Desalination apparatus

• US 4,632,754 A
• Filed: 10/11/1983
• Issued: 12/30/1986
• Est. Priority Date: 10/12/1982
• Status: Expired due to Fees

• Current Assignee: Plessey Overseas Limited Vicarage Lane Ilford Essex 1G1 4AQ
• Original Assignee: Plessey Overseas Limited (Marconi Holdings Company Limited)
• Inventors: Wood, Robert S.
• Primary Examiner(s): SPEAR JR, FRANK
• Application Number:
  US06/540,762
• Time in Patent Office: 1,176 Days
• Field of Search: 210/134, 210/136, 210/416.1, 210/433.2, 210/34.1, 210/409, 210/257.2
• US Class Current: 210/257.2
• CPC Class Codes: B01D 2313/18 Specific valves
• CPC Class Codes: B01D 2313/243 Pumps
• CPC Class Codes: B01D 2313/50 Specific extra tanks
• CPC Class Codes: B01D 2313/502 Concentrate storage tanks
• CPC Class Codes: B01D 2321/02 Forward flushing
• CPC Class Codes: B01D 2321/10 Use of feed
• CPC Class Codes: B01D 61/08 Apparatus therefor
• CPC Class Codes: B01D 65/02 Membrane cleaning or sterilisation ; Membrane regeneration
• CPC Class Codes: Y02A 20/131 Reverse-osmosis

Abstract

Reverse osmosis liquid filtration apparatus, which apparatus comprises an inlet conduit, a reverse osmosis chamber, a pump for pumping liquid to be filtered from the liquid inlet conduit to the reverse osmosis chamber, a reverse osmosis membrane positioned in the reverse osmosis chamber and dividing the reverse osmosis chamber into a first portion for containing concentrated unfiltered liquid and a second portion for containing filtered liquid that has passed through the reverse osmosis membrane, a first outlet conduit which extends from the second portion of the reverse osmosis chamber and which is for the filtered liquid, a reservoir, reservoir separator means, a second outlet conduit for concentrated unfiltered liquid, and valve means.

Claims

1. Reverse osmosis liquid filtration apparatus, which apparatus comprises an inlet conduit, a reverse osmosis chamber, a pump for pumping liquid to be filtered from the inlet conduit to the reverse osmosis chamber, a reverse osmosis membrane positioned in the reverse osmosis chamber and dividing the reverse osmosis chamber into a first portion in communication with said inlet conduit for containing concentrated unfiltered liquid and a second portion for containing filtered liquid that has passed through the reverse osmosis membrane, a first outlet conduit which extends from the second portion of the reverse osmosis chamber and which is for the filtered liquid, a reservoir, reservoir separator means movable within the reservoir for dividing the reservoir into a first reservoir portion and a second reservoir portion, a second outlet conduit extending from the first portion of the reverse osmosis chamber for concentrated unfiltered liquid, and valve means in the form of a unitary plate valve including a housing having a plurality of outlets and a plurality of inlets communicating with the first portion of the reverse osmosis chamber, with the first reservoir portion, with the second reservoir portion, and with the second outlet conduit, and a rotatable plate member within said housing to provide communication between selected ones of said inlets and selected ones of said outlets for controlling the flow of liquids to and from the first portion of the reverse osmosis chamber and to and from the reservoir, the reservoir separator means and the valve means acting in co-operation in use of the apparatus on a forward movement of the reservoir separator member to allow unfiltered liquid to enter the first reservoir portion on a first side of the reservoir separator means and to substantially simultaneously expel from the second reservoir portion and through the valve means concentrated unfiltered liquid on a second side of the reservoir separator means, and the reservoir separator means acting in use of the apparatus on a return movement of the reservoir separator means and to cause the unfiltered liquid in the first reservoir portion on the first side of the reservoir separator means to enter the first portion of the reverse osmosis chamber to flush the first portion of the reverse osmosis chamber to wash concentrated unfiltered liquid from the first portion of the reverse osmosis chamber through the valve means and into the second reservoir portion on the second side of the reservoir separator means, which concentrated unfiltered liquid is then expelled from the second reservoir portion through the valve means and from the apparatus via the second outlet conduit on the next repeated forward movement of the reservoir separator means.

2. Apparatus according to claim 1 in whicthe plate valve is operated by a pressure operated vane actuator, the vane actuator operating on pressure differences generated within the apparatus during use of the apparatus.

3. Apparatus according to claim 2 in which the pressure differences are caused by the reservoir emptying and filling.

4. Apparatus according to claim 1 in which the plate valve is operated by a cam and gear box arrangement.

5. Apparatus according to claim 1 in which the reservoir separator means is a diaphragm.

6. Apparatus according to claim 1 and including a second pump for drawing liquid from the first portion of the reverse osmosis chamber and for delivering the liquid to the second side of the reservoir separator means.