Moonpile said:
My biggest tip for keggles is that the skirt holds a LOT of heat, and it takes an immersion chiller a long time to overcome it. I currently only have an immersion chiller, so what I do is actually lift the keggle off the burner and put it in a Rubbermaid rope handled bin full of water immediately after flameout. The hiss of steam is pretty wild, but it allows the immersion chiller to really do its job. I run the hose into the bin for a few minutes too.
Dude! That's nuts, and
seriously dangerous.
There was a guy on here a few months ago who dropped his kettle while full of near boiling wort and got serious burns. NO ONE SHOULD CONTEMPLATE CARRYING A KEG OF HOT WORT....not even just a couple of feet. It is quite possible to
die from complications resulting from the burns that could be sustained in that activity.
Think about this:
3rd degree burns on the front of your legs and waist (if it were to tip and pour down your front), would have a mortality rate of approximately between 25% to 50%...depending on your age and health. Even at the low end, do you really want to risk being the 1 in 4 that dies....in order to cool your beer faster? I'm not normally given to hyperbole, but I don't think this is the least bit alarmist. It is a VERY real risk with this much water an that much heat.
Ok...warnings aside....from a technical perspective it is also completely unnecessary:
That steel doesn't hold anywhere near as much heat as the water inside the keggle. The heat capacity (pound for pound) of Stainless is 1/8th that of water. So, even if your entire keggle weighted as much as the wort inside it (which it does NOT), the wort would have still have 8 times as much energy in it. Granted the base of the keg can get hotter than the boiling point, so the total heat is elevated by however far above boiling it is. Still, that is ONLY the mass of metal in the hoop of the foot, which might be a couple of pounds at the most. Again your 6 gallons of boiling water has a LOT more heat in it than all of the steel in the entire keg.
Some math, in round numbers:
- keggle weight = ~30 lbs
- Wort weight = ~50 lbs
- Wort specific heat = 1.00 btu / lb / F
- Keggle specific heat = 0.12 btu / lb / F
Assuming you are trying to cool to 70F, you are trying to remove this much heat from each:
- Wort Heat: 1.0 btu/lbs/F * 50 lbs * 142 F = 7100 btu
I don't know how hot the keggle foot can get, but lets assume you could get to 412F:
- Keggle_foot: 0.12 btu/lbs/F * 2 lbs * 342 F = 82 BTU
Now the rest of the keggle at boiling (though the part above the wort will not be that hot):
- Keggle_remainder: 0.12 btu/lbs/F * 28 lbs * 142 F = 477 BTU
So the entire keggle has 550 BTU of heat that has to be removed, versus the 7100 BTU for the wort. The entire keg holds less than 10% of the wort. The foot of the keggle that you are trying to cool holds 1% of the total heat of the system to be removed.
If your wort is not cooling fast enough its because your chiller isn't big enough and/or your water chill water isn't cold enough. I have 50 feet of 1/2 OD copper in my immersion chiller, and I chill to under 100F in 4 minutes. At that point I switch to recirculating ice water and it takes 5-10 more minutes to chill to 70F or so.
Your method is working because you are removing heat from the WORT, its the same as the water bath method that a lot of partial boil / kitchen brewers use. The water in your rubbermaid bin is drawing heat out of the wort...not the steel.