Cooling water treatment chemical and cooling water treatment method

摘要

PROBLEM TO BE SOLVED: To provide a cooling water treatment agent and a cooling water treatment method that suppress the corrosion of metals such as copper or copper alloy, or iron or iron alloy, forming a cooling water circulation passage, as well as that exert an algae control effect.SOLUTION: A cooling water treatment agent contains (A) pyridine-2-thiol-1-oxide or a salt thereof by 1 to 6 wt.%, (B) 1,2- benzisothiazolin-3-one by 1 to 7 wt.%, (C) a triazole compound by 0.5 to 2 wt.%, and (D) at least one of diethylene glycol and N-methylpyrrolidone by 0.1 to 10 wt.%, as an active ingredient, and is an aqueous solution with pH of 9 to 11.SELECTED DRAWING: None