Deflag. Condenser Placement

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Craddosk
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Deflag. Condenser Placement

Post by Craddosk »

Looking for more information on deflag. condenser placement, specifically with regards to CM stills.

Curious if on a still like Brewhaus produces (CM), where the column splits in two. Is it possible/wise to place a deflag. condenser between the two column portions (essentially in the middle) in order to more effectively force reflux? Would a 4" condenser be sufficient for running on propane?

Doing some rough calculations, on the bottom 18" x 2" column section, there's approx. 900ml (1/4 gallon) of volume. Being that a typical 10% wash for 5 gallons would product aprox. 2l (0.5 gallons) of pure ethanol, would reflux in such a small space not be effective? Or would any vapour that did condense simply fall back into the boiler?

Main reasoning behind this is not only to increase purity, but to strip the flavour out as well. I ran an All Bran wash and ended up with a wheaty product when tempered down to ~40%.
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skow69
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Re: Deflag. Condenser Placement

Post by skow69 »

Curious if on a still like Brewhaus produces (CM), where the column splits in two.
How about a drawing or picture?
Distilling at 110f and 75 torr.
I'm not an absinthe snob, I'm The Absinthe Nazi. "NO ABSINTHE FOR YOU!"
Craddosk
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Re: Deflag. Condenser Placement

Post by Craddosk »

skow69 wrote:
Curious if on a still like Brewhaus produces (CM), where the column splits in two.
How about a drawing or picture?
Think essentially this:

http://www.brewhaus.com/Essential-Extra ... Still.aspx" onclick="window.open(this.href);return false;" rel="nofollow

You can see in the photo where the ferrules connect.
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skow69
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Re: Deflag. Condenser Placement

Post by skow69 »

A reflux condenser should always be located above all the packing such that the reflux enters the packing at the very top. You would be better off to replace those cross tubes with a dephlegmator.
Distilling at 110f and 75 torr.
I'm not an absinthe snob, I'm The Absinthe Nazi. "NO ABSINTHE FOR YOU!"
Craddosk
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Re: Deflag. Condenser Placement

Post by Craddosk »

skow69 wrote:A reflux condenser should always be located above all the packing such that the reflux enters the packing at the very top. You would be better off to replace those cross tubes with a dephlegmator.
Under ideal circumstances, I agree with you. But if I was to go to that extent of work, I'd be building a whole new column with the features I desired instead of tearing apart my current set up.

I'm thinking, based on Rad's apartment still VM still, the concept should work...
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Still Life
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Re: Deflag. Condenser Placement

Post by Still Life »

I see your All Bran came out wheaty.
Is that a consistent problem?

CM's can be a devil to pilot.
Are you tired of the learning curve or just have the modification bug?
Craddosk
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Re: Deflag. Condenser Placement

Post by Craddosk »

Out of the two times I've run it, it's come out wheaty I've got a third batch to run but need the weather to improve first.

I'm definitely still on the learning curve on how to get things working properly and getting the desired results, but have a bit of the modification as well. Part of that is driven to learn how to run a deflag. and part wanting to get a better neutral from the learning process.
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Still Life
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Re: Deflag. Condenser Placement

Post by Still Life »

Not to hijack this thread since you did get an answer already.
But I've seen where some Brewhaus PSII owners replaced the touchy stock water valve (for the column only) with a more precise needle valve with great results.
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corene1
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Re: Deflag. Condenser Placement

Post by corene1 »

Not real familiar with that set up but have you tried to run your wash then dilute it back down to 40% with water and re run it slowly. This should pull flavor from the spirit without modifying your present still. Also, how much and what type of packing is in the column?
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cranky
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Re: Deflag. Condenser Placement

Post by cranky »

I'm with Corene on this one. It sounds like you are trying to make neutral in a single pass. This will not strip all the flavor, especially with a cross tube dephleg. I would first recommend doing a stripping run, dilute to 30-40% then run it again and you should get a good neutral. If it still isn't neutral enough for you after that consider putting a better reflux condenser on top, maybe a shot gun and I think the problem will be solved.
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skow69
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Re: Deflag. Condenser Placement

Post by skow69 »

Purity is all about the height of the column. Actually, the height of packing that is refluxed onto, and the amount of reflux created. It sounds like you have discovered that you can't achieve full reflux at your preferred power setting. You could try reducing power to the point where you can hold full reflux and letting it stabilize there for a time, but that will have limits. If you can't go any higher or improve on the cross tubes, I would go the multiple pass route. You don't need to stop at two. Many of us triple distill for neutral. You can run it as many times as necessary and, with your still, it will probably continue to improve with each pass. You will lose a little volume each time also, but that is the price you have to pay. There is no free lunch.

Anyway, the best you could do with an extra deflag at mid-column, would be to change from partial reflux to full reflux for that bottom 18 inches. I doubt it would make a dramatic improvement. You could try better packing. SPP and lava rock both worked better than scrubbers for me, and many people report good results with marbles. Also, I think most novices pack the column too loose. More packing is better, up to the point where it restricts the column. I used to stuff scrubbies in as tight as I could and never had a problem.
Distilling at 110f and 75 torr.
I'm not an absinthe snob, I'm The Absinthe Nazi. "NO ABSINTHE FOR YOU!"
Craddosk
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Re: Deflag. Condenser Placement

Post by Craddosk »

Thanks for all the information! Looks like the multiple pass is going to be my best option, as column height can't be increased and I can't get full reflux with the cross tubes.

Packing is a mixture. The bottom 18" is raschig rings with the top 18 inches (roughly, as it stops at the top of the cross tubes) is packed in copper. Back to playing with the still to see what I can improve!
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