WVO Glycerin Pretreatment

Another fantastic use for the glycerin byproduct sludge left over after making every batch of biodiesel!

Evidently, the glycerin layer byproduct (pre de-meth'd) can be used to pretreat the Waste Vegetable Oil prior to reacting. Put glycerin into WVO barrel, mix for a few minutes gently, let sit for 3+ days.

So basically, the glycerin from one batch of biodiesel (about 5 or so gallons in my case) can be added to a 55 gallon drum of WVO right from the settling tank (even if a 5% water pre-wash was performed) into my WVO holding tank. Big deal you may say...you could add 5 gallons of whatever you wanted to your oil, it is yours to do what you want with; but what does it do is the question....

By adding the glycerin to the WV0, you realize a few advantages.
The following things happen:

• water is absorbed and sinks to the bottom of the barrel (de-watering the WVO) eleviating the necessity to preheat the oil
• this may be due to the hydroscopic nature of the methanol left in the glycerin
  
• tallow, excess animal fats, and such come together and sink to the bottom
• a "winterizing" effect takes place, reducing the cloud point (where biodiesel starts to gell) of the final biodiesel product

Overall this process leaves a clearer feedstock that will produce a better quality biodiesel. Of course, this will also produce a layer of really nasty gunk on the bottom of your WVO barrel (which I have yet found a use for).

So the cycle begins again...




(this info has been obtained from http://biodiesel.infopop.cc/eve/forums/a/tpc/f/419605551/m/9441081511/p/1)