[Gasification] Pellet Fluffing and axial/rotary screw

[Paul Francesco]

I did some research awhile back to try to make peller fuel from low MC 
wood waste (moulder shavings) and found lack of lignins for binding to 
be prohibitive (kiln dried wood) so the project was abandon due to ROI 
when wax binders had to be purchased, etc.  However, could a small 
extruder (orginially for plastics) be used to form pellets if one where 
to add waste glycerine (un-refined) from BioDiesel byproduct as a binder 
to control both acid and fluffing? The extruder (screw type- 15hp) in 
it's current configuration already works as an oil press so that over 
introduction of glycerine would not seem to be a problem.

drew wrote:

>I have used pellets in my tlud variant and found the swelling action to 
>be extremely challengingly.   So much so that I gave up on pellets 
>unless mixed with other fuel.   They seem to swell in reaction to heat, 
>but perhaps more to the resultant steam?   My system was a pressurized 
>low volume flow and it resulted some times in a hopper so packed that a 
>chisel was necessary to clear it.   The pellets I used were Fir sawdust 
>with low moisture content (< 10%).  
>
>I was not aware of the dual motion in the injection molding machines 
>makes great sense to me.  Perhaps John F.   JBF biofuels uses them in 
>his system, if not they might be worth while?
>
>All the best
>Drew
>
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