Glycerol Pre-Treating in Bulk.

[dgs]

I thought I would take advantage of the warm weather today. I had an IBC of good oil (700 litres) and 100 litres of glycerol, some used once for pre-treating and some virgin ex -process.

Mixed for 1 hour with my jabsco self priming pump, about 40lpm (not really ideal for the job, hence my post asking for another TAM 120)

Just checked now, 4 hours after stopping the pump and nice clear oil on top with the glycerol at the bottom.

I have actually done this before with an IBC that I used to keep in my polytunnel.

The extra tap on this IBC is set at the 350litre mark, so I can add more glycerol or oil and re-pump the contents.
When the glycerol height gets to 300 litres I will run some off and add fresh.

It just saves doing a separate glyc wash for every process.
I don't know how long I can do this for as the weather turns colder but we will see.

[Manfred]

Why don't you get a Clarke bip1000. £60 new and you could run 4 for the same power consumption. Or add it to the Jabasco and get 80Lpm turnover.

[dgs]

Good idea Manfred. The only thing is that when I come to add more glycerol or oil, when the bottom tap is opened to the pump the glycerol is really thick so I need something really powerful to start the mixing process.
After the initial mixing then it is easy.

[Manfred]

Dave. PM sent. Hope you see this before 18.00. Gaz.

[dgs]

Sorry, missed it. Just looked on forum now.I pm'd anyway.

[dgs]

I just added another 100 litres of oil and 70 litres of glycerol and re-mixed, all seems to be going well so far.

It's just short of the 1000 litre mark in that IBC so next time I have some glycerol I will mix it in another.

[Manfred]

What effect is it having on the titration doing bulk pre treating. You know that it's going to be very dry if nothing else and no glycerol carry over.

[dgs]

Good question Manfred, I don't know is the answer.

I use low titration oil for processing, so I would assume the oil doesn't now show any titration. The glycerol pre-treatment using the normal amount of glycerol from the last process can usually neutralise oil that titrates up to around 2.0 (depending on amount of glyc and how chemical rich it is) after that the normal amount of glycerol will struggle to achieve zero titration unless it is enhanced with a small amount of methoxide.

What I am saying is that if a glycerol pre treatment is going to be done then ideally it needs to neutralise all the ffa's in the presence of glycerol so all the resultant water is absorbed.
oK, it will help the process even if it reduces the titration but it is a lot of work to still leave the oil with a positive titration, just to produce more water when the methoxide is added.

I will titrate it now and report.

[dgs]

Suprisingly enough Manfred, it still has a titration of about 0.5 (KOH)

This oil is not the best that I use for my road fuel process but even so I'm suprised by the result.

Either this oil originally titrated higher than I thought, or (as I suspect) the ambient temperature glycerol mixing at around 25degs does not allow as much of a chemical reaction to take place. If this is the case this type of ambient mixing even at this time of year is not going to be as useful.

[Manfred]

0.5 is still low enough to get straight into processing and also no or little drying needed.

[dgs]

Thats true Manfred. The other reason I'm thinking is that the gentle mixing with the jabsco isn't sufficient.

[dgs]

0.5 is still low enough to get straight into processing and also no or little drying needed.

That is true Manfred. The other reason the oil still shows a small amount of FFA's is possibly the over gentle mixing with the jabsco.
i will have to re-mix for 1 hour with Rosseys 120 when it comes.

[dgs]

I ran some oil off one of the IBC's yesterday where the oil is now stood on glycerol. I added some more oil and glycerol. In the absence of the TAM 120 (soon in transit, I hope) I used compressed air from the small compressor via the bottom tap to mix the contents.

It did an excellent job, I checked last night with the torch and the glycerol layer had settled nicely.

[dgs]

I've continued to pre-treat the oil for road use in the 600 litre IBC. I let the glycerol build up to 100 litres or so, then when I have more I run some off before I re-mix. When I have more oil I sometimes re-mix with the glycerol already in the tank.

I now use a 1/2hp compressor for the mixing which is a lot cheaper to use than the TAM120.

Two local brewers who don't pre-treat give me their glycerol, so sometimes I have 50 to 60 litres to go in.

Some of the oil can be treated 3 or 4 times doing it this way. The appearance of the oil is totally transformed doing this, also the oil in the IBC presently gives 7.5mls dropout with a 10/90

I used 75% of base catalyst for my last process and had a pass in one stage using 11% methanol.

I will post some photo's later today.

[dgs]

Here is the photo of my IBC. The glycerol layer is clearly visible at about the 30 litre mark. The oil in the cubie is from the IBC, it wasn't dark to start with but considerably darker than it is now.