sand

stoker · Post by **stoker** » Mon May 29, 2006 10:58 am

how about the use of sand as 'double boiler',
I've some +: cheap, will not evaporate as water will, it can hold weight (<->water)

- : will I get stable temperatures with the use of sand? (equilibrium) I would like to use wood as fuel.
and will it conduct enough the heat?

junkyard dawg · Post by **junkyard dawg** » Mon May 29, 2006 12:47 pm

I think that might work as a buffer to control temperature fluctuations of a wood fire. It'll take some practice Im sure...

my thoughts: water for a double boiler is cheap too...water in a well designed double boiler wont evaporate either...

Whats your idea?

Swag · Post by **Swag** » Mon May 29, 2006 2:28 pm

It would be interesting to see how it works. Are you thinking about a thick layer or a thin layer? I would imagine that sand would hold the heat pretty well.

nanosleep · Post by **nanosleep** » Mon May 29, 2006 2:33 pm

You could also use oil. It won't evaporate. There is a fire hazard if you get it too hot and it boils (smokes).

muckanic · Post by **muckanic** » Mon May 29, 2006 5:35 pm

I've also seen designs for home-made heating mantles made out of diacotemous (sp.?) earth, aka betonite. For that matter, any mud-brick suitable clay would probably do. Make up a slurry, form it around the boiler, and let dry.

An alternative to vegetable oil would be ethylene glycol, aka anti-freeze, although there may not be much difference from a safety perspective.

Post by **Tater** » Mon May 29, 2006 5:47 pm

in old days when stills were set in the furnace mud and stone was often used to make a barrier from direct contact from flames of wood fires.Furnace was flued so heat ran underneath barrier up sides and exhausts from a controled outlet at or near top.

hornedrhodent · Post by **hornedrhodent** » Tue May 30, 2006 1:32 am

Water has the advantage that it holds the max temp to 100degC so you cant burn anything. By the time your boiler gets to 100C there's no ethanol left anyway.
When using firewood, keeping the heat input low enough is a problem. Flooding the column and having vapour and hot 95% liquid pissing out the top of the still get a bit exciting.
An overheated water jacket can be cooled rapidly by adding cold water. I wouldn't like to try that with brick rock or sand.

Rocky_Creek · Post by **Rocky_Creek** » Tue May 30, 2006 6:03 am

Water has the advantage that it holds the max temp to 100degC so you cant burn anything. By the time your boiler gets to 100C there's no ethanol left anyway.

Nice theory, wrong, but nice.

Post by **theholymackerel** » Tue May 30, 2006 6:52 am

???

Water requires either pressure or salts added to have the boilin' temp rise above 100C.

Please explaine Rocky Creek, I don't understand what yer sayin' at all.

stoker · Post by **stoker** » Tue May 30, 2006 9:07 am

I think I'll try it some day
an other advantage: less loose of energy (evaporating water takes a lot of energy)

Water has the advantage that it holds the max temp to 100degC so you cant burn anything. By the time your boiler gets to 100C there's no ethanol left anyway.

I don't think you will burn something with the use of sand. is you use a nice buffer (thick enough), then the inside of the sand will have the same themperature of the (boiling) wash, so, no possibility to burn something

possum · Post by **possum** » Tue May 30, 2006 11:47 am

One of my first "paycheck" jobs was as a cook for a big chain steakhouse.
They had breads and salads and soups on a buffet bar, in adition to the entree's and sides that people ordered. I started out in the prep kitchen, and the double boilers that they used were 7-8 gallon pots, with a stainless steel insert liner. The soup sits in the liner(this is great for cream soups, as it is unlikley that the cream will break dowm as fast), and the water sits in the big pot. OK, what is so different ? The liner had an mouth that was as big as the outer pot, and the weight kept the soup liner flush against the rim of the outer pot. The water that did boil, transfers its energy to the side of the soup liner, and then recondenses. These rigs would ocasionally burp a little steam, but only if they were running on too high a flame, and the soup was also boiling or really just too hot in the case of very thick stuff.

