As the title says, I am curious if anybody here has experimented with that ‘other’ plant agnostic source of motor fuel, an emulsion of ( finely powdered) charcoal and water.
A derivititive of coal water slurries, I find it stunning that there is virtually no material available on this type of fuel, bit apparently it is a thing, and it has been shown in research to be usable as is in commercial diesel engines, with comparable energy densities; The only apparent drawback seems to be that coal water slurries required a ‘pilot’ shot of diesel to start the motor for faster running diesels to overcome the thermal inertia of the water - but that might not necessarily be true for charcoal. And even if it was, surely a small blend of say peanut oil added to the mix remove that obstacle( as compared highly refined biodiesel as the only fuel). I would also wager that some lighter fraction of the ‘bio oil’ condensed from the out gas of a gasifier could serve the same purpose, if one is really committed to going the fully self sourced route. And while the most desirable feedstocks( i.e. switchgrass) are said to be too high in silica, that can be fairly easily settled out before final blending.
So yeah - another topic a bit outside the usual subject matter for this group - but that’s the fun, 'ey? But I honestly can’t believe there is so little activity around a fuel that seems to check all the same boxes as wood gas( at least for diesels) without any of the drawbacks. You literally mill it, mix it, and go. No heat, no chemistry, and a very compact fuel from any plant based( or even algael) feedstock available. You’d think this would be all over YouTube.
Also, thanks to everyone who commented on my earlier topic( on the steam production and compression of wood gas). I wasn’t sure if it would get much response, so the large number of comments was nice.
Joel,
I must admit, I have never heard of that. The first thing that comes into my mind is how do you get enough carbon into the fluid, yet still be able to flow it through fuel injectors, without too much water in the mix… Must be milled extremely fine, like talcum powder.
Edit: Is this like a water-based house paint?? (Emulsion / Slurry, without polymer binders?)
According to the almighty Wiki, particle size for coal water slurries is between 10 and 65 micrometers. Here’s all the dirty details( what there are of them):
I seem.to recall a similar particle range for charcoal slurries. From what I have been able to find, a ‘fixer’ to prevent settling is a nice to have, but not necessary to function.
There are a couple of research papers on charcoal based slurries around the web, but honestly I managed precisely zero sleep last night, and even after a couple of quick naps I’m too dang tired to find them at the moment, but I will find them later if desired.
I really love the simplicity of this approach. I’m not in a position to experiment, but this seems like a ton of fun to play with.
Joel,
Wikipedia article answers my base questions. Next thing is to try and re-create a slurry, add it to an already proven burner / forge kind of thing, and try to figure the added heat energy. The “flamin’ hot” picture in the Wikipedia article looks like a spiderweb of fine streams burning… Verrry Interesting!
Might be difficult for a backyard builder (like me).
Here is a video from a maker of equipment showing a favorable fuel cost budget, but ignoring all the extra electricity required for fuel preparation and handling. You be the judge. Too complicated for small scale, I believe. Nice Music, though!
I believe I read somewhere that 70 or 80 years ago that fuel for heating was delivered as a coal slurry in Europe. At the time I read it is sounded unusual as most all the coal heating systems here were all coal stokers.
Also, was it the pulverized coal or silica( which can be ore separated) that caused the wear? Perhaps other alternatives( i.e. natural gas) were easier to implement at the time than piped and treated slurry.
The bigest problem l have with this is ash. Charcoal contains at least 3% ash and there is no way around it. All that ash has to go trugh the engine. And coal is even worse at 10%. The engine isnt gonna last wery long
" I am curious if anybody has experimented with that ‘other’ plant agnostic . . . of (finely powdered) charcoal and water?"
Sure. Nepal Beehive charcoal stoves.
They take invasive weeds. Charcoal them in steel retorts. Grind up the chared stems and leaves. Add water. Make a moldable paste. Form the paste into beehive molds. Carefully remove and stack. Air/sun dry to make formed controllable heating charcoal fuel pucks.
They do not have the engine needs to gasify for engine fuel, but no reason these could not be done. The weeds silica ash settled and filtered out before the engine.
But I honestly can’t believe there is so little activity around a fuel that seems to check all the same boxes as wood gas( at least for diesels) without any of the drawbacks. You literally mill it, mix it, and go. No heat, no chemistry, and a very compact fuel from any plant based( or even algael) feedstock available. You’d think this would be all over YouTube.
Must be milled extremely fine, like talcum powder.
Nice Music, though! 
