Saint-Petersburg Mining University, Saint-Petersburg, Russia:
V. P. Zubov, Head of Chair, Doctor of Engineering Sciences, spggi_zubov@mail.ru
D. G. Sokol, Mining Engineer

Currently mines of Belaruskali actively expand production capacities in the conditions of great depth of productive strata and high concentration of mining operations. High power loading of mining equipment in combination with complicated geotechnical conditions are the major causes of increased air temperatures in longwalls. In view of the intended social and technological improvement, one of the current tasks of the top priority is normalization of temperature conditions in longwalls pursuant to the effective standards. The data required for the set task solution were obtained during underground investigation of geotechnical situations which have influence on temperature of intake air currents in longwalls. This article presents the research findings on the formation of temperature conditions in longwall mining. At the great mining depths (500–600 m and more), the temperature of intake air currents exceeds the maximal allowable values. It is expedient to change to the specially designed pillarless mining flow charts capable to ensure independent ventilation of longwall and power train, and to enable heat transfer between intake air flow and rocks in mined-out areas.

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