To remove the unburned object stuck to filter cloth of a bag filter.
This bag filter 10 is constituted so that the exhaust gas discharged from an incinerator 5 is introduced into the filter 10 through an inlet damper 31 and a catalyst for decomposing a harmful gas in the exhaust gas is deposited on the filter cloth 57. The filter 10 is operated by detecting (21) at least one of CO concentration and CO2 concentration of the exhaust gas passing on the downstream side of the cloth 57 when the incinerator 5 is started or stopped, bypassing (58) the exhaust gas by closing the damper 31 when the detected concentration exceeds the regulated value and introducing the exhaust gas controlled to be heated (11) to the prescribed temperature into the filter 10, so that the unburned component stuck to the cloth 57 is decomposed oxidatively and removed.
KATO YASUYOSHI
TAKAHASHI MASAHIRO
