We're trying to get our CO2 in the fermenter hall down to reasonable levels. I had considered a heat-recovery ventilation system, but simply getting rid of the CO2 at the source makes better sense.

We have a lot of blow-off from our ferms, so I need a trap of some kind to separate the CO2 from the foam. Does anyone have any examples of such a system so I don't have to re-invent the wheel?

I'm considering using a 35 gallon plastic drum for a trap, but having some guidance would be nice.