Building a 2” stripper pole

[Steve Broady]

This is the beginning of a 2” continuous stripping still. All the copper is the effluent side, with a 16” long 3/4” over 1/2” heat exchanger. I’ve got drains for both the heat exchanger and the effluent, and a fitting to add a thermometer right beside the column to monitor the temperature of the effluent. The union serves a dual role, both making it possible to break it down into relatively linear components, and to rotate the outlet in order to adjust the water level over the heating element.

Speaking of the element, it’s a 5.5kW 1.5” triclamp unit. That makes it a handy backup for my keg boiler, but more importantly it means that when run on 110V it’s just under 1500W. The plan is to be able to run this more or less anywhere that has electricity. No need for special electrical service. Also no need for cooling water, since the incoming wash is going to be doing the job of condensing the vapor.

Not shown, I’ve got a peristaltic pump to feed the cleared wash into the system, and about 4’ of 2” TC spools and marbles to fill them. My plan is to run about 3’ of marbles and 1’ empty above the wash inlet for foaming control.

Still to purchase, aside from various fittings, tubes, and other miscellaneous items, is a product condenser. My hope is to have it all together in a couple months. If this thing works as planned, it will make stripping wash a LOT more convenient. I’ll still use the pot still for the spirit runs, but I’ll be able to run this in the garage where I do my fermentation.

[NormandieStill]

Watching this with interest. A few questions:
Have you done any maths to determine flow rates or expected abv?
What kind of reflux head (I assume that there's some reflux happening if you've got a packed column)?
Will your wash also be cooling the reflux head and / or pc?

[Yummyrum]

Also no need for cooling water, since the incoming wash is going to be doing the job of condensing the vapor.

Cool project Steve .
Yes it cqn be done …… but oh my god it is a critical balance .

Yhat was my ultimate goal when I had a crack at it but , while it is doable , I would suggest adding an Auxillary PC to deal with the periods …. That will happen…. When it does not run right and un condensed vapour comes out the spout .

Oh it will .

[Bolverk]

Based off the 408w pg/ph we've seen posted and the 1375w (25% of the 5500w) he should be stripping right around 3.37 gph (12.75l)

[GrumbleStill]

Will be watching on in interest Steve.

Hope it goes well.

[Steve Broady]

Have you done any maths to determine flow rates or expected abv?

I’m leaning heavily on advice from Bolverk. In fact, this whole thing is inspired by conversations with him and the realization of how convenient it would be. I’ve got a 0.5 L/min pump with speed control, which I’ve tested as being able to deliver 425 ml/min at full speed. My guess is that I’ll be running a bit below that at full power.

I’m not sure about the ABV. Since I’ll use this for stripping, I’d be quite happy if I can get 30% average. My guess is that it will be capable of a bit higher, but we shall see. No idea yet how that will impact flavor.

What kind of reflux head (I assume that there's some reflux happening if you've got a packed column)?

There’s no reflux head, since this isn’t meant to be a reflux still. Preheated wash goes in at the top, meets the vapors coming up from the bottom, and is ideally devoid of all its alcohol by the time it’s at the bottom.

Will your wash also be cooling the reflux head and / or pc?

Yes, the cold wash will feed the PC, and then (maybe) go through the heat exchanger on the effluent pipe. I say maybe because I’m not sure how much of a difference it will make, or if it might cause issues with overheating and boiling the wash prematurely. If that’s the case, I’ll just bypass that and run the effluent HX dry.

Based off the 408w pg/ph we've seen posted and the 1375w (25% of the 5500w) he should be stripping right around 3.37 gph (12.75l)

That’s about 56 ml/min. At 20% power, the pump I’m using puts out about 180. My hope is that I can beat those numbers with heat recovery, increasing the performance. But that tells me that I’ve got the right size pump for the system, with enough extra capacity to handle any reasonable variations.

[Steve Broady]

Also no need for cooling water, since the incoming wash is going to be doing the job of condensing the vapor.

Cool project Steve .
Yes it cqn be done …… but oh my god it is a critical balance .

Yhat was my ultimate goal when I had a crack at it but , while it is doable , I would suggest adding an Auxillary PC to deal with the periods …. That will happen…. When it does not run right and un condensed vapour comes out the spout .

Oh it will .

We shall see. My hope is that my electrical service is a lot more stable that what I’ve seen you have to deal with, which will make this thing a lot more stable. And using the peristaltic pump will hopefully let me dial the system in pretty accurately.

There’s a lot of hope there. Not all pie in the sky, but I fully understand the potential for issues.

