SODIUM SALT SCALE-PREVENTING AGENT, SODIUM SALT SCALE-PREVENTING METHOD, AQUEOUS SYSTEM VISCOSITY-REDUCING AGENT, AQUEOUS SYSTEM MANAGEMENT METHOD, AND AQUEOUS SYSTEM VISCOSITY-REDUCING METHOD

The purpose of the present invention is to provide a method for preventing the occurrence of scale in aqueous systems that contain a large amount of sodium ions. This sodium salt scale-preventing agent comprises a sulfone group-containing polymer that has at least an unsaturated sulfonic acid-based monomer as monomers. It is preferable that for the sulfone group-containing polymer, the weight average molecular weight is 700 g/mol to 70,000 g/mol. When the total of the mole numbers of all of the monomers constituting the sulfone group-containing polymer is 100 mole%, the mole number of unsaturated sulfonic acid-based monomer constituting the sulfone group-containing polymer is preferably at least 3 mole%. 提供：一种防止含有大量钠离子的水系中的水垢的发生的方法。本发明的钠盐垢防止剂包含至少以不饱和磺酸系单体为单体的含磺基聚合物。含磺基聚合物的重均分子量优选700g/mol以上且70000g/mol以下。将构成含磺基聚合物的全部单体的摩尔数的总和设为100摩尔％的情况下，构成含磺基聚合物的不饱和磺酸系单体的摩尔数优选3摩尔％以上。