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AIR washing

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October 27, 2013, 10:00 AM
AIR washing
Hi everybody.

I don t like water washing bio anymore, because it takes to much time. Do you have any idea what is the best and save way to wash it? Is ok not to wash it but only settle it long time in garage? Is needed that settle tank is open top or sealed because of methanol vapours? What about air washing?Is OK to just use aquarium air pump to bubble unwashed bio?

October 27, 2013, 02:55 PM
Air washing evaporate methanol, and thats leads soaps fall out.
Fall out takes time, if you want all out, for long as its possible, like month.
If you want to fasten this you may dry wash
for examble with wood sawdust. Its better if its hardwood.

I make batch and dont remove glyc. Demeth bio and glyc together,beware of back reaction.
After demeth, one hour settle for glyc to drop down i drain glyc of and continue demeth bio.
Transfer to another tank to " air wash" remaining meth with aquarium pump.
After day or two i drywash through tower full of sawdust. First i
Tried shavings but they didn't work well, sawdust better.

Best regards Tatu
October 27, 2013, 04:16 PM
Which sawdust do you have? I tried with spruce sawdust but nothing happened. I also don t like sawdust because of spontaneous fire...

Any picture of your sawdust drier?
October 28, 2013, 01:21 AM
I use birch sawdust, and its very dry.
Others use mostly oak, but here where i live, its too rare.
Probably oak gives better results.

My tower is 3" wide and 78" tall, made from PP drain pipe.
Its hold about 2,5 gallons (10 L) sawdust. Iam planing to
make second pipe to improve results.
Oil is circulating via circulating pump about 6-7 gph (30L/H)
couple of hours.

I take few pictures after work and try to upload here.
Its crude looking but they work.

Tower is full of oil allways so i dont worry about fire.
October 28, 2013, 11:01 AM
Here's the picture of settling tank, circulating pump and lower part of dry wash tower. First i was pumping to downstream, but lately i changed it go to upstream. Clean bio games out of the top, through filter. Simple as that.

Tower is in temporary support now, as you can see. This is still experiment version but soon i make second tower and final support for that.
This is easy way to clean up bio. Just leave pump on for few hours and that's it.

In tower, what i have research, must by sawdust, Shavings don't work. Sawdust is made like across the wood grain, therefore grain is still open to impurity, like soap. Shavings don't have this feature.
This is my opinion, correct if i am wrong.

Hope this helped.

October 28, 2013, 05:50 PM
Legal Eagle
If what you are interested in is air washing only then I suggest you read up on Graham Laming's site.
He has been using this type of system for some time now with good success. No water. No chips and/or resin.

** Biodiesel Glycerine Soap - The Guide
- on 5 continents helping people make & sell soap from the Biodiesel Glycerine.

January 19, 2014, 11:48 AM
is safe to fill pvc like on this link full of sawdust or it s too small for filtering 100 l batch??