Cold filter troubles

[Jamesrl]

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

I've got a drum just like that in me shed.

[thewormman]

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

What temp does it melt at? Does it start to melt around 15-20C ?

[thewormman]

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.

[Jamesrl]

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.

[thewormman]

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?

[Jamesrl]

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.

[thewormman]

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 

[Jamesrl]

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 

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?

[thewormman]

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! 

[Dickjotec]

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

[thewormman]

Ok thanks for the info Dick

[thewormman]

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?

[Jamesrl]

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.

[db]

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

[slabster]

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