The overlying
oxygen isolation device comprises a storage
yard, a plurality of double-flow
nitrogen conveying hoses are arranged on the upper surface of the storage
yard, the interval between every two adjacent double-flow
nitrogen conveying hoses is 0.5-3 m, a plurality of through grooves are formed in the outer surfaces of the double-flow
nitrogen conveying hoses, the through grooves are distributed in the axis direction of the double-flow nitrogen conveying hoses, and the through grooves are communicated with the double-flow nitrogen conveying hoses. And a plurality of lifting arc supports are fixedly mounted on the upper surface of the storage
yard corresponding to the double-flow nitrogen conveying hose. By arranging a double-flow nitrogen conveying hose, a nitrogen purifying and
drying device and a nitrogen detection box, high-concentration nitrogen sequentially passes through a
mixed gas buffer box, a first connecting
pipe, a gas inlet
pipe and a stable ventilation
pipe and enters the combustible rock soil through the double-flow nitrogen conveying hose, and meanwhile, the nitrogen purifying and
drying device extracts gas in the combustible rock soil; nitrogen rapidly enters the flammable rock-soil, air in the flammable rock-soil is rapidly extruded out through the nitrogen, and therefore the flammable rock-soil and the air are isolated, and
spontaneous combustion of the flammable rock-soil is prevented.