Sorry if this is the wrong spot to post this, seemed like the most appropriate. I am reading my tail off and trying to understand theory, but of course every time I think I understand I realize there’s something obvious I’m missing.
Last night I did a stripping run on Jimbo’s all grain. Two inch pot still column from Brewhaus, attached to keg. Got to about 184 and started seeing vapor. I love this still but their O-ring to keg system is crap. Of course I shut it down and fixed the problem. By the time I got it fired back up it had dropped to 179. In my simple little mind, there should be nothing coming off since I had already reached 184. In other words, it seeems to me that everything that’s going to boil off from 179 to 184 already would have, and that I should have to wait to 184 to see any output again. But it pumped it out pretty steady right at 179.
Why is this? What am I misunderstanding? And, yes, I know I shouldn’t rely on a thermometer. I’ve gone from staring at it the whole time to just checking it three of four times. Hard to go cold turkey.
Thanks in advance.
Theory question
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Re: Theory question
fractions don't boil off at magic temperature points. you are only able to control the rate of the boil...thats why temperature is just an indication of shit happening, not exactly what shit is happening.
i.e. water boils at 212* (at sea level) no matter how much heat you pour into it, it will be 212*. what changes is the rate of boil. so somewhere below 212* you may see evapouration which is liquid water in suspension. not much, but a little. increase heat and when you reach 212* you have phase shift from liquid to steam steam is transparent. the temperature of the water remains the same. if you increase heat enough the water will flash boil,or phase shift entirely to steam and the pot is empty. the cloud of liquid water vapour above is the steam losing energy (heat) and phase shifting back into water liquid suspended in air.
so it's just simply the rate of takeoff that changes, not the components of the vapour itself
you don't mention where the temperature was taken, but i suspect at the top of the column. once all was heated up it produced at what seemed to be a lower temperature simply because the mass of the whole wash, and all the metal involved was still reaching an equilibrium throughout..
the first time you got to 184 because a lot of other shit was still warming up to operating temperatures.
in reality the vapour temp was likely above 190 at that point, but the metal and t-meter was still warming. there's a chart here somewhere for that shit if you need the science.
i.e. water boils at 212* (at sea level) no matter how much heat you pour into it, it will be 212*. what changes is the rate of boil. so somewhere below 212* you may see evapouration which is liquid water in suspension. not much, but a little. increase heat and when you reach 212* you have phase shift from liquid to steam steam is transparent. the temperature of the water remains the same. if you increase heat enough the water will flash boil,or phase shift entirely to steam and the pot is empty. the cloud of liquid water vapour above is the steam losing energy (heat) and phase shifting back into water liquid suspended in air.
so it's just simply the rate of takeoff that changes, not the components of the vapour itself
you don't mention where the temperature was taken, but i suspect at the top of the column. once all was heated up it produced at what seemed to be a lower temperature simply because the mass of the whole wash, and all the metal involved was still reaching an equilibrium throughout..
the first time you got to 184 because a lot of other shit was still warming up to operating temperatures.
in reality the vapour temp was likely above 190 at that point, but the metal and t-meter was still warming. there's a chart here somewhere for that shit if you need the science.
I finally quit drinking for good.
now i drink for evil.
now i drink for evil.
Re: Theory question
That’s some good shit right there. Thank you.HDNB wrote:..thats why temperature is just an indication of shit happening, not exactly what shit is happening.
Re: Theory question
yup, i knows my shit.
did i mention my ole Lab shit on the floor while i was out today? may have something to do with having written shit like 12 times.
i'd beat the rest of the shit out of him, but he's so damn old he's earned the privilege of the occasional oops poops.
did i mention my ole Lab shit on the floor while i was out today? may have something to do with having written shit like 12 times.
i'd beat the rest of the shit out of him, but he's so damn old he's earned the privilege of the occasional oops poops.
I finally quit drinking for good.
now i drink for evil.
now i drink for evil.
Re: Theory question
Shit, man. That’s some bullshit. Thanks for helping me sort shit out.HDNB wrote:yup, i knows my shit.
did i mention my ole Lab shit on the floor while i was out today? may have something to do with having written shit like 12 times.
i'd beat the rest of the shit out of him, but he's so damn old he's earned the privilege of the occasional oops poops.