Wood Boiler stills

Simple pot still distillation and construction with or without a thumper.

Moderator: Site Moderator

Post Reply
myles
retired
Posts: 2451
Joined: Wed Oct 15, 2008 11:34 am
Location: UK, in the heather

Wood Boiler stills

Post by myles »

Hello folks,

Just out of curiosity, is anyone currently using a wood boiler on their pot still? Or are there any links to this subject that you know of. Thanks.
RumBull
Bootlegger
Posts: 123
Joined: Thu Mar 20, 2008 7:16 am
Location: Ozarks

Re: Wood Boiler stills

Post by RumBull »

Myles,
Have you been seduced by the photos of Pusser's wooden stills as I have? I think it is a cool idea and I have been tossing around some design. The way I see it, you have to be prepared to run it weekly in order to keep the wood tight and sanitary. I don't need another still but can't help myself, the wheels have been turning in my head for some time now.
7.5 gal and 15.5 gal SS keg with copper Super Sankey Scotch Style Still head.http://homedistiller.org/forum/viewtopi ... =16&t=8550
I make Rum and um... Rum
myles
retired
Posts: 2451
Joined: Wed Oct 15, 2008 11:34 am
Location: UK, in the heather

Re: Wood Boiler stills

Post by myles »

Yeh RumBull,
Pusser's is what got me thinking about it. You could keep the wood tight just by leaving it full off water when not in use. Same as a barrel.

The way I see it you would need to heat it with a copper coil in the wash. Either hot air or steam inside the coil. Steam means building a recirculating boiler with expansion reservoirs etc unless you just happen to have a spare steam boiler lying around!!!

Not sure how much control of the temperature you would have with that sort of setup. OK for full blast stripping runs but would want to back it off a bit on a spirit run. I supose you could add a valve and diverter to control the steam flow rate into the coil. Certainly is possible.
pHneutral
Novice
Posts: 94
Joined: Thu Jan 15, 2009 11:53 am

Re: Wood Boiler stills

Post by pHneutral »

Couldn't you adapt a small diesel steam furnace, or one of those wood burning, steam heater units designed for houses (a bit pricey though) for this? You'd have to have the heater positioned below the barrel so you wouldn't have to deal with actually pumping the steam, but...it might be a way around a lot of construction, and you'd only have to customize the heating element, and get the thermocouple setup in the barrel, or wherever you wanted it.
OldManP
Swill Maker
Posts: 175
Joined: Thu Dec 14, 2006 9:27 am

Re: Wood Boiler stills

Post by OldManP »

Wow...thought I was the only one dreaming of this. I'm more interested in it to decrease the cost of heating the still. I figured wood would be cheaper.

At first I thought of using it strictly for heat up, then switch heat sources (don't shun! i have some sneaky tricks on how to accomplish this). Figured if i get it up to temp then that would reduce the gas/electric bill.

Next I was considering using wood to heat up from the initial temp as above, but then do the same as mentioned earlier by using the wood to heat up a steam boiler so that steam or hot (near boiling or superheated water) would flow through the keg. There would be two closed areas in the setup to separate the heat up fire and the fire that boils the water for the steam coil. I was thinking the temperature of the liquid inside the steam coil could be controlled by a device that mimics a damper on a wood burning stove but instead of allowing different amount of air into the heater, it would direct/redirect the heat of the fire to and from the boiler area.

perhaps i'll try to include some drawings soon...no promises as i have not had access to autocad in the last few years.
Eagles may soar, but weasels don't get sucked into jet engines.
Dnderhead
Angel's Share
Angel's Share
Posts: 13666
Joined: Sun Dec 23, 2007 8:07 pm
Location: up north

Re: Wood Boiler stills

Post by Dnderhead »

Don't thank to complicated, hot water at a boils is 212F (100C) and it stays pretty constant. wood direct heating is not that hard either
but either one needs constant attendance. many nights have been spent listening to the sounds of the wild and the crackle of the fire,
you git used to those long 10-12 hour runs, and you git to know what to listen for, much like a mother and a baby. each and every sound
means something. first thing you know its braking day light .

by the way ,,,never done it before and won't do it again
User avatar
Tater
Admin
Posts: 9677
Joined: Mon Oct 25, 2004 9:19 am
Location: occupied south

Re: Wood Boiler stills

Post by Tater »

Seen steel barrels used to make steam boilers with.Was done around here a lot in old days. They would take a steel barrel and cut out center and weld in a 6 or 8 in pice of pipe letting it stick up a foot or so from top for a flue
weld half a barrel to bottom for fire box .make a hole facing away from everyone about size of your finger and tap tapered pice of wood into it for a safty blow plug Run a pipe over to still or mash box to distill or cook mash . Saw a setup like that in operation when I was a kid the still puker and thumper were all wooden barrels .They was makin apple brandy.
I use a pot still.Sometimes with a thumper
User avatar
Tater
Admin
Posts: 9677
Joined: Mon Oct 25, 2004 9:19 am
Location: occupied south

