METHOD FOR PREVENTING DEPOSITION OF SILICA SCALE

PROBLEM TO BE SOLVED: To provide a method for preventing deposition of a silica scale of an open type circulating cold water system using refilling water having a high silica concentration in the open type circulating cold water system. SOLUTION: In the method for preventing a deposition of the silica scale of the open type circulating cold water system, a discharge water amount or a refilling water amount of the open type circulating cold water system is controlled so that a calculated silica concentration (SC) = (N) × (S) defined as the product of a concentrated degree (N) of the open type circulating cold water system and the silica concentration (S) of the refilling water to the open type circulating cold water system is not more than a specific value which is set from a range of 180 to 230 mg/L. Preferably, the concentrated degree (N) is measured as a ratio (ECR/ECM)of the electric conductivity (ECR) of circulating water and the electric conductivity (ECM) of the refilling water to control the calculated silica concentration (SC). COPYRIGHT: (C)2005,JPO&NCIPI