R134a - scrubbing from atmosphere

[riggsby]

Hello all,

Can anyone tell me whether there is a recommended type of filter (e.g. activated carbon) which can be used to extract R134a from the atmosphere in the event of a leak into a confined space? (a small submarine... very confined).

Thanks for any advice, I'm getting more out of this forum than I'm contributing!

Merry Christmas,

James.


(I've calculated percentage by volume resulting from a complete discharge of the refrigerant, and it's sufficiently low that asphyxiation won't be an issue - less than 4%, so my reason for wishing to remove it from the atmosphere is the possibility - albeit slight - of problems resulting from toxicity).

[Mazdamike]

Hi James

When we had a leak on a sub with R22, it was cleared buy large volume flexible ducked fans. One blowing, one sucking at the dockside. It is difficult to remove as most refrigerants are heavier than air. Not much use if you only have one hatch.

[Brian_UK]

Hi James

I don't know of any commercial machines that will do the task that you want.

You best bet is to ensure that your cooling system does not get damaged in the first place, carry one of these.. http://www.thermalgas.com/north2.html .. and get to the surface pronto. ;)

[Reflexive]

Large amounts of chilled higher boiling point refrigerant would work, basically a non polar "scrubber". R11, R123, could be used like they were sometimes as solvents for laundry.

[WINJA]

Does 134a have an affinity to water , what if you filtered the air thru a large bong ? just guessing

[Pyr0Beast]

Nope. Tho it could dissolve in alcohol slightly.
R134a is quite inert and would not adhere to ordinary carbon/calcium filters.
However, 0.4 v/v concentration can be considered to be lethal.

Ammonia does dissolve in water very well, a couple hundred liters of gas in one liter of water.

[Pyr0Beast]

Just a slight side note;
Leak detectors that need to be calibrated before use, must be calibrated outside on fresh air, otherwise they will not work properly.

Starting them in a room already full of gas will give absolutely no warning about dangerous concentrations or the measured values will be low, when actual values will be very very high.

[riggsby]

Hi,

The vehicle is equipped with self contained self rescue breathing apparatus, so it looks like it's going to be a case of use these and get to the surface fast, as Brian suggests.

Thanks for the replies, some interesting suggestions in there. Unfortunately we're a bit pushed for space to implement anything radical, but maybe next time!

James.

[Brian_UK]

Depending on the space available and how the equipment is built in - it might be prudent to carry a portable leak detector so that a check can be performed before submerging.

Samples ....

http://www.tequipment.net/TIFRefrigerantLeakDetectors.asp

[Pyr0Beast]

Why not use something like those Ice packs to cool the air? It is a lot safer and will not strain batteries.

Or the other possibility. A bottle of gas like nitrogen or preferably, oxygen which will cool itself once the pressure is lowered so the liquid gas starts vaporising ?

[Brian_UK]

Why not use something like those Ice packs to cool the air? It is a lot safer and will not strain batteries.

Or the other possibility. A bottle of gas like nitrogen or preferably, oxygen which will cool itself once the pressure is lowered so the liquid gas starts vaporising ?I hope that you are proposing that the gas is vented outboard ? :D

[Pyr0Beast]

Let's not smash the creativity :D