PURPOSE: To reduce the necessary amount of washing water, by a method wherein the rotation of a blade is further continued after the supply of a treating liquid is stopped and the supply of washing water is commenced after a stored amount in a centrifugal thin film evaporator is reduced as possible.
CONSTITUTION: When a centrifugal thin film evaporator 13 is stopped, a motor 18 is succeedingly driven at a same rotary speed as during pulverization of concentrated waste liquid still after the stop of a fixed delivery pump 14 for supplying a definite amount of the concentrated waste liquid to the evaporator 13. At this time, the temp. of a thermocouple 17 is continuously measured and, when the rising rate of the temp. reaches a definite value or less, it is discriminated that the stored material in the evaporator 13 is eliminated. At this time, a three-way valve 19 is changed over, a valve 20 is closed which a valve 21 is opened to supply washing water to the evaporator 13. As the result, the washing can be commenced after the stored material in the evaporator 13 is eliminated, thus the necessary amount of washing water can be reduced.
KOYAMA TAKAO
MATSUDA MASAMI
MIURA HIDEKAZU
TAKAMURA YOSHIYUKI
| JPS53122675A | 1978-10-26 |