when to wash first test batch - Diesel Forum

JCC7 · 11-13-2005, 04:22 PM

I used the Dr. Pepper technique, seems to be layering now as it's supposed to. Do I really need to wait 8-10 hours on this small batch before removing the glicerin and beginning the wash proceedure? It's been about an hour since mixing, I placed the bottle upside down to seperate, looks like about an inch or so at the bottom has seperated so far.
John
I'm in the dark, please help

JCC7 · 11-13-2005, 07:11 PM

I waited about 2 hours or so then drained the glicerin. I did several washes and all seems well except the amount of bio I was left with? I began with a liter of oil plus 250ml of methanol, and now I only have about 400ml of bio. Does this seem right? I must have drained off too much during the washes I guess. Any ideas?
John

rcdallas · 11-13-2005, 09:10 PM

They say all your glycerin should about equal the amount of methanol you added.

I've done the Dr. Pepper, the amount of methanol I added about equaled at the bottom.

JCC7 · 11-13-2005, 09:46 PM

The glycerin I drained off wasn't equal to the methanol I used, actually it was closer to half of the methanol. I only let it settle for about 2 hours but it didn't really change during the last hour? I've made a second test batch and will let it settle over night. I read somewhere the glycerin will harden below 100degrees. Made it sound like I could let it get hard then pour off the bio? Anyone tried this?
John

BobbySnider · 11-14-2005, 07:11 AM

None of the glycerin has ever hardened in any of my test batches. My pump seems to have a tendency to drip and the glycerin coming out of that will harden.

Ctek · 11-14-2005, 06:57 PM

I do 40 gallon batches of fuel with 8 gallons of methanol. Depending on the quality of the oil I get as few as 4.5 to 5 gallons of glycerine and as many as 8 or 9 gallons of glycerine from batch to batch.

I would guess that you likely drained off part of the bio diesel while washing. While washing any foam or coagulated material that is yellowish contains bio diesel. Wash water is milky to clear. Don't drain any other color of liquid other than milky or clear.

JCC7 · 11-14-2005, 07:29 PM

I let it set overnight, actually about 20 hours and drained off 170ml of glycerin. This is used oil that I strained with a coffee filter, didn't have any moisture in it either. I'm going to wash it now and try to be more careful as to not lose so much fuel. (I'm still making the 1 liter test batches) Thanks for the help. I'm looking forward to building the processor, but need to get this figured out first.
John