Liquid recovery filter

Patent metadata

Field	Value
Publication number	US-11890559-B2
Application number	US-202017000362-A
Country	US
Kind code	B2
Filing date	Aug 23, 2020
Priority date	Apr 30, 2012
Publication date	Feb 6, 2024
Grant date	Feb 6, 2024

Abstract

A liquid recovery filter assembly for recovering filtered liquid trapped within a core or downstream side of a filter element. Multiple embodiments each include a recovery port and a recovery filter in fluid communication with the core or downstream side of the filter element. The recovery port is opened following filtration operations to permit and to facilitate filtered liquid to flow from a downstream or outlet port, thus allowing recovery of liquid remaining in the filter core or downstream side following filtering operations. The recovery filter permits the introduction of pressurized gas to force the filtered liquids from the filter assembly without compromising the sterility and/or non-contaminant condition of the liquid. Additional aspects include exchangeable filter cartridges or filter elements in single and multi-round configurations, embodiments with aspiration tubes and dip tubes and still others with hydrophilic/hydrophobic recovery filters that function as filters and as valves for the recovery port.

First claim

What I claim as new and desire to secure by Letters Patent is:

1. A method of purging process liquids from a recovery filter assembly comprising the steps of:
providing a filter housing or shell having a shell wall with an upper end cap and a lower end cap, wherein the upper end cap and the lower end cap are secured to the shell wall, and wherein the combination of the shell wall and the end caps define an internal volume;
providing at least one process filter secured in the shell and occupying a portion of the internal volume, wherein the at least one process filter defines a filter core, and wherein an inner surface of the shell and an upstream designated surface of the process filter defines an upstream volume;
providing an inlet port extending from the housing in fluid communication with the upstream volume;
providing an outlet port extending from the housing in fluid communication with the filter core;
providing a recovery port extending from the housing, wherein the recovery port is in fluid communication with the filter core;
providing a recovery filter in-line with the recovery port, wherein the recovery filter is in fluid communication with the filter core;
infusing a gas into the recovery port and through the recovery filter into the filter core; and,
purging processed fluids retained in the filter core after a fluid processing procedure, wherein the processed fluids are purged out of the outlet port.

2. The method of claim 1 comprising the further step of providing the at least one processing filter with a defined bubble point.

3. The method of claim 2 comprising the further step of infusing the gas into the recovery port at a pressure that does not exceed the bubble point of the at least one processing filter.

4. The method of claim 1 comprising the further step of providing a recovery port bleed valve subassembly secured to the recovery port and comprising:
a bleed valve port defining an outer port channel and an inner port channel;
a bleed valve port valve stem dimensioned to fit within the outer port channel and the inner port channel, wherein the bleed valve port valve stem defines a recovery port valve stem channel and a radially disposed, recovery port valve stem bore that intersects the recovery port valve stem channel and provides fluid communication between the recovery port valve stem channel and the outer port channel and the inner port channel; and,
an adjustable recovery port valve cap having an inner wall that defines a recovery port valve cap channel, wherein the inner wall is formed with a helically oriented slot dimensioned to receive a pin secured to, and projecting from, the bleed valve port, wherein rotation of the valve cap about the recovery port causes the pin to move along the slot to move valve stem into, and out of, the bleed valve port.

5. The method of claim 1 wherein the at least one process filter comprises a membrane valve having a hydrophobic layer positioned upstream of a hydrophilic layer.

6. The method of claim 1 wherein the at least one process filter comprises a membrane valve comprising:
a processing filter having a portal defined by a gap, bore, slit, or other portal configuration;
a hydrophobic filter material positioned over one side of the processing filter; and,
a hydrophilic filter material positioned over a second side of the processing filter, wherein the hydrophobic filter material and the hydrophilic filter material are bonded or secured to the processing filter.

7. The method of claim 1 wherein the at least one process filter comprises a pleated membrane valve filter comprising:
a pleat pack having hydrophilic portions with at least one hydrophobic portion positioned between the hydrophilic portions and joined together with seams, wherein the material used to construct the valve filter is selected from the group consisting of hydrophobic filter material, hydrophilic filter material, a combination hydrophobic/hydrophilic filter material, a hydrophobic filter material with a modified surface to have a hydrophilic property, a hydrophilic filter material with a modified surface to have a hydrophobic property and combinations thereof.

8. The method of claim 1 , wherein the recovery filter assembly defines a recovery filter assembly channel in fluid communication with a downstream side of the at least one process filter and the recovery port, and wherein the recovery filter assembly is positioned between the filter element and the recovery port.

9. The method of claim 8 wherein the recovery filter assembly comprises a recovery filter housing that defines a recovery filter chamber, wherein the recovery filter is secured in the filter chamber, and portions defining a recovery filter assembly channel in fluid communication with the filter chamber, the recovery filter, the recovery port and the downstream side of the filter element.

10. The method of claim 1 comprising the further step of providing an upstream vent port in fluid communication with the upstream volume.

11. The method of claim 10 comprising the further step of providing a second gas filter inline with the upstream vent port.

12. The method of claim 1 comprising the further step of providing an upstream drain port in fluid communication with the upstream volume.

13. The method of claim 1 wherein the outlet port is disposed through a lower end of the filter shell and the recovery port is disposed through an upper end of the filter shell.

14. The method of claim 1 wherein the outlet port is disposed through an upper end of the filter shell and the recovery port is disposed through the upper end of the filter shell.

15. The method of claim 1 wherein the inlet port is disposed axially through an upper end of the filter shell and the outlet port is disposed through a lower end of the filter shell and extends substantially coaxially with the at least one process filter.

16. The method of claim 1 wherein the inlet port is disposed substantially radially through an upper end of the filter shell and the outlet port is disposed substantially radially through a lower end of the filter shell.

17. The method of claim 1 wherein the inlet port is disposed substantially radially through an upper end of the filter shell and the outlet port is disposed substantially radially through the upper end of the filter shell substantially opposite the inlet port.

18. The method of claim 1 wherein the inlet port is disposed substantially radially through a lower end of the filter shell and the outlet port is disposed substantially radially through an upper end of the filter shell, wherein the outlet port is positioned generally diametrically opposite the inlet port.

19. The method of claim 1 further comprising the step of providing an outlet drain port disposed through a lower end of the filter shell, wherein the lower drain port is in fluid communication with the filter core.

20. The method of claim 19 wherein the outlet port is disposed through an upper end of the filter shell.

Assignees

• Saint Gobain Performance Plastics Corp

Inventors

• Lin Zhenwu
• Andrews Jacob
• Hertrick Hannah C

Classifications

• B01D35/16 Primary

  Cleaning-out devices {, e.g. for removing the cake from the filter casing or for evacuating the last remnants of liquid} · CPC title

• B01D19/0031

  by filtration · CPC title

• B01D29/21

  with corrugated, folded or wound sheets · CPC title

• B01D29/52

  in parallel connection · CPC title

• B01D29/58

  arranged concentrically or coaxially · CPC title