Re: Wood Boiler stills

Post by Tater »

Another way they would do it was like my grand pa preferred.Was to dig out a bank near a creek taking rocks and mud to build a rock furnace .Way he said he did his was to make a rock and mud flue that that laying barrel longways would be slightly longer then barrel. furnace was built in such a way as heat went leanth of the barrel came up behind it and then ran to front of the barrel to flue out the top with a mud and rock flue.kinda like a backwards S He also used a wood plug for a safty plug. he said that making the type with welded pipe flue was to much work .Dad always said that was cause him and his brother had to dig out the bank collect the rocks and build the flue. :)
I use a pot still.Sometimes with a thumper
myles
retired
Posts: 2451
Joined: Wed Oct 15, 2008 11:34 am
Location: UK, in the heather

Re: Wood Boiler stills

Post by myles »

This is getting more and more interesting. I am seriously thinking about putting in a sauna with a wood fired boiler to provide either steam or hot water running through copper pipes to provide the heat.

That same hot water or steam could feed the still boiler. Thinking a bit of camouflage here with a few false walls, cupboards, log store, etc could work to make the whole thing just look like a wood fired sauna with no still visible.
pHneutral
Novice
Posts: 94
Joined: Thu Jan 15, 2009 11:53 am

Re: Wood Boiler stills

Post by pHneutral »

If you run a wood stove boiling water directly, the steam will be at 100C. If you run a coil through a fire, the steam might get hotter than that. FYI.

I think the cheapest way would be to just put together a couple of steel drums, the bottom one to contain the fire, the top for the water, and regular pipe up to the still boiler, then a copper coil through it, led downwards, and then led through a worm or a truck radiator, to a holding tank that had a level siphon or float valve with your boiler. You could even design the whole thing to nest inside each other, to save transport space. If you wanted to be real efficient, you'd make a real rocket stove as the bottom chamber:

http://photos1.blogger.com/hello/175/78 ... 0stove.jpg" onclick="window.open(this.href);return false;" rel="nofollow

These are nice, since you get the wood to burn twice.. once as gas, once as charcoal.

Just some thoughts :) I'm sure some grandpappy has done all of this before..
OldManP
Swill Maker
Posts: 175
Joined: Thu Dec 14, 2006 9:27 am

Re: Wood Boiler stills

Post by OldManP »

Been doing a lot of research on rocket stoves. I think with some practice i can turn and old vertical cylinder smoker into a rocket stove. I will put it on full blast for the heat up, but then I was thinking to control the heat, adjust the wood/air flow as well as the skirt around the keg to control the heat into the wash. Just figure if i pull down the skirt there will be less heat transfer to the keg and allow a lower temp for longer, slower runs....probably just keep the heat up for stripping runs.

Any comments on this idea? Hopefully i'll figure this out soon. Wife says i gotta get the garage clean before any other projects...wish me luck!

OMP
Eagles may soar, but weasels don't get sucked into jet engines.
Hack
retired
Posts: 904
Joined: Wed Feb 06, 2008 7:45 pm

Re: Wood Boiler stills

Post by Hack »

I've been considering making something along the lines of a rocket stove for my setup, but rather than run wood continue to use my propane burner. I'm thinking it would give the same efficiency boost. I'm basicly considering an insulated tube that will fit over my keg boiler from the top down to just below the level of the burner. The propane burner gives much quicker control of the heat.
OldManP
Swill Maker
Posts: 175
Joined: Thu Dec 14, 2006 9:27 am

Re: Wood Boiler stills

Post by OldManP »

i understand keeping the heat restricted to the area around the boiler and I think it will be more efficient than and open flame.

I am going to try to use wood for cost though. Even if it's just through warm up, or during a stripping run. After a few stripping runs, then I should have a good idea on how the stove behaves, so i can maybe able control it on a spirit run. We'll see. Figure i can reduce the use of my propane burner for an hour or 2 while it heats up, that's all the more propane for the grill and for spirit run!

OMP

Plus, wood (in my area) is right out my back door...propane requires someone else other than myself and a chainsaw.
Eagles may soar, but weasels don't get sucked into jet engines.
Dnderhead
Angel's Share
Angel's Share
Posts: 13666
Joined: Sun Dec 23, 2007 8:07 pm
Location: up north

Re: Wood Boiler stills

Post by Dnderhead »

What if you had multibul coils ,,as two for heat up/stripping,,one for spirits run? you could keep water boiling (212F) and regulate how many
coils instead of water temps.
OldManP
Swill Maker
Posts: 175
Joined: Thu Dec 14, 2006 9:27 am

Re: Wood Boiler stills

Post by OldManP »

true....that was one of the next, more refined improvements, this would allow a fire not under the boiler but to act like a double boiler or a "steam" heating source.
Eagles may soar, but weasels don't get sucked into jet engines.
myles
retired
Posts: 2451
Joined: Wed Oct 15, 2008 11:34 am
Location: UK, in the heather

Re: Wood Boiler stills

Post by myles »

Well I think when I have finished my current build and move on to a bigger one, that I will go down the route of a solid fuel boiler heating water.

