Can you do a 5% pre wash immediately following removal of glycerin? I know this is not the normal method but why wouldn't this work? Main reason is keeping water out of glycerin for meth recovery.

I have no experience with the 5% pre wash but I would think that if the glycerin was not present for it you would end up with a GIANT emulsion after it goes through the mixing pump...
I also think it would just be called a "wash" as I believe the pre means pre glycerin draining.
Jon

quote:

Can you do a 5% pre wash immediately following removal of glycerin?

If your goal is to make a huge emulsion, this will be great technique! (As Jon says.)

The important thing about the glycerine pre-wash is that the ratio of glycerine to water stay high enough. As long as this is true, it prevents emulsion.

Is this only due to the mixing? As we remove glycerin prior to water washing. What does the glycerin do that prevents an emulsion?
Thanks for the comments.

quote:

Is this only due to the mixing?

Yes. The mixing is why the pre wash works as well as it does.

quote:

What does the glycerin do that prevents an emulsion?

It "breaks" the emulsion due to it's high affinity for water. Essentially, it pulls the water out of the emulsion. But, only if there is enough glycerine compared to the amount of water.

HTH.

More here...
http://www.biodieselcommunity.org/breakingemulsions/

I personally find that using Salt Water breaks emulsions with greater ease these days (and seems to do it much faster too).

-Graydon