PURPOSE: To incinerate waste tires efficiently and utilize heat energy generated therefrom effectively by utilizing a deep fluidized bed furnace to substantially gasify the wasted tires perfectly and burning products produced by thermal cracking in a combustion furnace under specified conditions.

CONSTITUTION: Fragments of waste tires, obtained by crushing the tires in a proper crushing machine into fragments of below 15cm, for example, are stored in hopper 1 and transferred to a feeder 4 at a constant quantitative rate through a transporting device 2 and a gas seal mechanism 3, successively, are fed into a deep fluid layer thermal cracking furnace 5, having a fluid floor of which depth is more than two times of the maximum diameter of the furnace, by the feeder 4. The cracking furnace 5 receives air from an air feeding line 17 and steam from a steam super heater 15, and thereby, disolves the fragments in fluid sand, and thus, separates gas mixture and carbon floating on said mixture from incondensable gas and gasified tar. Thereafter, separated gaseous components are burnt in a combustion furnace 14.