Removing CO2 from a brathing loop

[brandrl]

What I would like to do is be able to remove CO2 from a Helium Oxygen Nitrogen breathing mix without relying on a sodalime chemical scrubber. can anyone on this site help me. Expired gas would be approx 5% CO2 on every breath. approx 1 liter per minute

 

[DaveHasse]

Few if any commercial membranes will display a significant CO2/He selectivity, so I don't think a membrane will completely replace the soda lime.

There has been work with possible commercialization on membrane contactors, with a membrane between the base and the gas stream. The system I have some knowledge of uses amines not soda lime. It was being projected for large scale natural gas operations, so it may also be a dead end.

Dave Hasse

 

[brandrl]

Dave thanks for the reply.I have heard that they use membranes in submarines to scrub O2 then they vent the O2 out into the water, out of the loop. This is similar to what I want,exept I would like to introduce Helium into the mix,Do you think this is possible
Larry