Another cellulostic material with some positive dehydration properties (have not measured effects on soap) came up in a discussion about drying methanol post acid stage recovery.
The use of corn grits for dehydration is evidently common in the ethanol industry.

I tried mixing grits with washed wet bio, and had promising initial results.
See this thread:
http://biodiesel.infopop.cc/eve/forums/a/tpc/f/71960555...481026212#2481026212

Of course the grits, while dehydrating, do not seem like a good way to remove methanol, so the residual methanol may keep soaps in solution making the grits less than effective on soaps.
But who knows! Could be worth a try.

Also...to find out if the acids/tannins in the woodchips ARE neutralizing soaps...couldn't we just measure FFA levels in the bio before/after woodchip treatment. FFA levels should increase if soap is being neutralized , correct?

I ran another sample using red oak that I chipped up with a chain saw. Screened it to remove as much dust as possible and then washed twice with methanol. The first wash was very dark. The second was not clear but I decided good enough for the test. After drying I put the chips in a beaker with about 200 ml of bd for 15 minutes. Filtered thereafter through a coffee filter. The bd was crystal clear. Shakem-up test looked good, without the heavy white glop seen with the cypress mulch. I later did a real soap test and it came in well under 100 ppm.

There were some delays during all these steps so the results should be discounted somewhat. But I wanted to share what I've seen in hopes others will as well.

When I get some mod's done to my processor I'll run some additional tests.

Hugh

Re meth wash of Oak. Three washes with equal amounts is where diminishing returns usually sets in. First wash takes the most. Second most of what is left. Third Most of what is still left and what is left after that is negligable. Just a rule of thumb with solvents and solutes. With a given amount of solvent you will get more solute out as three seperate equal washes.

Sounds like you are getting good results though. Look forward to hearing more.

any progress here at all?

I was reading that Tyloses formation is different for red oak than other oaks. This may be a factor in making red oak better for soap removal than other oaks.

Any chance a moderator can delete this spam?

Ant, didn't you see the ads on top of the web page? This is a sponsor. This is what we should consider a commercial break

But with a minimal required bed height of 60cm and an expansion of 2,5*volume these tubes look quite short to me. A ion exchange tube for dry resins should at least be 2m high.

In this case even magnesol would be a better choice.

Ahhh. Dunno though. Seen resin columns used successfully that are only three feetish long.

If the resin is the wet type or the biodiesel doesn't have any methanol, water or glycerol in it and the resin doesn't increase in volume, no problem.

This was amberlite and filled to the right level to allow for expansion. Settling done first to remove bulk glycerol and soap. Demethed prior to that. No water wash. Fairly standard methodology in this neck of the woods. The guy eventually switched to using two resin towers one after another for a small but definite increase in polishing over one tower.

Has anyone tried acid number testing before and after a hardwood treatment?

I wonder if some of the soap is just being split by the acidic nature of the wood.

Simply titrating the fuel before and after should tell us.

Thanks,

--- David

I haven't tried it, but it seems like a valid test.

Thanks to all who contributed to this subject as it's saved me loads of hundreds. Bought a 100l pressure tower[S/Steel] from a Blood Transfusion Service auction for 30 quid. Tore up about 20 egg cartons and dropped into bottom. Filled to about 3/4s with green oak planer shavings [left over from filing cabinet fish smoking project]added about 5 layers of geodesic fleece [non degradable stuff I use on flat roofs]to filter the dust out and topped with Scottish Pebbles to weigh it all down. Have tried it out for polishing up my biodiesel after water washing and drying, then staight into oak filter through gravity supply, followed by 1 micron filter. Works brilliantly, crystal clear. 400l so far. An added advantage for me is that all this is performed in my back garden and the stainless tank stamped Human Plasma keeps prying neighbours on their toes [although previous years of pruning with a chain saw has worked well up to now]. Cheers.

Good work Dodge!

How much is a quid? I'll take a whole pile of those SS towers if you can ship them over here for a reasonable fee


If you can, try titrating the fuel after filtering.

Titrating before won't tell us much of anything as it'll be full of soap.

This could be a funny case where you get both an acid and a base titration. The acid titration (soap test) would be valid for the bits of soap remaining, and the base titration would show any FFAs caused by acid in the wood splitting soap.

Thanks!

--- David

Quid is slang for the English pound.
Have any of you guys done any soap titrations?
In my experience crystal clear can still be over 1000ppm soap.

Quid...in my situation...is for one Scottish Pound so 30 will be approx 46 bucks.
This will cause some unrest in the ranks but I've never titrated in my life and don't have the urge now. Started off with Alex Kachs Foolproof method and now add 20% Methanol and 10g/litre KOH instead. Probably could save on the KOH by titrating as the used oil I get is hardly used but I'd rather save the time. I paddle wash the end result 4 times so would assume all soaps to be gone before sending it through the wood chips. [The paddle also came from Blood Transfusion Service and would pull me into the barrel if I used the drill at more than half speed. It would make a great outboard motor]. The shaking test leaves a thin white seperating layer [before going through wood chips] which I'm told is a good indicator. I did have a couple of drums of "mayonaise" on my early attempts at biodiesel having had problems with immersion thermostat and pump continually losing prime, but since sorting these the reaction works as it should. Pharmaceutical companies are also a good bet for S/S equipment if you can find an auction in your neck of the woods [there's a Pfizer research facility in Groton, Mass who you could ask].

With all the new people looking at wood as a filtering medium, I thought maybe this thread deserved a bump.

Though I do have access to tropical hardwood shavings from a neighbor, I can get lots more peanut shells and truckloads of dry corncobs and for that matter dry corn husks. Has anyone tried these or have some thoughts why these would or wouldn't work. My only expenses for these materials are to haul them home.

I don't think anyone here has tried that. Try it out and report back. I think it would be better if the shells or cobs are dried first.