Title of Invention

METHOD AND DEVICE FOR DESAALTING WATER BY REVERSE OSMOSIS

Abstract

The invention pertains to a method and a device for desalting water by reverse osmosis, particularly for desalting seawater, in which saltwater (10) is introduced under a first pressure (pi) into a pressure-compensation device (2) and conducted from pressure-compensation device (2) at a second, higher pressure (pa) into a membrane module (3), wherein desalted water (12) and concentrated saltwater (13) are conducted out of membrane module (3), wherein the concentrated saltwater (13) conducted out of membrane module (3) is continuously introduced at roughly second pressure (pa) into pressure-compensation device (2) and used there to apply roughly second pressure (pi) to saltwater (10) introduced into pressure-compensation device (2) and to introduce saltwater (11) into membrane module (3), and wherein the introduction of concentrated saltwater (13) into pressure-compensation device (2) and the conduction of concentrated saltwater (14) out of pressure-compensation device (2) are accomplished by means of controlled main valves (V1,V3,V4,V6). The main valves are subject to high mechanical stresses, particularly during the opening and closing of the valves. To reduce or avoid these, it is provided according to the invention that secondary valves (V2, V2’,V5,V5’) arranged in parallel with main valves (V1,V3,V4,V6) are controlled such that load peaks during opening and/or closing of main valves (V1,V3,V4,V6) are reduced. (Figure 2)

