Re: [PSUBS-MAILIST] Idea for homebrew CO2 absorber

["Michael B. Holt" <mholt@richmond.edu>]

Paul B wrote:
> 
> Hello,
> 
> I am a new member, my name is Paul. I have recently signed up for the
> mailing list. I may one day build a submarine (if I still have the desire
> and the money falls right). Right now I am gathering information and ideas.
> 
> I was wondering if anyone thought of using lime milk ( Ca(OH)2 * H2O ) as
> base for homebrew CO2 absorber. You could use a regular clear plastic bottle
> (like they use for soda) and run something like an aquarium bubbler in it.
> The reaction should follow as this:
> 
> Ca(OH)2 + CO2 -> CaCO3 + H2O
> CaCO3 + H2O + CO2 -> Ca(HCO3)2
> 
> Calcium carbonate ( CaCO3, chalk) is unsoluble.
> Calcium hydrocarbonate ( Ca(HCO3)2 ) IS soluble. So when the reaction goes
> far enough, instead of milky substance you should see clear water — that
> will be a sign to change the absorber.
> 
> The backdraw is that you have to put all your air through the water based
> solution, which will put more moisture in the air.
> 
> Dead lime should be dirt cheap. And if my calculations are correct, 72 grams
> (about 3 and a half oz.) should get you rid of more than 40 liters of CO2 —
> that's 2 hours of one person breathing.
> 
> What do you guys think? Or is this nonsense?

>From what I can see in a book I have here, you have described
a device first proposed in 1863.  A Professor Horstford (of
Cambridge, Massachusetts) described the same gadget, but 
using a hand-cranked fan.

As far as I can tell, it was not built.  But the theory seems
sound.

Look at Mark Ragan's book "Union and Confederate Submarine
Warfare in the Civil War," pages 110-111; a diagram is on
page 170.




Mike