Investigating Critical Parameters for the Application of Liquid Carbon Dioxide in Fire Prevention and Extinguishing in Goaf.

Coal is one of the primary energy sources in China, and the hazard of mine spontaneous combustion is severe. With the development of technology and environmental protection requirements, liquid carbon dioxide fire prevention technology has been widely applied in the prevention and control of spontaneous combustion in goaf. The technical key to the application of liquid carbon dioxide fire prevention and extinguishing technology is how to determine the injection parameters. This paper, combining the law of heat conservation and the laser flash method, tests the thermal diffusivity, specific heat capacity, and thermal conductivity of coal at different temperatures. It also establishes the relationship functions of specific heat capacity and thermal conductivity with changes in coal sample temperature. Furthermore, by combining the laws of mass and heat transfer, the required amount of liquid carbon dioxide injection for the oxidation heating of goaf is calculated. This provides key parameters for the injection of liquid carbon dioxide in mines and constructs a mathematical model, offering a theoretical basis for the technology of fire prevention and extinguishing with liquid carbon dioxide. [ABSTRACT FROM AUTHOR]