Higgins steam stripper / corn cooker

[Dancing4dan]

I keep noticing people going straight to the bottom with their steam. Is there a reason not using different levels to disperse the heat more evenly. I would think at the bottom then 40% up would do a better job...
Waiting to see how your new setup works. I'll soon be working on the steam side of my still.
Tōtō

It's a good question.

Steam would likely follow the path of least resistance requiring the steam outlets on the down tube to vary in diameter. Smaller at the top getting larger as it goes down. I'm not saying it wouldn't work. It would take some experimentation to get it balanced. The deeper the steam outlet is the more likely all of that steam will collapse and transfer its heat to the thumper contents. Look at how a milk frother works on a coffee machine.

The last steam run I did had product coming off the spout 30 minutes into the run and the thumper was at a full boil 60 minutes into the run. Initially I start at 100% power and decrease once the thumper starts to boil. 60% in this case. I find little difference in still output is achieved by increasing boiler power once a boil in the thumper has been achieved. There is a difference but not proportional to the energy input increase.

My steam down tube into the thumper is modular and can be set up with different heights to accommodate different thumpers. I use a 20 gallon pot, full size keg or a 1/2 keg depending on what I need. Personal experience shows that the closer to the bottom of the thumper the better it works. The thumper comes up to temperature faster. Once the thumper is up to temperature (boiling) the injected steam is not collapsing / condensing in the thumper as much and does does a pretty good job of stirring the mash as long as it isn't to thick.

[higgins]

I keep noticing people going straight to the bottom with their steam. Is there a reason not using different levels to disperse the heat more evenly. I would think at the bottom then 40% up would do a better job...
Waiting to see how your new setup works. I'll soon be working on the steam side of my still.
Tōtō

My previous downtube had a bunch of holes all the way down, covered with a SS braid. The bottom never got hot. So if this works OK I'm done. If not I can still add more holes.

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I like the copper locking pin. I'm going to brazenly steal that idea.
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No stealing involved ... freely given, though It's quite likely that I saw that idea somewhere else and it's not really mine to give.

[Tōtōchtin]

Higgins I hope that design works well for you. I'm going to be using deeper containers so I plan on having 2" coming in, I'll try heating from the bottom first. Pero I think a 220l will be too deep for that alone. I am going to try some 3/4" high temperature silicon tips that will be easily adjustable by cutting different size opening, I hope...
Tōtō

[shadylane]

I keep noticing people going straight to the bottom with their steam. Is there a reason not using different levels to disperse the heat more evenly. I would think at the bottom then 40% up would do a better job...

I inject steam at the bottom to keep steam bubbles from breaking the surface.

[ckdistills]

Thanks for the inspiration here! I've been thinking about a dual purpose steam stripper / thumper setup and it hadn't occurred to me to use my leftover 3/4 CSST.

The 3/4" valve is the main output to the keggle. It will be connected with a yellow CSST gas connector.

One question - it looks like you're using brass CSST fittings? Is that acceptable because it's being used for steam and not in the alcohol vapor path?

[higgins]

Yes, since it is only in the steam path I believe it is acceptable. If I ever use it as a thumper I'll build a copper connection.

[higgins]

I mashed up another bourbon back in late December and did the stripping on Jan 8 - one standard strip of the liquid, then one steam strip of the soupy mash. 36 lbs/79 kg mealed grain (25 lb corn, 8 lb rye, 3 lb malt), 20 gal/76 L water. I use the overnight cook method - boil water in evening, mix in corn & HTLAA, insulate overnight. Then in the morning I add the remaining grain and water and mash for a couple of hours. I cool with an immersion chiller, add GA, cool to 90F and pitch FSI 917 yeast.

I drained off 13.5 gal/51 L of liquid from the fermented mash, leaving 11 gal/41 L soupy mash. I reserved 3.5 gal/13 L for adding to the low wines for the spirit run charge, and stripped 10 gal/38 L normally.

I split the soupy mash into three 5 gal buckets, then during the regular stripping run I directed the output of the PC thru an immersion chiller in a bucket of mash to preheat it, moving between buckets to heat them all. Then when done stripping I pump the backset out of the boiler thru the chiller as well, and the 3 buckets of soupy mash were up to about 165F/74C when I was done with the first strip, so it didn't take long before it generated output. The steam stripping added about 3 gallons water to the mash, but I collected about 2.3 gallons in the process.

For the spirit run I combined:
2.4 gal/9 L @ 22% ABV from the 10 gal standard strip
2.3 gal @ 22% from the 11 gal steam strip (considerably more than I expected)
3.5 gal reserved wash
44 oz of bourbon feints @ 72%
for a boiler charge of 8.5 gal/32 L at 17.5% to run thru my flute.

