Glycerin appears to be tied up in the bio

[Julian]

I may yet get plonker of the week award ...

Running a batch today, all went very well got a clear 3/27 after the second stage.  Added back the first stage glycerin and demethed quite heavily.  Added 7% water and ran the pumps for 10 mins.

I usually take samples immediately before ending an operation so I have a representative sample of what's happening in the processor.  In this case I'd taken a sample about 5 mins after adding the water and thought that would be good enough.

Well, it wasn't!  When I came to drain the glycerin it just kept on coming.  The bio and glycerin appear to be bound together and all attempts to separate them have failed.



Above, left to right ... Sample taken 5 mins before stopping pumps (completely normal separation etc), sample with additional methanol and ASM added, 50/50 mix of this batch and bio (starting to separate), 50/50 mix this batch and water (appears to be miscible)




Above, left to right ...  the 50/50 mix this batch and water (I can't even get photos right at the moment!), strong salt solution (now showing signs of dark liquid settling to the bottom), methanol added (appears to be miscible), and just at the edge of the photo strong sulfuric added (no apparent change)

The dark pointy test tube top left of the last photo was given a good human centrifuging with no change.

I done a 7% water wash scores of times and never had this happen and I find it strange that an extra 5 mins of mixing could result in this.  Anyone any ideas please?

[willbuild]

must be oil, metoxide,contaminated water or container or you put the wrong glycerin back in (we all have plonker mouments).
try and eliminate each of the above. good luck

[Chug]

Had similar myself, fixed it two different ways, you mention heavy demeth so I'm leaning towards adding some, if adding meth doesn't fix it, try adding some more wvo.

[julianf]

If you boil off the water from a sample, what happens then?

[Julian]

must be oil, metoxide,contaminated water or container or you put the wrong glycerin back in (we all have plonker mouments).
try and eliminate each of the above. good luck

Each can eliminated as the batch only went wrong in the last 5 minutes.  It's a 90% chance that it's some form of emulsion.

Had similar myself, fixed it two different ways, you mention heavy demeth so I'm leaning towards adding some, if adding meth doesn't fix it, try adding some more wvo.

Tried adding methanol, second thing I did, and that appears to have had no effect.  If it's worked for you in the past I'll give it another go, perhaps with a bigger volume.

Haven't tried adding oil ... is that likely to work?  I'd have thought with water now in the equation no further reactions would take place, but I'll give that a go too.  Watch this space.

If you boil off the water from a sample, what happens then?

Like the thinking behind that idea.  I'll try a sample, but it's one hell of a lot of water to distil off and probably not economically viable.



Just had a look at the samples a couple of hours after making them and surprisingly the most promising two are the 50/50 mix with good bio and the salt.  Both are showing signs of splitting.  The added bio appears to have three phases, fairly clear bio at the top, very cloudy below and a bigger than expected layer of glycerin at the bottom.  The salt sample is splitting to glycerin at the bottom and the brown gunge you see in the photo above.

Perhaps less salt in more water may be worth a try.

[Glycer-rides]

I would add some meth to a jar sample (after the water is removed, if possible).

I would also (read 'did') quit that type of process; adding back the glyc / heavy demething / adding a water prewash.
It's easy enough to modify a plant to make glyc washing more useful than reclaiming back meth, I think.

[Julian]

I would add some meth to a jar sample (after the water is removed, if possible).

I would also (read 'did') quit that type of process; adding back the glyc / heavy demething / adding a water prewash.
It's easy enough to modify a plant to make glyc washing more useful than reclaiming back meth, I think.

It's economically viable to reclaim methanol and to a degree there's a bit of "I've always done it that way" involved too (hope Nige isn't reading).  And a 7% water pre-wash, has been for very many batches, good preparation for titrated acid washing, normally it all works very well for me.

Glycerin washing is ok this time of year, but with my set up in winter, I have to remelt 20 ltrs of the stuff before I can use it.  If I ever get round to building a new setup, I'll include a heated pretreatment tank running on economy seven, which would make glycerin washing easy as pie.

