PURPOSE: To provide a rotatable incinerator having excellent recovery efficiency of exhaust heat and a method for operating the same.

CONSTITUTION: A rotatable incinerator comprises at least a pair of combustion air supply tube 5 and combustion gas exhaust tube 6 provided at a cylindrical incinerator body 1 in which heating medium is charged in such a manner that combustion air is turned in a body 11 to incinerate material to be incinerated, and a heat accumulator 7 provided at the tube 5 to preheat the and. A method for operating the incinerator comprises the steps of heating the accumulator 7 with the combustion gas exhausted from the body 1, reversing the pair of the supply tube and the exhaust tube 6 by operating a switching valve to introduce the air into the accumulator 7, preheating the air by thermal energy of the gas for accumulating heat, then switching the valve to introduce the air into the other accumulator to similarly preheat the air in a repeated manner.