My plan right now is to build it as a very simple system. One variable, the pump speed. The only data I will monitor will be the effluent temperature and wash inlet temperature. If/when that proves to be insufficient, I have a LOT of room for fine tuning. I could add some form of power control to the element. I could add a PID to control either pump speed or heating power or both. I could add another condenser (probably air cooled just to avoid the need for water). I could add an arduino (I’ve got a few and have been waiting for an excuse to play with them) to control any number of things.

The point being that I feel confident that it will be workable, either as built or with reasonable modifications. But I am definitely paying attention to the folks who have tried this in the past.

[pipes+hose]

Are reboiling or going to boil clean water? I sort of assume reboil but figured I'd ask.

What size marbles?

"That’s about 56 ml/min." <-- 12.75 L/h is 212 ml/ min. Which is nicely above your pump's 180ml/min.

[Steve Broady]

Are reboiling or going to boil clean water? I sort of assume reboil but figured I'd ask.

I’ll start it on clean water, but after that I’ll be feeding it wash, so that will be reboiled a bit before the effluent flows out the bottom.

What size marbles?

Roughly 12mm. I’ve used them in a reflux column once and got passable results, and the problems that I had there I ascribe entirely to my own inexperience rather than the marbles themselves. They seemed to work well, and I have a feeling what’ll do well here also.

"That’s about 56 ml/min." <-- 12.75 L/h is 212 ml/ min. Which is nicely above your pump's 180ml/min.

Duh!! Sorry, you’re right. That’s what I get for doing math while two different people are trying to talk to me and I haven’t had my coffee yet. That 180 ml/min was measured at only 20% power setting, at full power, I measured 425 ml/min.

[tjsc5f]

I’ve got a 0.5 L/min pump with speed control, which I’ve tested as being able to deliver 425 ml/min at full speed. My guess is that I’ll be running a bit below that at full power.

Do you have a link to the pump and controller you're using?

[Steve Broady]

Do you have a link to the pump and controller you're using?

https://a.aliexpress.com/_msnBeTI

[Steve Broady]

I had a little time this evening, so I soldered up all the copper parts. Nothing stunning to show, but the job is a little closer to being done.

[drmiller100]

If you start with 10 percent the magic chart shows one boil/condense cycle gets you 50 percent product.

A goal would be to have less than 1 percent alcohol waste and is easily done with 36 inches of 12 mm marbles.

You can measure with a meat thermometer

[Steve Broady]

I finally got a few parts in, and enough time to play, so I started building. I started by finishing up the copper work for the effluent side of things.

A quick mockup of the bottom end, and some stainless valves and hose barbs got added next.

I’m building the still into a cheap Harbor Freight tool cart for a couple reasons. One is portability, another is that I couldn’t think of a better (meaning cheaper) way to support it without mounting it to a wall.

As a side benefit, the cart will make a convenient place to mount the pump and thermometers as well as store any tools or supplies I might want to keep with it.

I added the boiler so that I can start figuring out the best mounting method. This is where I am at the moment.

[Steve Broady]

[Steve Broady]

I 3D printed some mounts for everything, to hold it securely to the cart. PETG sit well suited to 100 C temperatures, diminished some cellulose-lignin composite round stock to create an air gap and to serve as an insulator.

[Salt Must Flow]

Oh those mounts are very slick

[Steve Broady]

Some progress has been made. I started by cooking up a simple power supply for the thermometers. They run on 12V DC, and the pump runs on 24V DC, so it was a pretty simple job to make a 7812 based supply on a prototype board.

It’s going into a case which I designed and printed, and I’m mounting the wall wart directly to the back.

The case contains the peristaltic pump, two thermometers, volt and amp meter, and a master power switch. And after a little bit of fiddling to fix my own mistakes, it all works.

Now I’m just waiting on the rest of the parts to be delivered. It’s getting close.

[Thumperbunny]

I thort dis was going to be about somethin different....

[Steve Broady]

I thort dis was going to be about somethin different....

Sorry if I disappointed you! I don’t know about you, but I’m 6’3” tall, so a 2” stripper would be way too short for me anyway.

[Steve Broady]

I managed to get a little plumbing done the other day.

Both drains (one for the the boiler, one for the heat exchanger) and ends plumbed to a garden hose adapter which I printed. I used clear vinyl tubing because
A. It’s cheap and easy to work with, and I can use it for other projects as well.
B. It’s clear which lets me see what’s in the drain.
C. I wanted to know if it would work with standard PEX fittings (it does).

