Lessons Learned From Research About Methane Explosive Gas Zones in Coal Mine Gobs

Coal mine longwall gobs contain explosive methane gas zones (EGZs) that can cause mine fires and explosions when EGZs extend into active mining areas. The tragic explosion at the Upper Big Branch Mine in West Virginia in April 2010 cost 29 miners' lives and may have been caused by this mechanism. This paper summarises the significant research findings from five years of computational fluid dynamics (CFD) modelling research conducted at the Colorado School of Mines (CSM) under funding from the US National Institute for Occupational Safety and Health (NIOSH). CSM research has shown that EGZ formation can be effectively controlled by progressive sealing of the gob and injecting nitrogen where necessary.