Reverse osmosis water-on-water control valve

Patent metadata

Field	Value
Publication number	US-9873087-B2
Application number	US-201314038000-A
Country	US
Kind code	B2
Filing date	Sep 26, 2013
Priority date	Oct 11, 2012
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

Described are water-on-water valves for use in reverse osmosis filtration systems. The water-on-water valves are regulated by the pressure in a product line, which contains fluid from a product line of the filter module and/or the product side of a water-on-water storage tank. Exemplary valves are shuttle valves that are regulated by the pressure downstream of the product side of a reverse osmosis filter module. The valves may comprise a piston within a housing, and an end of the piston may have an enlarged diameter relative to the maximum diameter of the remainder of the piston.

First claim

What is claimed is:

1. A filtration system comprising:
a water-on-water storage tank comprising a squeeze side and a product side separated by a membrane;
a filter module in fluid communication with the water-on-water storage tank, a feed source, a product outlet, and a drain outlet;
a feed line connecting the feed source to a feed inlet of the filter module;
a product line connecting a filtrate outlet of the filter module to the product side of the storage tank and the product outlet; and
a drain line connecting a reject outlet of the filter module to the squeeze side of the storage tank and the drain outlet of the system; and
a shuttle valve comprising a piston body in a housing, the piston body having a first group of sections effective to block fluid flow and a second group of sections with reduced diameter to enable fluid flow, the piston having a first end connected to a spring and a second end having a piston face with an enlarged diameter relative to the first group of sections, the second end enclosed in a chamber, an inlet check valve located between a product line port and the chamber and an outlet check valve located between the product line port and the chamber, and a plurality of ports including a drain port connected to the drain outlet, a tank squeeze port connected to the squeeze side of the storage tank, a reject port connected to a reject outlet of the filter element, and the product line port connected to the product outlet and to the product side of the storage tank, and wherein pressure in the product line acting on the piston face determines the position of the piston body.

2. The filtration system of claim 1 , wherein the piston body has at least three positions depending on the product line pressure on the piston face that moves the piston body, wherein:
the first position enables flow from the feed source to the filter module and from the reject outlet of the filter module to the squeeze side of the storage tank when there is flow through the product outlet,
the second position enables flow from the feed source to the filter module and from the squeeze side of the storage tank to the drain outlet of the system when there is not flow through the product outlet and the product side is not full, and
the third position blocks flow from the feed source into the filtration system when the product side is full.

3. The filtration system of claim 1 , wherein the filter module comprises a reverse osmosis filter.

4. The filtration system of claim 3 , wherein the filter module comprises one or more pre-filters upstream of the reverse osmosis filter.

5. The filtration system of claim 3 , wherein the filter module comprises a post-filter downstream from the product side of the storage tank.

6. The filtration system of claim 2 , further comprising a flow control regulator that regulates flow from the reject outlet of the filter module to the drain outlet of the system when the valve is in the first state.

7. The filtration system of claim 2 , further comprising a check valve located between the product side of the storage tank and the product line port to maintain a hold pressure during the third position.

8. A reverse osmosis water-on-water shuttle valve comprising:
the shuttle valve comprising a piston body in a housing, the piston body having a first end connected to a spring and a second end having a piston face with an enlarged diameter relative to the piston body, the diameter of the piston face is greater than a maximum diameter of the remaining piston body, the second end enclosed in a chamber, an inlet check valve located between a product line port and the chamber and an outlet check valve located between the product line port and the chamber and an outlet check valve to the chamber;
the shuttle valve having a valve feed inlet port, a valve feed outlet port, a drain port, a reject port, and a tank squeeze port, and the product port the piston body has at least three positions, wherein:
in the first position, a first fluid path is defined by the valve feed inlet port that is in fluid communication with the valve feed outlet port, and a second fluid path is defined by the reject port that is in fluid communication with the tank squeeze port;
in the second position, a third fluid path is defined by the valve feed inlet port that is in fluid communication with the valve feed outlet port, and a fourth fluid path is defined by the tank squeeze port that is in fluid communication with the drain port; and
in the third position, the valve feed inlet port is not in fluid communication with the valve feed outlet port.

9. The shuttle valve of claim 8 , wherein the piston body comprises a plurality of sections, a first group of sections each independently having a first diameter effective to block flow from or to one or more of the following: the valve feed inlet port, the valve feed outlet port, the drain port, the reject port, and the tank squeeze port depending on the state of the shuttle valve, and a second group of sections each independently having a reduced diameter with respect to one or more of the first diameters, effective to permit flow from or to one or more of the following: the valve feed inlet port, the valve feed outlet port, the drain port, the reject port, and the tank squeeze port depending on the state of the shuttle valve.

10. The valve of claim 9 , wherein the first group of sections are arranged in an alternating arrangement with the second group of sections.

11. The valve of claim 9 , wherein the piston body further comprises a flow slot to allow fluid communication between the valve feed inlet port and the valve feed outlet port as the valve moves from the third position to the first position.

12. The valve of claim 8 , further comprising a vent through the housing to allow air to be vented as the piston body moves between states.

13. The valve of claim 8 , further comprising a plurality of sealing devices, which during the first position, are effective to separate the first fluid path from the second fluid path, and during the second position, are effective to separate the third fluid path from the fourth fluid path.

14. The valve of claim 1 , wherein the inlet check valve has a cracking pressure greater than a cracking pressure of the outlet check valve.

15. A filtration system comprising:
a water-on-water storage tank comprising a squeeze side and a product side separated by a membrane;
a filter module connected to a feed source by a feed line, to a product outlet by a product line, and to a drain outlet by a drain line; and
the valve of claim 8 .

16. The filtration system of claim 15 , wherein pressure of the product line determines the position of the piston body.

17. The filtration system of claim 15 , further comprising a check valve in the product line to maintain a hold pressure on the valve during the third position.

18. The filtration system of claim 1 wherein the inlet check valve has a cracking pressure greater than a cracking pressure of the outlet check valve.

19. The filtration system of claim 7 wherein the check valve has a cracking pressure in the range from 0 to 0.5 psi, the inlet check valve has a cracking pressure in the range of 20 to 60 psi, and the outlet check valve has a cracking pressure in the range for 0 to 5 psi.

Assignees

• 3M Innovative Properties Co

Inventors

• Bassett Laurence W
• Zheng Dian

Classifications

• Y10T137/2567

  Alternate or successive inflows · CPC title

• F16K11/07

  with cylindrical slides · CPC title

• B01D61/10

  Accessories; Auxiliary operations · CPC title

• C02F2209/03

  Pressure · CPC title

• B01D61/06

  Energy recovery · CPC title