COOLER FOR RESIDUE OF THERMAL DECOMPOSITION

PROBLEM TO BE SOLVED: To enable the maintenance of inactive atmosphere steadily and securely by arranging an exhaust gas supplying line to the exhaust part of a combustion melting furnace and forming the inactive atmosphere with the exhaust gas in cooling thermally decomposed residue under the inactive atmosphere out of thermally decomposed gas and thermally decomposed residue generated by thermally decomposing waste. SOLUTION: A combustion melting furnace combusts combustible component isolated from thermally decomposed residue out of the thermally decomposed gas and the thermally decomposed residue generated by thermally decomposing waste and non-combustible component is discharged as molten slug 53f into a discharging part 71 shielded from the air. The lower edge opening part of the discharging part 71 is located under the surface of water tank 63, and the molten slag 53f is cooled and solidified in the atmosphere shielded from the air. An exhaust gas feeding line L7 for feeding the exhaust gas G2 generated by the melting furnace into a cooler 57 is arranged to the exhaust part 71 and the exhaust gas G2 cooled by an exhaust gas water cooler 72 arranged to the gas feeding line L7 is transferred to the cooler 57 as the inactive gas.