Full Text

The invention pertains to a method for desalting water by reverse osmosis according to the precarious; of Claim 1, as well as to a device for carrying out this method. Such a method and such a device are described in German Patent Application Cn. 199 33 1.47.2. Therein, the saltwater is introduced under a tryst pressure into a pressure-compensation device and introduced from the pressure-compensation device, under a second, higher pressure, into a membrane module, desalted water and concentrated saltwater being removed from the membrane module. Desalted water is to be understood here as water with a salt content reduced in relation to the saltwater introduced into the device. To increase the efficiency aide thus the energy balance for such a method and such a device, it is proposed there that the concentrated saltwater removed from the membrane module be introduced continuously under the second pressure into the pressure-compensation device, and be used there to apply the second pressure to the saltwater introduced into the pressure-compensation device and to introduce the saltwater into the membrane module. Introduction of the concentrated saltwater into tuff’s pressure-compensation device is accomplished wife check valves, and draining of the concentrated saltwater out of the pressure compensation device is accomplished here by means of controlled main valves. These controlled main valves are preferably actively controllable, and arc an-ganged in the appropriate connecting lines between the membrane module and the pressure compensation device or between the pressure-compensation device and the output for the concentrated saltwater. 1. Medicos for desalting water by reverse osmosis, particularly for desalting seawater, in which saltwater (10) is introduced under a first pressure (pi) into a pressure-compensation device (2) and conducted from pressure-compensation device (2) at a second^ higher pressure (p2) into a membrane nodule (3), wherein desalted water (12) and concentrated saltwater (13) are conducted out of membrane module (3)» wherein the concentrated saltwater (13) conducted out of membrane module (3) is continuously introduced at roughly second pressure (p:) into pre5isu::e-compensation device (2) and use there to apply regularly second pressure (p2) to saltwater (10) introduced into pressure-compensation device (2) and to introduce saltwater (11) into moraine module (3), and wherein the introduction of concentrated saltwater (13) into -compensation device (2) and the conduction of concentrated saltwater (14) out of compensation device (2) aide accomplished by means of controlled main valves (VLV:3,V4,V6). wherein secondary valves (V2,V2',V5.V5') arranged in parallel with main valves (V1,V3,V4,V6) are controlled such that load peaks during opening and/or closing of main valves (V1,V3,V4,V6) are reduced, for which purpose secondary valves (V2,V2',V5,V5') are opened at Cat during the opening or closing of the respective main valve (V1,V3,V4,V6) axing panicle thereto, characterized in that pressure fluctuations are compensated by means of a pressure reservoir (P) arranged at the input of pressure-compensation device (2) via which concentrated saltwater (13) is introduced from membrane module (3). 2. Method according to Claim 1, characterized in that concentrated saltwater (13) from membrane module (3) is introduced into an outlet chamber (101,102) of one of at least two pistoa-'cylindtir devices (401,402) of pressure-compensation device (2) at roughly second pressure (pj) and acts there on piston (301,302) such that saltwater (10) introduced into an inlet chamber (201,202) of the same piston/cylinder device (401,402) is conducted at roughly second prefigured (p ) into membrane module (3). 3. Method according to Claim 2, characterized in that concentrated saltwater (13) is alternately introduced into outlet chamber (101,102) of one of piston/cylinder devices (401,402), where by sultanate (11) is simultaneously conducted out of the respective inlet chamber (201,2.02) of the same piston/cylinder device (401,402) to membrane module (3), and in that saltwater (10) is simultaneously introduced into inlet chamber (201,202) of another person/cylinder device (401.402) at first pressure (pO, whereby concentrated saltwater (14) is conducted out of outlet chamber (101,102) of the same piston/cylinder device (401,402) at low pressure. 4. Cathode according to Claim 3, characterized in that piston/cylinder devices (401,402) of pressure-compensation device (2) are controlled such that, simultaneously, saltwater (10) is introduced into inlet chamber (201,202) of at least one piston/cylinder device (401,402), concentrated saltwater (14) is conducted out of outlet chamber (101,102) of the same piston/cylinder device (401,402), concentrated saltwater (13) is introduced into outlet chamber (101,102) of at least one other piston/sunder device (401,402), and saltwater (11) is fed to membrane module (3) from inlet chamber (201.202) of the same piston/cylinder device (401,402). 5. Method according to one of the preceding claims, characterized in that pressure-compensation device (2) comprises two piston/cylinder devices (401,402) operating in opposite phase and in that pistons (301,302) of piston/cylinder device (401,402) are connected by connecting rod (30). 6. Method according to Claim 5, characterized in that connecting rod (30) is driven by mean 3 of a craved unit. 7. Method according to one of the preceding claims, characterized in that the cross ■sector-n of secondary valves (V2,V2*,V5,V50 is smaller than the cross section of main valves (V1,V3,V4,V6). 8. Method according to one of the preceding claims, characterized in that the maximum flow -amounts through secondary valves (V2,V2',V5,V5') arc controlled by means of flow limiters (Rl ,R2,R3) in the feed lines to the secondary valves. 9. Method according to one of the preceding claims, characterized in that secondary valves (V2,V2',V5,V5') are opened only during the opening or closing process of tiie respective main valve (yi,V3,V4,V6) arranged in parallel thereto. 10. Method according to one of the preceding claims, characterized in that control of the main and secondary valves is done such that the main valves switch unpressurized. 11. Method according to one of the preceding claims, characterized in that the position of pistons (301,302) is continuously determined. 12. Method according to one of the preceding claims, characterized in that pressure-compensation device (2) comprises several pairs of piston/cylinder devices (401,402), each connected by a connecting rod (30), and in that the pairs arc operated offset in phase. 13. Device for carrying out the method according to one of the preceding claims, with a supply pump (1) for introducing saltwater (10) into pressure-compensation device (2) and with a membrane module (3) for separating salvager (11) introduced from pressure-compensation device (2) into desalted water (12) and concentrated saltwater (13), wherein a connecting line (4) [sic; (5)] continuously under pressure (p2) during operation is provided between membrane module (3) mind pressure-compensation device (2) for. respectively, feeding concentrated saltwater (13) from membrane module (3) to pressure-compensation device (2) and for feeding saltwater (11) from pressure-compensation device (2) to membrane module (3), and wherein controlled main valves (V1,V3,V4,V6) are provided for introducing concentrated saltwater (13) into presume-compensation device (2) and for conducting concentrated saltwater (14) out of pressure-condensation device (2), wherein secondary valves (V2,V2\V5,V5') in parallel with main valves (V1,V3,V4,V6) are arranged for reducing load peaks during opening and/or closing of main valves CV1,V3,V4,V6), for which purpose secondary valves (V2,V2'.V5,V5') are opened at the opening or closing of the respective main valve (Vl,V3,V4,V6) arranged parallel thereto, characterized in that pressure fluctuations are compensated by means of a pressure reservoir (P) arranged at the input of pressure-compensation device (2) via which concentrated saltwater (13) is introduced from membrane module (3). [amended page 2:] second pressure... and to introduce the saltwater into the membrane module. Introduction of the concentrated saltwater out of the pressure-compensation device is accomplished with check does, and draining of the concentrated saltwater out of the pressure compensation device is accomplished here by means of controlled main valves. These controlled main valves arc preferably actively controllable, and are outranged in the appropriate connecting lines between the membrane module and the pressure-compensation device or between the pressure-compensation device and the output for the concentrated saltwater. 14, A method for desalting water substantially as herein described with reference to the accompanying drawings.

Documents:

766-chenp-2003-abstract.pdf

766-chenp-2003-claims filed.pdf

766-chenp-2003-claims granted.pdf

766-chenp-2003-correspondnece-others.pdf

766-chenp-2003-correspondnece-po.pdf

766-chenp-2003-description(complete) filed.pdf

766-chenp-2003-description(complete) granted.pdf

766-chenp-2003-drawings.pdf

766-chenp-2003-form 1.pdf

766-chenp-2003-form 19.pdf

766-chenp-2003-form 26.pdf

766-chenp-2003-form 3.pdf

766-chenp-2003-form 5.pdf

766-chenp-2003-pct.pdf

abs-766-chenp-2003.jpg