why is dewatering so important in the biodiesel process? there seems to be some water content in all the dino fuel so why all the emphasis?

 

dewatering is important in both. Its why we run water-block filters and water-in-fuel indicators. It can boil and impinge under pressure and rot metal parts.
I tried doing the heat and spray method but it left a lot of water behind. I found the best way to remove water was to heat the fuel to 180F in a water heater tank and draw a vacuum on it until it stopped bubbling.
I need to make a condenser of some kind the next time I do it, Im wrecking my vacuum pump with the steam.

 

Why not take the water vapors off the top of the still and run them thru a condensing coil and then a rag separator with the vacuum pump on a bypass?
Just sayn

 

Biodiesel can hold a lot more dissolved water than ULSD. And it doesn't shed the free water as well (more likely to make emulsions).