SEAWATER DESALINATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a seawater desalination system capable of suppressing concentration polarization in a reverse osmosis membrane module, and reducing power consumption while maintaining permeation performance by a reverse osmosis membrane during a low load operation. ! SOLUTION: A seawater desalination system 100 comprises: a high pressure pump 1 which pressurizes seawater taken into the system; a reverse osmosis membrane module 2 which introduces pressurized seawater by the high pressure pump 1 and separates the seawater into concentrated water being high-concentration salt water and permeated water; and a circulation pump 3 which pressurizes a part of the concentrated water discharged from the reverse osmosis membrane module 2 and supplies it to the reverse osmosis membrane module 2 via a circulation flow path 14. Concentration polarization is suppressed by supplying concentrated water corresponding to a reduced amount of a supply flow rate from the high pressure pump 1 to the reverse osm