Biopowered - vegetable oil and biodiesel forum
Biodiesel => Chemistry and process => Topic started by: thewormman on September 30, 2013, 10:25:02 AM
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When I final filter I pass my bio through a j cloth before a 1micron sock filter but I am finding since the temp has dropped I am getting a wax buildup in the j cloth that is stopping the flow within a litre or so.
I have added coldflow 350 to it and taken the temp of a couple of litres down to 7C in the fridge and it is still there clouding it up mainly in the bottom of the sample.
Is this normal at this temp? I made sure this 180 batch was made with liquid oil glyc washed well dried 2 stage ASM non tit.
If I get this build up that stops the flow I will be here forever :(
Also if we have a cold snap and I get it in the tank if it wont go through a j cloth it will block my fuel filter :'(
How does everyone cold filter?
Thoughts on this at this temp?
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Some pics after 1.5 litres
(http://i250.photobucket.com/albums/gg244/zukenstein/Bio/scum/Photo1_zpsdd104e80.jpg) (http://s250.photobucket.com/user/zukenstein/media/Bio/scum/Photo1_zpsdd104e80.jpg.html)
(http://i250.photobucket.com/albums/gg244/zukenstein/Bio/scum/Photo2_zpseb44de7b.jpg) (http://s250.photobucket.com/user/zukenstein/media/Bio/scum/Photo2_zpseb44de7b.jpg.html)
(http://i250.photobucket.com/albums/gg244/zukenstein/Bio/scum/Photo3_zps5561e25e.jpg) (http://s250.photobucket.com/user/zukenstein/media/Bio/scum/Photo3_zps5561e25e.jpg.html)
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Just occurred to me when I do my water washing the bio is usually still warm right through the washing process do you think it's because it doesn't get a cold wash I am getting this?
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That's some pretty nasty stuff Dave.
Can you step-by-step your wash procedure please including type of washing, volume of water, duration etc
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Blimey I wouldn't expect that much from a couple of hundred litres and I don't water wash.
I do store my cubies in the coldest part of the garden to force any precipitation then filter off the clear stuff.
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Pops....it looks like something has gone a bit Pete Tongue with Daves washing....hence the need for some details and a breakdown of procedure
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Thanks Nigel this is what I am doing at the moment
OK after a clear pass on the 10/90 I drain the 2nd stage glyc and demeth then I acid wash with vinegar and 10L of water.
Settle 1 hour and drain water. Temp is still at about 70C then because of demeth temp.
Then I add 20L water and pump wash using a static mixer so no air is introduced for 2 hours. Settle and drain water after an hour. Soap is down to under 25PPM by then temp is still about 50C. I leave that overnight to settle before I drain.
Tank is well insulated so usually next day it is still warm. I have then been warming the bio again up to about 50C. Then I put in another 20L of water and pump wash through a Uri gellar diffuser for 2 hours to really agitate it, this seems to get out all the dark brown sediment that I had in my first batch that seemed to settle in the bottom of the cubies when it was finished and dried.
Finally I do a last pump wash for about four hours a bit belt and braces but water is pretty clear when drained. Soap test to check. Usually the temp is down to about 30C by then.
Then I crank the temp up again to 50C and pump through a Uri gellar diffuser with a hot air fan blowing in the top of the tank to dry.
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Well there doesn't seem to be too much wrong with your wash program.
There are a couple of things that may be considered not necessary by some. ie the heating of the bio back to 50C in the middle of the process and the use of the uri geller at that stage....but on the whole it looks ok.
Personally I don't re heat during the process and use my uri geller to flash off any moisture at the drying stage.
I bubble wash as you probably know and only pump wash right at the end.....normally when heated. The heat is then used to dry the bio when the pump wash water is drained off.
I'm sorry but I don't know what's causing your issues. Never seen it before with water washing. I'll be keeping an eye on this thread to see if anybody else has seen this before and how it was sorted out....or offers up any advice.
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well with all that washing I guess it's fair to say it aint gonna be soap, looks like hmpe but still a bit warm for that sort o quantity unless it's sterol glucosides,
What was the oil feedstock, is it your normal wvo?
What temp were you filtering the bio at?
Have you tried testing it, does it melt back to bio?
EDIT: Oh I forgot to say, I always thought a cold wash was best back in the days when I used to wash.
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I have had the last 2 batches do this. The first one had about 10% whites in it and I thought maybe that was the problem. So I did the next one with just nice liquid KTC oil that had only had 1 week use in a good Thai restaurant - same result :(
So I need to look at what they have in common. I did the same process as I had before through the summer with no problems the only difference is the temp has dropped.
Bio was filtered at ambient.
When I took some of the wax in a jar and left it on a rad in the house it DIDNT melt but stayed waxy just slightly runnier, and it was hot. That suprised me. You could see it clouding in the bottom of the bio when I cooled it down to below 10C but when you heated the bio to 15C+ it dissolved back into it.
Uncle h on VOD has the same problem and reckons its because he demeths, when he doesnt do that the problem goes away. So I am going to do some experimenting with Dr Peppers to try and get to the bottom of it. I do have some ideas having done some reading so will post up any positive findings.
Thanks
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i dont know much about the finer pionts of the bio process as i just do veg
but, i read alot and what crosses my mind is would slightly more chems being added help get shot of this, which also leads onto the settling stage to drop glyc is it a long enough settle? which also leads to your last comment about uncle H if he demeths he gets fatty mush after settle and filter, with meth left in the settle stage drops the fatty mush out with glyc...
just a thought dont shoot me folks :)
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Welcome to the world of HMPEs, I'm in the process of filtering out my last batch.
