Regulating stil

[C2H6O]

Hello all,
I'm new to this site and very green at brewing, so would like to throw out a few questions and get some advice. So a couple of years ago i had a friend build me a reflux still which is heated using a two ring gas burner. The column of the still is about 1m high and is filled with glass marbles.. So it has lived in my garage for a few years and i decided the other week to finally put it to some good use. I have run 2 washes through both turbo yeast and wasn't terribly impressed with the taste so i will be evolving to a TPW which from what i can read on here is a significant improvement.

I have been doing a lot of reading on the operation of the still however i still have questions. Firstly is temperature, so when i get the thermometer at the top to 80 c i try to level it out, however i do find that it is fluctuating some so i have been playing with the water flow throughout the process to maintain this 80c, my last wash 22l wash produced 4L of 87% product (i discarded the first 200ml to be conservative), the last 2L didn't smell as clean as the first. From what i have read people separate there cuts according to temp am i playing with my water to much? should i just leave this alone when i originally level at 80c?

My next questions is really about product, really i would like to know is 87% a reasonable output or should i try to refine my still??

Thanks for reading, this site has been an amazing help so far, hoping i can contribute back one day..

[Kimbo]

Hi c2 can you post a pic of your rig?
That way we can better understand what features it has :handgestures-thumbupleft:

[blond.chap]

Hi mate,

It would be helpful if you could put up a picture of your still, as it's not clear how it is controlled (LM, VM, CM).

Definitely take a loot at Kiwi's guide to cuts in the newbies corner, taking cuts is the only way to get a good product.

As far as controlling the water temperature at the top (I assume this is what you're talking about), you may be better off letting it do its thing, constant fiddling generally causes problems. However it's hard to say much more without knowing how your still is controlled.

87% alcohol is quite low, so you'll be getting quite a lot of flavour from the wash (won't be particularly neutral), get a picture up and people will be able to help you get that value up.

[C2H6O]

Hi thanks for the quick reply guys.. Here is a pic of my rig, not very good quality sorry, it the only one i had on my phone..

[blond.chap]

Yep, so it's a CM, unfortunately these are known to be a bit tricky to operate. Were you able to get full reflux with this thing (where all vapour generated in the boiler is being condensed with your coolant line)?

If you can get full reflux, then operate it as follows:
1. Set to full reflux for 15 minutes (you'll know when to start the 15 minutes because the column will get hot just below the coolant input).
2. Using small increments turn down the coolant flow, then wait, turn it down a little more and wait etc. When you can feel the column above the coolant line heat up stop adjusting and wait for flow out of the product condenser. You want to run it as slow as possible for the first 200mL (collecting foreshots).
3. Once you've got the 200mL, you can either leave it there and collect like that through the run, or you can turn down the coolant a little more to collect faster (too fast and you'll get low abv).
4. Once you have a good output rate, leave the ball valve alone and collect your cuts (as per guide in newbies corner).

If you still get low abv, or if you can't get full reflux in the first place, you'll need to modify the still to get proper neutral.

One other thing, the thermometer at the top looks like it's held in place with a rubber bung (I think), if so you'll likely get off flavours (and maybe poison) in your drink. Look at replacing with a copper end cap.

[C2H6O]

Thanks mate,
Hopefully this doesn't sound to stupid but im a touch confused with full reflux so i'll try to explain what i had occurring. Oh but firstly at the top of the still is a copper cap with a hole drilled in it for the thermometer, the thermometer is in a rubber stopper, but i guess that the steam does come in contact with this over a very small area. The first run i had a lot of stem coming out the sides of the copper cap so i called the process and fixed this by wrapping the outside of the column with teflon tape and putting the cap back on. On this first run the output was about a drip a second. The second run once everything was heated (i turned the water on after i reached 80c) the output was a lot quicker and i had steam output into the collection container as well, when i turned up the water this stopped though. The output on the second run was a bit strange as it was a quick drip and then a bit of a squirt.. I have only been tasting the output as i want to refine the process to ensure everything is safe before i really start enjoying it
Thanks for the advice on how to operate it more efficiently, i will definitely give this a go

Cheers

[blond.chap]

Cool, a quick fix would be to wrap the rubber stopper in a few layers of plumbers tape (PTFE), which is good and inert.

'Reflux' is a term that means "vapour that has been turned back to liquid to run back down the column". Full reflux is when all of the vapour that is coming up the column is converted back to liquid and goes back down the column. You can make it run at full reflux by turning the coolant water up really high so that no product comes out.

The reason that you run at full reflux first is that it lets the volatile compounds (methanol, acetone) concentrate just under the coolant feed, then when you slowly turn down the coolant you let the bad stuff leave the still so you get better product out later.

The reason that I say to make small adjustments and wait is that when you change your coolant feed, the still takes a while to adjust to the new rate. This is the sequence of events:
1. You change coolant rate
2. The reduced coolant fed through the column lets more vapour past (going to the product condenser)
3. The water in the product condenser increases in temperature (because condensing the product releases heat into it)
4. The water coming out of the product condenser through the bottom of the column gets hotter, this means that less cooling is provided to the column overall, so the amount of vapour going to the product condenser increases
5. This then lets more vapour go to the product condenser and the cycle of points 2. to 5. repeats for a while.

The practical result of this is that a small change in the ball valve, can take the still up to 5 minutes to fully adjust. If you make multiple changes too quickly you'll get really unstable results.

[C2H6O]

Thanks again blond.chap I really appreciate all the advice.
I have a better understanding of the process now. Just so I’m 100% (Have been looking into CM stills and a majority of the pics show the water entering through the bottom) I have the water entering through the top is this OK?

Also my packing material (marbles) come all the way up to the T junction (between column and product condenser) is that correct?

