Reverse osmosis treatment device and method for cleaning reverse osmosis treatment device

摘要

A reverse osmosis treatment device (10) is equipped with: a first pressure vessel (80) for treating water to be treated and creating a primary effluent and first permeated water; a second pressure vessel (82) for treating the primary effluent and creating a secondary effluent and second permeated water; a first cleaning liquid storage tank (110) for storing a first cleaning liquid for cleaning the first pressure vessel; and a second cleaning liquid storage tank (112) for storing a second cleaning liquid for cleaning the second pressure vessel. Therein the first and second pressure vessels each have one reverse osmosis membrane element (22) equipped with a reverse osmosis membrane and positioned therein the vessels or a plurality of reverse osmosis membrane elements (22) connected in series via a water collecting pipe through which permeated water flows. Furthermore the first cleaning liquid storage tank is connected to a first concentrated water discharge pipe (62) of the first pressure vessel and the second cleaning liquid storage tank is connected to a primary effluent introduction pipe (68) of the second pressure vessel.