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Author Topic: O2 Aeration through Liquid side of Keg Fermenter?  (Read 3689 times)

Offline dcbc

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O2 Aeration through Liquid side of Keg Fermenter?
« on: August 08, 2010, 11:20:58 am »
I've got an oxygen question.  I recently picked up an O2 aeration system.  It came with the regulator, aeration stone, and about 2 feet of 3/8" tubing.  I ferment in a 15 gallon corny keg (tall and narrow).  I was able to get the stone under the surface of the wort, but not by much. 

Has anyone who ferments in kegs rigged something up to add oxygen through the liquid out dip tube.  I would have to ditch the aeration stone to do this, but figure I could get the O2 in from the bottom this way and get better coverage with it bubbling up through the entirety of the wort.  It would also be easier to sanitize since the dip tube is taken care of when I sanitize the keg.

Is there enough pressure on these disposable O2 bottles to push through the dip tube when the volume of wort will be pushing back to a point, so to speak.

Thanks.
I've consumed all of my home brew and still can't relax!  Now what!

Offline gordonstrong

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #1 on: August 08, 2010, 11:48:32 am »
I haven't seen these set up for oxygenation/aeration, but those setups are fairly common for carbonating.  Most people don't carbonate in kegs, so aerating in kegs is much less common than carbonating.

Go to morebeer and search for part KEG445 to see what I mean. 

Maybe you can rig up your O2 tank with a ball-lock connector and you can use this for double-duty.

Or if you already have the parts, you can make something like this yourself. It could certainly be attached to the gas or beer posts of a keg, just use flexible tubing instead of the dip tube to attach the stone.

If you get the keg lid attachment, then you can just switch lids depending on what you want to do and you don't have to mess up your kegs.
Gordon Strong • Beavercreek, Ohio • AHA Member since 1997 • Twitter: GordonStrong

Offline Matt B

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #2 on: August 08, 2010, 12:24:27 pm »
I would just use some flexible tubing to connect it to the dip tube or the gas tube that protrudes an inch or so down, run as much tubing to get the stone as far down as you would like. Of course, this is assuming that the barb on the stone and the tubes are about the same diameter, otherwise you're going to have to get creative. I wouldn't use any clamps as they're usually not SS, and because of that I wouldn't go crazy with the pressure lest you blow the thing off and you've got a useless stone now sitting at the bottom of your fermenter.

Offline dcbc

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #3 on: August 08, 2010, 03:15:20 pm »
Thanks, Gordon and Matt.  The tubing is 3/8".  So I could source more pretty easily to get it to the bottom. 

However, my question is would I loose much efficiency as far as getting O2 into solution by removing the stone from the equation and pushing the O2 down the liquid dip tube in the keg?  That way, I could just throw a liquid disconnect on the tubing in place of the stone, open the valve a bit, and pop it on the liquid post on the keg.  O2 goes to the bottom and bubbles up.  Bigger bubbles, yes.  But must easier to sanitize since it's sanitized anyway.  This is how I carbonate my kegs, though obviously not with O2. 

I guess there's only one way to find out.
I've consumed all of my home brew and still can't relax!  Now what!

Offline tschmidlin

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #4 on: August 08, 2010, 03:27:54 pm »
You will lose a lot of efficiency by removing the stone from your aeration setup. It's all about surface area and contact time - you're increasing the contact time a bit by making the O2 travel further before it breaks the surface, but you're massively reducing the surface area of the bubbles.  I wouldn't do it, but you can certainly try it and see how it works out.
Tom Schmidlin

Offline gordonstrong

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #5 on: August 08, 2010, 03:40:04 pm »
I agree with Tom.  It's likely to be lame.  Use the stone.

If you don't want to use the stone, why not get a mix-stir and a drill and just whip the hell out of it?  If you're not using the stone, you're probably not getting any more oxygen into solution than you'd get by churning it with air.  I have no data to support that, it just seems that way to me.
Gordon Strong • Beavercreek, Ohio • AHA Member since 1997 • Twitter: GordonStrong

Offline dcbc

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #6 on: August 09, 2010, 08:27:53 am »
Thanks for the advice.  I'll get a longer tube and keep the stone in the equation.  I was all set to try the ball lock qd setup, but my fermentation had kicked off and I wasn't going to introduce any O2 at that point.  Those hefeweizen strains certainly don't waste any time ginning up.
I've consumed all of my home brew and still can't relax!  Now what!

Offline gordonstrong

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #7 on: August 09, 2010, 09:16:54 am »
Less oxygen in a hefe will give more esters which is what a lot of people want anyway. Keep temps cool.
Gordon Strong • Beavercreek, Ohio • AHA Member since 1997 • Twitter: GordonStrong

Offline dcbc

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #8 on: August 09, 2010, 08:25:49 pm »
62 and fermenting away.  Finally found a recipe that works and it is really helping beat the heat this summer.
I've consumed all of my home brew and still can't relax!  Now what!

Offline jwatkins56550

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Re: O2 Aeration through Liquid side of Keg Fermenter?
« Reply #9 on: August 09, 2010, 09:05:58 pm »
Ive added oxygen in the keg through the side out with okay results  A wine degasser or paint mixer would work much better, although you could bubble 02 through the dip tube while using a degasser or mixer and greatly increase your amount of dissolved oxygen.