So after 3 uses of the steam stripper I've seen my yield go up quite a bit over the squeezing method, and it is a fair bit easier to clean up afterward.

I'm sold on it.

I'm getting ready to strip a new bourbon batch - identical mash bill, but using YLAY instead. It will be interesting to compare the 2 batches when done.

[Dancing4dan]

Congratulations on your steam stripper!

Looking at your numbers you are using more boiler water than you should need to.

Are you insulating everything during a run? I find that insulating the boiler, steam arm and thumper makes a large difference on how much water the boiler uses / loses.

I suspect that steam is pushing any water that condenses in that line over to the thumper rather than allowing it to drain back to the boiler. The steam line needs to flow water in one direction and steam in the other. Water flow needs to be smooth and un disturbed.

Any area of level steam line and steam will move the water toward the thumper.

The steep incline of the steam line between the boiler and thumper will allow water to rapidly flow toward the boiler and cause a wave disturbance at the level steam line connection near the boiler. Steam will push this back up toward the thumper.

A steady and straight incline will allow any water to back flow smoothly and not be picked up or pushed over into the thumper by the steam.

[higgins]

Thanks D4D.

My steam boiler and stripping boiler are both insulated bottom and sides, but not on top. The steam line is also insulated, but is CSST, which probably makes for a turbulent steam flow out / condensed water return.

I stripped my last mash this week. It was 21Gal / 80L volume (18G / 68L water + 36lb / 16.3kg grain). I took off 12G / 45.4L liquid, leaving 9G / 34L mash 'slurry'.
I reserved 2G / 7.6L wash, then did a standard strip of 10G / 37.9L wash, getting 2.28G / 8.63L @ 23% ABV. I steamed the remaining 9G / 22.7L slurry and got 1.89G / 7.15L @ 27.4% ABV.

I started with 7.5G / 28.4L water in the steam boiler and there was over 4G / 15.1L left. As long as the element remains covered I'm not really concerned about how much it uses. HOWEVER, it is necessary for me to preheat the slurry with a wort chiller using PC output water, then hot backset. It was about 140F / 60C when I started the steam strip. Had I not preheated the slurry, it would have taken a lot more steam to run it, and my element would have become exposed.

I continue to be amazed at the amount of ETOH I get out of the slurry when I steam it.
Before I started steam stripping I'd normally get about 16G / 60.6L wash from that mash after draining and squeezing.
14G / 53L (after reserving 2G / 7.6L) would have yielded about 3.2G / 12.1L @ 23% (using same yield % as the first stripping run above).
With this batch I got 4.17G / 15.8L oz @ 25%.

[Steve Broady]

I continue to be amazed at the amount of ETOH I get out of the slurry when I steam it.

Have you noticed any difference in flavor or texture compared to your previous method? I’ve read plenty of comments about undesirable flavors coming from distilling on the grain, though I get that’s not quite the same as using steam.

[Dancing4dan]

The CSST will definitely lead to turbulence and more water used. Your steam strip would go faster if it wasn’t pushing water over.

I have used steam to distill an entire pot without draining off the liquid ferment in the past. I am now running the same as you. Drain and run the cleared beer. Steam the grains.

This way is the most efficient and imparts the least steam strip flavors to a batch.

[higgins]

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Have you noticed any difference in flavor or texture compared to your previous method?
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I can't say that I've specifically noticed something different in the white dog, but only age will tell. It is maybe a slight bit less flavorful, but I view it as an opportunity to learn the nuances about blending in bits and pieces of a few heads or tails jars.

My first 10 bourbons (which I recently merged into a solera type system) were standard strip/spirit runs on a 2" pot still. My last 4 have been using steam to strip AND also using my 4" flute with 2 or 3 plates. So any differences I might notice can't be directly attributed to either specific change. I guess I'd need to do a steam strip/spirit run on a pot still to see.

[higgins]

I LOVE my steam stripping rig

On Thursday I stripped an all-wheat YLAY fermentation for NGS gin base.

From a 26.5 gal/100.3 L mash I pulled 16.5 gal/62.5 L of beer from the mash, leaving 10 gal/37.9 L of wet mash.
First strip was 6.5 gal/24.6 L beer, using the PC hot water out & hot backset to preheat the 2nd batch to 140F/60C.
Second strip was 10 gal/37.9 L beer, using the PC hot water out & hot backset to preheat the wet mash to 150F/65.6C.
Last strip was steam stripping 10 gal/37.9 L wet mash.

