g.day just finished washing and drying my bio however did the m3 test found that i had .4ml of heavies at the bottom of the jar and resembled a foggy appearance.
Not to concerned of this but at a loss on how to correct this, is it because i didn't allow for the ph of the meth. Do i need to add more Koh or more meth,would like to get it right the first time. done 5 batches and the end result is always exactly the same.
Thanks coy.

I'm intrigued. Whats the m3 test. Also know way of knowing how much more or less of stuff you need and you haven't elaborated on your process.

__________________
Joe Morgan
Brisbane Biodiesel Site Admin
http://www.brisbanebiodiesel.com

Searching tips using Google - SVO Dual tank systems
SVO, Common Rail and Direct Injection - Vehicles converted to Used Cooking Oil

sorry joe it was abbreviated for methanol test 3/27 i put in 3ml of bd 27ml of methanol. in my titration i use isopropyl alcohol being as pure as i can get it is as close to neutral as possible.
i also do a Minni batch at 100ml of methanol and 500ml wvo end result is a pass on the 3/27 test foggy for 5 min but comes clear.
Though i mimic this with 100L wvo and 20L methanol and wash, dry, etc
every time same with the large batch .4 settling oil at the test why
I'm at a loss all information i have read says this should be right or have i mist something.

Thwere are a number of issues which may be causing the problem.

Water in the oil is a possibility.
You could also try to "blank" the titration ie, add some indicator to the isopropyl and a drop or 2 of the titration fluid, until the indicator changes colour and it stays changed for ~30 seconds, then add the oil and perform the titration.
Is there a difference in the recation temperature?
Do you use any acid in the wash priocess?

There will be other issues which could impact on the results, these are the first which come to my mind.

Regards,
Tony

__________________
Searching the Biofuels Forum using Google
Adding images and/or documents to your posts

Hello Coy

Another posibility is that your mixing lacks vigour. Extra mixing time might solve this problem.
Many people do the 3/27 test after the first hour of mixing and if it does not pass continue mixing. I am aware of some people who need to mix for 3 hours or more to pass.

High Guys the answer to your Questions are:
no i dont use any acid
i ensure that batch is 99.9% dry i do the hot pan test for that.
my mixing time is at 2 hours heated at 55deg cel but is not held at that i use a gas heating sourse when it is heated to temp i turn off add ingreedience.
owe when i do the methenol test i also check the ph
The 100L batch shows 6.4 the minni batch 7.2
hope this helps
thanks coy.

pH is meaningless with oil and biodiesel, unless you have a lot of water in it, in which case the acid value is the least of your problems. Is see that you have dry oil, from your HPT, so pH in your case is meaningless, except that it shows a difference between the batches, which is unlikely to mean anything, unless it is in an aqueous solution.

Have you "blanked" your titration, before adding the oil and continuing with the titration?
What are you mixing with?


If all of the above are adequate for the task, perhaps you should experiment with several mini batches adding an extra 0.5g/L KOH up to an extra 2.5 or 3 g/L, in 0.5g/L steps.
Then compare the outcomes from these tests.


Regards,
Tony

__________________
Searching the Biofuels Forum using Google
Adding images and/or documents to your posts

thanks tony i shall try what u are telling me.
however woke up this morning came accross the conclusion that my scales could be out shall get them checked first and i will post my results when i do

hey its me again got my scales checked like i said i would and much to my surprise the professional told me they were 11gr out so instead of me weighing 100gr i was getting 89gr this would explain about though will go ahead with what you suggested tony just to be sure thanks heaps

That error would be enough, when measuring KOH for a 100L batch, measuring at the 100g end would cause a significant reduction in the KOH used in the mix, whereas, the amount measured for the test batch would not be affected as badly.

The test batches will allow you to determine with accuracy, the amount of KOH needed, but if the scales are out, it will not help you meet the 3/27 test on the 100L batches.

It is usually better to be 10% over than 10% under in the KOH used in the process, if your aim is high conversion biodiesel. The downside to the higher KOH amount is reduced yield of fuel due to increased soap production.

I await your next batch test results.

Regards,
Tony

__________________
Searching the Biofuels Forum using Google
Adding images and/or documents to your posts