Abstract: The invention concerns a reverse osmosis system (1) with at least one membrane unit (2) comprising an inlet (3), a permeate outlet (4) and a concentrate outlet (5), a high-pressure pump (8) that is connected to the inlet (3), a pressure exchanger (11) comprising at least one high-pressure concentrate connection (HPC), and a booster pump. It is endeavored to achieve the lowest possible energy consumption. For this purpose, the booster pump is made as a displacement pump (16) that is arranged between the concentrate outlet (5) and the high-pressure concentrate connection (HPC) of the pressure exchanger (11).

Abstract: The invention concerns a valve arrangement (7) comprising a flow path (11) connecting an inlet (9) and an outlet (10), a closing means (12) arranged in said flow path (11), a resetting means and a first pressure in a first pressure chamber (14) acting in a closing direction on said closing means (12), a pressure of said outlet (10) and a second pressure in a second pressure chamber (18) corresponding to a pressure of said inlet (9) when said closing means (12) is closed acting in opening direction on said closing means (12), said first pressure chamber (14) being connectable to the outlet (10) via an auxiliary valve (13). It is intended to keep small a pressure pulse when opening the valve arrangement (7). This is achieved in that the closing means (12) having a first opening state (A) and a second opening state (B), a flow resistance of said closing means (12) in said first opening state (A) being larger than a flow resistance of said closing means in said second opening state (B).

Abstract: The invention concerns a reverse osmosis system (1) with at least one membrane unit (2) comprising an inlet (3), a permeate outlet (4) and a concentrate outlet (5), a high-pressure pump (8) that is connected to the inlet (3), a pressure exchanger (11) comprising at least one high-pressure concentrate connection (HPC), and a booster pump. It is endeavoured to achieve the lowest possible energy consumption. For this purpose, the booster pump is made as a displacement pump (16) that is arranged between the concentrate outlet (5) and the high-pressure concentrate connection (HPC) of the pressure exchanger (11).

Abstract: The invention concerns a valve arrangement (7) comprising a flow path (11) connecting an inlet (9) and an outlet (10), a closing means (12) arranged in said flow path (11), a resetting means and a first pressure in a first pressure chamber (14) acting in a closing direction on said closing means (12), a pressure of said outlet (10) and a second pressure in a second pressure chamber (18) corresponding to a pressure of said inlet (9) when said closing means (12) is closed acting in opening direction on said closing means (12), said first pressure chamber (14) being connectable to the outlet (10) via an auxiliary valve (13). It is intended to keep small a pressure pulse when opening the valve arrangement (7). This is achieved in that the closing means (12) having a first opening state (A) and a second opening state (B), a flow resistance of said closing means (12) in said first opening state (A) being larger than a flow resistance of said closing means in said second opening state (B).