Keg still tower design questions

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fafrd
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Re: Keg still tower design questions

Post by fafrd »

Cu29er wrote:.

I read your post and then skimmed the other responses but here are some things to consider:
Appreciate the post, Cu29er. Some comments:
Cu29er wrote: -Keep the still simple. Make a standard 'pot still' and compare running your material through once vs twice. Get an idea how it all works. There are a lot of variables to sort out. A three foot column and two to three foot chiller will work.
This is pretty much my plan. I was going to start with a short pot-still column of ~12" since I thought I understood there is little benefit to a taller column in a pot-still. Chiller will have ~17" of twisted CSST-Dimroth into the end of 2" pipe that will be longer tha that.
Cu29er wrote: -Boka style is needed to get very high % proof out, however they are more difficult to run (like driving your car with one foot on the gas and the other on the brake).
If/when I get into higher proof, I was planning to start by using my still in CCVM-mode with reflux. Boka's are beautiful but seem much more complicated to build.
Cu29er wrote: -Your kitchen or stilling location will determine your still size. If you are doing it on a conventional kitchen stove you may have cabinets above that restrict how tall your column gets.
I'll be outside (propane burner), so height shouldn't be a concern.
Cu29er wrote: -Packed columns can be dangerous. If your pot pukes or starts to while running and you don't notice it could plug your column then you're over there wondering why the column temp isn't going up and the lid clamps crack open spraying you with sticky scaling fluid. Six weeks and scars. Start with an open column and plan for two runs to boost the proof.
I appreciate this warning. Was not planning to explore packing until I'm much more experienced (if ever), but I'd like to understand enough about it to plan my CCVM build properly. After this warning, when I get around to trying reflux/CCVM, if will be without packing at first. Any interest I may have in higher-proof spirits and/or greater efficiency/speed will be quickly washed-out by doing anything that significantly increases the danger index...
Cu29er wrote: -Get an Ikea or similar meat thermometer and make a probe point at the top of your column before the condenser, you can set 170F alarm to know when it's heated up and watch the fore shots, set other alarms to know where you might want to take a split or to shut it off at say 210F as you know it's out of proof.
As I am sure you are aware, there are many opinions on the Forum about the value of thermometers ;). I was planning to monitor return temps of PC coolant (CSST-Dimroth condenser) to have an idea of what was 'going on' but since I have a capped column, adding another thermowell anytime to as far below the product port as I'd like. I have a number of thermocouples and have made many thermowells for my beer-brewing, so this is almost 'for free' for me and I was thinking about doing so anyway at the start just because I am a curious sort. Your input has reinforced that intention.
Cu29er wrote: -Column height is more important than the condenser length. If you make the condenser the same length or nearly so as the column you should be ok. A taller column gets you higher proof. If too tall you hit the kitchen ceiling.
When you say that (in bold), you mean in reflux-mode, correct? There is not any strong reason to increase column-height of a pot-still, right?

My pot-still will be a keg with a 12" column into a 2" capped stainless T, so about 4' tall sitting on my propane burner. The 2" CSST-Dimroth PC will probably also be ~4' long.
Cu29er wrote: -install a needle valve to control the cooling water flow rate, the sink faucet handle is too crude.
[/quote][/quote]
Appreciate this suggestion. Have not had any exchanges about coolant control yet. My plan for cooling is to use a submerged pump in a large tank of coolant (10-20 gal of water) and to monitor both coolant return temps and tank temps. If needed, I can add ice and/or coldpacks to cool coolant back down. I have ball valves and clamp valves that I use to reduce pump flow to a trickle all the time, so I can do that to coolant flow if needed.

I thought control of coolant flow was only needed for the redlux condenser and that coolant should be run flat-out for the product condenser (with a tank; water wastage could be a problem using tap water).

Thanks again for the suggestions.
Last edited by fafrd on Wed Jun 20, 2018 10:37 am, edited 1 time in total.
fafrd
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Posts: 114
Joined: Wed Jun 06, 2018 9:25 am

Re: Keg still tower design questions

Post by fafrd »

zapata wrote:At the bottom of each page is a "bookmark topic" button. Why dont you bookmark the topics you have found most helpful / least referenced both so far and as you learn more? At some point you'll no longer be a brand new beginner, but your bookmarked threads could be a good reference to share. It's kind of a hard thing for experienced members to do and your fresh eyes and willingness to research could help the next round of beginners.
I did not know about that bookmark feature, thanks.

