To continuously and efficiently pulverize a large sized object to be crushed such as a waste tire.

A crushing treatment passage 21 made to a sealing structure is formed on a movement part of a conveying conveyor 11 and sealing gates 22, 23 of two stages are provided on an entrance side and an exit side in the crushing treatment passage to form an introduction chamber 211 and a discharge chamber 212. A crushing treatment chamber 213 is formed between the introduction chamber and the discharge chamber and an appropriate number of burner bodies 24 for feeding compressed air and a fuel to an upper part of the crushing treatment chamber to ignite/burn it and downwardly injecting it as a high temperature jet stream of acoustic velocity or more from a nozzle port are provided at appropriate positions. A nitrogen generation mechanism 26 is separately provided and it is constituted by a crushing treatment mechanism part 2 for feeding a nitrogen gas with the jet injection stream to the crushing treatment chamber and provided with a fine power suction port 25 at an upper part; a material feeding mechanism part 3 for feeding the object to be crushed to the introduction chamber in every predetermined time; and a separation mechanism part 4 provided with powder separation parts 41, 42 and a suction fan 43 connected to the fine powder suction port of the crushing treatment chamber.