Exhaust gas processing device

An exhaust gas processing device for preheating externally-supplied processing target exhaust gas within a device main body in the presence of moisture with heat from at least either an electric heater or a heat exchanger, and subsequently thermally decomposing the preheated exhaust gas with an atmospheric pressure plasma, the exhaust gas processing device comprising:

• the device main body having a heating decomposition chamber therein;
• a non-transferred type plasma generator installed at a top surface portion of the device main body;
• a tubular reactor installed within the device main body such that an upper end opening thereof is directed toward a plasma emission port of the plasma generator, the reactor having therein a second space in which a high-temperature decomposable gas component of the processing target exhaust gas is thermally decomposed with an atmospheric pressure plasma from the plasma generator;
• a moisture supply unit provided at an inlet side of the device main body and configured to supply moisture to the heating decomposition chamber;
• and
• at least either the heat exchanger or the electric heater disposed in a first space which is between an inner peripheral surface of the device main body and an outer peripheral surface of the reactor and into which the processing target exhaust gas is supplied, the heat exchanger being configured to transfer heat in the second space to the first space, wherein
• the reactor has a cylindrical shape whose both end surfaces are open, and includes a center portion which is narrowed and is a small-diameter trunk portion at a center thereof, a high-temperature reaction portion above the small-diameter trunk portion at the center, and a high-temperature exhaust portion below the small-diameter trunk portion at the center, and
• the heat exchanger is provided at the high-temperature exhaust portion.