I have built a new methanol recovery still which has 2 heat sources. First a 3000w immersion heater quickly brings the glycerol up to boiling point then a British army no 12 cooker, running on biodiesel, takes over and maintains the still at a gentle boil.
There are details of the No.12 cooker can be found at Biodiesel for Heating.
The capacity of the still is 40 litres and should yieild 8-10 litres of methanol in about 5-6 hours.
Im testing it this weekend and will post results and pictures.

The new still has worked very well. I put 40 litres in and the 3000 watt element heated it up to boiling in less than an hour.
I filled the no.12 cooker with 1 litre of biodiesel and lit it. The immersion heater was turned off and the cooker maintained the reflux head at 72-75 degreesC for 9 hours. I checked it every half hour and pumped up the pressure occasionally, otherwise it needed no adjustment. After 9 hours I have consumed just over a litre of bio and I have 8.5 litres of methanol at 90% purity. I could continue as the methanol is still dripping but its late and I have to work tomorrow.
So I am well pleased with my new still.

Sounds terrific! Some pics would be appreciated

Although the still worked perfectly I have a reservation about using the No.12 cooker for this purpose. After the 12 hour run I noticed that the valve on the cooker was not working well. I opened it up and the brass valve stem has broken. The damage seems to be the result of overheating so perhaps this type of burner is not designed to run for such long periods.