Mining Institute, Ural Branch, Russian Academy of Sciences, Perm, Russia:

E. L. Grishin, Head of Sector, Associate Professor, Candidate of Engineering Sciences, aeroevg@mail.ru
D. A. Borodavkin, Junior Researcher

Belaruskali JSC, Soligorsk, Belarus:
A. B. Petrovsky, Deputy Chief Engineer of Mining
A. S. Dolgikh, Chief Engineer at Mine Management 3

The article describes the large-scale studies on harmful factors which govern design values of fresh air amount for operational space. The gas content and temperature analyses allowed adjustment of the design approaches to the required air flow rates, microclimate control and partial air recycling. It is shown that relative gas content value in some operational spaces at Starobin deposit varies within wide ranges, and is independent of mining depth, gas content, location of operational spaces relative to the deposit boundary, and other geological and geotechnical factors. The values of air flow rates calculated for operational spaces from relative gas contents are lower than the currently adopted values for the gas content calculation in potassium strata. It is proved that, if necessary, it is possible to increase air recycling volume in mine ventilation system by using the value of relative gas content in operational spaces in the calculations. The formulas of temperature of air fed in an operational space are adjusted with regard to geothermometry. It is demonstrated that rock mass temperature depends both on the depth of mining and on the other coordinates. The temperature maps are developed for all potassium strata being mined. The formula of the air quantity required for the face area ventilation is adjusted with respect to the air temperature criterion and with regard to assimilation of heat emission by electric equipment. The criterion value of air temperature in longwalls is increased from 27.5 °С to 32 °С. This air temperature in combination with humidity not higher than 60 % ensures elimination of heat hazard in working environment.
The study was supported by Belaruskali JSC and by the Ministry of Science and Higher Education of the Russian Federation, R&D Project No. 122012000396-6.

1. Zaytsev A. V., Borodavkin D. A., Bublik S. A., Ageeva K. M. Study of rock temperature distribution in the Berezovsky mine field of Belaruskali Company. Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov. 2022. Vol. 333, No. 7. pp. 76–85.
2. Industrial Safety Regulations for Underground Mining of Salt Deposits in the Republic of Belarus : Approved by the Ministry of Emergency Situations of the Republic of Belarus, Decree No. 45 dated 30 August 2012. Available at: https://gospromnadzor.mchs.gov.by/upload/iblock/940/13.-pravila-po-obespecheniyu-promyshlennoy-bezopasnosti-prirazrabotke-podzemnym-sposobom-solyanykh-mestorozhdeniy-respubliki-belarus.pdf
(accessed: 15.06.2023).
3. Levin L. Yu., Zaitsev A. V. Simulation, Design, and Control of the Thermal Regime of Deep Mines. Doklady Earth Sciences. 2022. Vol. 507, Iss. 2. pp. 1160–1168.
4. Roy S., Mishra D. P., Bhattacharjee R. M., Agrawal H. Heat Stress in Underground Mines and its Control Measures: A Systematic Literature Review and Retrospective Analysis. Mining, Metallurgy & Exploration. 2022. Vol. 39, Iss. 2. pp. 357–383.
5. Dingyi Wei, Cuifeng Du, Yifan Lin, Baomeng Chang, Yuan Wang. Thermal environment assessment of deep mine based on analytic hierarchy process and fuzzy comprehensive evaluation. Case Studies in Thermal Engineering. 2020. Vol. 19. 100618. DOI: 10.1016/j.csite.2020.100618
6. Air quant ity design guidelines for mine ventilation at Starobin potash deposit. Minsk – Soligorsk – Perm, 2018.
7. Temporal guides on air quantity design for mine ventilation. Moscow, 1983. 71 p.
8. Semin M., Isaevich A. Analysis of Methane–Air Mixture Dynamics in a Dead-End Drift Ventilated Using an Exhaust System. Computation. 2022. Vol. 10, Iss. 12. 212. DOI: 10.3390/computation10120212
9. Andreyko S. S., Litvinovskaya N., Papulov A., Lyalina T. The Static Analysis of the Gas Content and the Gas-Dynamic Characteristics at the Second Potash Bed in the Starobinsk Potassium Salts Deposit. Fluids. 2022. Vol. 7, No. 8. 278. DOI: 10.3390/fluids7080278
10. Zaitsev A. V., Trushkova N. A. Recirculating ventilation in the presence of gas emission source and internal air leaks in operating space. GIAB. 2022. No. 3. pp. 34–46.
11. Isaevich A. G., Starikov A. N., Maltsev S. V. Improvement of air sampling method to determine relative concentration of combustion gases in mine air. GIAB. 2021. No. 4. pp. 143–153.
12. Sanitary Rules and Regulations : Hygienic Rating of Working Environment : Approved by the Ministry of Health of the Republic of Belarus, Decree No. 211 dated 28 December 2012. Available at: https://pravo.by/document/?guid=12551&p0=W21326895p (accessed: 15.06.2023).
13. Borodavkin D. A., Zaytsev A. V., Parshakov O. S., Khokhryakov D. S. Experimental study of working conditions of underground workers in the heating microclimate of a deep polymetallic mine. Bezopasnost truda v promyshlennosti. 2023. No. 2. pp. 69–75.