I'm in the process of thinking out and designing my processor. 55 gallon drum with a weld on cone bottom and a band lock lid. Harbor freight pump. A 4" thin wall steel pipe will pass through my processor. One end will vent to the outside and the other will be attached to a olsen fuel oil burner located in another room.

OK, what if I attached a condenser column to the top of my processors lid. After processing for 30 minutes at 130F with the pump still running I bump up the temp to 158F and distill of the methanol before settling out the glycerin.
Would this not also get the small amount methanol out of the biodiesel that is removed in the wash.

Anyone's thoughts on this would be welcome. Why wouldn't it work? It would use less energy heating from 130F to 158F It would get all the meth not used in the reaction.

you are going to run the risk of reversing the reaction for one if you dont seperate the glycerine. I guess it can break the methyl molecules back away from the bio, or something aong those lines. I only recover from the glycerine, as the 3-4 liters of ME from the bio is not worth the time to me. Id rather wash it out.
The other part I noticed is that you are only reacting for 30 minutes. I run my pump for a minimum of 2 hrs to react 47-50 gallons using a NT pump. It would take one heckuva pump to get complete conversion in 30 minutes. Run a 3/27 test before shutting down the reaction phase.

Tim,
What hooknline said about the back reaction is true. However if you neutralize the excess caustic first, and keep the temps down while demething it will mitigate the back reaction issue.
See This thread for a successful method of doing this called the GL push/pull.

quote:

A 4" thin wall steel pipe will pass through my processor. One end will vent to the outside and the other will be attached to a olsen fuel oil burner located in another room.

That should work very well to heat the oil rapidly. However this can also be very dangerous. I would not recommend a thin wall pipe for the heat exchanger. I see no advantage for thin wall only obvious disadvantages to safety. I would think the burner will be able to very rapidly heat the pipe well beyond the ignition temperature of the oil never mind the oil/methoxide mix or methanol fumes left in a drained reactor so be sure to put some quality temperature control along with highlimit controls and some redundancy to ensure you don't blow her sky high!
Jon

quote:

Originally posted by hooknline:
Run a 3/27 test before shutting down the reaction phase.

Do you run this test on a sample before you shut down the pump or after settling out the glycerin. Also considering a radiant heat circulator pump. Better flow than the NT pump and good to 220F
Thanks

Yes, before you shut down the pump take a sample in a jar and the glycerin will settle as it cools for the test. The glycerin will not effect the test.
Be cautious of the type of circ pump you choose, B&G series 100 for example is the pump I started out with but it was really not up to the task. It is designed to run in a closed loop system with no pressure and very little head. Taco, Grundfos, Wilo all make circ. pumps that seem to work better than the B&G circ. pumps...
Jon