Hello,
I am new on this site. Im am running a Mitsibishi L300 4x4 on WVO for the last 5 years now. The minivan is equipped with e second heated tank for the WVO. We filter and settle used vegetable oil. Also for some friends. We also have just started making biodiesel from the settled fraction (the greasy part of the WVO). Yesterday we produced our first batch (around 500 liters of biodiesel). It gave also some 120 liters of byproduct: glycerine, methanol, KOH and probably a bit of soap.
The byproduct is a very thin looking mixture and extremely degreasing.
I am playing with the idea to purify the glycerine en than mix it with the WVO. This to prevent part of the settelment of the greasy part of the WVO. This way, we could use 100 % of the WVO.
Question of course is:
1. Will adding glycerine effective te prevent part of the settlement of grease in the WVO
2. Will added glycerine influence the combustion in the engine.

I tried to find the answer on this forum, but no succes (maybe I am not looking well enough.

Thanks,
Niek

There's a reason that Glycerin from Bio production is a waste disposal problem for private and commercial enterprises alike.
If it could be used as fuel, it would have been well and truly done by now.

quote:

Question of course is:
1. Will adding glycerine effective te prevent part of the settlement of grease in the WVO

It will actually cause more to drop out. Mixing glycerin with WVO is an effective way to remove the animal fats to make processing the WVO into biodiesel easier and of a higher gelling point for the finished BD.

quote:

2. Will added glycerine influence the combustion in the engine.

Almost definitely yes. Probably in a bad way. I bet there are some really old, all mechanical, indirect injection engines that could get by with a really low percentage glycerin mixing in...but I won't be risking any engines or any of my cash to try it.

quote:

If it could be used as fuel, it would have been well and truly done by now

there is a company that found a way to essentially ultra refine glycerine so it can be used as
a fuel in CI engines. i saved the link but cant find it now

Trying to run an engine on fuel which contains significant amounts of raw waste glycerol will almost certainly ruin it in a very short time - thats if it runs at all. If you go to the trouble and expense of purifying the glycerol to remove the soaps and salts its worth too much to be wasted as a fuel.

^agreed. Not worth the effort.
Glycerol pre-treatment of WVO however may be worth consideration to lower FFA's.

Over the last couple of years there has been development of some sort of fairly small catalytic cracking equipment that takes in raw glycerin, adds heat, and out comes hydrogen. The equipment is small enough to be located on a vehicle, they were doing a pilot test powering a diesel engine to produce something like 20KW of electricity. This is being developed by a professor and grad students at the Univ of Wisconsin at Madison, the development is being kept propritory and the last I read they had created a corporation and were partnered with one of the world wide oil companies.

Another option is to use the raw glycerin as feedtock for a bio-digester and produce low BTU natural gas (methane).