Described is a thermal decomposition treatment system and method of using the thermal decomposition treatment system wherein flammable waste is inputted into a trash burner which is shielded from air or gas and the waste is thermally decomposed and carbonized. The thermal decomposition treatment chamber includes a plurality of heating tubes wherein the flammable waste is inputted into the chambers while hot air is passed through the heating tubes which indirectly heats the flammable waste in an anaerobic environment the resulting gases are purified, recovered and reused.