Product percentage

[dave]

In my reflux stil I've done a couple of washes using Still spirits turbo express yeast to get an output of approx 3.5 litres @ 75% alcohol. According to Still spirits website this is about right for their yeast. I have read about stills producing 93% alcohol and was wondering if anyone has any ideas as to whether I am doing something wrong or how to get the percentage of alcohol upto 93%, do I need to do a different wash?

[LWTCS]

Gotta put it through your still twice.

Run once, dilute back down to 40% then run it again.

[ScottishBoy]

You haven't given enough parts of the equation to solve for the answer. We need to know what type of still (sounds like you might be running a store bought) you are running etc.
But if I were to hazard a guess from what you said here, It sounds like your are running too fast.

I'm not going to give you the turbo speech( you will ditch them soon enough), but I will suggest more reading...

[dave]

Made it from a 30litre 3000 watt urn, 2" stainless pipe column approx two metres tall with condenser off from the top on an angle down. Packing height of 150mm of stainless pot scurrers. Three cooling pipes passing through column from condensing tube in top 500mm of column.

[LWTCS]

Made it from a 30litre 3000 watt urn, 2" stainless pipe column approx two metres tall with condenser off from the top on an angle down. Packing height of 150mm of stainless pot scurrers. Three cooling pipes passing through column from condensing tube in top 500mm of column.

Do you have any controll over your input or just plug it in and go?

[rad14701]

Just to clarify, it is the sugar, not the yeast, that determines the amount of alcohol in the wash... Then the distillation process determines determines the amount and proof of the resulting spirits...

[dave]

There's the heat dial on the urn so you have some control of the element.

[rad14701]

There's the heat dial on the urn so you have some control of the element.

You don't attempt to control the temperature of the wash, the ratio of water to ethanol does that... You need to do a bit more research into the theory of distillation in general as well as how to operate a pot still... You'll get there...

[WalkingWolf]

You haven't given enough parts of the equation to solve for the answer.

No part of the answer here but I do remember telling my professors that so many times in college. Brought a shudder. I better fix me another drink as I feel post-traumatic stress disorder starting to act up.

[seravitae]

Dave,

Urn element heating controlls are thermostats, and are generally rubbish for temperature control.
Also don't give up on turbo yeasts, they have their uses, you can read my mini-review on turbo yeasts, pro's and cons in another recent thread here.

Your still type (based on your suggestions), while technically it refluxes, is more commonly known as a fractionating still, as your fractionation column is air-cooled. In order to make yours a reflux still (by common convention) you would require either a secondary condensor at the top of the fractionation column (prior to the angled condensor), or, a completely different layout using one condensor (the nixon-stone offset style stills which you can see on homedistiller pictures).

While your still will definately work, it is a common belief that having a large fractionation column will lead to higher reflux ratio and purity, (assuming no auxillary condensor), if you crunch the numbers, you find that the bulk of the fractionation column often can be entirely useless when compared to the performance of a still with a small fractionation column and a second condensor.
If its possible, I would cut off the top of your fractionation column (so you remove the angled condensor) and weld/solder a nixon-stone head on top, with a needle valve. You will get very impressive results. I have a 1" non-packed 30cm air column (terrible!) with a nixon-stone offset head regulated by a needle valve and i can easily pull >90%.

[dave]

I'll try and get a photo attached to make it easier to see my explaination. Might make it bit easier to visually see my still.

[dave]

Here's a picture of my little toy

[Ayay]

Aarh... coolant management. Hard to drive because it all depends on adjusting the coolant flow. 100% Reflux is probably not achievable, but it must be done in order to get a base line. With no base line you are somewhere between a pot and a reflux still. Run the heat real slow and adjust the coolant as possible.

Really nice setup you have there! It will deliver once you find a way to run it to the max; and the max is not just ABV...it's also the flavour, cuts, and ageing as the pot stillers will testify.

[ScottishBoy]

Tinker, Tinker, Tinker....get results....

Lather, Rinse, Repeat...Its gonna take a while, but you will find the sweet spot. When you do, you will be a happy man.

