First the fine print. We're dealing with a flamable, explosive, neurotoxic liquid/gas here. Also note that if you try to drain the glycerin immediately after the distillation, it will be extremely dangerously hot. The information here is presented for educational purposes only. This setup worked well for me, but I take 27 multiple redundant steps to INSURE my safety which I am not showing or describing, since you can't possibly describe every possible thing that can go wrong, and what to do to prevent it.

If you decide to build a still, YOU are responsible for doing your research to make CERTAIN that you are doing this in a safe and responsible way, outside, with fire extinguishers of suitable size and type, etc etc etc.

OK, you've been warned.

For those who don't want to mess about with the expense and complexity of a vacuum pump, here's a straightforward atmospheric still. By the way, I haven't seen anybody show the math for how you save energy or money with vacuum distillation vs simple heat/atmospheric distillation. Sure, it takes lower temps with some vacuum, but you're also consuming energy to make your vacuum. There really is no such thing as a free lunch. Vac pumps usually aren't cheap either.

I'll describe it, then I'll post links to pic's of the components.

The condensor is a ten foot length of 1/2 inch soft copper tubing coiled up in a five gallon plastic bucket to hold the cold flowing tap water. The coil is secured at the top, the bottom, and once in the middle, which is the short copper tube soldered on at right angles. It's just a brace to the bucket.

I run a bubbler from an aquarium pump in the bucket because I was getting a lot of temperature stratification in the water. Quite hot on top, cool on the bottom. The condensor must slope smoothly downhill to the output, which should be the lowest point. No dips, no sags, etc. The condensed methanol must freely drain into the catch vessel just by gravity. I run a slow but steady stream of cold tapwater through the bucket, so there's an overflow for that. I like to keep the water in the bucket at 70F or less. My tapwater comes out around 50F prior to hitting the bucket.

Your condensor must be capable of removing just as much heat as you are putting into the still, pretty much. A single bucket of icewater won't be nearly enough cold to condense all the methanol from one batch.

The still itself is a converted 30 gallon water heater with an electric element (220 operated on 120 to preserve element life). I now run two 220V elements each rated at 4,500 watts. I had to weld in ports to do that. I couldn't find a big enough cheap 220V element that produced enough heat when operated on 120V. Since I operate them on 120V, that cuts the effective wattage to 1/4 of rated, or 1,100 watts each, a total of 2,200 watts (actual). I did a couple of runs with a single 220V element run at full voltage/wattage. It was plenty of heat to get the run done in a timely manner, but the element burned out on the second run. The pic of the still shows a bare tank, but I put a fiberglass water heater blanket over it when I run it. It's important that the boiler/pot/water heater be well insulated, or you waste energy and make the distillation go unneccesarily slowly.

I typically put 16-20 gallons of byproduct in for a batch. I welded a two inch port on the top to make it easy to dump glycerin in. And don't forget when you're done, the glycerin will become a solid at anything close to room temperture (if you used NaOH as your catalyst). So don't wait too long before you drain you meth-free glycerin out. I replaced the mickey mouse drain valve with a 3/4 inch ball valve to drain it efficiently. Don't burn yourself when you drain it.

I monitor the temperature of the output right where it comes out, and it runs around 140F while the bulk of the methanol comes out. As production goes along, the temperture climbs. I stop production when the output temp is about 180F. By this time, the rate of methanol production has dropped to a very low rate. This suggests that I have recovered the vast majority of the available methanol.

I used a piece of automotive heater hose to make the 180 degree turn from the output of the still to the 3 foot piece of straight copper that connects to the condensor.

Here's the first pic of the condensor:

This message has been edited. Last edited by: troy,

condenser_2_sh.jpg (43 Kb, 1621 downloads)

I can't seem to post more than one link, so we'll do it the hard way. Here's another pic of the condensor:

condenser_1_sh.jpg (46 Kb, 1298 downloads)

Here's a pic of the output spout of the condensor:

condenser_drain_sh.jpg (39 Kb, 1203 downloads)

Here's an overview of the whole setup, without the insulating blanket strapped on. I know it looks like a gas water heater, but I assure you it's been converted to electric:

ps, the overflow pipe wasn't big enough, as pictured, that's why you see a sypon hose in there as well.

tr

overall_sh.jpg (84 Kb, 1429 downloads)

Troy, I really like your setup. Any chance of you sending me pics via e-mail please (I'll PM you with my address)

I appreciate you detailing the still on here.

Ian

I would happily send pics by email if you wish. Were you unable to open the links to the pics???

Finest regards,

troy

troy,
Have you recovered methanol using the glycerin pre wash? Thats adding 5% water to the end reaction. I like your setup and have a 40 gal heater that i'm going to change out in the spring. Just wonder how much of the added water that is in the glycerin will come out in the methonal?

