SYSTEM FOR REVERSE OSMOSIS AND FOR PRESSURE RETARDED OSMOSIS

The present invention relates to a system for reverse osmosis, RO, and for pressure retarded osmosis, PRO, comprising: a RO subsystem (10) with a high-pressure RO chamber (11) and a low-pressure RO chamber (12) separated by a RO membrane (13), the high-pressure RO chamber (11) having a RO feed inlet (14) and a brine outlet (15) and the low-pressure RO chamber (12) having a permeate outlet (16); a PRO subsystem (20) with a high-pressure PRO chamber (21) and a low-pressure PRO chamber (22) separated by a PRO membrane (23), the high-pressure PRO chamber (21) having a draw inlet (24) and a draw outlet (25) and the low-pressure PRO chamber (22) having PRO feed inlet (26) and a PRO feed outlet (27); an induction motor (30) having a stator and a rotor, wherein the rotor is mechanically connected to an input shaft of a hydraulic pump (31) configured for providing a feed solution to the RO feed inlet (14) and to an output shaft of a hydraulic motor (32) configured for receiving a draw solution from the draw outlet (25). The invention further relates to a method for operating such system for RO/PRO and to the use of such system.