| 摘要 |
PROBLEM TO BE SOLVED: To obtain the optimum cleaning effect with the optimum cleaning flow rate. SOLUTION: The unfiltered water is introduced into a filter basin 11, filtered and discharged through a filtered water valve 12. Backwashing water is supplied through a backwashing water valve 13 to clean the filter basin 11. A turbidimeter 14 for measuring the turbidity in the filter basin 11 is provided with a water temp. measuring function in addition to its tubidity measuring function. The turbidity and water temp. measured by the turbidimeter 14 are inputted to a sequencer 15, the turbidity and water temp. are calculated therein, and the set flow rate and cleaning termination signal are emitted from the sequencer 15. The set flow rate is inputted to a flow controller 16, then the flow control signal is supplied to the backwashing water valve 13 from the controller 16, and the backwashing water valve 13 is controlled in accordance with the control signal. When the filter basin 11 has been cleaned, a cleaning termination signal is inputted to the backwashing water valve 13 from the sequencer 15, and the valve 13 is closed.
|
