Recirculating ventilation in the presence of gas emission source and internal air leaks in operating space

The model of mixed gas and air flow in the system of mine roadways which generate a recirculation loop is constructed. The model includes air leaks in the system. The gas distribution patterns in the recirculation loop are analyzed with regard to fresh air flow rates, recirculation ratios, as well as the values of air leaks and gas emission in the operating space. The variants of the desired ventilation quality due to increased supply of fresh air and owing to recirculating ventilation are discussed. On this basis, an approach is proposed to calculating the required fresh air to be supplied by the all-mine ventilation depending on recirculation ratios and air leaks. It is found that recirculating ventilation efficiency by the criterion of gas content of face area air depends on the air leaks. With the higher air leaks, the recirculating ventilation is more effective. The potential reduction in fresh air supply is calculated using the actual leakage factors typical of modern copper–nickel and potassium mines in Russia. The air demand calculation guidance for operating areas with recirculating ventilation is proposed. The traditional and proposed approaches to recirculating ventilation are compared.

Zaitsev A. V., Trushkova N. A. Recirculating ventilation in the presence of gas emission source and internal air leaks in operating space. MIAB. Mining Inf. Anal. Bull. 2022;(3):34-46. [In Russ]. DOI: 10.25018/0236_1493_2022_3_0_34.

The study was supported by the Russian Foundation for Basic Research, Project No. 20-45-596021, and by the Ministry of Science and Higher Education of the Russian Federation, State Contract No. 075-03-2021-374 dated 29 December 2020.

A.V. Zaitsev¹, Dr. Sci. (Eng.), Head of Sector, e-mail: aerolog_artem@gmail.com,
N.A. Trushkova¹, Leading Engineer, e-mail: aero.nadezhda@gmail.com,
¹ Perm Federal Research Center of the Ural Branch of Russian Academy of Sciences (PFRC UB RAS), Mining Institute of Ural Branch, RAS, 614007, Perm, Russia.

N.A. Trushkova, e-mail: aero.nadezhda@gmail.com.

1. Pravila bezopasnosti pri vedenii gornykh rabot i pererabotke tverdykh poleznykh iskopaemykh. Prikaz Rostekhnadzora № 505 ot 8.12.2020 [Safety rules for mining and processing of solid minerals. Rostechnadzor Order No. 505 dated 8.12.2020]. [In Russ].

2. Hall A. E., McHaina D. M., Hardcastle S. Controlled recirculation in Canadian underground potash mines. Mining Science and Technology. 1990, vol. 10, no. 3, pp. 305—314.

3. Pritchard C. J., Scott D. F. Examination of controlled recirculation implementation in an underground nonmetal mine. Mining Engineering. 2014, vol. 66, no. 12.

4. Pritchard C., Scott D., Frey G. Case study of controlled recirculation at a Wyoming trona mine. Transactions of Society for Mining, Metallurgy, and Exploration, Inc. 2013, vol. 334, no. 1, pp. 444—448.

5. Kruglov Yu. V. Teoreticheskie i tekhnologicheskie osnovy postroeniya sistem optimal'nogo upravleniya provetrivaniem podzemnykh rudnikov [Theoretical and technological foundations for building optimal control systems for ventilation of underground mines], Doctor’s thesis, Perm, 2012, 341 p.

6. Mokhirev N. N., Rad'ko V. V. Inzhenernye raschety ventilyatsii shakht. Stroitel'stvo. Rekonstruktsiya. Ekspluatatsiya [Engineering calculations of mine ventilation. Construction. Reconstruction. Exploitation], Moscow, Nedra-Biznestsentr, 2007, 327 p.

7. Kazakov B. P., Levin L. Yu., Shalimov A. V. Improving the efficiency of resource-saving ventilation systems for underground mines. Gornyi Zhurnal. 2014, no. 5, pp. 26—28. [In Russ].

8. Kazakov B. P., Isaevich A. G., Shalimov A. V. Ventilation of potash mines with partial reuse of air. Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal. 2007, no. 4, pp. 47—52. [In Russ].

9. De Souza E. Improving the energy efficiency of mine fan assemblages. Applied Thermal Engineering. 2015, vol. 90, рp. 1092–1097.

10. Butterworth M. Controlled recirculation in deep South African gold mines. CSIR Mining Technology, Johannesburg, South Africa. Proceedings of the 8th US Mine Ventilation Symposium. 1999, рp. 667–704.

11. Medvedev I. I., Krasnoshteyn A. E. Aerologiya kaliynykh rudnikov [Aerology of potash mines], Sverdlovsk, 1990, 252 p.

12. Flores V., Arauso L., Jara J., Raymundo C. Optimized ventilation model to improve operations in polymetallic mines in Peru. Proceedings of the 4th Brazilian Technology Symposium (BTSym’18). 2019, pp. 515—522.

13. Yu J., Li Z., Wang W. Influence of gas outburst dynamic flow on mine ventilation system. AIP Advances. 2021, vol. 11, no. 7, article 075223. DOI: 10.1063/5.0052080.

14. Patankar S. V. Numerical heat transfer and fluid flow. CRC press, 2018.

15. Krasnoshtein A. E., Kazakov B. P., Shalimov A. V. Modeling non-stationary gas admixture flow in excavations under recirculating airing. Journal of Mining Science. 2006, vol. 42, no. 1, pp. 85—90.

16. Krasnoshteyn A. E., Faynburg G. Z. Diffuzionno-setevye metody rascheta provetrivaniya shakht i rudnikov [Diffusion-network methods for calculating ventilation of mines and mines], Ekaterinburg, 1992, 243 p.

17. Saindon J.-P. Controlled recirculation of exhaust ventilation in Canadian Mines. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Applied Science. The University of British Columbia, 1987. 177 p.

18. Trushkova N. A. Study of the gas composition of the air to assess the possibility of using recirculation ventilation. Gornoe ekho. 2019, vol. 76, no. 3, pp. 84—87. [In Russ].

19. Shalimov A. V. Teoreticheskie osnovy prognozirovaniya, profilaktiki i bor'by s avariynymi narusheniyami provetrivaniya rudnikov [Theoretical foundations of forecasting, prevention and fight against emergency disruptions in mine ventilation], Doctor’s thesis, Perm, 2012, 329 p.

20. Zaytsev A. V. Nauchnye osnovy rascheta i upravleniya teplovym rezhimom podzemnykh rudnikov [Scientific basis for calculating and controlling the thermal regime of underground mines], Doctor’s thesis, Perm, 2019, 250 p.

21. Kazakov B. P., Grishin E. L., Trushkova N. A. Stability of joint operation of recirculating fans in underground potash mines. MIAB. Mining Inf. Anal. Bull. 2021, no. 2, pp. 108–119. [In Russ]. DOI: 10.25018/0236-1493-2021-2-0-108-119.

22. Kazakov B. P., Trushkova N. A., Zaytsev A. V. Partial air reuse to reduce moisture loss in potash mines. Vestnik Permskogo natsional'nogo issledovatel'skogo politekhnicheskogo universiteta. Geologiya. Neftegazovoe i gornoe delo. 2012, vol. 11, no. 3, pp. 129—133. [In Russ].

23. McPherson M. J. Subsurface ventilation and Environmental engineering. Chapman & Hall, 2009. 824 p.

24. Zhou A., Wang K., Wang J., Feng T. The role of methane buoyancy on the stability of airway airflow in underground coal mine ventilation. Journal of Loss Prevention in the Process Industries. 2018, vol. 54, pp. 346—351.