As I continue down the rabbit-hole, I will do that.

I know exactly what you mean about the value of "fresh eyeballs" and will do what I can to capture the jewels my eyebalks discover while they are fresh ;).
OtisT
Master of Distillation
Posts: 3185
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Location: Pacific Northwest

Re: Keg still tower design questions

Post by OtisT »

fafrd wrote:
Cu29er wrote: -Boka style is needed to get very high % proof out, however they are more difficult to run (like driving your car with one foot on the gas and the other on the brake).
If/when I get into higher proof, I was planning to start by using my still in CCVM-mode with reflux. Boka's are beautiful but seem much more complicated to build.
A boka is not required to get high proof. You can get the same high proof from a properly run VM, CM, or LM style fractioning still. You are OK with your VM plan.
fafrd wrote:
Cu29er wrote: -Get an Ikea or similar meat thermometer and make a probe point at the top of your column before the condenser, you can set 170F alarm to know when it's heated up and watch the fore shots, set other alarms to know where you might want to take a split or to shut it off at say 210F as you know it's out of proof.
As I am sure you are aware, there are many opinions on the Forum about the value of thermometers ;). I was planning to monitor return temps of PC coolant (CSST-Dimroth condenser) to have an idea of what was 'going on' but since I have a capped column, adding another thermowell anytime to as far below the product port as I'd like. I have a number of thermocouples and have made many thermowells for my beer-brewing, so this is almost 'for free' for me and I was thinking about doing so anyway at the start just because I am a curious sort. Your input has reinforced that intention.
If you are curious, add the thermomports. I highly recommend you observe the thermometer (for curiosity sake) but don’t try to drive your pot still by temp. You have one control on a pot still, the power/heat input to the boiler. The only thing you need to measure/monitor during a pot still run is the product output: takeoff rate (volume/time) and ABV. If you do add the thermometer and you do hit 170F at the takeoff, you are running way too hot to pull foreshots properly. You would already know this because your takeoff rate would be way too high. By the time you back off the heat to reach a proper takeoff rate of 1 to 2 drops per second, your vapor temp will be in the 150s and 160s F and will slowly increase from there.
fafrd wrote:
Cu29er wrote: -install a needle valve to control the cooling water flow rate, the sink faucet handle is too crude.
Appreciate this suggestion. Have not had any exchanges about coolant control yet. My plan for cooling is to use a submerged pump in a large tank of coolant (10-20 gal of water) and to monitor both coolant return temps and tank temps. If needed, I can add ice and/or coldpacks to cool coolant back down. I have ball valves and clamp valves that I use to reduce pump flow to a trickle all the time, so I can do that to coolant flow if needed.

I thought control of coolant flow was only needed for the redlux condenser and that coolant should be run flat-out for the product condenser (with a tank; water wastage could be a problem using tap water).

Thanks again for the suggestions.
In my experience, you are correct fafrd. You can’t have too much PC cooling going on, unless conserving water is your mission. I use a ball valve on my PC just so that I can conserve water. I try to only use enough water so that my product output is just cool. On stripping runs or other runs when I don’t want to measure ABV output, I am OK with warm product output.

You can have too much reflux cooling for some operations, so when you get there I agree that a needle valve on your RC would be a good thing.

Otis
Otis’ Pot and Thumper, Dimroth Condenser: Pot-n-Thumper/Dimroth
Learning to Toast: Toasting Wood
Polishing Spirits with Fruitwood: Fruitwood
Badmotivator’s Barrels: Badmo Barrels
fafrd
Bootlegger
Posts: 114
Joined: Wed Jun 06, 2018 9:25 am

Re: Keg still tower design questions

Post by fafrd »