[rad14701]

Although kiwistiller noted that cooling management stills are not all that efficient, which is entirely true, you could probably improve performance by installing a thermometer port between the top coolant tube and the top of the column... A thermometer placed there will allow you to monitor the temperature of the vapor that is headed to your product condenser... If you can dial the still in at 78C/172F you'll be able to collect cleaner neutral spirits and/or adjust for a specific amount of flavor... Adjusting heat input and coolant flow will get you where you need to be... Also, don't discount the idea of future modifications in order to attain an easier to run design...

[dave]

With this being coolant management, I was reading some other posts about vapor management. Does the column have to be open at the top, cause I was wondering if I was to put a valve/tap at the top of column before it goes to the condensor to restrict the flow of vapour, but am concerned about pressure build up in the column. Any thoughts or maybe start from scratch on that design? Has anyone tried this before?

[Ayay]

If you converted your still to VM by adding a coil condenser on top and a vapor valve just before the leibig, then the coil on top is open to the atmosphere and the vapors to the leibig can be closed off with no chance of pressure build-up. You are correct, the still must never be allowed to pressurize. It must never even be capable of being pressurized.

Rad's suggestion of adding a thermometer in the vapor path at the top of the column is the most ecenomical mod. It will be a big help in driving your still as it will tell you what's happening when you adjust the coolant through the cross tubes and the heat level in the boiler.

There are previous posts on converting a CM like yours into a VM. No need to hurry, your still will work!

[Ayay]

Here are some results from a search of 'cm to vm' in this forum
http://homedistiller.org/forum/viewtopi ... m#p6835001
http://homedistiller.org/forum/viewtopi ... t=cm+to+vm
http://homedistiller.org/forum/viewtopi ... m#p6827626
http://homedistiller.org/forum/viewtopi ... m#p6826832

Your still will pump out 80%+....somewhere between a pot and a reflux and there's a whole lot of good happening there. Severe cuts will get you drinkin after a week of airing. Generous cuts need some ageing.

I tried pot stillin a few times a year ago. Couldn't drink any of it immediately and went back to the LM but I did put away a gallon of rum. Now a year later ageing in glass it is very nice rum! Mmm, them pot stillers are on a higher level. (The quality experts and not the bootleggers).

A CM is somewhere in-between. Read up on both pot stillin and refux stillin and figger it out

[dave]

So much info on this site and so easy to get side tracked, (few long neck bottles home brew, coupla home bourbans) and then forgotten what you started looking for. It was mentioned earlier on
Urn element heating controlls are thermostats, and are generally rubbish for temperature control.
what type of control is best for element control?
Also I tried running the leibig and the cooling tubes in the column(another condensor i guess) on seperate water circuits and seemed to have better control, added digital thermometre to top of column and lastly bought some insulation from plumbing shop and insulated entire column. First litre collected was 90% abv then about 60% towards the end so got an average on three and a half litres at 80%. So it was a bit better, but could always be better.
Try, drink, fall over, try again.

[LWTCS]

what type of control is best for element control?

You need something that will not allow the element to cycle.
Steady input is best.

It is not about the boiler charge temp as such.
Wash temp will change as the alcohol within the charge gets depleted.

Will your rig go into 100% reflux mode with a fresh(cool) supply of water?

[dave]

How can you tell if it is in 100% reflux. No output? Get a little bit confused.

[LWTCS]

How can you tell if it is in 100% reflux. No output?

yes

[dave]

Thanks for that. And if it doesn't go 100% then look at different condenser or more cooling tubes? Are water jackets or cross pipes through column better?

[LearJet]

Assuming you built that yourself you must be handy with the tig welder. If that's the case if it were mine I would get rid of the cross cooling tubes, cut the top of the column open, stick a copper wound condensor coil in the top, and add a gate valve between the column and the product condensor. Then you have a Vapor managment column. Way easier to run than your current setup. If your really handy look into adding a set of slant plates just below the column condensor with a needle valve to remove fores, heads, and tails. That way you don't get stinky spirits in your product condensor. I recently converted my column to VM and I am about to tear her down again to add slant plates. I always seem to learn something new right after I finish improving my rig and then I have to have that too.