Infiltration law and fire prevention and extinguishing effect of composite long-acting flame retardant liquid in coal body

ZHANG Likui; SHI Xin; LI Wenlin; LIU Longfei

doi:10.11799/ce202509014

Abstract：In order to clarify the infiltration law of blocking liquid inside coal under different injection conditions and improve the application effect of in-situ blocking technology,we took the B2 coal seam of Kuangou Coal Mine as the research object,and determined the optimal composite long-acting blocking liquid ratio with the best wetting performance through reverse spontaneous inhibition experiments;Then,based on the optimized ratio of the blocking fluid and relying on the three-axis coal seepage system,the effects of different axial pressures,confining pressures,injection pressures,and blocking fluid temperatures on the wetting law of the blocking fluid in the coal were tested;Finally,a gas coal water body movement monitoring experiment based on acoustic emission array was conducted to clarify the variation law of the infiltration velocity of the blocking fluid in coal under different injection conditions,determine the relevant injection parameters of the blocking fluid,and apply the in-situ blocking process for fire prevention and extinguishing in the I010206 working face of Kuangou Coal Mine.It was found that,under the optimal ratio of the blocking liquid determined through reverse spontaneous inhibition experiments,the height of the reverse spontaneous inhibition experiment can reach 16 cm after one day,and the wetting effect is excellent;The triaxial coal permeability test experiment shows that increasing axial pressure,injection pressure,and injection temperature can increase permeability,while increasing confining pressure can lead to a decrease in permeability;The monitoring experiment of gas coal water transport based on acoustic emission array shows that the injection pressure and injection temperature are positively correlated with the infiltration rate;After in-situ blocking,the residual coal falls into the goaf and is monitored by a bundle tube monitoring system,resulting in a significant decrease in CO concentration and good blocking effect.This study has a positive effect on clarifying the flow range of blocking fluid under complex injection conditions and the development of in-situ blocking technology.