What comes out of the scrubber?

[scuba-punk]

Not trying to be dense, but when my expired breath (just air to keep the concept simple, roughly 79% N2, 16% O2 and 5% CO2) goes through the CO2 scrubber - what comes out the other end? How much of the C in the CO2 ends up in the adsorbent, and what chemically happens? I'm guessing (again, from what I've been able to find on the 'net) that some of the O2 is returned to the breathing loop, some stays with the adsorbent, while some reacts with the adsorbent so create H2O...

Just trying to figure out how a passive addition rebreather works.

thanks!

-Frank =-)

[pipedope]

Here is a good page on scrubber action;
http://www.iart.de/2002/eng/info/rcap.html

If you don't have it, you want to get "Mastering Rebreathers" by Jeffrey Bozanic. This book has the explanations of function and equations needed to understand the different rebreathers out there.

[scuba-punk]

Maybe I'll put that book on my Christmas list. The website was helpful too. I guess if I can figure out what the adsorbent is made out of (I know, it's sodalime, but that doesn't help - well, I guess maybe it does), I can use my mad, remedial chemistry skills and figure it out. Anybody remember how much a mole of N2 weighs? :)

-Frank =-)

[ianr33]

Sodalime is Calcium Hydroxide.It will react with CO2 this removing it from the gas phase
Ca(OH)2 +CO2------> CaCO3 +H20

The Calcium Carbonate (CaCO3) formed is a solid,probably looks very similar to the original Sodalime. Oygen will pass through the sodalime and not be affected by it in any way.

A mole of N2 has a mass of 28g

(please dont say it has a weight of 28grams,that drives us ex teachers INSANE :D )

[Genesis]

that reaction also produces heat (its exothermic) :)

[scuba-punk]

ianr33, I know it should have been mass, not weight. I'm an enginerd, but I'm used to people giving me a dumb look when I tell them that they don't weigh anything in kg's. They have weight in Newtons and kg's are the equivalent to Slugs in the imperial system... Just trying to make it easier on everyone.

Thanks for the info though. It's all starting to make sense now.

-Frank =-)

[pipedope]

http://www.halcyon.net/rebreather/index.shtml

[scuba-punk]

That's the one that got me started on my quest for knowledge :)

I guess at this point I'm kind of a luddite when it comes to rebreathers - I'd love to try one, but don't really want one. I'm just trying to learn more about them. Maybe I'll take a basic rebreather class. For the diving I do, they are really not neccessary - but the gadget freak in me is interested to learn more.

Thanks again to everyone for their help!

-Frank =-)

[pipedope]

http://www.nobubblediving.com/

http://www.atlimp.com/dive.htm

http://www.jetsam.ca/mod.php?mod=weblink&op=view_category&cid=1&start_num=0

I hope that these all work.
Tons of cool stuff on rebreathers on the web.