Can I set up a Continuous flow small pot distiller from this

[Pissy]

My current SETUP
I have inherited a “Continuous Distilled water still” (2L boiler straight into a condenser, no column), the boiler has 2 separate heat elements (power?) which at the moment are either ON or OFF individually, there is plenty of power even too much for ethanol stilling. The boiler itself only holds 2L,……YES I know its too small but I figure I learn on a this small POT still unit before getting a larger REAL still.

Mine is very similar to this unit


At the moment the still is meant to be a continuous flow system where water constantly refills the boiler as it is been evaporated,……I have disconnected it so it runs like a POT still. I have completed a run from 20L of wash doing 1.5L boiling at a time, (let me tell you all this takes up the whole weekend) I got around 2.5L 65% ethanol, its quite dirty with heads & tails. This first batch is going to be my rough stuff which I will then add a 30cm column packed with ceramic first and then copper saddles at the top with a temp probe between the copper and condenser for the ethanol guessing 79-82C, I also will have a pot fluid and pot vapour temperature probes before the column just for interests.
I am getting an electrician (friend) to make me a power point with a dimmer knob so that I can set ONE of the elements power as it’s just a heating rod and does not cycle and therefore control the boiling better.

Now for my question, due to my current setup, if I were to “try” and set this up as a continuous flow system without the column in place,.. could it work?
I know I would be getting all the heads/methanols etc (Crap),... BUT I will do a 2 second distillation with a colunm as per the normal process to eliminate the heads and tails for a neutral vodka spirit.

When a WASH is heated to “let’s say 78- 85C”, does the ethanol in the solution come to the top waiting to be evaporated as the temperature rises or does it remain randomly scattered in the wash, therefore making this question relevant?
The reason for asking is that I have a waste tap at the bottom of the pot/boiler that can be turn on to empty at the same rate at which I could add more fresh wash and/or ethanol being produced?

I'm hoping that this is not a stupid question


I was thinking that I could maybe do a continuous flow system for the 20-25L of wash in the 2L boiler without the column (plain continuous POT still) and then do a second distillation with column in the normal fashion?
Your thoughts please….

[airhill]

Interesting and pretty
My eyes are not the best but as far as I can see you have no way of getting rid of the waste ie it will continue to build up in the boiler. The amount of higher volatiles in a wash is usually relatively small.

[LWTCS]

By the time you engineered a continous solution that would be presentable to a public forum, you could build a right proper 52 liter potstill and operate it with the supreme confidence that a tried and true solution will render a whole bunch more better likker.

[Pissy]

Until I progress to a better still, I'm stuck with this,.....plus is an interesting way of learning/experimenting.

My boiler does has a waste dump valve at the opposite end of the heating elements along the buttom. I should take a picture when i get it set up again.

As i mentioned before, this continuous still system would only be a means to boil out the 20L of wash instead of doing 15-18 x 1.5L boils as the my boiler only holds 2L.
I spent 10hours (2 x 5 hours over a weekend) standing by the still watching the temps, emptying waste wash and refilling it, getting up to temp, distilling and repeating this over and OVER again.

Making it continuous would be a far easier but I am unsure if it will work.

I will be doing a second "proper" run with a column to get the nasties out.

[airhill]

Pissy

I had another look at it, it would have to be a batch load run. In a CF you would normally load from part way up a column with vapour coming up either from steam or an overflowing boiler with liquid lock, as the wash descends through the rising vapour the volatiles are boiled off and ascend the column by the time the wash has reached the bottom it has given up a lot of its ethanol.
In your situation you are unlikely to be able to tell at what speed you should fill and drain as the boiler will continually be in a part wash part waste situation.

[olddog]

I spent 10hours (2 x 5 hours over a weekend) standing by the still watching the temps, emptying waste wash and refilling it, getting up to temp, distilling and repeating this over and OVER again.

If you have to keep refilling it, it aint a continious still.

[blanikdog]

A valid point OD.

blanik

[rad14701]

That was my thinking, too, olddog...

[Pissy]

OK I get the point too guys,.......
If set up properly for water its continuous but for ethanol is not really possible?

What if I dribble in fresh wash while I open a valve at the bottom of the boiler at the same rate for removing waste wash(I am hoping that the ethanol has risen to the surface of the boiler and left dead wash on the bottom) .

Sorry if its confusing?

[airhill]

The topic gentlemen was a question, not how Pissy currently runs it

Just seen your post, it doesn't work like that unfortunately (I wish it did)

"If set up properly for water its continuous but for ethanol is not really possible?" I'd put that as highly improbable

[olddog]

I would not be wasting my time with that unit, just build a proper still and be done with it.

