Odd question…

Distillation methods and improvements.

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Biff_McNielly
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Odd question…

Post by Biff_McNielly »

How many of you have to actually see a still run to completely get it? I read about distillation until I was blue in the face before I was ever brave enough to try it. A basic pot still is simple enough but even then there is a lot of minor adjustments that takes some learning that can have a big impact on how it runs and your final product.

As I’ve begun reading and learning about the many other types of stills I seem to get lost. I am a very mechanically inclined person and can look at something and duplicate it without a problem but that doesn’t mean I fully understand what is going on. Some of the column designs I’ve seen simply don’t compute in my head and I would imagine if I could stand there and watch one run the light bulb in my brain would finally turn on lol. I will say that learning about reflux columns has been by far the most difficult thing ever. Maybe I’m over thinking it? I saw one where it has a vent in the top next to the dephlegamator so it’s open to the atmosphere. When I first saw it I couldn’t wrap my head around it because that seemed to go against everything I’ve ever known with a pot still.

I’m currently saving cash to buy myself a nice reflux set up. But that’s a conversation for a different day. In the meantime I’ve cobbled together a column for my existing kettle to see how different things I’ve seen and ideas work since it’s not like we can just run down to “Stills R Us” and look at demo models. I’m wondering how many other people here have had the same hard time figuring different still types out.
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Dancing4dan
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Re: Odd question…

Post by Dancing4dan »

Hey Biff.

If you have someone who will let you see their still run it will help immensely. I don't actually know anyone who is operating a still and didn't have the benefit of doing any observation. Bit of a steep learning curve but I built a small pot still first. Ran it multiple times before I started to look at other systems. Not sure, but it sounds like you have not run a pot still yet. If you haven't, do that a few times then the other concepts become much clearer.

You actually learn a lot from the two cleaning runs. During the vinegar cleaning run I shut off the supply water to the product condenser to develop a steam jet, then turned the supply water back on to condense it back down to a trickle. THIS WAS DONE OUTSIDE OF COURSE. It is informative to see how much steam the condenser is knocking down.

Once the pot is boiling and you only have a small stream of liquid coming out of the product condenser it will start to fall into place in your head.

Building your own is a far better option than buying in my opinion.

Be safe. Search and read a lot, then ask questions when you don't know.
"What harms us is to persist in self deceit and ignorance"
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Saltbush Bill
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Re: Odd question…

Post by Saltbush Bill »

I agree , the reading and thinking can get daunting......wading in and getting hands on often makes all the reading make sence.
Take care what you buy in the way of a reflux still....there are some pretty crappy designs out there.
LM,CM,VM and CCVM....all work quite differently.
CM are the only ones not open to atmosphere at the top of the column, they are open via the product condenser.
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Salt Must Flow
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Re: Odd question…

Post by Salt Must Flow »

Biff_McNielly I say pick a design that peaks your interest and I'm sure the mechanics can be explained pretty easily.

Let's take this VM (Vapor Management) design for instance. It has a tall column and the column is completely full of packing. Upon heatup, the gate valve is closed. Once the boiler heats up enough, vapor rises up the column and meets the reflux condenser coil on the very top. Notice that the very top is vented. Once the vapor reaches the reflux condenser the vapors will condense and rain back down. Vapor will constantly be rising, condensing, raining down and the most volatile vapors will soon accumulate to the very top as the column stabilizes. There should be a thermometer probe in that reducer just before the gate valve so you'll see when the temp stabilizes. Once the column is stable, you crack open the gate valve just a bit. A small amount of vapor is allowed to leave the column, enter the product condenser, it condenses and exists as cool 60F product which you collect. Over time you can open the gate valve a little more and it will come out faster. It's really that simple.

VM 3 in Example.jpg
You will want a digital thermometer that reads 1/10th degree resolution because that's the range in which all the temp changes take place during a spirit run. I'm really partial to the VM design for its simplicity of operation and it is not sensitive to fluctuations in water pressure/flow. It runs perfectly stable and all you have to do is open/close a valve. Other reflux column designs rely on physically raising & lowering the reflux coil instead of using a valve CCVM. Others may use a dephlegmator below the vapor takeoff and dephlegmators are really sensitive to water flow/pressure fluctuations (I don't like these types much). LM (liquid management) stills are pretty easy to understand. They're somewhat like VM where instead of opening a valve to let a little vapor out, you open a little valve to let a little liquid product out.

Reflux columns must be vented because if you accidentally shut the water off it literally becomes a bomb. Most make this mistake on occasion and hears vapor escaping out the top.
tombombadil
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Re: Odd question…

Post by tombombadil »

I still have a lot to learn but thinking about it while watching it run certainly helped clear some stuff up.
Nothing like hands on experience!
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Yummyrum
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Re: Odd question…

Post by Yummyrum »

Saltbush Bill wrote: Thu May 26, 2022 2:38 pm
LM,CM,VM and CCVM....all work quite differently.
CM are the only ones not open to atmosphere at the top of the column, they are open via the product condenser.
Just to expand on that a bit .
CCVMs are also always open to the atmosphere via the product condenser.

Although they are also vented at the top , is not a safety requirement as in the case of LM or VM , but rather because of the way they operate , IE , the coil has to lowered or raised .
They end up vented as a result .
drmiller100
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Re: Odd question…

Post by drmiller100 »

Saltbush Bill wrote: Thu May 26, 2022 2:38 pm I agree , the reading and thinking can get daunting......wading in and getting hands on often makes all the reading make sence.
Take care what you buy in the way of a reflux still....there are some pretty crappy designs out there.
LM,CM,VM and CCVM....all work quite differently.
CM are the only ones not open to atmosphere at the top of the column, they are open via the product condenser.
I believe all stills should have an opening to atmosphere for us amateurs.
Pressure can kill.
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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Saltbush Bill
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Re: Odd question…

Post by Saltbush Bill »

They all are.......or if not should be.
drmiller100
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Re: Odd question…

Post by drmiller100 »

Saltbush Bill wrote: Sun May 29, 2022 12:14 pm They all are.......or if not should be.
My apologies. I misread your post but now I get it.
Now I know how you claim azeo so easy, it's based on a meat thermometer. :lol:
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