So what I'm saying is that if your doubble boiler is designed nicely, the boil dry problem is minimal. With that said, My rig does not have a well engineered waterbath, and the escaping steam has wasted countless hours of my time.
It is important that the water vapor does have a way out, so that nothing explodes.

hornedrhodent · Post by **hornedrhodent** » Tue May 30, 2006 1:58 pm

The water boiling dry in the water jacket is easily solved by using a small header tank which feeds water to the bottom of the jacket. The header tank is kept full by running the used cooling water into it.

By raising or lowering the tank you can control the level of water in the jacket.

hornedrhodent · Post by **hornedrhodent** » Tue May 30, 2006 2:21 pm

stoker wrote:how about the use of sand as 'double boiler',
I've some +: cheap, will not evaporate as water will, it can hold weight (<->water)

- : will I get stable temperatures with the use of sand? (equilibrium) I would like to use wood as fuel.
and will it conduct enough the heat?

The problem I see with sand is that it will just slow down the heat input but not control the temperature - water controls the upper limit for temperature without slowing heat input that much.

The problem with firewood is the variability of heat input and overheating. Either water or sand will give thermal mass to slow down the variation, but overshooting is the problem. It is easier to measure the temp of water than sand and easier to cool it down in an emergency.

What sort of still are we talking about?
SIAS - It shouldn't be too hard to test.

stoker · Post by **stoker** » Wed May 31, 2006 4:15 am

I would try it with my modified ministill
the mash in the boiler makes stabilase the temperature at a certain heat, not the water (sand). they will eventually all have the same temp

LeftLaneCruiser · Post by **LeftLaneCruiser** » Fri Jun 02, 2006 5:49 pm

Guys,
lots of discussion on this topic. And luckily most of it makes good sense

But my vote goes to oil in the double boiler. Vegetable oil (like for deep frying) boils at 180 degrees. As far as i know there is no way a mash gets that hot. So, before the oil even gets to smoke the mash should be completely boiled dry.

I think it is no coincedence that farmers in Germany, Austria and the rest of eastern Europe (and maybe other parts of the world) use double walled stills on oil for their (semi-) professional eaux-de-vie / schnapps / spirits.

KJH

junkyard dawg · Post by **junkyard dawg** » Fri Jun 02, 2006 10:41 pm

Thats a great idea. I'm planning on a major upgrade in my double boiler system and may design it for using oil. In my thinking, stripping runs could be done faster.

Any links to stills like that?

stoker · Post by **stoker** » Sat Jun 03, 2006 12:01 am

an other idea, would metal gauze inside the sand be a good idea?, so the heat is transfered fast enough to the ends of the boiler.
hot oil still evaporates and smells

possum · Post by **possum** » Sat Jun 03, 2006 8:03 am

A hot oil heat bath for a still makes me nervous. Ever get a drop of water in hot fry oil ? I have multiple scars fromm hot oil. Don't make the situation too dangerous. Hot oil boiling on an open flame with a combo of water and ethanol boiling on top of it would be a bit risky.

I don't want to hear about any of you guys on the news: "Moonshiner invents one stroke desil motor". I would use somthing non-flamable if I could.

stoker · Post by **stoker** » Sat Jun 03, 2006 10:28 am

LeftLaneCruiser · Post by **LeftLaneCruiser** » Wed Jun 07, 2006 12:23 am

Possum, don't get me wrong: it isn't an open oil bath in wich my still sits. For goodness sake.. I wouldn't even dare to step near the thing.

The boiler i use was already a double walled vessel when i got it, used for insulating food or something. I drilled a hole in the outer shell to fill and empty with water / oil / sand / other heat transferring material, and have a cork in the hole to seal it. The seal is not too tight, so if any pressure is building up it can blow off.

At first i used water, but i found that was boiling off quite fast and had to be refilled often. Second; it corrodes the outer wall wich is not stainless steel, but zinc plated iron.

