Ok, I've been here a while, though I'm not active much here.

I've been making BD for about 5 years now. Same oil source, same process. For the last 3 years, I've been using the same processor as well.

Problem: the last batch (current) won't dry to clear. It's like it's almost clear and dry, but not all the way. You can see through it in a jar, but it's hazy. Always before, dry has been bright sparkely clear as a bell.

Specs: 100 gallon batch. converted to liters for measurment through Biodiesel o matic spreadsheet
Oil from oriental resteraunt

Titration of oil: 1.3
Using NaOH, base of 5 plus titration
Methanol, 100% pure, using 22 gallons
water prewash after 3 hour process 6 gallons

Got good process, added prewash and let run for 30 minutes.
Got good seperation starting almost immediatly, withing 1 min.
Next day had full seperation, looked like all the other batches over the years.
Drained Glyc. and started washing

Wash with water from hose, city water. Used garden 'gentle rain' head to trickle water through. after 30 min of sitting, drained water and washed again.

second wash ran pump and used sprayer to apply water to the BD at the spray head (Fire sprinkler used for drying). Added 1 pound of salt to ensure no emulsion
Settled for 1 hour and drained water

3rd wash, used gentle rain head to trickle water over bd again, like first wash. after 30 min. drained water and turned heating elements back on to heat BD

After heating, turned on pump and used spray head to expose to air for drying.

At that point, it looked like orange juice, like always. Later that night it was about to the point it is now. That was 2 days ago. I've had it hot and spraying all day with no change.

I am wondering about under reaction somehow.

I am doing a 3/27 test in just a few minutes to see what happens.

I'm open to other ideas.

Scott

forgot to add, i did the 'shake 'em up ' test. equal amounts of bd and water, shake and let settle. water was clean.

Is it really humid while trying to dry? Living where I do I don't have to deal with wet air but have got to wonder if that affects drying. I guess I would suggest blowing air on the spraying fuel.

Forgot the little bit. I'm also using a fan to blow over the top of the processor while it's drying.


And the results of the 3/27 FAIL

So, I have underreacted BD.

Now, what to do?

Depending on what motor you use it in I guess reprocessing is in order. Do you do a 3/27 before you stop processing?

UPDATE:

I reprocessed and looks good now. A couple of notes though:

This batch is 100 gallons, so I reprocessed with 5 gallons of methanol, and 378g of NaOH. As always, I drained a sample of the batch just as I turned off the pump into a mason jar. That way I can see what is happening in the processor.

I took the jar inside, and in a couple of hours I noticed it looked funny. There was separation, but it looked like BD on top and clear water on bottom. The BD looked weird, so I touched it and it was turning to jelly!

I quickly ran to the shop and found that the reactor was still warm, so I turned the heaters on to bet it hot again, and turned the pump on to keep it from congealing. After it was hot, I turned the pump off and immediately did my first wash by using the gentle rain over the BD. I got a lot of white water, it was very heavy with NaOH and soap. I washed this batch 5 times after reprocessing, just to be sure.

It's drying again now, and seems to be looking good. Only 2 hours spray drying and it is almost done.

Mr Fixit

You must have had a bit of water still in it when you reprocessed it which cause it turn start making alot of soap. That's usually why it's a better idea to test for a complete reaction and reprocess if needed before any washing.