Coal mine goaf spontaneous combustion three-zone symbolic gas monitoring and nitrogen injection flame retardant integrated system and control method

The invention discloses a coal mine goaf spontaneous combustion three-zone symbolic gas monitoring and nitrogen injection flame retardant integrated system and a control method, and belongs to the technical field of coal mine safety monitoring. The coal mine goaf spontaneous combustion three-zone symbolic gas monitoring and nitrogen injection flame retardant integrated system comprises a gas collection system, a portable gas chromatographic analyzer and a nitrogen injection flame retardant system; the gas collecting system comprises protective steel pipes arranged in the air inlet way and the air return way and at least two beam pipes arranged in the protective steel pipes, the protective steel pipes are connected with collecting floral pipes of a three-way structure or/and a right-angle structure, and the collecting floral pipes gradually enter the deep position of the goaf along with continuous advancing of the stope face; a fixed sucking pump is arranged at one end of the protective steel pipe; the portabl