KJH

pothead · Post by **pothead** » Fri Jun 16, 2006 4:35 am

I tried sand before. one of my first rigs was a stainless fire extinguisher that had a round bottom. I put it in a vessel of sand and tried heating it. I couldn't get it hot enough & it stunk badly.

Peanut oil can withstand high temps for long periods without burning. many other oils stink when burnt, and burn easily.

DixieBanjo · Post by **DixieBanjo** » Fri Jun 16, 2006 5:26 pm

I dont know how big your still is,but if its something like a milk can,you could get a big cast iron skillet to lay between the still and the flames.Ive done that before and the cast iron is great at holding heat.Or if its to big for a 14 inch skillet,get a sheet of steel.Ive never tried a vegetable oil double boiler,and it does sound like a good idea....but it scares the heck out of me.Picture this: A nice big,hot pot of glistening oil heating up a still down in some overgrown laurel thicket.Everything is going well...that sweet familiar smell is rising up from the still,and the moonshiner tending to it is sitting all cozy right up next to it doing what he likes to do best.......and then it starts to rain......

stoker · Post by **stoker** » Sat Jun 17, 2006 12:30 am

there's no way I'll use oil
my boiler is larger then a milk can
I thought about the iron gauze too, stuck in the sand, it would conduct the heat well

fahdoul · Post by **fahdoul** » Tue Jun 20, 2006 3:28 pm

Oil combusts if you get distracted and let it overheat. Water just evaporates and the boiler gets discolored or warped. You don't neeed more than 100C heat, so why not use water.

Re sand what you want is something which is a good conductor of heat that also tranfers the heat to the whole area of the boiler bottom so there are not hot spots like when you put a boiler on a electric stove burner. The ideal would be a 2" thick copper or alu boiler intergral with the bottom with and element embedded in it. Next best is a thick copper or alu layer integral with the boiler with an element under it.

A separate 2 inch copper or alu plate between the burner and the boiler won't work nearly as well since it will not conform perfectly, and there will be air spaces between the two surfaces and smaller areas of contact where most of the heat tranfer will take place.

Sand is not a good conductor of heat (to say nothing of airspace between grains), and will conform pretty well but not great to the boiler bottom. Odds are it will seem to work well until you notice how much longer your runs are taking - because the price you are paying is for more even heat is wasting most of it.

possum · Post by **possum** » Tue Jun 20, 2006 3:58 pm

Supposedly Helium is a good conducter. Of course it is notorious for escaping through the smallest of holes.

If you are talking about your copper water heater stoker, then I guess a metal plate wouldnt help.
But if you had a flat bottomed still, then the metal plate could be good.

stoker · Post by **stoker** » Thu Jun 22, 2006 3:21 am

yeah, it's for the copper boiler

pff, one exam to go, then I'll pick the hobby up again

AllanD · Post by **AllanD** » Sun Aug 06, 2006 4:00 pm

In a hot wood fire sand could concievably fuse together into a big lump of glasslike.... making a horrific mess on the "outer" pot.... if you had quartz/silica sand.

If OTOH it is "play sand", which could also be ground up coral
or seashells.....UN-fun way to inadvertantly make quicklime...
(is there a fun way to inadvertantly make quicklime?)

If you really want to try a dry media? Might I suggest shopping for some "Black Beauty"? (both a brand name and a coloquial name) Black beauty is Silicon Carbide made specifically for abrasive blasting.
It also is a better conductor of heat than any of the other types of "sand"
and if you manage to melt any I don't want to be anywhere near you when you do....

silicon carbide is most commonly used for making abrasive stones
Silicon Carbide has also been fused into rods for use as heating elements
Particularly in hydrogen atmosphere furnaces used in the aluminum industry... I doubt there is anything you could do to hurt it...

But it might be a viable alternative for a dry, non-reactive media for a double boiler.

AllanD

Home Distiller

sand

sand

Has this been covered? Waterbaths.

Re: sand