DEVICE AND METHOD OF WATER TREATMENT BY MEANS OF REVERSE OSMOSIS OR NANOFILTRATION Russian patent published in 2020 - IPC B01D61/02 B01D61/06 B01D61/12 C02F1/44 

FIELD: technological processes.

SUBSTANCE: invention relates to devices and methods which use reverse osmosis or nanofiltration membranes in order to remove dissolved solid phase from supplied water. Method of treating feed water in a device comprising a reverse osmosis (RO) or nanofiltration unit and a concentrate reservoir, said method comprising: a. in first mode of operation: i. unit for reverse osmosis (RO) or nanofiltration forms permeate and concentrate; ii. directing concentrate to accumulation tank for concentrate and accumulating concentrate therein; iii. separating permeate into first and second permeate streams; v. mixing the feed water with the second permeate stream to form a mixture of the supplied water with the permeate; vi. after mixing the feed water with the second permeate stream, directing the concentrate from the concentrate storage container and mixing the feed water – permeate with the concentrate mixture to form a second mixture; vii. increasing pressure and pumping of second mixture through unit for reverse osmosis (RO) or nanofiltration and formation of first and second streams of permeate and concentrate and continuation of concentrate to accumulation reservoir for concentrate; viii. during the first mode of operation, neither the supplied water nor the first or second permeate streams are directed to the concentrate reservoir; b. in second mode of operation: i. draining part of concentrate from accumulation tank for concentrate; ii. when part of concentrate is drained from accumulation tank for concentrate, increased pressure and direction of mixture of supplied water and permeate through unit for reverse osmosis (RO) or nanofiltration and continued formation of concentrate; iii. when part of concentrate is drained from accumulation tank for concentrate, continuation of concentrate from unit for reverse osmosis (RO) or nanofiltration into accumulation reservoir for concentrate; iv. during the second mode of operation, neither the supplied water, nor the first or second permeate flows are directed to the accumulation tank for the concentrate; and c. method is a continuous method, which continues to direct concentrate from the unit for reverse osmosis (RO) or nanofiltration into a storage container for concentrate in both first and second modes.

EFFECT: high degree of purification of water.

23 cl, 4 dwg