In processor titrated water wash method

[nigelb]

this method sounds very interesting.where can i buy the acids needed to give this a got

thanks william

If it's not too late William, Barry could supply you with any acid you like and put it on your pallet.

Nige

[julesandtash]

With this system you can use any acidic liquid you just need to do the titration with the same solution.

Paul

I would recommend not using nitric acid though - although the risks are absoutely minimal, it is not a good idea to mix nitric acid with organic materials, particularly glycerin.

Concentrated sulphuric is probably the cheapest option you could use.

As Carrington says, it doesn't really matter which acid (except Nitric - as above) that you use, you just need to make up a tiitration fluid with it so you can calculate how much you need to add to the batch. The weaker acids like vinegar will need much higher volumes that the stronger ones (although teh strong ones need diluting in water first before they are added).

[Tony]

I dunno about that, I added fuming Nitric and Sulphuric to mine and I've not seen any Glyc since!  (Or the shed, or the windows at the back of the house) 

[nigelb]

This is one for keith really. With such a short wash cycle ie 2 washes...does this completely deplete the amount of methanol within the biodiesel. Have you used your alcohol tester to check on the percentage of methanol left behind.

Nige

[K.H]

This is one for keith really. With such a short wash cycle ie 2 washes...does this completely deplete the amount of methanol within the biodiesel. Have you used your alcohol tester to check on the percentage of methanol left behind.

Nige

I never gave that a thought Nigel,good thinking,i intend doing another batch tomorrow to double check my method so i will check the washes for methanol as well

[Head Womble]

What indicator do you use, I assume it's different to the turmeric I used to use for titration.

I was going to add a cone to thebottom of my settling tank so I could go back to water washing,
but I think I'll give this a go as it's less work, less time and less modifying of my system.

[K.H]

The Bromophenol from Nigels soap test kit

[Carrington]

Hi all
This system can also be used with the dry wash if anyone wants to give it a go.
When using this way with dry wash you add the acid first to neutralise then de-meth , the salt that's created is bigger than the residual alkali so will settle quickly , probably fast than the time to de-meth.
Any filter system used after should last a lot longer. This is something I did in the factory and it made it possible to get much more bio through the filters without changing.
Maybe I should keep stum about the dry wash

Paul

[julianf]

The main thing that's put me off water washing in the past was the energy required to then dry the bio.

Not that ive done calculations, but i felt that re-heating the bio from cold and then taking off the water must take more power than just keeping it hot at the end of the reaction to demeth.

It seems that this method may require so little water so as to be able to maintain the temperature to some degree.  Jules mentions this above.

Could this reduce the total energy consumption per batch then?




Somthing else i thought when reading through this thread -

Water washers have always mentioned lack of HMPEs as a bonus of water washing.  Its been hard to tie this down, but my own conclusion was that washing with cold water possibly allowed the HMPEs to come out of solution, and get removed with the water.

If this is the case, then maintaining the temperature with the low-volume water washes may remove this function?

[K.H]

I read Julians post while making a batch today so i took a sample from last weeks titrated wash,i used a higher % of water than Jules and it was cold water straight from the tap,i also never bother reheating at any stage after the initial 64C,not sure what Jules does so my bio may be at a lower temp.
Anyway i  stuck it in the deep freeze,below is the bio at -8



No sign of HMPE,s and when back to room temp still no sign



Not conclusive i know but seems to be ok with my oil

[julesandtash]

Good stuff Keith.
I have a batch brewing right now - just waiting for the acid wash to settle then will be a couple of water washes then bubble overnight.

I use cold water straight from the tap. I could use hot water too as I have mains pressure hot water on tap in the processing area. Maybe I should try a batch with each.

[Julian]

Going to give this a go, but need to free up settling tanks to do it.

Any how, to refresh my rather poor memory, I just reread Jules's description on page two of this thread.

Jules, I was wondering if would it be prudent to add a warning where you twice talk about diluting concentrated sulphuric acid.  I was told that you should add the acid to the water and not the other way round.  I believe if you get it wrong you can get a violent reaction as the heat produced boils the acid.

[K.H]

Ok this is the method i used today,we tried universal indicator so we could tell when it changed to pH 7 as we wanted it neutral,we also tried methanol instead of IPA because the IPA we had was acidic


280 LITRE BATCH

(1) Titrate bio

(2) Titration fluid: white vinegar

(3) 25 ml of Methanol and some Universal Indicator,added 10 ml of bio shake, Green to Blue

(4) Then add the titration fluid in drips until the colour changes to green/yellow

(5) Multiply the result by the batch size to get the amount of acid needed
e.g. if 0.1ml vinegar used to change colour to neutralize 10ml bio, 10ml vinegar neutralizes 1L 10x280 = 2.8L vinegar

(6) Add to 30 litres of water and mix with the bio for 25 minutes

(7) Take sample for reference

Sample just taken


Settled


( 8 ) Allow to settle for 1 hour,then drain the 30 litres

(9) Then add 30 litres of water and mix for 5 minutes

(10) Take reference sample

2nd wash settled


50/50 of 2nd wash


(11) Leave to settle for 15 minutes

I tested the raw bio for methanol as well,after the first wash i got a reading of around 300 ppm and after the second 100 ppm,so by the time i do the third and final wash it should around zero.

The cost of the vinegar for a 125 litre batch would be just under £2,how does that compare with sulphuric? (im sure vinegar can be got cheaper i had to buy Sarsons as it was the only one available)

Any comments on the method or use of "universal" and "methanol" ?

[william crosby]

hi Keith does it matter what type of vinegar used as i have just bought 5 Lt's from cosco for £2.05 and there is no vat but its not white vinegar

[K.H]

No it shouldn't make any difference,I Titrated with White so just bought the same,it was just what was here at the time