23 l plastic carboys for vacuum degassing/transfer

[WVMountaineerJack]

That is exactly what is needed, plus a good pump, is it on ebay? WVMJ

A bit overkill, but something like this.

 

[WVMountaineerJack]

What is the wall of this thing made of, a big piece of pipe? WVMJ

 

[stickman]

There are a number of units available on ebay, they look like a restaurant grade stock pot with an acrylic top modified for all of the fittings. These type of units have been traditionally used for casting resin degassing. Do a search for that and you'll find everything you need and more.

 

[vacuumpumpman]

There are a number of units available on ebay, they look like a restaurant grade stock pot with an acrylic top modified for all of the fittings. These type of units have been traditionally used for casting resin degassing. Do a search for that and you'll find everything you need and more.

I did do that - very interesting and all -
thats alot of work just to keep plastic carboys instead of glass. I appears that most units that large - you would have to lift the full carboy and placing it in the vacuum chamber. This is seems alot of backbreaking work just in order to use plastic -= IMHO

But keep us posted on your results

 

[sour_grapes]

I think it worth pointing out (not inspired by anyone in particular) that the OP (Ric) runs a pretty sophisticated U-Vint operation:http://www.winetimefactory.com

As he stated in the first post, he has a large number of plastic bottles, so the effort to find a way to degas them may well be worth his while. Ric, you HAVE a vacuum pump capable of going to low pressures. Have you tried using it on your new project?

 

[rhattin]

Happy new year folks, a little update on the degassing system. Got the big bugs worked out and now able to get about 10 psi pressure differential. The neat thing is that I can degas and transfer all 3 carboys at the same time in about 3 minutes. I think that is too fast to get all the dissolved CO2 out. My research indicates that the acceptable limits for co2 is between 1000 to 300 mg/l, depending on whether it is red,white or spritzer. My research also shows that there are few home winemaker test instruments, at least reasonable ones, for CO2 concentrations.
Now I am going to venture into chemistry with some intrepedation: the fermentation process generates a lot of CO2, almost a litre of gas per litre of wine, at 20 degrees C. Since it is generated internally, I assume that the wine is completely saturated with dissolved CO2 at STP, and using a solubility coefficient of .704 molar fraction at 1 atm, indicates that there is about 20 l of Gas dissolved in 23 l of wine. As we all know, the remainder blows off throu the air locks.
If I was able to reduce the pressure to 1/2 atm, then the solubility drops to .34 molar fraction and should release about 10 l of CO2 at STP and get sucked out by the vacuum system.
So 10 l is .446 of a mole, or 19 gms of gas in 23 l, or 826 mg/l. And that seems to be a reasonable target concentration.
Well, what's the conclusion?
Does this concentration level make sense? Will this shorten the ageing time. Is wine in 2 weeks now possible? I hope not.
Some neat pictures to follow
Ric

 

[rhattin]

Well, we now have two versions of the plastic carboy degassing system: one that will do 1 carboy at a time and the other which will do three. Got almost all of the bugs worked out of the vacuum vessels and can draw the max that the pump will suck, which is about -25 in Hg, or -12.5 psi. Does that ever get rid of a lot of gas and quickly. The expensive bit is the 1/2 in plexiglas , otherwise time and making your router perform is the hard part. Have installed a similar system at a local U-Vint operation and the wine makers love it. Better than standing around for 5 minutes with a drill and fiz-ex. . Now to sell it to other shops!
Ric