Connecting fermentor to kegs

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MugsWorth

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This is my maiden voyage at co2 transfer and spunding. I think I'm doing this right. Got a line connected from fermenter to a dry hop keg with a floating diptube filled with sanitizer pushing it to another keg with a sounding valve set low. Does this sound correct? Except it's taking forever for the sanitizer to get to the last keg. Hmm. Maybe I have a leak somewhere.
 

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doug293cz

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This is my maiden voyage at co2 transfer and spunding. I think I'm doing this right. Got a line connected from fermenter to a dry hop keg with a floating diptube filled with sanitizer pushing it to another keg with a sounding valve set low. Does this sound correct? Except it's taking forever for the sanitizer to get to the last keg. Hmm. Maybe I have a leak somewhere.
During the most active fermentation, you should be producing about 100L of CO2 per day. A keg holds about 20L, so it should only take about 1/5 of a day, or ~5 hours to push the sanitizer from one keg to another. How long have you been watching/waiting?

Brew on :mug:
 

AlexKay

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Question for all the fermentation-gas purgers out there: do you worry about other fermentation gases (H2S, DMS) being captured and making it into the brew-to-be-kegged? CO2 recovery systems in pro breweries all seem to include a purification step before reuse.
 
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MugsWorth

MugsWorth

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Hi Doug
Its been about an hr. Oops, I had the spunding valve on. What pressure should I set it to?
Was considering connecting another keg from my blowtie, but since I don't know what I'm doing might reconsider, lol 😆
 

doug293cz

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Question for all the fermentation-gas purgers out there: do you worry about other fermentation gases (H2S, DMS) being captured and making it into the brew-to-be-kegged? CO2 recovery systems in pro breweries all seem to include a purification step before reuse.
For any volatile substances that come out of the beer during fermentation, they come out because the beer is already saturated with that substance, at the partial pressure of that substance in the headspace. If you are just purging kegs with the fermentation CO2, then almost all of that CO2 (and trace gases) are displaced from the keg when it is filled with beer. There won't be enough of the trace gases in the filled keg headspace to significantly affect the concentration already in the beer.

If you spund to carbonate, then you will be left with more of the trace volatiles, then if you vented at close to atmospheric pressure.

Brew on :mug:
 

doug293cz

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Hi Doug
Its been about an hr. Oops, I had the spunding valve on. What pressure should I set it to?
Was considering connecting another keg from my blowtie, but since I don't know what I'm doing might reconsider, lol 😆
The higher the pressure setting on the spunding valve, the longer it will take to push the liquid from one keg to another. Unless you are trying to deliberately pressure ferment, I would leave the spunding valve at 5 psi or less for about the first half of fermentation. After that, I would set the pressure to whatever your carbonation chart/calculator says you need for the final target carb level at the temperature you are fermenting. If you have a good way to monitor your SG during fermentation (like a Tilt, or similar), then you can wait until you are about 5 points above your expected SG to go to the full carb pressure.

But since you are fermenting in a glass carboy (at least it looks like glass in the pic) you should probably not pressurize it more than 2 - 3 psi. Those things are not pressure rated. If it is actually a PET (plastic) carboy, then higher pressures should be ok, but you will probably be limited by the pressure at which the airlock blows out of the top of the carboy.

Brew on :mug:
 
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MugsWorth

MugsWorth

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Ahh, thanks. It's glass so I'll set the psi at 2or so. I just want it to push the sanitizer from 1 keg to the other.
 

AlexKay

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For any volatile substances that come out of the beer during fermentation, they come out because the beer is already saturated with that substance, at the partial pressure of that substance in the headspace. If you are just purging kegs with the fermentation CO2, then almost all of that CO2 (and trace gases) are displaced from the keg when it is filled with beer. There won't be enough of the trace gases in the filled keg headspace to significantly affect the concentration already in the beer.

If you spund to carbonate, then you will be left with more of the trace volatiles, then if you vented at close to atmospheric pressure.

Brew on :mug:
Ah, so the pros want to use captured CO2 to force carbonate (not spund) and volatiles are a problem then. Makes some sense.
 
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