Here is a short video clip of the glycerol settling superfast out of biodiesel after a whole batch demeth.

You can see it happening before your eyes after only a few seconds and after 1 minute it's clearly visible but unfortunately an almost full memory card only allowed just over 3 mins video time.

The glyc took approx 6 mins for the main bulk to settle out, within half an hour the bio is clear.

Mahli got a new phone and I asked her to video it for me, not the best quality clip, but now we know what to do to get a better clip next time.

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Thread about my whole batch demething method here
http://www.vegetableoildiesel.co.uk/forum/viewthread.php?tid=11912


[Edited on 11-5-2009 by Chug]

Impressive chug.
Once you have settled most of the glycerol and decanted it do you pump the bio through all you pipe work to flush out any that has settled in it?
bob

Bob.

I only drain the pipework on the pump and venturi side (just one valve to open at the bottom) as soon as I stop demething, and just make sure I drain the glyc within the hour before it starts to set solid.

I once had some glyc go hard in some pipework and had to remove the pipe and use boiling water to clear it!

And I've just found a partial blockage in my venturi which explains why my methoxide took twice as long as normal to suck in and why demething took longer than usual over the w/end.

Chug, Your Glyc. take a long time to drop out, lol, I drained the Glycerol off after 10mins on my last batch, Very late at night so I had to do it.
I got a little more soap in the settling tank but who cares.

I flush my pipes out after demething with the Bio by pumping it into my settling tank I then open the drain tape and drain the last of the bio. I leave the valve open with a pot under it. I've not had problems with solid Glyc.

Any remaining glycerol in the bio settles out in the settling/bubbling tank along with the soaps.

I wash out the "reactor" with around 5lt of crappy oil and use this every time I brew.

I never get blocked pipes this way.

I also leave the "taps" open at the end to drain into a tub.

found the pic of the glyc-worm I once had to remove from my pipework


[Edited on 11-5-2009 by Chug]

If I can suss out a quicker way of settling the glyc I'll let you know Jim, but for now I'll just have to live with it!

I also get a little glyc in my settling tank, and now that it sets solid I've taken to stuffing a piece of pipe in the bottom drain valve to stop it clogging.

Did GL have a system using high voltage
It is on his site.
bob

Yes, electorstatic seperation.
Unless you are fully aware of the dangers 10,000volts+ with next to nothing amperage I'd leave it alone. You only need a small amperage to leak through and it could be "good night viena".

I was thinking as the methanol has been removed it would be safer.
But seeing how fast it is settling any way is it packable for the few minutes it would save
bob