Abstract：In order to avoid coal spontaneous combustion occurred in the goaf, it is necessary to infuse nitrogen into the goaf when the tridimensional drainage manner, which includes an exalted and rear laneway, is used to the high-methane and spontaneous combustion coal seam goaf.As an example of 15201 working-face in Shaqu coalmine of Huajin coking coal Co.Ltd., based on the confirmation of compartmentalization criterion of goaf spontaneous combustion three-zone and by means of a pipe-burying test method, the goaf nitrogen and oxygen distribution characteristic before and after nitrogen-infusing and nitrogen movement law have been investigated.It is indicated that the nitrogen mixes with goaf original gases after nitrogen-infusing, and the mixed gas moves together with the actions of air leak pressure and nitrogen-infusing pressure in the goaf.As oxygen concentration descend in the area influenced by nitrogen, the oxidation zone scope and the fatalness of coal spontaneous combustion in goaf have been reduced.It can provide reference bases for the optimization of nitrogen-infusing parameters and enhancing the effect of nitrogen-infusing fireproofing in other working-faces.

Keyword：fully mechanized caving mining working-face;goaf;spontaneous combustion three-zone;nitrogen-infusing;sign gas;