There was nothing when I decanted into 25ltr cans but 2 weeks later, a drop in temperature and Bingo.
Being used to it I just sheet filter and leave it, it's not very often I have to filter it again.
It's all part of the brewing experience.
I'm seriously thinking of building meself a proper centrifuge to clean the fuel just before I use it.
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gotto love sheet filtering 8)
http://www.biopowered.co.uk/forum/index.php/topic,1555.0.html
(http://imageshack.us/a/img199/7559/p23h.jpg)
(http://imageshack.us/a/img585/885/66yn.jpg)
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gotto love sheet filtering 8)
http://www.biopowered.co.uk/forum/index.php/topic,1555.0.html
(http://imageshack.us/a/img199/7559/p23h.jpg)
(http://imageshack.us/a/img585/885/66yn.jpg)
What has been filtered through these? Is this your finished bio filtering before use when the temp has dropped?
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I think that is RMs oil filter system he does not make bio.
This is some HMPEs I got last winter filtered out before final filtering. It does melt though. I use it in the lister at 50+C
(http://i1279.photobucket.com/albums/y521/dickjotec/5a156f76ab92a59dbcb37a51012ad1bd_zps8105f192.jpg)
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I think that is RMs oil filter system he does not make bio.
This is some HMPEs I got last winter filtered out before final filtering. It does melt though. I use it in the lister at 50+C
(http://i1279.photobucket.com/albums/y521/dickjotec/5a156f76ab92a59dbcb37a51012ad1bd_zps8105f192.jpg)
I've got a drum just like that in me shed.
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I think that is RMs oil filter system he does not make bio.
This is some HMPEs I got last winter filtered out before final filtering. It does melt though. I use it in the lister at 50+C
(http://i1279.photobucket.com/albums/y521/dickjotec/5a156f76ab92a59dbcb37a51012ad1bd_zps8105f192.jpg)
What temp does it melt at? Does it start to melt around 15-20C ?
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Welcome to the world of HMPEs, I'm in the process of filtering out my last batch.
There was nothing when I decanted into 25ltr cans but 2 weeks later, a drop in temperature and Bingo.
Jim what did the temp drop to when they started to form? Was it under 14C?
Is yours the same as showed up in my j cloth filter?
After lots of reading I am forming an idea of where this comes from.
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After lots of reading I am forming an idea of where this comes from.
I reckon it's the Palm, animal fats dissolved in the liquid oil.
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Welcome to the world of HMPEs, I'm in the process of filtering out my last batch.
There was nothing when I decanted into 25ltr cans but 2 weeks later, a drop in temperature and Bingo.
Jim what did the temp drop to when they started to form? Was it under 14C?
Is yours the same as showed up in my j cloth filter?
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Jim what did the temp drop to when they started to form? Was it under 14C?
Is yours the same as showed up in my j cloth filter?
The actual temperature is irrelevant it's the set point of the feedstock that counts.
Yes, mine looks the same as yours but left long enough it looks like Dick's, he's has dried ours is still wet.
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The reason I wanted to know the temp was because I am looking at a particular type of FFA that has a set temp it changes from liquid to solid but if you don't know don't worry thanks ;D
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The reason I wanted to know the temp was because I am looking at a particular type of FFA that has a set temp it changes from liquid to solid but if you don't know don't worry thanks ;D
Ah! but it ain't that simple, after transesterification the set point will be lower, then there's winterisers that can be added before the bio cools further lowering the CPP.
Btw do you mean fatty acid (triglyceride) or free fatty acids that we neutralize at the beginning of each batch?
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Ah! but it ain't that simple, after transesterification the set point will be lower, then there's winterisers that can be added before the bio cools further lowering the CPP.
Btw do you mean fatty acid (triglyceride) or free fatty acids that we neutralize at the beginning of each batch?
Mmmm...
Ok I will keep reading! :)
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Sorry I don't know what temp it starts to melt at as it is stirred into hot liquid oil at about 35-40c in the fat melting tank. The oil is then filtered into the main heating fuel tank and raised up to about 50c.
As a point of interest the large mass of ?HMPEs shown formed when using acetone in the reaction. The acetone did improve the process but more of the HMPEs were formed, in cold weather, than without the acetone.
Dick
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Ok thanks for the info Dick
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Btw do you mean fatty acid (triglyceride) or free fatty acids that we neutralize at the beginning of each batch?
Free fatty acid I meant I understand these are not really converted very well with alkaline catalyst and what isn't converted supposedly combines with any water to form soap. Have I got that right?
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Btw do you mean fatty acid (triglyceride) or free fatty acids that we neutralize at the beginning of each batch?
Free fatty acid I meant I understand these are not really converted very well with alkaline catalyst and what isn't converted supposedly combines with any water to form soap. Have I got that right?
Correct, a titration is used to measure the level of ffa's in your feedstock thus allowing you to add the correct weight of catalyst above the chosen base figure.
FFA's are immediately turned into soap when the methoxide is introduced into the reactor.
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The only time I've seen this is when I demeth my bio before settling. I found if I didn't demeth, then just did a prewash bubble and settle it never showed.
Nowadays I mainly pump wash or bubble wash, depends what mood I'm in.
Dawson
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I leave my fresh bio for at least 7 days after final bubble demeth.
At the moment HMPE's form on the sides of the 120 litre drum. A couple of days before using the bio I give the batch a stir and I get a good snow storm (wax crystals are about 1.5mm dia) this I leave to settle and after a few days the bio is ready for filtering (currently I use a 100 micron ez strainer in one of my pukka buckets. The dregs at the bottom of the drum are HMPE's with a little glyc /soap.
My feedstock is mainly rapeseed some soya and a little animal fat.
Slabs