In order to solve the problem of low foaming multiplier and high cost when using solid foam material to seal the underground coal mine, a test study on the foaming characteristics of solid foam was conducted, by changing the ratio of two raw materials and adding yellow sand to compare and analyze the foaming effect, the best ratio of two raw materials and the percentage of adding yellow sand were got when the foaming multiplier of solid foam was maximum, and also the cost when adding sand and not adding sand, to seal the volume space Vm3 was also compared. According to the test results and the field application effect when sealing 23103 tailrace in sloping ditch coal mine, the maximum foaming multiplier of solid foam can be reached when the percentage of sand content of solid foam reached 25% and the ratio of raw materials A and B was 1:1.2, and the maximum multiplier was 14.220, which can play the best anti-fire prevention effect at this time.
