Anyone on here use the dry washing method and demeth the bd first? Im in the process of switching from water washing to dry wash and need to build a setup to safely demeth the bd. Im slightly nervous about building my own and having an accidental explosion, so I'm looking for some tried and tested designs.

 

Good to see someone "new" posting. I used a "GL EcoProcessor" design (basically a modified Appleseed design). It does work good for recovering Methanol. I need to build a more efficient condenser this summer. I've made about 1200 gallons so far and have managed not to blow myself up yet...

 

Ive checked out the GL EcoProcessor design before. I just need to figure out how to heat the bd up enough. Sounds like 120V water heater elements do the trick as long as you dont expose them to air or stop circulating.

 

That is the big explosion hazard, exposed elements in a methanol atmosphere. Always make sure the elements are submerged. As far as heating it up, the "tit" on the thermostat only alows for heating to 140 if I remember right. By removing it, you can turn the thermostat higher. I run ours around 180-185 with the venturi open. Once you get past about 175, it really starts to boil off fast. Ours is wired 220, which helps it heat up faster too.

 

Would biodiesel sitting around an element, or not being circulated, be a cause for explosion? That would be my only concern. Obviously I can wire it up so they run together, but I'm just looking at worst case scenario.

 

You would think only if air bubbles were present on the element? Need Fabman or one of the Bio Gurus to chime in on this one I think. We do keep several Fire Extinguishers on hand just in case, and I hang around while running the heating element...

 

We insulated a 250 gallon galvanized aluminum (or something rather) tank and welding two heating elements in the bottom. Thats being used as our oil heater now, might just re-plumb the setup so it can be used for both. Or even try to do "whole batch demething" while everything is in there.

 

I think that was Fabman's idea too, welding the element to the bottom of the tank, eliminating the direct contact with the bio. As far as whole batch demething, will that have some reverse reaction?
I drain off the Glycerol, then distill the methanol off the bio. The Glycerol is then used to pretreat the next batch of oil, lowering the titration and the ammount of methanol needed for the next batch.

 

I read about it on another forum. Supposedly they claim it's ok to do, I just don't know if it's really worth it anyways. Just something to think about I guess.

 

Welcome to the bio forum! I DO NOT recommend using submerged heating elements PERIOD!


I changed my process years ago to "stove top" elements UNDER the heating tank. I use a flat bottom tank with stove top elements bolted to the bottom of the tank, and insulated to the bottom. 0 chance of fire or explosion.

I use the same system for Methanol recovery. Much safer, and if an element burns out I don't have to remove the contents from the tank to change the element!

I'm in the process of building a whole new processor and will post pics when it's finished, but it may be a while because I'm still finishing up my new shop. I don't need to make any bio in the winter because I stockpiled bio from last summer.

What convinced me was a test I did with a 10 gallon glass container. When I saw bubbles forming around the red hot element I decided that maybe this wasn't such a good idea.......

 

Hi Don, glad you joined in. Hope all is well. What do think about a partial reverse reaction with a whole batch demething?

 

Morning Trent. I've heard bad things about whole batch demething, but haven't tried it. Why ask for problems...........

All is great here, just trying to finish our new house and shop. I'm putting in more hours/day since I retired than when I was working for a living.............lol

 

I think your not alone there, my Father-in-law says the same thing!

 

Yep, but at least I can pick the things I want to do!

 

I like your "stove top" method better. I just don't like the idea of a red hot element surrounded by fuel. Is you method as simple as it sounds? Just a couple round stove top elements attached to the bottom of the tank and insulated to prevent heat loss?