| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for removing scum which can effectively remove scum even in a closed type treatment device. <P>SOLUTION: A controller 9 narrows the opening of a control valve 64 to increase the flow rate of treated water returned from a reaction tank 2 to an acid production tank 3, which raises the liquid level of the acid production tank 3. Thereby the scum accumulated near the liquid level is discharged together with the treated water from a scum discharge line 10 to the outside of a system through water sealing equipment 11. It is preferable that, before this discharge, the scum accumulated near the liquid level of the reaction tank 2 is transferred together with the treated water to the acid production tank 3 by a scum discharge line 7. <P>COPYRIGHT: (C)2004,JPO</p> |
