Membrane-based compressed air breathing system

• US 7,972,415 B2
• Filed: 12/11/2008
• Issued: 07/05/2011
• Est. Priority Date: 12/11/2008
• Status: Active Grant

• Current Assignee: Industrial Technologies & Services Americas Incorporated
• Original Assignee: SPX Corporation
• Inventors: Honath, Mark F., Fox, Timothy J.
• Primary Examiner(s): Greene; Jason M
• Application Number:
  US12/332,709
• Publication Number:
  US 20100150773A1
• Time in Patent Office: 936 Days
• Field of Search: 96/4, 96/8, 96/10, 961/08, 961/09, 961/11, 964/13, 964/17, 95/45, 95/52, 951/43, 952/73, 422/4, 422/119, 422/122, 423/246, 423/247, 423/437.2, 128/200.24, 128/205.12, 128/205.27, 128/205.29, 553/851, 553/15, 554/82, 55D/IG.17
• US Class Current: 95/45
• CPC Class Codes: A62B 7/10 with filter elements
• CPC Class Codes: B01D 2257/80 Water
• CPC Class Codes: B01D 2311/04 Specific process operations in the feed stream; Feed pretreatment
• CPC Class Codes: B01D 2311/06 Specific process operations in the permeate stream
• CPC Class Codes: B01D 2311/13 Use of sweep gas
• CPC Class Codes: B01D 2311/2626 Absorption or adsorption
• CPC Class Codes: B01D 2311/2649 Filtration
• CPC Class Codes: B01D 2311/2696 Catalytic reactions
• CPC Class Codes: B01D 2313/44 Cartridge types
• CPC Class Codes: B01D 53/268 by diffusion

Abstract

A breathing air purification device and method having a carbon-monoxide free sweep stream. Water vapor is removed from a compressed air stream using a membrane dryer, comprising, a membrane having a permeate portion and a non-permeate portion, a membrane housing which encases the membrane, a membrane feed inlet conduit connected to the membrane and a non-permeate gas outlet conduit fluidly connected to the non-permeate portion of the membrane. The sweep stream used to cleanse the outer permeate portion of the membrane dryer is taken from a catalyst filter. The catalyst filter includes a cartridge containing a bed of catalyst, two end pieces maintaining the cartridge within a catalyst bed housing and having outlet holes, a catalyst inlet conduit connected to the bed of catalyst and a product gas outlet conduit connected to the outlet holes. A sweep inlet tube provides a gas connection from the catalyst filter component to the permeate portion of the membrane.

Claims

1. A breathing air purification device, comprising:

a membrane separation component, comprising;

a membrane having a permeate portion and a non-permeate portion;

a membrane housing which encases the membrane;

a membrane feed inlet conduit connected to the membrane; and

a non-permeate gas outlet conduit fluidly connected to the non-permeate portion of the membrane;

a catalyst filter component, comprising;

a cartridge containing a bed of catalyst;

two end pieces maintaining the cartridge within a catalyst bed housing and having outlet holes;

a catalyst inlet conduit connected to the bed of catalyst and fluidly connected to the non-permeate gas outlet; and

a product gas outlet conduit connected to the outlet holes; and

a sweep inlet tube providing a gas connection from the catalyst filter component to the permeate portion of the membrane.

2. The breathing air purification device, as claimed in claim 1, further comprising a sweep orifice for metering an amount of gas which enters the permeate portion of the membrane.

3. The breathing air purification device, as claimed in claim 1, further comprising at least one pre-filter located upstream of the membrane separation component.

4. The breathing air purification device, as claimed in claim 1, further comprising a sweep inlet conduit within the membrane housing.

5. The breathing air purification device, as claimed in claim 1, further comprising a transfer tube in a center portion of the membrane for transferring a portion of the non-permeate product gas from the non-permeate portion of the membrane to the non-permeate gas outlet conduit.

