Hello. Due to the restriction in our draft lines (long draw, possibly 5/16 ID?, insulated glycol chiller) we are forced to push our beer with 20 psi in the serving tanks. We are using 100% CO2 in the headspace to push. We carbonate our beer to the 2.6-2.7 range. Our cooler is around 37-40F. We are finding that any of the slower selling styles are absorbing too much CO2 and are a pain to pour after a few weeks. obviously over time the co2 in the headspace is absorbing into the beer at that pressure and temp.
can we use a blended gas of some sort in the headspace to slow down this process without affecting carbonation or dispense?
we run a liquid co2 tank and nitrogen system. the blender has a blend running to our guest keg lines but not the brites. forgot what the blend % is.
Todd G Hicks
BeerDenizen Brewing Services
Serda Brewing Company
(Brewery-In-Construction) - Finally!!!
unfortunately no $ to really install 30 beer pumps at this time. hoping to adjust gases instead, itd be an easy quick fix.
We have access to 'cellarmix' in Australia, which is a nitrogen and CO2 blend. the Nitrogen won't be absorbed by the beer so you can run it at higher pressures without overcarbing.
Not sure if you have access to such a product though?
you can use a mixed gas for pushing but the exact mix you need will vary based on the pressure you need to keep on the tank and partial pressure you need to keep the beer carbonated.
Based on what you're saying I'm guessing the standard blend of 60%N2 40%CO2 won't have enough CO2 in it to keep the beer carbonated throughout the entire serving tank and you'll end up with flat beer instead of overcarbed beer. If you can get a custom blend from your supplier that may work, otherwise you'd need to install a gas blender - and at that point beer pumps are cheaper again.
Another option would be to serve your slower selling beers from keg - the individual kegs aren't on long enough to get overcarbed.
i think that sends me in the right direction. i'll talk to my gas supplier and see what they recommend. im pretty sure they can custom blend or i'll just run it through a blender
Nitrogen blends will also be lighter in the cylinders as it's gas form not liquid (CO2 liquid) so more bottle changeovers required. Good luck.
You can have them dial in your blender to your specific needs.
Run your blender to your bright tanks. You might need a nitrogen generator depending on your volume. You can lease these machines I believe.
Looking at a carboation chart 2.6-2.7 volumes at 38-40 degrees should be about 13-14 PSI for equilibrium. Its a very easy calculation to figure out how much mix you need at the higher pressure. Since you need 20 PSI to push your beer you need to use a partial pressure of CO2 of the proportion between the two. 13.5/20=.675 so you need 67.5% CO2 and the rest Nitrogen to push the beer and keep the carbonation you want.
thanks for all the guidance. it'll be nice to put less beer down the drain.
Beer pumps will do far more to solve your problem than any gas mix will. There is a considerable difference in the height the beer must be lifted between a full and nearly empty serving vessel. The pressure needed to push the beer from the bottom of the vessel will be higher than that required when the vessel is full. A beer pump placed low relative to the vessel level will solve this entirely, and allow you to use only the head pressure required to maintain your carbonation.
Terminal Gravity Brewing,
`+1 for beer pumps.
Phillip Kelm--Palau Brewing Company Manager--