[Head Womble]

I used to sometimes suffer from a milk chocolate looking thick emulsion when adding a 7% prewash after WBD,
it was ok to start with and then the sound of the pump would change as it struggled,
I found adding some of the reclaimed meth back in fixed it,
but your samples don't look the same as mine did.

[Glycer-rides]

I would add some meth to a jar sample (after the water is removed, if possible).

I would also (read 'did') quit that type of process; adding back the glyc / heavy demething / adding a water prewash.
It's easy enough to modify a plant to make glyc washing more useful than reclaiming back meth, I think.

It's economically viable to reclaim methanol and to a degree there's a bit of "I've always done it that way" involved too (hope Nige isn't reading).  And a 7% water pre-wash, has been for very many batches, good preparation for titrated acid washing, normally it all works very well for me.

Glycerin washing is ok this time of year, but with my set up in winter, I have to remelt 20 ltrs of the stuff before I can use it.  If I ever get round to building a new setup, I'll include a heated pretreatment tank running on economy seven, which would make glycerin washing easy as pie.

Methed NaOH glyc. is not a problem, seasonally.
A simple addition, pre-pump, is a T'd in up-ended hdpe carbouy with the bottom cut off. This can be back-flushed with hot oil from the processor, if needed.
Also good for introducing other stuff; watery meth, hmpes, at appropriate times! And not, at no time, methoxide, you understand...

[Dickjotec]

I had something similar. Drained glyc and it did not stop. I drained it all into cubies with the intention of getting it hot and putting it back in when I had more time and over a few days it separated and I could pour the bio off. Got more glyc than normal but did not have to do anything to the bio other than bubble and settle. Mine was a bit 'jelly' like from the processor.
Might be worth getting it out of the processor and waiting?
Good look with it.
Dick

[neisel]

I had this a while ago, just left it to cool down over a couple of days & it separated - http://www.biopowered.co.uk/forum/index.php/topic,1168.0.html .

[nigelb]

(hope Nige isn't reading).

No....I'm not!

[julesandtash]

Glycerin washing is ok this time of year, but with my set up in winter, I have to remelt 20 ltrs of the stuff before I can use it.  If I ever get round to building a new setup, I'll include a heated pretreatment tank running on economy seven, which would make glycerin washing easy as pie.

I wonder where you got that idea from.
It actually works very well.
I now make sure that there is enough room in there for a full batch worth of glyc. As I make a batch I throw the glycerol into the pretreat tank whilst still nice and warm. My pretreat tank has a pump on it separate to the processor so I can circulate the contents to mix it all up then leave to settle.
Glyc wash stays in there with the heat off until the night before I need the oil when I drain the glyc and then reheat the oil to processing temperature ready for the morning.

[Julian]

Glycerin washing is ok this time of year, but with my set up in winter, I have to remelt 20 ltrs of the stuff before I can use it.  If I ever get round to building a new setup, I'll include a heated pretreatment tank running on economy seven, which would make glycerin washing easy as pie.

I wonder where you got that idea from.
It actually works very well.
I now make sure that there is enough room in there for a full batch worth of glyc. As I make a batch I throw the glycerol into the pretreat tank whilst still nice and warm. My pretreat tank has a pump on it separate to the processor so I can circulate the contents to mix it all up then leave to settle.
Glyc wash stays in there with the heat off until the night before I need the oil when I drain the glyc and then reheat the oil to processing temperature ready for the morning.

Since I first thought of making a square processor to save space, so about three years ago!  I've wanted to take advantage of economy seven since I first started making bio, so over five years ago.  I just haven't got round to putting the ideas into pratice ... it's a little like building an extension.

[julesandtash]

So after about 14 years you should be most of the way there then - only another nine to go.
I'm hoping I will have completed my hot water heating of the whole system by then, with the heat being provided by bio of course, well before then.