I also used the same tubing for the effluent overflow tube. That will almost certainly have to be replaced, but see point A above as to why it’s there at least temporarily.

I also replaced the element. I ordered a 5.5kW element with a 1.5” triclamp flange, figuring that on 120V it would be about perfect at just under 1500W. As it turns out, I was seeing closer to 540W. Gotta read the fine print… it was indeed a 5.5kW element, but for 380V. So I got a 1.5” TC to 1” NPT adapter and a 120V RV water heater element, and spent less than I did on the original TC unit. Lesson learned.

A short test showed that the boiler holds pretty close to 1200 ml, and came up to a boil in 4.5 minutes. So heat up time on this thing is going to be drastically reduced compared to my keg boiler.

The drain works nicely as well.

[Thumperbunny]

I thort dis was going to be about somethin different....

Sorry if I disappointed you! I don’t know about you, but I’m 6’3” tall, so a 2” stripper would be way too short for me anyway.

Haha, cool dat !

[Steve Broady]

It works!!

And by that, I mean that it turns cold water in a pot into warm water dripping back into the same pot, and hot water into another pot.

Column assembled, prior to connecting the feed lines.

I got everything hooked up tonight and gave it a trial run on water. I am pleased to report that it seems to be pretty stable across a range of input rates, with the effluent temperature fluctuating by only about 0.5°C until the feed rate was high enough to hold the temperature lower.

It’s a little hard to see, I know, but at 30% of full speed (so, roughly 150ml/min <- edited once I got some sleep and realized I had the wrong units) it’s holding a fairly steady 99°C at the effluent and 91°C where the feed enters the top of the column.

I’ve got a few little details to work out. That effluent overflow line is only functional if you caress it just right so that there are no low spots to form a trap. I’ll replace it with something reinforced, at least. And I ran out of 1/4” silicone tubing, so I need to get more to actually be able to feed wash or beer into this thing. Then the real testing can begin.

As a side note, I was pleasantly surprised to find that a corny keg fits almost perfectly underneath the condenser outlet. There’s even room for a funnel, so I don’t need to bother with any kind of outlet spout if I don’t want to. I normally strip straight into a corny keg, so this worked out ideally for me.

[Bolverk]

Very nice!

Was that 150ml, your lowest speed? Were you able to run it fast enough to see your effluent drop below 99c?

[Alzahra888]

Nice clean work. And on a lesser note, can’t say I’ve used these before.

[Yummyrum]

Cool stuff Steve . Looking forward to seeing how it runs with a real beer feed . Hope it runs OK .Fingers Crossed fir not too many modifications …….. but thats the fun stuff

You’ve done a nice job of this . Love the bench frame you’ve strapped it to .

[Steve Broady]

You’ve done a nice job of this . Love the bench frame you’ve strapped it to .

Thanks, Yummyrum! That frame was a result of walking around Harbor Freight looking for inspiration. $40 for a steel cart with wheels was very inspiring. And I have to say, it’s been handy! Makes it easy to move around as needed, it’s a super handy place to put tools and whatnot, and it even contains the occasional minor drip and leak. If I was doing this again, I would definitely put it on something similar again as well.

[Steve Broady]

Was that 150ml, your lowest speed? Were you able to run it fast enough to see your effluent drop below 99c?

That’s the lowest speed that I was certain I’d knocked down all the steam. It almost felt like it would work at even lower flow rates, but I wasn’t sure there.

Once I hit 60%, so roughly 300ml/hour, I just started to see the effluent temperature drop. I considered pushing in past to test more, but I was starting to get some surging from the effluent pipe that was overflowing the top, and it was close to 2 AM with me possibly having to go to work in the morning, so I just called it good enough and shut down.

Edit: That’s ml/min, not hour! I blame lack of sleep and lack of coffee. I got off work super late and just couldn’t wait to play with this thing the moment the parts arrived.

[Steve Broady]

Nice clean work. And on a lesser note, can’t say I’ve used these before.

I went looking for 1/2” NPT to PEX adapters, and that’s what was available at the store that day. Since I wanted some form of union to make disassembly and modification easier, it killed two birds with one stone. There’s a conical rubber washer inside which seals against the end of the threaded pipe - basically the female half of a union. In fact, if I ever needed to put a union in a piece of PEX, that’s probably how I’d do it.

[Bolverk]

300ml/m = 4.755 gph thats more like it!
1350w at 4.755 gph = 283w g/h fucking hell thats great!

Congrats man! Those are the numbers I was hoping you'd hit!