OtisT wrote:
fafrd wrote:
Cu29er wrote: -Boka style is needed to get very high % proof out, however they are more difficult to run (like driving your car with one foot on the gas and the other on the brake).
If/when I get into higher proof, I was planning to start by using my still in CCVM-mode with reflux. Boka's are beautiful but seem much more complicated to build.
A boka is not required to get high proof. You can get the same high proof from a properly run VM, CM, or LM style fractioning still. You are OK with your VM plan.
That's what I thought but appreciate the confirmation.
OtisT wrote:
fafrd wrote:
Cu29er wrote: -Get an Ikea or similar meat thermometer and make a probe point at the top of your column before the condenser, you can set 170F alarm to know when it's heated up and watch the fore shots, set other alarms to know where you might want to take a split or to shut it off at say 210F as you know it's out of proof.
As I am sure you are aware, there are many opinions on the Forum about the value of thermometers ;). I was planning to monitor return temps of PC coolant (CSST-Dimroth condenser) to have an idea of what was 'going on' but since I have a capped column, adding another thermowell anytime to as far below the product port as I'd like. I have a number of thermocouples and have made many thermowells for my beer-brewing, so this is almost 'for free' for me and I was thinking about doing so anyway at the start just because I am a curious sort. Your input has reinforced that intention.
If you are curious, add the thermomports. I highly recommend you observe the thermometer (for curiosity sake) but don’t try to drive your pot still by temp. You have one control on a pot still, the power/heat input to the boiler. The only thing you need to measure/monitor during a pot still run is the product output: takeoff rate (volume/time) and ABV. If you do add the thermometer and you do hit 170F at the takeoff, you are running way too hot to pull foreshots properly. You would already know this because your takeoff rate would be way too high. By the time you back off the heat to reach a proper takeoff rate of 1 to 2 drops per second, your vapor temp will be in the 150s and 160s F and will slowly increase from there.
Yes, I had understood that (not trying to control pot-still by temp). You've helped to understand the benefit of monitoring temps at the product port. If too high, more ethanol is being mixed with the foreshots so a cleaner cut-off is impossible. Monitoring/controlling take-off rate is another technique to achieve the same, but take-off rate is a lagging indicator, so monitoring temps at product port is a quicker way to know when you're getting into a problem zone (which can be done 'by hand' with experience).
OtisT wrote:
fafrd wrote:
Cu29er wrote: -install a needle valve to control the cooling water flow rate, the sink faucet handle is too crude.
Appreciate this suggestion. Have not had any exchanges about coolant control yet. My plan for cooling is to use a submerged pump in a large tank of coolant (10-20 gal of water) and to monitor both coolant return temps and tank temps. If needed, I can add ice and/or coldpacks to cool coolant back down. I have ball valves and clamp valves that I use to reduce pump flow to a trickle all the time, so I can do that to coolant flow if needed.

I thought control of coolant flow was only needed for the redlux condenser and that coolant should be run flat-out for the product condenser (with a tank; water wastage could be a problem using tap water).

Thanks again for the suggestions.
In my experience, you are correct fafrd. You can’t have too much PC cooling going on, unless conserving water is your mission. I use a ball valve on my PC just so that I can conserve water. I try to only use enough water so that my product output is just cool. On stripping runs or other runs when I don’t want to measure ABV output, I am OK with warm product output.
Thanks for the confirmation. I'm just starting to read about cooling solutions (and just book-marked my first thread on that subject ;)).

Using tap water is safe and using a valve to limit water wastage is smart. I'm hoping to use a resevoir with a pump but have now understood the dangers associated with pump failure in the middle of a run. So I'll probably rig up some kind of flow-sensor and alarm or even gas shut-off valve if I go that route...

I appreciate the confirmation that during stripping runs I can run the product condenser flat-out.
OtisT wrote: You can have too much reflux cooling for some operations, so when you get there I agree that a needle valve on your RC would be a good thing.

Otis
Good to know - I'll put a needle-valve on my long-term distiller's shopping/salvaging list ;).

It also seems to me that in reflux mode, there is still no disadvantage to running the product condenser flat-out.

If correct, this would be an argument in favor of parallel connections to RC and PC compared to the series connections I see many rigs use. Parallel would allow you to control the coolant flow as aporopriate into the RC while allowing all remainibg coolant pressure to flow flat-out through the PC...
OtisT
Master of Distillation
Posts: 3185
Joined: Sat Oct 24, 2015 11:59 am
Location: Pacific Northwest

Re: Keg still tower design questions

Post by OtisT »

+1 to Parallel flow controls.
Otis’ Pot and Thumper, Dimroth Condenser: Pot-n-Thumper/Dimroth
Learning to Toast: Toasting Wood
Polishing Spirits with Fruitwood: Fruitwood
Badmotivator’s Barrels: Badmo Barrels
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