Study on the Parameters of Collaborative Fire Prevention by Plugging Air Leakage with Isolation Wall and Injecting Nitrogen in the Goaf of Re-Mining Working Face

This study focuses on preventing coal spontaneous combustion in re-mining working face, using Yunhe Coal Mine as a case study. The investigation of spontaneous combustion characteristics in both new and re-mined coal samples revealed that the re-mined coal exhibits a higher oxygen consumption rate and greater heat release intensity compared to new mining coal. Through field observations and numerical simulations, the distribution range of oxidation zones in goaf within different zones of the re-mining working face was determined. Based on these findings, a collaborative fire prevention measure is proposed, involving plugging air leakage with isolation wall and injecting nitrogen into the goaf. The implementation of these fire prevention measures results in a reduction in the size of the oxidation zone, an increase in the size of the asphyxiation zone, and a decrease in the maximum temperature. To further enhance fire prevention efforts, it is recommended that distinct cooperative fire prevention parameters be established for both new mining zones and re-mining zones. These research findings provide a theoretical foundation for more efficient fire prevention measures in re-mining working face.