage methods and flow charts, in-situ tests were carried out in six longwalls in three mines of ArcelorMittal Temirtau. The research findings and the conclusions made are recommended for the mining safety assessment in the similar conditions of geodynamics and gas dynamics, as well as for the development of practical measures for gas emission reduction and control in mining highly gassy and outburst-hazardous coal seams.

1. Aliev S. B., Khodzhaev R. R., Isabek T. K., Demin V. F., Shontaev A. Zh. Efficiency assessment of relief hole drilling in areas of high stresses to release methane from coal beds. Ugol. 2020. No. 11. pp. 10–12.
2. Isabek T. K., Demin V. F., Shontaev D. S., Malybaev S. K., Shontaev A. D. et al. Effective technology for drilling advance methane drainage boreholes in outburst-prone coal beds. Ugol. 2021. No. 6. pp. 11–14.
3. Isabek T. K., Khuangan N., Aytpaeva A. R., Shayverdenova R. T. Modeling the outburst state of an array with disjunctive disruption and mining using the finite element method. Ugol. 2020. No. 6. pp. 55–61.
4. Usenbekov M. S., Sadchikov V. A., Novikov V. Ya. Methane emission control in mines in the Karaganda Coal Basin. Karaganda : MChS RK, KarNIIPB, 2014. 273 p.
5. Usenbekov M. S., Isabek T. K., Polchin A. I., Zhumabekova A. E. Methane emission dynamics in mining in zones of geological faults. GIAB. 2022. No. 12. pp. 141–151.
6. Malinnikova O. N., Ulyanova E. V., Kharchenko A. V., Pashichev B. N. Influence of Coal Microstructure on Gas Content of the Face Area. Journal of Mining Science. 2020. Vol. 56, Iss. 3. pp. 351–358.
7. Radchenko S. A., Matvienko N. G. Methods of Fast Assessment of Intensity for Methane Release from Coal and Rocks to Improve Safety. Bezopasnost truda v promyshlennosti. 2014. No. 4. pp. 34–39.
8. Antoshchenko N. I., Okalelov V. N., Kulakova S. I. Influence of longwall advance rate on gas emission from undermined coal seams. Ugol Ukrainy. 2012. No. 2. pp. 5–8.
9. Antoshchenko N. I., Kulakova S. I. Physical and mathematical model of the dynamics of methane release from undermined coal seams. Gornyi Zhurnal. 2012. No. 8. pp. 89–93.
10. Zongqing Tang, Shengqiang Yang, Cheng Zhai, Qin Xu. Coal pores and fracture development during CBM drainage: Their promoting effects on the propensity for coal and gas outbursts. Journal of Natural Gas Science and Engineering. 2018. Vol. 51. pp. 9–17.
11. Zhang Li, Zhang Hui, Guo Hao. A case study of gas drainage to low permeability coal seam. International Journal of Mining Science and Technology. 2017. Vol. 27, Iss. 4. pp. 687–692.
12. Geng Jiabo, Xu Jiang, Nie Wen, Peng Shoujian, Zhang Chao lin et al. Regression analysis of major parameters affecting the intensity of coal and gas outbursts in laboratory. International Journal of Mining Science and Technology. 2017. Vol. 27, Iss. 2. pp. 327–332.
13. Cheng Cheng , Xiaoyu Cheng, Rui Yu, Wenping Yue, Chao Liu. The Law of Fracture Evolution of Overlying Strata and Gas Emission in Goaf under the Influence of Mining. Geofluids. 2021. Vol. 2021. ID 2752582. DOI: 10.1155/2021/2752582
14. Hongbing Wang, Zhiheng Cheng, Tie Li, Liang Chen, Quanle Zou et al. Evolution Characteristics of a High-Level Asymmetric Fracture-Seepage Community and Precise Coalbed Methane Drainage Technology during Mining of Outburst-Prone Coal Seam Groups. Shock and Vibration. 2021. Vol. 2021. ID 5537909. DOI: 10.1155/2021/5537909
15. Enyuan Wang, Peng Chen, Zhentang Liu, Yongjie Liu, Zhonghui Li et al. Fine detection technology of gas outburst area based on direct current method in Zhuxianzhuang Coal Mine, China. Safety Science. 2019. Vol. 115. pp. 12–18.