To effectively decompose and remove dioxins in exhaust gas by blowing a catalyst having the dioxin decomposition power into the exhaust gas exhausted out of various kinds of ovens, bringing the catalyst into contact with the exhaust gas and decomposeing the dioxins in the exhaust gas.
In an exhaust gas treatment device of a steel manufacturing arc oven, a direct suction system 31 is connected with an oven top preheating device 21 for preheating metal scraps A by an exhaust gas generated from an arc oven 11. Also an indirect suction system 41 is connected with a hood covering the arc oven 11 and the oven top preheating device 21, and the suction systems 31 and 41 are jointed on their downstream sides and connected with a main bag filter 51 through a main suction fan 51a. Then, a catalyst B having the dioxin decomposition power is blown from a catalyst blowing means 81 into the exhaust gas from which dust is removed by the main bag filter 51, and the catalyst is brought into contact with the exhaust gas in an exhaust gas duct 71 to decompose the dioxins in the exhaust gas, and then the catalyst B is recovered by a sub-bag filter 61 and then returned to a hopper 81a in the constitution of the exhaust gas treatment device.
NIWA YUKIO
KITABAYASHI SHOJI
