Carbon Dioxide Management

[bluc]

I lined my shed last year and this is now an issue for me. Plan too install some ventilation. I prob shouldnt be distilling in a fairly well sealed building anyway.
With two rum ferments going nuts I could "feel" the co2 in the room. Certainly would not want to sit down in there and get comfy...

[Chriss]

Compared to hydrogen and sulphur dioxides, Carbon dioxide is nothing.
That's twice I've had my breath taken away.

The air quality meter alarmed this morning. Yeah 3rd day of a corn wash. mmmm CO2

To reduce the vapours when distilling, I've placed a cotton cloth over the collection pot, so we don't get drunk from ethanol and whatever other gases are emitted any more.

But should us distillers be collecting CO2... dry ice is tasty.

Have we done anything as a race since this was put online:
https://www.abc.net.au/news/science/201 ... d=newsmail

[The Stig]

If you’re getting vapor from your collection vessel , your condenser isn’t working correctly.

[bluc]

If you have enough co2 in the room it most definately can be fatal. Someone unaware could sit down into a higher concentration and lose consciousness or worse :handgestures-thumbdown:

[howard]

CO nearly got me in the 1970s
i did an explosive gas test before entering an underground structure but i didn't get my davey lamp out. :angry-banghead:
probably up to my waist in CO, moving about stirred it up, finished the 1/2 hour job and just managed to crawl out.
i didn't realise what was going on at the time, it's a quiet killer, but i was nauseous dizzy and wobbly for a few hours after.
very lucky.
not as lucky as two of our techs and a milkman.
first tech went into the u/g structure and collapsed pretty quickly.
the topman called over a passing milkman to help, they both went down to help the first tech but both collapsed quickly as well.
all 3 died very quickly without a struggle.

as for co being heavier than air, before we got mechanical air blowers, we had to lower empty buckets into the CO.
wait until the bucket was 'full', then pull it out and 'empty' the CO downhill/over the crown of the road.
the sight of blokes carefully carrying 'empty' buckets and emptying them amused many people.
some thought they they were on Candid Camera. :smile:

[brewbruz]

OK I'll try this again in the hope that we can actually have a sensible discussion about this given that CO2 is dangerous.

Too much of anything is dangerous. The key is understanding the hazardous quantity involved relative to the physiological or toxic effect as a function of concentration/dose.

According to this piece of reasoning:
https://lifefermented.wordpress.com/2014/01/22/how-much-co2-is-produced-from-brewing/
a 20'ish L brew generates around 450 L of CO2. Quantities will vary depending on the amount of sugar that the yeast has available to munch on and other relevant factors.

Evolution of CO2 occurs over time:
https://homebrewjournals.com/how-long-do-you-brew-beer/
So, a 1 - 2 week timeframe (depending), noting that CO2 generation will be more vigorous in the early stages of the process. The point being that the generated CO2 doesn't discharge to atmosphere at the snap of your fingers. However, if the fermentation is taking place in a small, gas tight space (fermentation fridge?) or a room with little ventilation, then CO2 levels will be a concern.

From the info available above, it's possible to derive a rough estimate of the daily CO2 production and factor that in to dimensions of the space used for fermentation and how open it is to the outside world. How often does the room get traffic where doors are open/closed that mixes up the air in the room? What kind of forced ventilation is typically operating, e.g. a fan? What about natural ventilation? Or an open window? From that, an understanding of how risky the work space is can be gauged.

Note that one comment above mentions that CO2 is denser than air, so it will tend to slump and will not be buoyant. So, I'd agree that brewing / fermenting in a basement is not ideal. The upside is that you can walk into a slumped cloud of CO2 and, so long as the cloud volume isn't excessive, your mouth can breath clean air. You'll have a problem if you decide to lie down for some reason though. And if you've got a dachshund, then keep them out of your workspace for their own health.

Physiologically, CO2 triggers the body's breathing response:
https://en.wikipedia.org/wiki/Carbon_dioxide#Human_physiology
So, a clue that you're in an environment with excessive CO2 levels is that your breathing rate will increase above normal.

Please don't confuse CO for CO2, the former is seriously toxic:
https://en.wikipedia.org/wiki/Carbon_monoxide#Toxicity
and can lead to the kind of nasty experience that howard relates.

All that leads me to expect that for DIY production quantities, CO2 is probably not a significant concern for the majority. Even so, there are always exceptions and understanding the relevant physics is a good way to avoid being caught out.

Thanks to Prof Green. This thread has been a handy thought exercise.

[brewbruz]

For completeness/convenience, and as a follow on, details on CO2's physiological effects are available at the links below:
https://en.wikipedia.org/wiki/Carbon_dioxide#Toxicity
https://en.wikipedia.org/wiki/Hypercapnia

Remember Apollo 13 - "Uh, Houston, we've had a problem" - that resulted in the astronauts needing to rig up improvised CO2 absorbers to keep the cabin environment safe?

[JammL]

For completeness/convenience, and as a follow on, details on CO2's physiological effects are available at the links below:
https://en.wikipedia.org/wiki/Carbon_dioxide#Toxicity/
https://en.wikipedia.org/wiki/Hypercapnia

Remember Apollo 13 - "Uh, Houston, we've had a problem" - that resulted in the astronauts needing to rig up improvised CO2 absorbers to keep the cabin environment safe?

I wish I hadn't read those articles. Now I'll be thinking about the harm of beer.

[harold01]

CO nearly got me in the 1970s
i did an explosive gas test before entering an underground structure but i didn't get my davey lamp out. :angry-banghead:
probably up to my waist in CO, moving about stirred it up, finished the 1/2 hour job and just managed to crawl out.
i didn't realise what was going on at the time, it's a quiet killer, but i was nauseous dizzy and wobbly for a few hours after.
very lucky.
not as lucky as two of our techs and a milkman.
first tech went into the u/g structure and collapsed pretty quickly.
the topman called over a passing milkman to help, they both went down to help the first tech but both collapsed quickly as well.
all 3 died very quickly without a struggle.

as for co being heavier than air, before we got mechanical air blowers, we had to lower empty buckets into the CO.
wait until the bucket was 'full', then pull it out and 'empty' the CO downhill/over the crown of the road.
the sight of blokes carefully carrying 'empty' buckets and emptying them amused many people.
some thought they they were on Candid Camera. :smile:

Howard
I am building a dedicated room for distilling which will be fully lined, after reading your post I will be adding exhaust fans at a very low level in the walls.
Thanks for the heads up