OD

[airhill]

I would not be wasting my time with that unit, just build a proper still and be done with it.

OD

I'm with olddog on that one Perhaps a flavour still for small runs or testing, but very difficult on anything else. Looks as if it was designed for a lab to produce distilled water and thats what it would be good at.

I'd keep it, but I have a fondness for interesting glassware.

[rad14701]

I have to agree, as well, that this unit probably isn't worth investing much time and effort into... However, for the sake of science, or whatever you want to call it, there is a way to make the still continuous, even for alcohol...

Yes, you would run new wash in continuously but you would need to gauge the in-flow accurately so as not to waste precious alcohol...

As far as the out-flow, that needs to take place at the boilers optimal fluid level... This can be achieved by attaching a tube to the bottom valve and having it rise to where your boilers optimal fluid level should be... It is important to use this method because it is the only way to insure proper wash level within the boiler, eliminating both flooding and boiling dry... This would also allow you to monitor the alcohol content in the waste water to insure that you are extracting as much alcohol as possible from the wash...

In fact, this would be the best place to monitor the continuous still because you can't actually regulate the %ABV of your distilled and condensed product anyway... Wash in-flow would be regulated to keep the waste water at as low of a %ABV as possible for a given amount of heat input... You would keep the waste gate wide open and regulate the still using wash in-flow...

So, if you are going to proceed down the continuous still path, using this rig, that is how you should proceed... Also remember that with a continuous still you cannot make proper cuts so you will need to use a batch still to clean up the what the continuous still produces... This is also why continuous stills aren't used more widely for making small scale potable spirits...

And one final note regarding safety... While you may be working in a lab environment many of us don't... And because we don't work in lab environments the use of glass becomes a potential hazard to the point of not being recommended for home distillation... NUFF SAID...

[Pissy]

I think rad14701 has got a great point about the waste bottom valve/hose bend being at optimal fluid level, as you said at least this way I don't over or under fill the boiler but I would need to be precise with the flow rate of fresh wash into the boiler,........Why didn't I realize that

I know its not a good,..in fact its a bad setup/system but I am only trying to play around with what I got,..........its a hobby,....I'm not going to stress about it
I'm interested in seeing how much if any %ABV is left in the waste/draining wash thence my original question about ethanol rising to the top of the wash when in a boiler at 79-82 degree C?

I'll give it a run with 25L wash and see what I get,......worst case is $5-10 out of pocket and a touch wiser (I doubt it)

[goinbroke2]

If you look at the way a continuous still operates, the idea is to introduce the new wash high enough that the hot vapour accending around it will heat it and strip the alcohol out. The alcohol then rises where it can be taken off. the only liquid not vaporising is water (in theory) and when it gets to the bottom you just drain the hot water off.

What you are attempting is a potstill that as the alcohol is distilled out you top it up with new wash. One noted problem is the amount of backset left over, the second is how to drain the low alcohol backset and not the new high alcohol wash. As far as I know, no the alcohol does not "rise to the top" of the wash in the still. And yes that is the problem in your case.

What to do? Well, I think I fall into the "do it right the first time" crowd. A guy I knew was rebuilding a 49 willy's jeep. He pulled the running 6cyl flathead out and threw it in the corner. He was dropping in a 58 or something will's motor that had a number of improvements. He was going to throw the old motor in the scrap because he had no use for it! Holy crap I said, it's a perfectly good engine! I'll take it! It's been in my garage taking up space for over a year now. Lots of idea's and what if's.....
My point is, sometimes a white elephant is just that, a white elephant which will distract you from doing what you should of in the first place. You'll dick around and fiddle and fart and finally get so frustrated you'll either throw it away and build a proper still and regret the time you wasted on it, or you'll get pissed off and forget about stilling all together as you've already wasted too much time and your interests have changed.

It's a neat rig. It probably destills water great. use it for that.

[Dnderhead]

save it to distill water, that will become handy later for diluting.

[The Baker]

If you look at the way a continuous still operates, the idea is to introduce the new wash high enough that the hot vapour accending around it will heat it and strip the alcohol out. The alcohol then rises where it can be taken off. the only liquid not vaporising is water (in theory) and when it gets to the bottom you just drain the hot water off.

snip

Thanks for that, goingbroke2.

Yeah, I knew that's how a continous still worked but now I more or less UNDERSTAND it. Great.