Goaf Nitrogen Injection Fire-fighting Technology of Shallow Buried Depth Coal Seam

Taking northwest mining area Sandaogou Mine as the background, this paper adopts theoretical analysis and numerical simulation to study a wide range of shallow buried depth goaf nitrogen injection technology, the results show that: without using nitrogen injection measures, the oxidation zone distribution is obviously larger than that adopting nitrogen injection measures; after increasing the flow of nitrogen injection, the “oxidation zone” range of each layer in goaf reduced obviously. When a large number of air leakage passage is in gob, increasing the amount of nitrogen injection can effectively instead of air leakage in goaf to inert the mined-out area. Compared with the high concentration nitrogen accumulation area in different layers of gob, the higher of the horizon is, the smaller of the high concentration nitrogen accumulation area is, the smaller of the inerting area is.