Emulsions during washing and cloudy bio possibly as per Greenchef's thoughts.

[Julian]

It seems to be the season for problem batches.

My last batch seemed to cling onto water, nearly cleared after two days bubbling and finally cleared after pumping through the dry wash tower.

This batch, however, is proving to be a right nightmare.  I dried it to 90°C, much higher than normal and had to add ASM after the second stage to get a cloudy 3/27 with no dropout.  Glycerin pre-wash went OK, but even with the addition of sulfuric acid for the first pump wash, formed an emulsion.

Additional acid wouldn't break it but glycerin did resulting in a very dark bio.  I must have done 7 or 8 pump washes using the Mono pump so as not to churn things up too much, but on the last wash got another emulsion!  I broke this one by heating and drying with the condenser again to 90°C (way higher than my normal) over an extended period until no water was being evolved.

At this point I pumped out to the settling tank and bubbled over night as normal.  Soap tests showed approximately 50ppm (I find the colour changes very difficult to distinguish at low ppms) but the bio remains very cloudy.  A 50/50 shake test creates  an emulsion which breaks of it's own accord overnight, leaving clear water a thin emulsion layer and lighter coloured but still very cloudy bio.

Decanting the light coloured bio and adding water absorbing granules gives a tiny top layer of clearish bio which may have happened anyway without the granules, and the granules show little or no signs of having absorbed any water.

I've tried piping the dry wash tower to suck and discharge from the same barrel and circulated the bio through it but it made little difference.

At this point I'm stumped.  My memory is pretty poor but I've vague recollections of someone suggestion MSG as a possible culprit for this type of issue ... anyone any ideas?

[Manfred]

Judging by the views you're on your own with this one Julian. I can't help mutch  either being only one 18 months into brewing. However I did a batch on Christmas Day like you do, but de methed and settled instead of washing. All went well with the batch so bubbled overnight after reclaiming 3 litres of methanol. Next morning I saw my batch full of hmpe's. It had gone sub zero overnight. Nothing better to do I j clothed them out and left it to settle. My wood shavings are in a bucket with 2 3mm holes in the bottom to drain into a 40 litre tub with a 1um bag filter hanging inside. After filling it up I drew off a sample into a jar only to see cloudy bio. What came out of the shavings was crystal clear. Eventually traced it to the small amount of bio left below the syphon level had waxed on me contaminating all the bio that was added to it. Just wondering if with you taking the temperature higher than normal you've had something similar happen. What does it look like if you j cloth a sample.

[Chug]

I've read it twice and I'm not sure what you are saying your problem actually is Julian, it seems like you are saying after all the messin about that the bio is still cloudy?

If this assumption is correct, have you warmed a sample?

[Julian]

I've read it twice and I'm not sure what you are saying your problem actually is Julian, it seems like you are saying after all the messin about that the bio is still cloudy?

If this assumption is correct, have you warmed a sample?

Sorry, it was a rather rambling post ... in essence I think there's something in the feed stock that appears to be holding on to water resulting in easily made emulsions and a cloudy end product.

[Julian]

Judging by the views you're on your own with this one Julian. I can't help mutch  either being only one 18 months into brewing. However I did a batch on Christmas Day like you do, but de methed and settled instead of washing. All went well with the batch so bubbled overnight after reclaiming 3 litres of methanol. Next morning I saw my batch full of hmpe's. It had gone sub zero overnight. Nothing better to do I j clothed them out and left it to settle. My wood shavings are in a bucket with 2 3mm holes in the bottom to drain into a 40 litre tub with a 1um bag filter hanging inside. After filling it up I drew off a sample into a jar only to see cloudy bio. What came out of the shavings was crystal clear. Eventually traced it to the small amount of bio left below the syphon level had waxed on me contaminating all the bio that was added to it. Just wondering if with you taking the temperature higher than normal you've had something similar happen. What does it look like if you j cloth a sample.

I'm pretty sure it's nothing to do with HMPE's, my shed is very well insulated and hasn't dropped below 10°C throughout all of the above.

I don't think drying the feed stock to 90°C would have any effect ... it reaches far higher temperatures when used for cooking. I used to dry the bio to 80/90°C but reduced it to 75°C after having HMPE problems.  I never had the same problem before dropping the temp.

My dry wash tower has pretty good filters built in in the form of felt carpet underlay above and below the media and running the bio through that made no discernible difference.

Having left samples for a couple of days, they are showing signs of clearing slowly.  The sample with the water retaining granules is clearer than others.

I'm sure there must be something strange in the oil that's causing this.

[Julian]

KH, I'm having vague recollections that it was a chef contact / friend of yours who suggested MSG may have some effect on the process ... ring any bells?

[Chug]

Have you warmed a sample?

[Julian]

Have you warmed a sample?

Yup, to break the last emulsion I took it up to 90°C and ran the condenser until it stopped dripping ... dam stuff was still cloudy.

[greasemonkey]

KH, I'm having vague recollections that it was a chef contact / friend of yours who suggested MSG may have some effect on the process ... ring any bells?

I think it was Greenchef.
Is this the post you were talking about?

http://www.biopowered.co.uk/forum/index.php/topic,1002.msg10504.html#msg10504

[Julian]

KH, I'm having vague recollections that it was a chef contact / friend of yours who suggested MSG may have some effect on the process ... ring any bells?

I think it was Greenchef.
Is this the post you were talking about?

http://www.biopowered.co.uk/forum/index.php/topic,1002.msg10504.html#msg10504

Genius, thank you!

It wasn't MSG but it was about water retention and making emulsions.  The link he quotes is broken but once I've learned how to pronounce it I'll do some Googling on mucilaginous fibers.

Although I mix my oil I think I can pretty much tie the feedstock down to one new supplier.  Great oil, very clear, no whites at all and titrates at 0.5 NaOH.  But if this is going to be the norm then it may be destined for ebay in the future!  I'll inquire what oil they use next time I collect.

[greasemonkey]

If it proves to be the issue, then it might be possible to find some kind of test for it.
If it's really good clean liquid oil, it's worth a bit for veg runners, or would have been a few months ago. Seems there's a glut of it right now.

[Julian]

Done a little reading.  Most of it is on the nutritional and medicinal benefits, which seem numerous, but there's nothing I can find on the effects on bio.

This page gives a good overview ... http://www.botanical-online.com/english/mucilage.htm

This paper was the most informative ... http://cdn.intechopen.com/pdfs-wm/41676.pdf  it mentions water retaining and emulsifying properties, but the science is way beyond me.  It certainly seems to fit the bill, in that you can dry the bio with water retaining granules until it's clear, but add more water and mix and you get an emulsion again.

Elsewhere there was mention of soya containing mucilaginous fiber, so the culprit could possibly be soya oil.

Greenchef describes it as a gel when used in cooking so I wonder if chilling and filtering would remove it ... might give that  a try.

[K.H]

Might be worth putting @Greenchef in the thread title, i see he was on line a couple of days ago, he might have further thoughts?

[Julian]

OK

[Julian]

And so it goes on.

I put a sample in the freezer and then filtered it through news paper (being the finest paper I could think of).  Very slow, it took circa 12 hrs to filter ½ a jam jar, the sample was crystal clear, but there was no obvious deposit on the news paper.  I'll wait for the balance of the sample to filter and then inspect the newspaper more closely.  Chilling the sample the way I did was rather pointless as it warmed up before it started dripping through the newspaper!

A vigorous 50/50 shake test of the filtered sample, didn't create an emulsion and split to wet bio and clear water within a few hours.  I'll leave the shake test longer to see if the bio clears.

Still not really sure what's going on but it does all seem to fit Greenchef's thoughts.