Method for processing cooling water system

摘要

A method for treating a cooling water system comprises adding, in a cooling water system having calcium hardness of 250 mg/L or less as CaCO3, a treatment agent containing a (meth)acrylic acid-based copolymer. The (meth)acrylic acid-based copolymer comprises a structural unit (a) derived from a (meth)acrylic acid-based monomer (A) represented by the following general formula (1) and a structural unit (b) derived from a specific (meth)allyl ether-based monomer (B) represented by the following general formula (2), a content of the structural unit (b) is 1 to 15 mol % relative to 100 mol % of structural units derived from all the monomers, a weight average molecular weight of the (meth)acrylic acid-based copolymer is 7,000 to 28,000, and at least one of the main chain terminals of the (meth)acrylic acid-based copolymer is a sulfonic acid group or a salt thereof.

主权项

1. A method for treating a cooling water system, comprising:
adding, in a cooling water system of calcium hardness of 250 mg/L or less as CaCO3, a treatment agent containing a (meth)acrylic acid-based copolymer, wherein the (meth)acrylic acid-based copolymer comprises a first structural unit derived from a (meth)acrylic acid-based monomer represented by formula (1) and a second structural unit derived from a (meth)allyl ether-based monomer represented by formula (2), a content of the second structural unit is 1 to 15 mol % relative to 100 mol % of structural units derived from all the monomers, a weight average molecular weight of the (meth)acrylic acid-based copolymer is 7,000 to 28,000, and at least one of main chain terminals of the (meth)acrylic acid-based copolymer is a sulfonic acid group or a salt thereof: where R1 represents a hydrogen atom or a methyl group; and X represents a hydrogen atom, a metal atom, an ammonium group, or an organic amine group; and where R2 represents a hydrogen atom or a methyl group; Y and Z each independently represent a hydroxyl group, or a sulfonic acid group or a salt thereof; and at least one of Y and Z represents a sulfonic acid group or a salt thereof.