| 摘要 |
PROBLEM TO BE SOLVED: To provide a water treating agent containing no heavy metal and phosphorus and suitable especially to an open and circulation type cooling water system, to provide a water treating agent suitable to the open and circulation type cooling water system and also usable appropriately as basic treatment/ transition time treatment and to provide a water treating method. SOLUTION: A water treating agent is composed of (A) water soluble aluminate and (B) a specified ethylenic unsatd. sulfonic acid based copolymer, and the water treating agent for the basic treatment/transition time treatment is composed of (A) the water soluble aluminate and (C) a specified hydroxyl group containing ethylenic unsatd. carboxylic acid based copolymer, and in the water treating method, the water treating agent is added to a water system having <=30 mg/l SiO2 concn. so that (A) component concn. (based on Al) and (C) component concn. may be >=10 mg/l respectively. |
