Column Temperature

[ZAXBYC]

Ok I'm in the process of my first decent run.

I am currently attempting to equalise the column.

The temperature was fluctuating between 78.0 and 78.7 and is now 78.2-78.4 is this normal for a run or is something else causing the fluctuation?

Im thinking that condensate might some how be involved, but if this is normal then I suppose I don't have anything to worry about!

EDIT: My current thinking is this might have something to do with factions setlling down in the column. Comments?

[rad14701]

How long had you let the column attempt to reach equilibrium before becoming concerned...??? A minimum of 15 minutes, and up to a couple hours, is not uncommon... Once it's there, the temperature should stabilize... Things like coolant flow or heat input can cause these fluctuations, but if they are steady then just wait to see if things settle... Shouldn't take long as you've probably already discovered while waiting for a reply...

[ZAXBYC]

Right so it appeared to have stablised, afer 45 minutes, so I decided to crack open the tap.

After 70ml the temp plumeted from 78.3 to 77.6 and stopped there for ages. What caused this?

I decided to slowly increase the heat, and got it to 78.2, after 125ml it went up to 78.3. The first collection was 91% this collection was 94%

the Following 125ml is 95%.

the collection rate began to drop so I upped the heat again. The thermometer is at the top of the packing , but about 4inchs from the actual take off.

the temp is now a stable 78.4 and the follow 125ml was 95% too.

I suppose no still is the same to another so you do really have to learn it.

[HookLine]

Once the column is equilibrated, the temps should be quite stable (allowing for the normal increases as you go through the different early cuts). Once you get into the hearts in particular, the temp should sit rock steady right up to near the end of that cut, usually on about 78.2-78.4C. Mine doesn't even vary a tenth of a degree through the hearts cut (given constant weather conditions).

I suppose no still is the same to another so you do really have to learn it.

Yes, but once you know it well, it should be much the same each run. (Again, allowing for different weather conditions.)

[minime]

Ok I'm in the process of my first decent run.
I am currently attempting to equalise the column.
The temperature was fluctuating between 78.0 and 78.7 and is now 78.2-78.4 is this normal for a run or is something else causing the fluctuation?
Im thinking that condensate might some how be involved, but if this is normal then I suppose I don't have anything to worry about!
EDIT: My current thinking is this might have something to do with factions setlling down in the column. Comments?

Don't know it this will help but I ran into this problem a while back on the inverted funnel build. It turned out the temperature probe did not have the sensor in the tip of the probe. It was actually about 4cm back from the tip so all I had to do was shove the probe in a little farther and bingo. Most of the hardware is pretty cheap consumer grade stuff without any kind of quality control.
Just an idea..........

[ZAXBYC]

Weather shouldn't be an issue for me, the temp ranges from 12C-19C.

Just increase the temp again, running at 78.5 now just to see what the output is for it. <- what I look like at the moment!

I think the sensor is at the tip... it seems to react the quickest there

[HookLine]

Weather shouldn't be an issue for me, the temp ranges from 12C-19C.

It isn't ambient temperature that is the issue, it is barometric pressure. It can vary the boiling temp. Same effect as changing altitude.

But sounds like everything is running fine for you now.

[ZAXBYC]

I suppose I just like to try and understand what im doing.... if I do x it will cause y to happen becuase... etc.

I am never happy unless I know why changing x affected y !

[minime]

Weather shouldn't be an issue for me, the temp ranges from 12C-19C.

It isn't ambient temperature that is the issue, it is barometric pressure. It can vary the boiling temp. Same effect as changing altitude.

Yup, I never go by the actual temperature but base all my adjustments from the final temperature at equalization. From my observations it can go up or down by 1/2 degree Celsius on barometric pressure. Wonder what would happen if a big cold front moved in during a marathon run

[rad14701]

I haven't seen here what your take-off rate has been set to... If you are taking off spirits faster than the boiler is making them then your column temperature will rise... A common misconception is that the temperature would fall but a reflux column doesn't work that way... It's entirely possible that while you were managing to attain an equilibrium you simply weren't pushing enough heat to maintain the take-off rate you chose to use... This would also explain the unexpected drop in ABV... More heat or slower take-off rate will usually resolve the issue... It'll take a few runs to find the sweet spot where your still runs consistently stable... Sounds like you're well on your way... You deserve that moment of

[ZAXBYC]

Ok I just tried some, and I know I haven't let it air yet, but this stuff has a burn to it and isn't quite as neutral as I would have hoped.

when I watered it to to cira 40% I notices the swirls in the water and Kinda knew it wasn't going to be as good as I first hoped.

what has happened here, temp was about right but I have fusels in the product!?