I ran all strips down to about 4% ABV off the spout, or 25% ABV accumulated total.

I continue to be amazed that I get almost as much low wines (92.5% as much) from 10 gallons of wet mash as I do from 10 gallons of beer. I filled my steam gen keg with about 7.25 gal/27.4 L water, and after the strip there was 4.25 gal/16 L left, so no danger at all of exposing the element. I used ~3 gal water and collected ~2.3 gal low wines.

I want a good, clean neutral for a gin base, but would like it to be good enough for a vodka too. I'm going to run it thru my 4" 3 plate flute to get about 91% ABV to see how it goes. If it has too much flavor, I'll proof it down to 25% and re-run it thru my 2" x 44" packed column CCVM.

I still need to make a slight mod to my steam injector. Although it works very well as is, it is a pain to assemble.

I have to put the foot in thru the 4" port (offset from center) and hold it while attaching it to the down tube coming in the 2" port (center), and getting the holes aligned and the pin inserted is a real pain. So I'll add a 1/2" female adapter to the foot, and a 1/2" male adapter to the down tube so all I have to do is screw it on.

[Steve Broady]

I have not had good luck with threaded copper fittings. I found that they wanted to gall and seize. They’re fine for plumbing, but I didn’t like them for a joint I wanted to be able to take apart regularly.

If you find that’s the case, you might try a twist lock bayonet style mounting. Just solder a pin into the male end, and file an L shaped notch into the female coupling. Bonus points, it’ll be much easier to align by feel.

[Bolverk]

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Have you noticed any difference in flavor or texture compared to your previous method?
...

I can't say that I've specifically noticed something different in the white dog, but only age will tell. It is maybe a slight bit less flavorful, but I view it as an opportunity to learn the nuances about blending in bits and pieces of a few heads or tails jars.

I'm new to steam, so take this with a grain of salt... But I noticed when stripping on steam you have to be careful with the volume of steam you're putting in because it may not be fully condensing in the beer and you might have water vapor carrying over. That could be what is diluting the flavor a bit.

What I did was run the steam gen at 100% (4500w) until first drips. Then dial back the heat input until the output matches what your beer abv should collect at as a condensed vapor. This abv chart will help a lot.

So say you have an 8% beer, that should be coming off the still at around 50%. If you're getting it come off at say 30% you know you pushing your steam too hard.

[Born_Free]

The Injector assembly at the kettle is made from these parts:
Steam2Kettle_1.jpg

Higgins,

This saved me going down a silly path, love the idea to drill out the coupling. Thanks.

I to used a 3/4" copper pipe into the still. I was surprised how long it took before steam came out the end when doing an all water run during testing.

The steam was condensing in in the copper all the way until the water was boiling. I could feel the top of the still getting hot before the bottom. I wonder if people using 1/2" get a different result?

Here is what I ended up with:

[higgins]

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This saved me going down a silly path, love the idea to drill out the coupling. Thanks.
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Hey Born_Free. That looks great, and I'm sure it works as good as it looks.

[higgins]

After 4 or 5 times using this steam setup there were a few things I was not happy with, so I've made some modifications.

I would do 2 strips of cleared beer, then a 3rd strip of the slurry with steam. That meant I had to change the still head to add the Tee with the steam injector in it. That was a pita, so I decided to move the steam injector to the 4" offset port. That allowed me to keep the still head intact and just add the steam injector. Another reason to do this was that on the steam strip it seemed to go a bit more slowly, which I think was due to the 2" port being partially occupied by the steam injector tube. Removing that would allow more vapor out.

The CSST from the steam generator to the injector seemed to cause a lot of the steam to condense before it got to the kettle, even though it was well insulated. I removed the CSST and the flare fittings it was connecting to, and replaced it with 3/4" copper with copper elbows and unions. Easier to set up and more 'adjustable' where height is concerned.

The steam injector foot was a pain to put on/take off, and most times I used it some mash would make its way into the injector tube. So I took the advice given here and made a new foot using the black silicone nipples with slits in the round end. Changed the injector tube to add a threaded fitting, and use a 2" x 4" bell reducer to attach to the 4" port. Now I put the injector tube thru the 2" x 4" reducer, clamp it, then screw on the steamer foot and clamp the assembled injector into the 4" port.

It is now much easier to quickly switch from 240V stripping to steam stripping just by adding the injector thru the 4" port.

[BlackStrap]

Looks really good higgins...

I used stainless outer hose sheathing to solve the issue of anything plugging up my boiler while coming up to temps.

Mainstays-30-inch-Stainless-Steel-Faucet-Supply-Line-Hose