Once again this information has been extremely helpful, will start a wash tonight, am looking forward to the results.

[blond.chap]

Thanks again blond.chap I really appreciate all the advice.
I have a better understanding of the process now. Just so I’m 100% (Have been looking into CM stills and a majority of the pics show the water entering through the bottom) I have the water entering through the top is this OK?

Also my packing material (marbles) come all the way up to the T junction (between column and product condenser) is that correct?

Once again this information has been extremely helpful, will start a wash tonight, am looking forward to the results.

No worries mate, glad to help.

Unfortunately, the cooling line setup on your still head isn't ideal. You'd be best off having coolant feeding into the bottom of the product condenser, otherwise you don't get efficient cooling (as you saw with vapour coming out of the the PC). However it would be better to have coolant feeding into the top of the column and out of the bottom one (otherwise you'll get a lot of reflux heading straight to the boiler, without passing over the packing.

If it condenses the product ok with the lines feeding into the top run it like that. But if you start getting vapour out then shut it straight down and switch the lines (safety first and ethanol vapour is pretty unsafe).

The best thing you can do as a first improvement project is to switch the coolant lines over so that the initial feed goes into the top of the column, goes out into the bottom of the product condenser, then goes out of the top of the PC into the bottom of the column.

As far as the packing, anything above where the coolant feeds in at the top won't be doing anything. But it won't hurt it either.

Good luck with your run tonight, take a look at the take 5 checklist in the newbies corner before you start, safe distilling is fun distilling.

[SBB]

Has that still even got a reflux condenser in it, or is it relying totally on those two pipes going through the column for reflux, I got a feeling it is.

[blond.chap]

Has that still even got a reflux condenser in it, or is it relying totally on those two pipes going through the column for reflux, I got a feeling it is.

That's what I figured, and why I'm not sure whether it can get full reflux. If it can't it's more of a hybrid pot/reflux.

[C2H6O]

Ok so reflux condenser, is this a coil of copper pipe in the column that chills the marbles? No my still does not have this, it only has those two tubes that pass through the column, is this an issue?

[blond.chap]

Ok so reflux condenser, is this a coil of copper pipe in the column that chills the marbles? No my still does not have this, it only has those two tubes that pass through the column, is this an issue?

As long as it can give you full reflux, it will work as a reflux still and you should be able to get something fairly neutral (if you run slowly enough).

There are a few options for how you can modify it into a more efficient design (new reflux condenser, add a coil at the top and either a gate valve (turn into a VM) or slant plates and a needle valve (turn into an LM). But you can get to that after getting some product out of the thing.

[crow]

Yeah I saw this design yrs ago If its the same the pipe is slighlt crimped down in the middle of the column and drips on to the marbles, to get anything close to reflux it would need to run ever so slow , basically a hybrid. Not a great design but I think they were pretty common up until the late 70's at least (they work to a fashion)

[C2H6O]

Ok so I gather this thing is going to need a bit of work, but yes I might try and get something out of it first..
So when I ran it the other day I had quite a lot of water running through it and it was still dripping pretty quick, to slow it down would I need to lower the heat?
Not a big issue but my product the other day was 87%.. I threw away the first 200ml and kept 4l, is this 200ml enough to get rid of the nasties. I did not leave it full reflux at the start, it was actually quite quick. Im not opposed to running it through again just curious>

Cheers guys

[DaveZ]

Yep, less heat will let it reflux better as it doesn't have to cope with so much vapour coming up through the column. You should end up with a higher %ABV product. I'd keep the water flow up and turn the heat down till you've only got a slow trickle, if that, from the product condensor.

The more heat you throw at it, the more crap that'll come over with the product = lower %ABV but more flavour. Depends what you want out of it, but with a TPW you aren't chasing flavour.

[crow]

Ok now I see your problem, you will really benefit from reading the newbies corner. Below is a link to one of the most important posts in there and the answer to your immediate problem
viewtopic.php?f=57&t=2859

[Dominator]

I would think those 2 pipes would not be enough to induce full reflux, but that is only my very humble opinion. Full reflux will help to compress your heads and tails to give you a bigger better hearts cut.

If it were me, for your next wash I would have the water running pretty much flat out and see how much reflux you can get. Then I would play around with your heat input to the boiler. By turning the heat down you should be able to slow down your take off rate to give better fractions and increase your ABV.

From my limited understanding of cuts, while you can use vapor temp/ABV as a guide, your much better off using smell and taste to decide where to cut heads, hearts and tails.

Oh and I think I would change your hoses around so that the supply goes into the bottom and the return goes into the top. That way the PC (product condenser, the one that your distillate comes out of) will have the coldest coolant in contact with the coldest distillate and vice versa, this is the most efficient way to cool and will make sure you don't get any ethanol vapor coming out of your take off pipe. (Not ideal when your using a flame heater)

Edit: posted the same time as Dave Z and crow.

[SBB]

Blond its an old method of building a reflux still,don't think they were ever very successful, most of them had a lot more cooling tubes running right through the column, They come from the same era as when folks used marbles for packing. I know a bloke who still runs one to make neutral......he swears by it......but then he doesn't practice cutting, and his neutral tastes like shit to me. Some people just don't wanna move forward.

I think it would make a better Rum still than a reflux, its really only a pot still with a couple of reflux tubes through the column, dump the ally's out, disconnect one of the reflux tubes, leave the other one hooked up, try running a rum wash through it and make good cuts, keep some white, oak some.......see what you think.
For that matter you could probably leave both hooked up for spirit runs, just unhook both for strip runs.

[MacStill]

I think it would make a better Rum still than a reflux, its really only a pot still

Yep, it will be a pretty good pot still if used that way :handgestures-thumbupleft: