Posted 19 May 2006 03:40 PM
I didn't take the time to read this thread in its entirety, but I CANNOT underscore, from personal experience, the crucial role heat has on emulsification and drying.

I've had a continual middle layer of butter between the water layer and the biodiesel in the standpipe drum. It's been annoying, and growing gradually from batch to batch, each batch yielding a smaller amount above the layer.

I've tried everything, setting buckets of the crap aside, and to no avail. It never did settle into the subsequent batch. I've also had poor luck with drying and filtering in the next drum (I built a second drum lacking water exclusively for drying) because I was probably transfering into it small amounts of the middle layer in my zeal to get more yield.

Well I finally anted up and bought www.b100supply.com's drum heater (looks like a weight belt) and insulation which had been mildly suggested (only) as one of many possible solutions.

In my opinion, it's the ONLY solution because while you're breaking the emulsion, you're simultaneously taking the very last step toward having perfect, usable biodiesel. Nothing's been added (glycerine or methanol) that after needs to be removed.

Here's what happened:

After misting about a half dozen times, then bubbling, I applied heat. Cooked it, in fact, and I now realize that I should have kept the temperature down somewhat.

Anyway, the following magically happened while I slept:

1. the middle layer between the water and the biodiesel disappeared entirely. It was a razor sharp border between the two, and the standpipe worked perfectly as advertised when draining.

1a. Even the crap normally associated with the top (moths and chiggers and dog hair) was at top of the water layer instead of being at the top of the BD layer.

2. the biodiesel had actually dried in less than five hours. I mean COMPLETELY. Even with the water layer below it. Crystal clear.

3. it worked perfectly with NO filtering. I know this because I my fuel filter in my 300D wasn't full of crap and has lasted longer.

So, I say, throw the stupid water filters that don't pass in any volume in the trash, and fork up the cash for the drum heater. I can't rave enough, because the complications of emulsification/washing/drying was completely turning me off and I was just a little shy of giving up the hobby entirely!!

And when you're not making biodiesel, you can always wear the heater as a fashionable body warmer and weightloss device (I AM ONLY KIDDING--DO NOT TRY THAT AT HOME).

Dana,
What temp do you suggest as ideal?
Have you tested the fuel that comes from breaking an emulsion to know if it is of equal quality to the rest of the batch?
THanks,
Andrew

try adding salt to your "butter" mix well let set. 1/2 to 1 tsp per ltr.

Thanks for the info in this forum on breaking emulsions. I had over 40 gallons of creamy yellow mush and added salt and heat, and now have biodiesel and water. Now can someone direct me to a place that will sell me a drum heater or dip rod? It's getting cold in upstate New York, even with the global warming effect.

No Pete, you're likely to have biodiesel with salt in it. I"d be very leery of using salt to break emulsions because of some things I observed with that.

Use glycerine= it works very well and it's easy to wash out afterwards. Salt isn't, I don't think.

Mark

Mark, thanks for the warning. I'm going to wash this salty biodiesel and I'll let you know what happens. So, I can just add some glycerin back into the mix and heat it, and the emulsification will break up(not that it's ever going to happen again, of course!)?