In previous threads people have talked about reclaiming methanol from the leftover glycerine when making biodiesel.. how do you go about doing this? I've made about 100 gallons of fuel so far, I'd love to get my methanol back cause all I do right now is throw it away, it seems like such a waste.

 

One way is to put it back in your processor (make sure you have saved up enough to fully cover the heating element about a foot deep) then you heat it to around 170* or so and circulate it just like you do when processing a batch of oil into bio. If the glycerol is too thick to pump you can thin it with water. Reusing your wash water for this purpose will allow you to recover the methanol that came out in the wash too.

So, while it is circulating and heating you vent the vapors from the tank (from one of the top fittings) through a condenser. The condenser will cause the methanol vapor to condense back into liquid that you can then catch in a container. If you have a vacuum pump that you can put inline between the tank and the condenser and create a mild vacuum in the tank, that will cause the methanol to evaporate out of the mixture faster and more completely, and at a lower temperature too - so that you can recover even more of it.

You don't want to heat it too hot though because you want to minimize the amount of water that evaporates. Methanol boils at around 150* IIRC, whereas water boils and vaporizes at 212*. So around 160*-170* is just about right to evaporate the methanol but still leave the water behind. If you evaporate and condense too much water then it waters down your methanol - which can lead to a poor reaction when you go to re-use it.

You can do the same thing to recover methanol from your finished bio, but keep in mind that when you do, it will cause some soap to drop out. Most people do this BEFORE washing so that the soap that drops out of the bio can be more easily washed or filtered out. So the ideal way to do it is after draining off the glycerol, recover the meth from your bio. THEN wash and combine the soapy wash water with your glycerol to thin it, and then cook the meth out of that mixture.

Using their processor this way, I've read that some people recover as much as half of the total methanol that they used to start with. I'm getting close to being ready to start making my own bio, and this is the process I plan on using. The advantages I see to it (other than the obvious benefit of recovering around half the meth) is that you end up with the methanol free soap and glycerol mixed together, and have less water wasted in the washing process.

 

I built a small 5 gallon mini processor, but haven't had a chance to use it yet. maybe this weekend will get a chance to use it...

 

that sounds like more than my proccesor made of ten gallon rubbermaid containers and a turkey fryer can handle at this point.

 

I'm thinking the same about my 5 gallon pail... 175 might make the plastic rather soft?

 

5 gallon pail? You must be doing a lot of measuring. I use 1 gallon methanol to every 5 gallons oil. You can get clear plastic ten gallon containers at home depot for 6 buck each and they work perfect.

 

I only made the 5 gallon mini-processor for recovery of Methanol from the Glycerol, or if I wanted to make a small batch as a demonstration. The processor in my gallery is a 50 gallon water heater that we do 33-34 gallons of oil in...