WATER TREATMENT METHOD, AND WATER TREATMENT SYSTEM

摘要

Provided are a water treatment system and a water treatment method with which salt-containing water can be recycled with a high water recovery rate. In this water treatment system (400) and water treatment method, a scale inhibitor and a silica-scale inhibitor are supplied to water to be treated including Ca ions, SO4 ions, carbonate ions, and silica, and the water to be treated is subsequently separated by a second desalination unit (210) into treated water, and second concentrated water in which the Ca ions, SO4 ions, carbonate ions, and silica are concentrated. In a second crystallization unit (220), gypsum seed crystals are supplied to the second concentrated water, and gypsum crystallizes and is removed from the second concentrated water.