Geting rid of Methanol in a continuous plate

decoy · Post by **decoy** » Fri Jan 06, 2006 4:57 pm

there is a bit of talk related to striping of methanol and fusil oils by removing a portion of the the start and end of each batch...

if i build a continuous plate still how would you get rid of the methanol ?

The Chemist · Post by **The Chemist** » Fri Jan 06, 2006 5:23 pm

With a plate still, you pretty much just have to live with a little more methanol than in other designs. Is that a good thing for homedistillers? There are many reasons a homedistillers should stay away from a continuous still--in my opinion, this is one of them. In a commercial application, there are many controls, and the distillation is kept to a rock-solid equilibrium to minimize methanol content. Not really practical on a small scale. There are several resource, here and other websites, about the continuous design. Have a look at several, and decide if you really want the hassle.

rectifier · Post by **rectifier** » Fri Jan 06, 2006 11:41 pm

Lots of interest of late in continuous stills it seems!

I'm (probably) one of the only owners of a continuous still here - and I only use it for fuel experimentation. I have done quite a bit of research regarding them.

To put it simply:
If you are going to run a continuous still, you are going to have to rerun your product in a batch still if you want truly pure ethanol with no methanol or heads!

Doing that then wrecks the whole point of continuous operation, namely the easy, efficient processing, since you have to
a) have a whole other still, or screw your column in half and mount the top on another boiler
b) you have to run it again, and waste time and energy heating it up again

so unless you are interested in fuel, I would say don't waste your time.

To put it longer if you are thinking of building a true "fractionating column":
As I've told others, it is most likely too much of a pain in the ass for beverage alcohol due to the constant heads (methanol) problem. Chances are low that you will be able to design and properly equilibriate a column that can remove methanol and ethanol at different heights.

It's hard to maintain multiple, stable, equilibrium points in a homemade, packed column. That's why we usually only have one point, at the top, where it's easy to maintain via reflux. And if you want to play with plates - well then, you are going to be spending a lot of time, and most likely money on this. Be warned that you will need a lot of plates or HETP between your methanol and ethanol takeoff, and that your methanol takeoff rate is going to be extremely low, causing equilibrium problems.
This would be the most advanced still to build, and there are no existing small scale plans that I know of with multiple takeoffs. Unless you are a physical chemistry wizard - go for the batch still.

The Chemist · Post by **The Chemist** » Sat Jan 07, 2006 2:17 am

Decoy--I see now that you're probably talking about the Bokabob angle plate still that you posted in another thread. This is not a continuous still, only a type of fractionating column, and you'll be fine (i.e. not have the "continuous heads" problem rectifier and I were talking about) just throwing out the first 50 ml or so.

linw · Post by **linw** » Sat Jan 07, 2006 3:42 pm

Sounds like damn good advice, Rectifier. The better mousetrap brigade probably won't listen, though!!

decoy · Post by **decoy** » Sat Jan 07, 2006 4:31 pm

i dont think i fit into the better mouse trap brigade, altho i feel some things can be realisticly simplified.

i have built a couple of pot stills and am happy with there operation.

my freind purchased a small fract still from NZ and showed me the homedistiller www, i guess i was in need of a new project and was fascinated in making a larger column still...

i fit more into to the class of tinkerer....

the last couple of months have been a fascinating lerning curve for me and i havent looked back...

decoy · Post by **decoy** » Sat Jan 07, 2006 4:56 pm

The Chemist wrote:Decoy--I see now that you're probably talking about the Bokabob angle plate still that you posted in another thread. This is not a continuous still, only a type of fractionating column, and you'll be fine (i.e. not have the "continuous heads" problem rectifier and I were talking about) just throwing out the first 50 ml or so.

this is my first of step many to a larger plate still, i am not making the still to just produce alcohol, its the learning curve.

my next step will be a 4" plate still useing the pyrex glass of Primus gas mantle lanterns for the column with stainless plates so i can see whats going on inside.

And i just picked up a 2mtr length of 6" copper tube which will be might be my final pride and joy, from documentation i have read it should be able to produce approx 18 L/hr it will be intresting to find out if this is true..

and now i am keen on making one that seperates methanol seing that its boiling pont is some 15 deg C diferance.

The Chemist · Post by **The Chemist** » Mon Jan 09, 2006 8:25 am

decoy wrote:my next step will be a 4" plate still useing the pyrex glass of Primus gas mantle lanterns for the column with stainless plates so i can see whats going on inside.

That sounds like your just asking for trouble. What about the different expansion coefficients of Pyrex and SS?

decoy · Post by **decoy** » Mon Jan 09, 2006 4:30 pm

i will use food grade silicon gaskets between the stainless and glass wich will allow for a fair bit of movment..

pyrex is comonly used as a sight glass sandwiched between to stainless flanges

The Chemist · Post by **The Chemist** » Tue Jan 10, 2006 6:13 am

decoy wrote:i will use food grade silicon gaskets between the stainless and glass wich will allow for a fair bit of movment..

pyrex is comonly used as a sight glass sandwiched between to stainless flanges

Okey-dokey (hey, I'm a chemist, not an engineer!!). Are you after rum, vodka, or fuel?

decoy · Post by **decoy** » Tue Jan 10, 2006 4:29 pm

I am not making this to produce alcohol its just a hobby i like to build stuff i guess its more of a case so i can say i have built it, polish it up and have it as a showcase.., I already have a pot still made out of two old copper cloths boilers which can still be found here in Australia, i pick these up from scrap yards for around $20 each.

the copper boilers can be found as gas or electric already to go, you simply get a second one rip the guts out turn the coper pot upside down and make a gasket and a few clamps.. and your prety much good to go..

when i get a chance ill set it up and take some more pics and post on here as an idea for others...

I get a lot of plesure and relaxation out of building and making things.

to answer your question

1. make a scaled down plate still
2. high proof ethanol 95%+
3. continues process
4. strip Methanol and fusil oils
5. use minimal water

Rocky_Creek · Post by **Rocky_Creek** » Wed Jan 11, 2006 4:29 am

Get plenty of photos of your face. The plastic surgons will want something to work from.

decoy · Post by **decoy** » Wed Jan 11, 2006 4:04 pm

what is your problem Rocky Creek are you talking from experiance..

I thought this forum was to learn a hoby and try and help people, if you want to flame people go to one of those Univirst student/imature gamers forums like SGL or QGL, I did not think there would be people demonstrating imaturity on this forum, but i guess there is always a clown in evry group..