Progress and development of coal mine gas explosion suppression and disaster reduction technology in China

Gas explosion seriously threatens the safety of coal mining. The prevention of gas explosion has always been one of the key points in the safety work of coal mine. Chinese relevant research institutions and scholars have carried out extensive studies in preventing and controlling gas explosion,and developed a series of gas explosion suppression and mitigation techniques and equipment. Based on the perspective of literature research,this paper reviewed the re- search status of China’s gas explosion suppression and disaster reduction technologies from fundamental research of gas explosion,material development,equipment research and development. For gas ex-plosion and suppression,the pa- rameters,such as maximum explosion pressure and maximum pressure rise rate,are mainly attained through employing experimental method,which are used to characterize the results of gas explosion that is motivated by obstacles or sup- pressed by the inhibitor. However,the detailed information about explosion and suppression process has not been fully understood. With the coupling effect of explosion flame,turbulence and pressure wave,the gas explosion flame propa- gation model still needs to be improved. The detained action mechanism of explosion suppression medium on gas explo- sion reaction during the gas explosion suppression process still needs to be clarified. For gas explosion suppression e- quipment,the (extremely) large gas explosion accidents in recent years indicate that the existing gas explosion sup- pression and control equipment are more difficult to accurately detect,quickly respond and effectively suppress the gas explosion flame,resulting in the techniques and equipments playing a limited role to prevent and control the gas explo- sion. Both the arrangement of gas explosion suppression and control equipment and the improvement of gas explosion suppression and control equipment’s efficiency still need to be further researched. For disaster reduction equipment, the scholars mainly consider to change the structure of blast proof-door to realize quick opening and resetting. In these designs,there is a lack of consideration of failure dynamic mechanical characteristics and action response characteris- tics of blast shaft doors under instantaneous ( millisecond) impact. In the future,the developing gas suppression and mitigation techniques and equipment systems should be based on the theory of gas explosion mechanism and flame propagation characteristics. The future study should break the research methods based on experiments,develop theoret- ical models of numerical simulation and study on basic theories. The future study should take gas explosion suppression media and explosion suppression mechanisms as the core to explore efficient composite explosion suppression materials with coupling mechanisms of physical and chemical suppression. With gas explosion suppression equipment and disas- ter mitigation technology as the guarantee,the future study should develop gas explosion flame detection technology that takes fast speed,high accuracy and stability into account,optimizes the configuration of each explosion suppression and explosion control equipment to research integrated intelligent air shaft explosion-proof door with anti-shock,multi- ple pressure relief,quick reset,lock seal and automatic control functions.