Experimental study on prevention of spontaneous combustion of coal by ionic surfactant solution injection in coal seam

The inhibitor liquid used in the fire-extinguishing technology for preventing spontaneous coal combustion is difficult to inject due to the hydrophobicity of coal. To improve the injection effect and enhance the inhibitory properties, a surfactant (SDS) is added to the inhibitor to prepare the inhibitor solution. The flow law of inhibitor solution in coal and the prevention and control mechanism of coal spontaneous combustion were studied by various experimental methods, the extents of inhibitory effects on spontaneous coal combustion are found to differ due to the variations in properties of these liquids. Among them, the SDS and NH4H2PO4 corrosion inhibitor solution configured according to 1:1, the surface tension is significantly lower than that of pure raw coal by 62%, and the heating rate is lower than that of pure raw coal by 39%. The research results show that under the same conditions, the wetting and inhibiting effect of the corrosion inhibitor solution containing SDS on the coal is significantly improved, which provides a theoretical basis for the improvement of the inhibitor's fire-fighting technology.