| 摘要 |
PURPOSE:To perform efficient control by providing plural hoppers in the bottom part of a treating tank, connecting the hoppers to the suction side of a pump, connecting the discharge side to a means for separating and removing sludge and a system for returning sludge removing liquid to the treating tank, and changing over the connection of the hoppers and the pump during the treatment. CONSTITUTION:For examples, 4 hoppers 3-6 are provided in the bottom parts of a dip coating type treating tank 1, and the hoppers are connected to the suction side of a pump 13 via pipes 7-11 with valves and a conduit 12. The discharge side of the pump 13 is connected via a conduit 14 to a concentrating tank 15, and further to a filter 17 and a conduit 18 for returning the filtrate to the tank 1. First, only the hopper 2 is communicated with the pump 13, and part of the sludge and treated liquid in the hopper 2 are discharged to the tank 15. Upon lapse of a prescribed time, the communication between the hopper 2 and the pump 13 is interrupted and the hopper 3 is communicated with the pump 13. The sludge is discharged sequentially from the hoppers 4, 5, 6. After the treated liquid in the tank 15 is removed of sludge 19 with the filter 17, the liquid is returned through the conduit 18 into the tank 1. |
