To provide the method and device for water treatment in an open circulation cooling water system, effecting high-condensing operation while preventing corrosion and scale without employing any chemical or employing the necessary minimum chemical.
In the water treatment method of open circulation cooling water systems 1, 3 employing the cooling water through circulation 2, 4, the high condensing operation is effected without discharging water or reducing the discharging amount of water while one part of the circulating cooling water in the cooling water systems is treated through desalting treatment 8 and the circulating cooling water in the cooling water systems is circulated while regulating the same so as to have the value of pH of 7.5-9.5, total silica concentration of 200 mg-SiO2/L or less, and the product of the magnesium hardness (mg- CaCO3/L) by the total silica concentration (mg-SiO2/L) will become 4,000-40,000. The desalting treatment can be effected employing a strong acidic cation exchange resin or the same and strong alkaline and/or weak alkaline anion exchange resin while corrosion preventing agent or scale preventing agent can be added to the circulating cooling water.
YAIDE NORIHIRO
MAKITA NORIO
