HBT 2014 Big Giveaway - 94 Chances to Win!

Huge Supporting Membership Discounts!
 Home Brew Forums > Oxygenate Wort- what PSI how long

06-28-2013, 01:14 AM   #1
chrisdb
Feedback Score: 0 reviews
Recipes

Join Date: Nov 2010
Posts: 212
Liked 5 Times on 5 Posts
Likes Given: 4

 Oxygenate Wort- what PSI how long

I gave up my medical O2 tanks and regulator that read in CFM and got a 20Cubic foot O2 tank and a pressure regulator that measures PSI to aerate wort.
problem is I can't find any recommendations for PSI setting/duration to properly aerate wort, nor can I find a calculator online that will translate PSI to CFM.
I know there must be plenty of you who are using O2 from welding supply... how are you calculating your oxygenation?

__________________

BlackPtBrewing Likes This
06-28-2013, 06:07 AM   #2
CryoEng
Feedback Score: 0 reviews
Recipes

Join Date: Mar 2012
Location: Rio Rico, AZ
Posts: 96
Liked 12 Times on 4 Posts
Likes Given: 2

You don't "convert" between the two.

Do you have any electrical experience?

Think of pressure as "voltage," mass flow (gas flow) as "current."

The flow rate is dependent on pressure AND resistance.

Put 20 psig on a 3 foot long, 1/16" diameter tube and on a 1 foot long, 1" diameter tube. How do you think the flow rates will compare?

Re-phrase the question, perhaps. (?)

Cheers

__________________

06-28-2013, 10:17 PM   #3
chrisdb
Feedback Score: 0 reviews
Recipes

Join Date: Nov 2010
Posts: 212
Liked 5 Times on 5 Posts
Likes Given: 4

thanks for the response-
I understand there is no direct relationship between PSI and CFM- one is pressure the other is flow.
The 'medical' tank regulator I was using before metered the flow, but the regulator for the welding tank meters the outlet pressure.
What I am hoping to see is someone who is using O2 through an airstone who can suggest a PSI setting and duration through a reasonable length of 1/4 I.D. tubing ...say 4 ft... thru an airstone into 10Gallons of wort. I could probably get a ballpark CFM by blowing up a couple balloons with O2, but that still isn't telling me the most effective PSI to use and duration to get to a target range of oxygenation- say 15-17 PPM.
Also interested to hear if anyone using positive pressure O2 in a venturi is getting better efficiency than an airstone.
I don't brew enough to justify the meters to measure PPM of O2 but I am betting that someone out there is gonzo enough to have done it

__________________

06-29-2013, 12:38 PM   #4
steveoc
Feedback Score: 0 reviews
Recipes

Join Date: Mar 2013
Posts: 91
Liked 14 Times on 12 Posts
Likes Given: 8

I have just ordered this system:

http://www.williamsbrewing.com/BIG-OXYGEN-SYSTEM-P3426C106.aspx

They recommend 1/8 cfm for 1 minute. I don't know how similar or different your set up is, but it might be a starting point.

__________________

06-29-2013, 01:21 PM   #5
chrisdb
Feedback Score: 0 reviews
Recipes

Join Date: Nov 2010
Posts: 212
Liked 5 Times on 5 Posts
Likes Given: 4

That regulator is similar to what I used on my medical oxygen tanks... it meters in CFM. I have a welding style regulator on my tank that measures the pressure (PSI) at the outlet, not the flow (CFM).
It sort of like the diference between measuring torque versus horsepower in a motor...

__________________

06-29-2013, 01:29 PM   #6
JonM
Feedback Score: 0 reviews

Recipes

Join Date: Aug 2010
Location: Milwaukee
Posts: 3,740
Liked 530 Times on 394 Posts
Likes Given: 18

Lots of us just have the little regulator with no gauge on it, so we just turn the knob until bubbles just start to break the surface and let 'er run (through a diffusion stone) for about 20 sec for a 5 gal batch. Maybe some pros can chime in, but most of us just ballpark/eyeball it.

__________________
Sincerity is everything. If you can fake that, you've got it made.

06-29-2013, 01:34 PM   #7
Nagorg
Feedback Score: 0 reviews

Recipes

Join Date: Dec 2011
Location: , Texas
Posts: 372
Liked 41 Times on 32 Posts
Likes Given: 19

Quote:
 Originally Posted by JonM Lots of us just have the little regulator with no gauge on it, so we just turn the knob until bubbles just start to break the surface and let 'er run (through a diffusion stone) for about 20 sec for a 5 gal batch. Maybe some pros can chime in, but most of us just ballpark/eyeball it.
+1 I just kinda eyeball the bubble flow to see a bunch of tiny bubbles instead of larger bubbles. Then I start "1 Mississippi, 2 Mississippi, 3 Mississippi.."

You will see different thoughts around how long to oxygenate. I usually do ~1 minute for a 5 gallon batch.
__________________

06-29-2013, 01:48 PM   #8
chrisdb
Feedback Score: 0 reviews
Recipes

Join Date: Nov 2010
Posts: 212
Liked 5 Times on 5 Posts
Likes Given: 4

thanks.. that is my only option at the moment.
this stuff

makes me want to stick pins in my eyeballs

__________________

06-29-2013, 01:59 PM   #9
Nagorg
Feedback Score: 0 reviews

Recipes

Join Date: Dec 2011
Location: , Texas
Posts: 372
Liked 41 Times on 32 Posts
Likes Given: 19

yeah... Seems like a good place to apply the K.I.S.S. principle!

__________________

07-04-2013, 07:58 PM   #10
chrisdb
Feedback Score: 0 reviews
Recipes

Join Date: Nov 2010
Posts: 212
Liked 5 Times on 5 Posts
Likes Given: 4

Quote:
 Originally Posted by steveoc I have just ordered this system:http://www.williamsbrewing.com/BIG-OXYGEN-SYSTEM-P3426C106.aspx They recommend 1/8 cfm for 1 minute. I don't know how similar or different your set up is, but it might be a starting point.
I too believe in K.I.S.S., which is why I am returning the pressure regulator and have taken delivery on a 0-4 CFM regulator very similar to the Williams product
http://www.emergencyresponderproducts.com/cgoxre.html
for \$24+ \$6 shipping
I already have an airstone, although not the stainless steel wand type that Williams sells... and I think is quite nice, but not nice enough to make me replace what I already have.
and a 20cf oxygen tank that cost \$77 to purchase and \$15 to fill
http://www.weldingsuppliesfromioc.com/catalogsearch/result/?q=oxygen++cylinder+20+cf
all in all pretty happy with the results
but if you are starting from scratch, the Williams package is pretty good

__________________

jungatheart Likes This