Mining a coal seam below a heating goaf with a force auxiliary ventilation system at Longhua underground coal mine, China

Extraction of a coal seam which lies not far below a heating goaf can be a major safety challenge. A force auxiliary ventilation system was adopted as a control method in successful extraction and recovery of the panel 30110 of the #3−1 coal seam, which is about 30–40 m below the heating goaf of the #2−2 seam at Longhua underground coal mine, Shanxi Province, China. Booster fans and ventilation control devices such as doors and regulators were used in the system. The results show that, provided that a force auxiliary ventilation system is properly designed to achieve a pressure balance between a panel and its overlying goaf, the system can be used to extract a coal seam overlain by a heating goaf. This paper describes the design, installation and performance of the ventilation system during the extraction and recovery phases of the panel 30110.