REMOVAL METHOD FOR DEPOSITS ADHERING TO REACTOR COOLING WATER FLOW PASSAGE

PURPOSE: To remove deposits adhering to the surface of a reactor cooling water flow passage without using any chemical by applying the constitution that reduced water treated to negative oxidation reduced potential via the high-frequency electrolytic treatment method is supplied to the surface over the preset period. CONSTITUTION: The double cooling system of a steam generator(SG) 1 is filled with reduced water 7 treated to oxidation-reduction potential and obtainable from the high-frequency electrolytic treatment method involving an electrolysis process under the application of high-frequency voltage having both positive and negative amplitude values and/or an asymmetric duty ratio, by use of a main reducer 6. Thereafter, the reduced water 7 is sucked on the operation of a pump 10 through a pipeline 9 communicated from the inspection hole 8 of the SG 1 to the reducer 6, and circulated through a circulation passage laid for the return thereof to the SG 1 through a pipeline 12 communicated from the reducer 6 to a secondary cooling water manhole 11 above the SG 1. Furthermore, filters 14 and 15 provided in the pipelines 9 and 12 are used to arrest deposits grained and released.