Hi guys i would just like to know how important titration is. Ive been making bio diesel for about 5 years now and i have never done a titration test. I use 7g of lye per litre. My bd is, in my and a local commercial bd producers opinion, fab. Clear as lager nice and thin, gives me no probs at below zero c and i seem to be getting the right amount of glycerine from the reaction.

I have done over 60000 miles in various tdis and right now run a TDI PD on bd100 through winter and summer. However i thought i would read the bd tutorial and it mentions using 5g of lye as a base but then later on mentions the fact that home brewers use 3.5g and that commercial producers tend to use more.

Could anybody explain this as it dosent seem to make a lot of sense.

Thanks all and if im being stupid please tell me.

audiboy,

Isn't it great that biodiesel can be made so many different ways?

There are three reasons to titrate, but they probably don't apply to you.

1) Inconsistent WVO sources. While your oil sources sound to have been consistently providing good oil over the years, that is not the case for everyone. Not only does FFA content vary from restaurant to restaurant, but it can change suddenly at a restaurant as well.

2) Finding new oil sources. The easiest way to tell the FFA content of a new oil source is to titrate it. You could make a mini batch to see how well it does with a fixed recipe, but that seems like a lot of extra work to me.

3) Troubleshooting failures. Most of us have the occasional failed batch. Knowing the titration value of the oil can help one to understand why a particular batch failed.

Thanks for the reply Rick. But does this mean that i should carry on as usual or titrate. as im not sure from the info in the tutorial. There seems to be quite a difference between a base of 3.5g and 5g. Many articles i have read on the internet seem to vary with the base, some say 3.5 some 4 some 5g.

audiboy,

Do what works for you. There are no rules. Most of us on the forums recommend newbies learn how to titrate for the reasons above. No one is going to tell you, with your five years experience at making biodiesel, how you should make it differently.

Thanks Rick, you never stop learning i may have been doing it for 5 years but i just get worried sometimes that a may be making a bag of ****, but it does seem to work very well so thanks for your input.

I am brand new to bio diesel and am getting a bit overwhelmed by everything. Girl mark is coming to my town at the end of Dec and I hope this will help. It does seem like there would be a solid figure that would work with the majoirty of all oils collected. I haven't read anything about using to much lye or Koh just not enough. But like I said I am still at the overwhelmed stage!!

NCHornet,
i was in the same boat, extremely overwhelmed but after taking girlmark's bio workshop in MI this summer it all made so much sense and making biodiesel was a lotless complicated than I had lead myself to believe. i learn much easier/quicker with actual hands on workshops and clear physical/visual results. you won't be dissapointed with the workshop she puts on. good luck.

audiboy,

Your success with the modern PD with 60k is very encouraging. How long have you had your PD VW?

What Rick says is true, and I'd like to add to it other reasons why testing might be good:

1. Even though your oil comes from one source, variation is possible.

2. Knowing the inputs and outputs from your system can allow you to adjust it to your needs - ie lower cost, higher conversion, easier wash, etc.

You might consider doing 3/27 on your finished fuel. Also, titration can tell you if you are using too much, as well as too little catalyst.

In theory, "too little" catalyst will give lower conversion, and "too much" will give needlessly high soap. I put the quotes, since these are relative to whatever your standards are, not to some set figure on CBT, or anywhere else.

On the other hand, if it ain't broke, don't be in too much of a rush to fix it.