The smell reminds me of something.... I just cant but my finger on it, sweetish almost medicinal?..... ok kinda aniseedish by smell i suppose

[ZAXBYC]

INFO:
I am pretty certain the condensate is not falling back into the column and it is all heading out the take off

The run has varied between 7ml/min to 120ml/min ....just me playing about....The boiler is running between 1000 and 1600W respectively

The sample i refer to in the above post was taken at 50ml/min came out at 94% @20C

[rad14701]

That fluctuation in take-off rates is probably part of why you got that mdedicinal off-taste... Nothing to worry about as long as you're not tasting fusels... Hey, if you don't like the final product, just make sure it's diluted and run it back thought so you can learn more without waiting for another wash to finish fermenting...

[ZAXBYC]

When I rubbed it between my fingers it was slightly oily.... damn these things aren't straight forward at all!

[minime]

damn these things aren't straight forward at all!

Aw, but they are............you're just being impatient. Slow your takeoff rate to a crawl and watch your hydrometer sink to the bottom and THEN taste. You'll be quite amazed I'm sure.

You'veGotToFindYourGrooveMinime

[eternalfrost]

when I watered it to to cira 40% I notices the swirls in the water and Kinda knew it wasn't going to be as good as I first hoped.

tht is nothing to be worried about. it will ALWAYS happen.

it is because water, and high proop ethanol have such different densities (just look at the effect it has on a hygrometer!) things with different densities generally have very different indices of refraction. this is basically a factor that describes how mych light refracts (bends) when changing mediums.

anytime light passes from one substance to another, some will reflect and some will refract. this is the basic principle behind prisms.

anyway, long story short. when you mix them, you get little sections of high and low refractions which makes light passing through it bounce around.

this is exactly what makes mirages work. the hot air just above the road has a different index then the ambient air(its much hotter and less dense) this curves light that would normall just hit the road upwards back into your eye, making the "mirror" effect

[maoule]

Ok I just tried some, and I know I haven't let it air yet, but this stuff has a burn to it and isn't quite as neutral as I would have hoped.

when I watered it to to cira 40% I notices the swirls in the water and Kinda knew it wasn't going to be as good as I first hoped.

what has happened here, temp was about right but I have fusels in the product!?

The smell reminds me of something.... I just cant but my finger on it, sweetish almost medicinal?..... ok kinda aniseedish by smell i suppose

Relax, the swirls happen every time you mix high proof w/water; some kind of reaction (don't remember what it's called) that generates a little heat. Remember also if your distillate temp will affect the abv reading. I'm re-running all my "neutral" (about 2.5gal of 60%) right now using the real slow method; the shit is coming off real gooooood. The abv is holding steady @ 93.5-94 and 13C. The column equalized at 77.7c and wandering now between 77.6 & 77.8c, which in my case is "normal".

[ZAXBYC]

Minime, I'm afraid you might just be right, lol I for some reason though 34ml/min was slow..... thats like 2l an hour

I was being inadvertantly impatient

I shall re run it REAL slow

Like a small kid I tells you!

Thanks for the heads up on the oily effect!- you know I learn something new every day... I think today is making up for the rest of the year!

[Hawke]

You said your takeoff rate was fluctuating? Sounds like you are having a syphoning problem. I had this problem on mine. If you install a vent right after the valve, you will be able to get a more consistant flow.

[ZAXBYC]

You said your takeoff rate was fluctuating? Sounds like you are having a syphoning problem. I had this problem on mine. If you install a vent right after the valve, you will be able to get a more consistant flow.

Nah that was me playing with temp and the valve

I can achieve a stedy droplet rate, if I open the valve up more so it becomes a trickle, I think i suffer the syphon effect then.

[ZAXBYC]

Hawke, Do you mean here?



This is the head in pot mode btw (without column attached, I am running it with it attached atm!)

[ZAXBYC]

Ok I listened, worked out I had max of 1 litre of ethanol left in the still.

I turned the temp up a lettle to get some forced reflux going, and turned down the drips.

The column stablised at 79.3C and I got some non oily stuff off at 95% @20C

Then on the last bit....bang temp sarted rising abour 0.1C every 10secs.... guess the tails are coming then!

Thanks for all your help guys. I cannot wait to run this thing properly tomorrow, slow and not greedy wins the race!

[Hawke]

Yes, that is the correct location for the vent. On mine I used a 90 degree elbow and drilled an 1/8" hole in the top. A tee fitting would also work. For a straight line, just point the branch up. For a 90 degree turn, go from valve to branch.

[rad14701]

I've found that for anything but a stripping run I have to force myself to run the still slower than I might want... It definitely requires a measure of restraint as you have discovered...

Kinda like keeping a fast car under the speed limit... Sure, it'll go 140 MPH, but that's 85 MPH over the speed limit... Sooner or later it's gonna come back and bite you in the ass...

[ZAXBYC]

Kinda like keeping a fast car under the speed limit... Sure, it'll go 140 MPH, but that's 85 MPH over the speed limit... Sooner or later it's gonna come back and bite you in the ass...

How'd you know about that?!