6. The breathing air purification device, as claimed in claim 1, further comprising an activated carbon filter located downstream of the catalyst filter.

7. The breathing air purification device, as claimed in claim 6, further comprising a particulate filter located downstream of the activated carbon filter.

8. The breathing air purification device, as claimed in claim 1, wherein the catalyst filter includes a moisture indicator device.

9. The breathing air purification device, as claimed in claim 1, wherein the catalyst filter includes a plugged port for a carbon monoxide monitoring device.

10. The breathing air purification device, as claimed in claim 1, further comprising a filter mounting bracket attached to the membrane separation component.

11. The breathing air purification device, as claimed in claim 1, further comprising a filter mounting bracket attached to the catalyst filter component.

12. The breathing air purification device, as claimed in claim 1, further comprising a sweep filter fluidly connected to the sweep inlet tube.

13. The breathing air purification device, as claimed in claim 12, wherein the sweep filter is a sintered bronze filter.

14. The breathing air purification device, as claimed in claim 1, wherein the membrane housing incorporates a “

T-style”

filter housing.

15. The breathing air purification device, as claimed in claim 1, further comprising a pipe-threaded catalyst fitting which interlaces with the catalytic bed housing creating a fitted seal.

16. The breathing air purification device, as claimed in claim 15, further comprising an adapter fitting to maintain a connection between the pipe threading of the catalyst fitting and the sweep inlet tube.

17. The breathing air purification device, as claimed in claim 1, wherein a sweep gas stream, substantially free of carbon monoxide, flows from the catalyst filter component to the membrane separation component.

18. A breathing air purification device having a carbon-monoxide free sweep stream, comprising:

membrane separation means, comprising;

a separation means for separating a permeate portion from a non-permeate portion;

encasement means for encasing said separation means;

feed inlet means for carrying a feed gas into the device; and

a non-permeate product gas outlet means for carrying non-permeate product gas out of the membrane separation means;

catalyst filter means, comprising;

cartridge means for encasing a bed of catalyst;

end pieces means for maintaining the cartridge within a catalyst bed housing and having outlet means for carrying a catalyst-treated outlet gas out of the catalyst filter means; and

catalyst inlet means for receiving non-permeate product gas from the membrane separation means and introducing the non-permeate product gas into the bed of catalyst; and

a sweep inlet means for providing a gas connection from the catalyst filter component to the permeate portion of the membrane.

19. The breathing air purification device, as claimed in claim 18, further comprising a sweep orifice means for metering an amount of gas which enters the permeate portion.

20. The breathing air purification device, as claimed in claim 19, further comprising a sweep filter means for removing particulates from the gas which enters the sweep inlet means.

21. The breathing air purification device, as claimed in claim 18, further comprising pipe-threaded catalyst fitting means for interlacing with the catalytic bed housing forming a fitted seal.

22. The breathing air purification device, as claimed in claim 21, further comprising adapter fitting means for maintaining a connection between the pipe threaded catalyst fitting means and the sweep inlet means.

23. A method of using a breathing air purification device, comprising:

removing water vapor from a compressed air stream using a membrane separation component, comprising;

carrying the compressed air stream into the device;

separating a permeate portion from a non-permeate portion of the compressed air stream; and

carrying a non-permeate gas out of the membrane separation component;

removing carbon monoxide from the non-permeate gas using a catalyst filter component, comprising;

maintaining a cartridge within a catalyst bed housing end pieces having outlet holes for carrying a catalyst-treated gas out of the catalyst filter component; and

introducing the non-permeate gas into a bed of catalyst housed within the cartridge; and

transferring the catalyst-treated gas from the catalyst filter component to the permeate portion of the membrane via a sweep inlet conduit.

24. The method of using a breathing air purification device of claim 23, further comprising, metering an amount of gas which enters the sweep inlet conduit.

25. The method of using a breathing air purification device of claim 23, wherein the catalyst-treated gas is substantially free of carbon monoxide.