That will flow through an internal coil in the still boiler and probably an external coil also with the whole boiler insulated. Bearing in mind the problems that multiple internal coils will introduce, I think I will go down the slightly easier route and fit some valves instead to control the flow rate in the coils.

I imagine that I would run both internal and external coils during warm up, then shut off the internal coil completely and regulate with the external coil for the run to minimise the risk of burning grain or fruit in the wash.

My current double boiler is completely encapsulated with foam insulation and keeps ALL the heat inside the inner pot and I would use the same principle of (excessive??) insulation on the next build.
Hack
retired
Posts: 904
Joined: Wed Feb 06, 2008 7:45 pm

Re: Wood Boiler stills

Post by Hack »

myles wrote:My current double boiler is completely encapsulated with foam insulation and keeps ALL the heat inside the inner pot and I would use the same principle of (excessive??) insulation on the next build.
Not excessive, efficient.
Ugly

Re: Wood Boiler stills

Post by Ugly »

Going to jump in on this, I've been playing around with it and had some success.

Wood is cheap, I take it a step further and use charcoal... less hassle when I'm trying to distill and easier to start and work with. But wood will work fine.I should point out in advance I've only used a reflux still for purifying methanol and I've only ever used an indoor "on the stove" pot still to make hootch so I don't exactly know what all the requirements are for the different applications.

So you found out the BTU transfer per foot of copper pipe you're using, figured out how many BTU's of heat you need to raise the temperature in your specific pot size to the desired temp and sized your exchange coil then got it installed inside your still. Now you need hot water. Boiling water basically. It could be as easy as a big drum of water boiling away on it's side in a firepit. It could be a watertube arrangement inside a drum stove. A diswasher (commerical style) all metal pump attached to a variable motor controller lets you pump the boiling water through your internal coil. When you start reaching your working temp in the still, you can cut back your heat exchange by changing the velocity of the hot water moving through the coil via the motor controller or if you have no motor controller you can artifically restrict the water flow with a valve (that could be hard on the pump and I haven't tried it personally). Or you can just turn it off if you get too hot.

I initially fiddled around with a mixing valve capable of dumping cold water into my coil to control temp but it wasn't needed and killed my boil too fast, velocity control worked fine and by adding small amounts of water at a time I was able to maintain boiling without overcooling and killing my boil. I'm sure a steady trickle to replace the steam loss would be best...

This whole thing takes a while though, the more water you set to boil, the longer it takes. I settled on 20 Imperial gallons in my case and when it got boiling it took another good while to get my still going. But it did work and the fuel was free, no electric, no gas and it gave me an excuse to use some of the charcoal I had made to get the damn methanol in the first place. The cost of running the low amp diswasher pump is nothing in comparison.

I ran it twice, both with methanol. I wrapped a hot water heater insulation jacket around my still the second time with better results. Methanol run was simple and I was drying it out with zeolite the same day. I only run it outside when the weather is good and will have to take some snaps in the spring.

I understand that my flat out methanol runs are nothing like a whiskey run, but I suppose the fundamentals for exchanging heat are the same in either case. This is basically a big double boiler just like you use to make pudding in the kitchen without burning it.

I like it because it keeps my still away from open flame and I can still use wood/charcoal. I also thought of gassifying the charcoal in an Imbert gassifier (same concept as a turbo stove - wood gassification) and sucking the gas off to a low pressure methane burner for heat... but I'm too lazy and since this worked, I'm not even going to try.

The setup could be made better and hotter I imagine by using a pressurized system to get the water to hold more heat, but I'm leary of steam pressure and didn't want to risk it.

Regards,
Ugly
myles
retired
Posts: 2451
Joined: Wed Oct 15, 2008 11:34 am
Location: UK, in the heather

Re: Wood Boiler stills

Post by myles »

Thanks Ugly, good plan with the variable speed pump - that sounds just fine. Nice to hear from someone that heats with boiling water. The basic principles in powering a fuel or hooch still are the same.

I have planted a small patch of fast growing hybrid willow that I intend to coppice for fuel and will propagate more.

I have been playing around with the designs for a rocket stove to power the boiler. I am picturing a big heat exchanger coil or possibly a shell and tube type boiler built into the rocket stove flue. Separating the flame source from the still is one of my main objectives.

Not sure if I want to go down the route of generating superheated steam but with the rocket stove design it is a simple option. Keeping it simple with boiling water is a very attractive option.
Post Reply