[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Silicone tubing and CO2

First, I'd like to thank Karen for a few sane words, and Cynthia for
putting them through to us.

On Sun, 19 Nov 2000, Paul Sears wrote:
> 	The quoted permeability for CO2 is such that if the tube wall is
> 1 mm thick, and the pressure across it is 1 cm of mercury, then you will
> lose about 2.5 x 10^-6 millilitres per second through each square centimetre
> of tube wall.  The partial pressure difference across mine is about 76 cm
> of mercury, so I may be losing a few mL per hour.

So this brings up a different idea entirely.  Couldn't someone use a
dead-end length of gas-permeable tubing as a CO2 reactor?

I'm thinking of something like a coil of tubing inside a canister, with
water circulated through the canister.  CO2 in the tubing and under
pressure would diffuse through the wall of the tubing and into the water
at a rate controlled entirely by the inlet pressure.  No openings to plug.  
Nothing that has to be regularly scrubbed clean and no question about
bubbles escaping from the system.  You would probably want a pressure
relief valve on the system to guard against rupture in the event that the
pressure walks away.

What kind of tubing might be sufficiently permeable to work in that

On a spectacular day in the high desert,

Roger Miller

who obviously doesn't live in the same place as Wright Huntley.