TL

Dear TL,

I don't do the glycerin pre-wash, so can't comment from actual experience. However, there is little reason to think that you will have any trouble if you keep the output temp at 180F or below, as measured right where the gas exits the pot. The boiling points are different enough to allow for very good separation with high purity. Also, methanol does not get married to water like ethanol does (the formation of an azeotropic mixture)so that makes it vastly easier with meth than eth.

Finest regards,

troy

Troy, the last batch I distilled I found that the last gallon or so of methanol that I reclaimed had water in it. Obviously I let the temp get too high and started to reclaim my water of the byproduct.

Could I just re-distill the last gallon, keep the temp below180-190 degrees F and collect the methanol and leave the water?

My condenser is virtually identical to yours. My still is barrel with a hot water heater element in it.

Thanks,

Wayne

With Methanol, this will work, but if you tried with ethanol, the azeotrope would limit with a water content of 5% or more.

Dear Wayne,

Yup, what Tony said. Keep the temp (at the output point) below 180-185F and your water problems should go away.

Finest regards,

troy

Troy, a question about your condenser tubing. I believe you say it is 1/2" tubing.

Mine is 1/2" also but that's the outside diameter. The inside diameter is only 3/8".

Is this the same as you have or is yours 1/2" inside diameter.

The reason I ask is by my still runs excrusiatingly slow and I wonder if maybe it's because my tubing is a little too small.

Thanks,

Wayne

It's sold as 1/2" inside diameter, nominal. More heat will make the still run faster, BUT that also mean you need a higher capacity condensor. Your condensor must be able to remove as much heat as you're putting into your pot. If the output of your condensor is hot, your condensor isn't efficient enough. Hot for me means anything over 70F.

More insulation on your pot will also make things run faster, making better use of the input heat. BUT, anything you do to make it run faster obligates you to have a bigger and/or more efficient condensor to keep up.

Home distillation of flammable toxic fluids and gasses is an inherently dangerous activity. Don't do this unless you have completely educated yourself and are totally confident in your equipment, your protocol and your safety precautions. If in doubt, have your friendly local fire marshall inspect your setup.

Good luck, have fun, play safe and take multiple redundant safety precautions.

troy

Thanks Troy. I have used this still before. As I said, it's virtually identical, other than my still is a drum, to yours. The condenser is identical although my tubing is 1/8" smaller in diameter.

I have insulated the hell out of the pot. I use a safety valve which is a pressure relief valve made up of a piece of clear hose going into a pitcher of water. If the water rises, there is pressure. To date the water has never risen. I also have a pressure gauge on the still that can be read at a glance in case I don't notice the water level rise.

The first time I ran it I used ice to cool the condenser. Now that we have snow on the ground I'll use snow. It's a hell of a lot cheaper than bags of ice!

I'm thinking of building a new condenser using an automotive radiator with a box fan behind it like I saw somewhere else on this forum.

What do you think about the car radiator thing?

Thanks for all your help, suggestions and pictures.

Wayne

I have no experience with radiator style condensors, so I can't really comment on their efficacy or efficiency.

Good luck and have fun!

troy

I have used a small older flat style radiator off of something about 12x12 square and cool with a fan and it works pretty good-using an older style self sealing pressure cooker to heat the glycerin on low heat. have been recovering about 30% of the methanol!

Hi Troy
just a quick question ... referring back to the opening post here ..I think you said some thing to the effect you have to get rid of as much heat as you put in ..
my thoughts on this is ..ok I raise the gly to 68 deg C to turn it to steam to evaporate off) ..may be a couple of degs higher to maintain the evaporating ... logic says to me that if glyc is liquid under 68 deg and vapour above then rather than having to remove all the heat I added to get up to vapour stage ,,the condensor only had to lower the temp back to below 68 deg to return it to a liquid state so inreality only having to remove a few degrees rather than the 30 odd it took to get it up to the vapour stage

As I said this is just logic and am not sure ..but welcome the infor from you folks that have more knowledge or experience in the field ..
Regards
Kev

makes sense to me, but I am just reading this info so far...

would think you only need to cool it to below the "dewpoint" of methanol. not all the way down.

Dear Kev,

Your logic is good, but it's more compex in real life. If you had PERFECT control of the temperature of the outgoing methanol vapor, you would only have to chill it below the condensation temp. But do you have perfect control? To prevent the escape of valuable (and toxic/flamable) methanol vapor, you'd be well advised to cool your condensor to a level well below the condensation temp of methanol. It's safer that way.

If we ignore the safety margin issue for a moment, we still have to deal with the in/out heat question.

If it takes 1000 BTU's of heat to vaporize x kilograms of liquid methanol, it will take pretty much 1000 BTU's of cooling (heat removal) to condense x kilograms of methanol vapor. There's just no such thing as a free lunch in physics. It never works out exactly in the real world due to inefficiencies, but that's the idea.

Finest regards,

troy

Troy, your bucket, you only put water in it? And it cools?

Or are you continualy adding cold water to it?

If so where to you drain the water from the bucket? bottom? Side near the top? It seems like the side near the top is where the water gets the hottest.

Thanks,

Wayne