The fire inhibition characteristics of composite inert gas and its application potential analysis

Abstract

As the conventional inert gas used for coal firefighting, mainly CO2 and N2, experience certain deficiencies when used in coal firefighting under particular geological conditions, composite inert gas can be a feasible choice in such situations. Nevertheless, the fire inhibition characteristics and application potential of composite inert gas have not been explored in depth. To expedite the wider use of composite inert gas in preventing and controlling coal spontaneous combustion, the fire inhibition characteristics and application potential of composite inert gas have been evaluated by using temperature programmed experiment and engineering analogy for the first time. The results show that the fire inhibition effect falls in the order of as N2 < composite inert gas < CO2, and as the result of the competitive adsorption, the composite inert gas exhibits better performance than N2 and more resembles CO2 in the fire inhibition; Moreover, since the composite inert gas has lower toxicity and cost than CO2, the cost of composite inert gas is only 57.1% of CO2, it offers an overall more balanced performance taking into account fire protection effect, safety, and fire protection cost. The unique advantages of composite inert gas allow broad application in the prevention and control of the coal spontaneous combustion under some special geological environments.