Anyone that makes or uses biodiesel have any thoughts on the goop that settles out of it sometimes? In this case its made with the right amounts of reactants, temperature and washed right, but its still settling out crud after a few weeks. Im draining the filter and seeing soapy stuff. Maybe water settling out?
I heat the stuff and let it dry before use but maybe thats not doing the trick.

 

If the temperature is warm and its not high freeze point esters settling out, then its an indication of poor reaction.

Did you do a 3/27 test to determine reaction quality?

 

Huh.. not yet but Ill try that. bet it comes back foggy and weird looking.
If its an incomplete reaction, what amounts of methanol and lye should I use for 30 gal of oil?

 

What lye are you using?

 

99% lye from some ebay guy. Not red devil or anything recognizable.
I might try running more reactants than necessary next time to see if the lye is weak or my measurement of oil volume is off. That 3/27 test sounds like the trick.

 

As far as how much lye you use for your batch is determined by your titration. Ours typically for 40 gallons using peanut oil is titrating at 1.2'ish.

As far as the soapy stuff, I would say that it isn't fully reacted or you didn't get all the glycerin out of it before washing. We've had batches that looked good, but to do the 3/27 test we'd have particulates and some oil globs that would appear. So don't be too suprised if thats what you see when you do your test.

Also, I'm not sure if your worried about this or not, but when your drying don't put the biodiesel out in the direct sunlight. That I guess starts to degrade the biodiesel and your oxidation will be high.

Good luck and keep us posted !!!

 

also, check your titrant to see if it is bad. use 1ml of new oil 10ml of meth and add titrant. the max reading schould be no more then .5 if it is, the titrant is bad.

 

I think its suggested to make new stuff once a month. We usually make ours fresh every week just to be on the safe side.

 

Looks like I need a new gram scale, urgh.
This latest batch I added a bit more methoxide to see what happens. So far it looks pretty clear.
When you dry your bio what do you do? All Im doing is recirculating heated fuel in a barrel for a few hours spraying it against the inside of the barrel.

 

I rarely get any "Goop" settling out, occasionally if I didn't let it settle long enough after the wash I'll get a little water at the bottom, but I just pour off everything else and don't worry about it. Do you use a single stage mix or 2 stage? My 2 stage is good enough to pass ASTM standards according to Buffalo Biodiesel Inc.

 

How big are your batches? I could recommend a scale. I've used the spray drying method two times now with very surprising and pleasing results. The one reason I didn't really want to use that method is because it is exposed to a lot of oxygen and that's how oil polymerizes. It hasn't seemed to be a problem with my oil/fuel though. You said it takes a few hours? I bought a $5 fan from Wal-Mart and mounted to the top of the tank and with a fan running I dry about 20 gallons in and hour. It looks clear before the hour, but I run it longer. I have kind of a rectangular opening on the top of a 60 gallon HDPE barrel and the fan covers about half the opening and blows in.

 

Well I -was- going to try some testing on this latest batch, but I think I must have left the drain valve open on the washtank because it was dead empty this morning. Im so very not happy.. Argh!
Im working on some more oil sources since I dont have enough at the moment.

 

All your biodiesel leaked out? Where did it go? It didn't make a mess?

 

Not really, all the methanol was gone at that point and it was fairly clean. It went out the drain into the lawn. Im just mad because I could swear I checked that valve 3x after draining the water on the bottom. =(
On the plus side I scored 125gal of clean oil over the weekend. it titrates at 1.5 and when I process it, it looks light in color.
The thing thats bugging me is that when I wash it, it seems to take longer for the water to settle out and Im worrying about remaining glycerin, etc. it has a 'chicken soup' kind of look to it.
I have a batch right now in the heat tank to dry.. Ill give that fan idea a shot. Ive been spraying it with the pump on the reactor so it circulates well. once its dry Im going to try the 27/3 test and see what it does.
If any water or extra glycerin is there it shouldnt dissolve cleanly, right?

I need to get some new mister nozzles since my brass ones keep clogging and the plastic ones I got are too strong and form an emulsion easily on the first wash.

 

Argh.. so my latest batch I washed and heated overnight in another barrel to dry it. When I went to pump it, it immediately clogged my water-block filter and I could see soapy residue inside.
I can only assume either the methanol and lye arent fully mixed or my titration is off.
Its back in the processor with 3gal methanol + 200g lye to see what it does.