In processor titrated water wash method

[Head Womble]

It's good method for new brewers, as if you do make a soapy batch you can wash with confidence.
In may ways it's fool proof, but you always get one fool that can mess anything up.

[mikethebike3]

After 7 previous batches with varying degrees of minor problems (but ultimate success), I just tried my first batch using this titrated water wash, and I failed :-(
I'm using universal indicator and mixed it with meth as per the wiki, it turned a little yellow so I added a drop of KOH reference solution which turned it nicely green, no probs.
Then when I added my bio it stayed green, and no amount of shaking or threatening it made any difference.  I repeated the process with the same result.  Just to make sure I didn't have a dud indicator I added a few more drops of KOH reference and it duly turned blue.
I should say that I processed using 4 stages, with each 10/90 returning less unprocessed oil until I got a pass.  I deliberately do this as it's not a lot of extra effort and I know it should minimise soap production, but I wasn't expecting ph neutral!
Any suggestions?  I've emptied it into my settling tank as I have to do another batch, but does this mean I could have washed it in the processor (as if I'd added acid) without fear of forming an emulsion?
Any insights gratefully received!
Mike

[Julian]

Hi Mike,

Welcome to the wiki and forum ... what took you so long!

Best test you could do is to do a say, 10% water shake up test.  Shake the b'Jueus out of it, that should give you some idea of what in-processor washing will do.

[mikethebike3]

Thanks for that Julian - are you ALWAYS here?
I'll give it a whirl in the morning and report back.
Mike

[Julian]

Not ALWAYS.  The PC is usually on if I'm at home and I'll check the forum when I pass the PC!

I've been looking at exactly the same thing this evening.  I did a 7% water wash with the glycerine (won't need glogs for a few months hopefully) and tried a shake up test afterwards ... results don't look promising, so I'll probably have to go back to titration for soap and add acid.  Strange when I keep reducing the ASM.

[Head Womble]

Not ALWAYS.  The PC is usually on if I'm at home and I'll check the forum when I pass the PC!

I've been looking at exactly the same thing this evening.  I did a 7% water wash with the glycerine (won't need glogs for a few months hopefully) and tried a shake up test afterwards ... results don't look promising, so I'll probably have to go back to titration for soap and add acid.  Strange when I keep reducing the ASM.

This suprises me, I got away with a 10% water wash with only the second stage gly pressent on my last batch, and I run the eductor while washing.

[Head Womble]

After 7 previous batches with varying degrees of minor problems (but ultimate success), I just tried my first batch using this titrated water wash, and I failed :-(
I'm using universal indicator and mixed it with meth as per the wiki, it turned a little yellow so I added a drop of KOH reference solution which turned it nicely green, no probs.
Then when I added my bio it stayed green, and no amount of shaking or threatening it made any difference.  I repeated the process with the same result.  Just to make sure I didn't have a dud indicator I added a few more drops of KOH reference and it duly turned blue.
I should say that I processed using 4 stages, with each 10/90 returning less unprocessed oil until I got a pass.  I deliberately do this as it's not a lot of extra effort and I know it should minimise soap production, but I wasn't expecting ph neutral!
Any suggestions?  I've emptied it into my settling tank as I have to do another batch, but does this mean I could have washed it in the processor (as if I'd added acid) without fear of forming an emulsion?
Any insights gratefully received!
Mike

Have you tried a 7% water wash (with gly pressent) and then doing 10% water washes.
You should get away with this if you're producing very little soap.
Try it on a small sample first though.

[Julian]

And when it doesn't work you can dump 200 ltrs in my back garden!

[Kevin]

I'm new here and at a larger scale refinery, but I'm assuming the same basic principles apply.  Our water typically comes in the plant at pH 8-8.5.   This is problematic as it contributes to soap formation.  We dose the wash water to pH 6.5.  We are approximately 8:1 biodiesel to water.  We do not titrate the bio as this has become a rather full proof method.  An addition note is that we are using softened water which is a benefit as well as it is still pulling the metals away.

[Julian]

Welcome to the forum and wik, Kevin.

I don't know if anyone has taken into account the pH of their water ... I know I dont.  Perhaps I should check it!

Last few batches I've only had to use minimal acid as I'm gradually cutting down on the catalist I use.  I've been playing with gradual additions until I get colour and viscosity changes coupled with a temperature rise.

I guess the "No titrration method" would deliver similar results ... what processiung method do you use and what batch size?

[1958steveflying]

  I've been playing with gradual additions until I get colour and viscosity changes coupled with a temperature rise.

Hi Julian... out of interest can you elaborate the " coupled with a temperature rise."

 cheers Steve

[Julian]

It's detailed on another thread, I'll try and find it.

I assume it's the exothermic reaction taking place.

[Julian]

Here you go ... http://www.biopowered.co.uk/forum/index.php/topic,1264.0.html

Two posts towards the bottom of the page, one with a photo.

[1958steveflying]

It's detailed on another thread, I'll try and find it.

I assume it's the exothermic reaction taking place.

I took your post to mean adding the acid in small additions caused a temperature rise... my bad sorry

[nathanrobo]

Last few batches I've only had to use minimal acid as I'm gradually cutting down on the catalist I use. 

My new set process / set up has similarly allowed me to use less KOH (always seem to get either 94 or 95% conversion after stage one now) which means that neutralising is easier.  Washing is now consistently 4 x 10 litre buckets to a crystal 50/50... another benefit of getting a great first reaction :-)