| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a basic treatment method to be carried out at start of operation of a cooling water system performing a phosphorus-free zinc treatment for preventing corrosion of a metal member in the system during operation. <P>SOLUTION: The basic treatment method of the cooling water system comprises, when starting the operation of the cooling water system performing the phosphorus-free zinc treatment, adjusting the pH of water inside the cooling water system to 8.4-8.6 and the calcium hardness to 400-500 mg/L in terms of CaCO<SB POS="POST">3</SB>, adding 5-50 mg/L of water-soluble polymer in solid content and 1-5 mg/L of zinc salt in terms of zinc, and circulating the water inside the water system for at least 1 day without applying any heat load. <P>COPYRIGHT: (C)2013,JPO&INPIT |
