Membrane-based compressed air breathing system

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.