CO2 collection

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Buffers brewery

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I started this thread in @DocAnna thread on CO2 collection using balloons. As my approach doesn’t involve balloons I thought I should start my own thread and not high-jack hers!
To recap....
(Edit: lot of talk about CO2 collection using balloons. I'm looking at using rigid containers to capture sufficient gas that can be drawn back into the FV during cold crash and any excess gas is used to displace Starsan solution from a full PB/keg in order to fill PB/Keg with beer O2 free).

So, my Xbeeriment was delayed a few days, but have just been testing first part of my “apparatus”.

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Bottom left is FV1 full of water with pump connected to pump water up to FV2 front and centre. The fill speed is controlled by controller on the floor. The FV2 has lid fitted tight and 10mm pipe connects it to the small over-flow jar (tucked behind FV2). From the over-flow jar pipe goes to 5 litre paint kettle which is daisy-chained to the second paint kettle. The 2 kettles are connected using dip tubes that run to their bottom. Kettle 2 is vented to atmosphere.

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Kettle 1 is filled (small air space) with water. Pump is turned on to pump water from FV1 to FV2 which displaces the air, simulating CO2 from fermentation. In turn, the air displaces the water from kettle 1 to kettle 2.

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When all the water has been transferred, excess gas bubbles through the kettles and vents (phase 2 of the experiment is to connect the vent to a KK full of water to see if enough pressure can be developed to displace the water from the KK).

To simulate cold crashing, the water from FV2 is drained back to FV1 which creates a vacuum in FV2, drawing the gas out of kettle 1 back in to FV2 and the water from kettle 2 back to kettle 1.

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So, phase 2!
I filled my King Keg to the brim with water and fitted my lid.

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You can just see a small air bubble under the left hand corny post showing keg is full. Even managed to put a reading on the pressure gauge.
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Connected the beer out line to a pipe to a bucket to collect any displaced water, and the gas in post was connected to the vent from kettle 2.

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I started with kettle 2 full of water and kettle 1 empty. Switched on the pump to start pumping water from FV1 to FV2 to pressurise the system and after a few moments bubbles appeared under the lid of the KK and shortly after water began trickling in to the overflow bucket!

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Managed to collect about a gallon of water indicating this could work! Flow is slow, probably due to the liquid out line resistance. I’m going to try increasing the diameter of the silicone float tubing in the KK and shorten the discharge pipe to the bucket to see if that makes a difference but I think the beer post could be a bit of a restriction too. I tried to pump the water a bit faster but only succeeded in popping the lid off of kettle 1! :laugh8:

TBC (To be continued)
 
Hi mate are you selling those king keg lids i relay like them.
thanks Longy.
I have supplied another forum member with some of my lids. I’ve tried to DM you with details but says you don’t exist! :confused.:

Edit: check your Privacy settings to allow members to start a conversation.
 
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Why don't you come straight out of the fermenter with a line, into a receiver, then straight into the King Keg? Also have you got a spunding valve on the King Keg?
 
Why don't you come straight out of the fermenter with a line, into a receiver, then straight into the King Keg? Also have you got a spunding valve on the King Keg?
Hi @foxy That’s what I’m doing only the receiver is full of water at the start of collection. There is a small liquid trap between FV and the receiver just in case there was any carry over from the fermentation. The idea was that by displacing the water there would be a “pure” CO2 collection with no air. I’m beginning to think I’ve made a fatal error in that the CO2 is dissolving into the water as fast as it’s being produced. I say that as there has been no further displacement overnight. Sadly, I think I’m going to declare my exbeeriment a failure asad1. Was fun though.
Regarding the King Keg, had the exbeeriment gone as planned, after the receiver was full of CO2, the two taps would’ve been turned OFF to seal the CO2 in and the “gas in” line to the Keg would’ve been connected so the CO2 could pressurise the barrel and displace the water (that it was initially full of) out of the “beer out” connector, thus filling the King Keg with CO2 as well. No need for spunding valve. Didn’t get that far.
 
You might be worrying a bit about "pure co2" just a receiver empty should be enough to catch anything coming out with the co2, (as long as you don't cap it to early) Then go straight into King Keg, it gives the beer in the keg a better mouthfeel, I don't know why. Why should it be any different to putting a bit of sugar into the keg? But it is. I have seen it mentioned on other forums, one I do recall was on the Pro Brewer site, so it not just my imagination.
Can't find the thread but you can pick up some good information from these guys.
What is the purpose of "Capping" fermentation - ProBrewer Discussion Board
 
Think you're right @foxy . My approach has a fatal flaw. While there is sufficient CO2 produced during the fermentation of 5 gallons of beer to inflate 1 or 2 foil balloons, because I have water in my kit it doesn't work! CO2 is too soluble in water and the relatively slow rate of production gives the gas time to dissolve into the water. For my kit to work I need to find a liquid that will not absorb CO2. Hg! :laugh8:ashock1asad.
 
Yes, I might have to admit defeat. I was trying to see if I could come up with an approach using rigid containers and a liquid (water) to vary the volume, forgetting CO2 is absorbed by water! I think a design review is needed.
 
Hi. You need to to compress it to a liquid state. Want to work together on this?
 

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