Author Topic: I can't get my finished product to go crystal clear.....  (Read 1801 times)

Offline Bio-boy

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I can't get my finished product to go crystal clear.....
« on: July 31, 2015, 11:13:02 PM »
Strange batch.... 10/90 perfect, 50:50 perfect yet can't seam to get it to turn crystal clear on drying.
Not had this before. Plenty of heat and water removal yet it just won't turn.

Offline dgs

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Re: I can't get my finished product to go crystal clear.....
« Reply #1 on: August 01, 2015, 09:10:38 AM »
I always used to get crystal clear bio both before and after de-mething when I used a processor pump that was pretty weak.

Since moving on to much stronger pumps with eductors my bio either before or after de-mething is cloudy.
I have done a bit of research into this and the reason is that the agressive mixing caused by the pump/eductor combination mixes the bio/glycerol down to such a fine (molecular) level that it leaves suspended glycerol in the bio.

When I use an unmodified 1/2" eductor with the frankenpump (120) the nozzle velocity was calculated by someone on vod at 28 metres per second, the delivery line pressure was 71psi.

Even after drilling out the eductor to 8.5mms the pressure is now 34psi and flow is @65lts/min.

Having said all this, after water washing the product is crystal clear, if left to settle after de-mething it also goes clear after @ 1 week.

Bio Boy, I remember you bought a very strong pump (don't know if you use an eductor) so this might be your problem, the cloudyness will go either after washing or settling for long enough.

Someone once reported on infopop that it was possible to get the mixing too aggressive, but never said why. I wonder if this is the reason.
FOC water tests by Sandy brae or Karl Fischer for forum members.

Offline Julian

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Re: I can't get my finished product to go crystal clear.....
« Reply #2 on: August 01, 2015, 12:19:57 PM »
Good advise above.  But I have to say I've not noticed more cloudy batches after I'd installed Frankinpump.

Your bio will certainly clear in time, but it won't mean it's as dry as it could be.  I have had some success on one occasion circulating cloudy bio through a hardwood tower ... http://www.biopowered.co.uk/wiki/Dry_washing 

Also continued bubbling, if you have the facility, and provided the ambient humidity isn't high, may assist.
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Offline Rossey

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Re: I can't get my finished product to go crystal clear.....
« Reply #3 on: August 01, 2015, 09:50:15 PM »
Mines the same

Leave it a few days and it's cystal clear, filter
It and it's cloudy again.

Offline Bio-boy

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Re: I can't get my finished product to go crystal clear.....
« Reply #4 on: August 01, 2015, 11:25:53 PM »
Very strange but now sorted. Went back to the bio the following morning and it was crystal clear. In fact it was the best looking bio I have made so far with it being a pale straw colour. It must have something to do with the power of the pump as stated. Don't know how or why but the end result is still perfect biodiesel. :)