Wallace I agree on the CO to CO2 shift. It’s also based on visual evidence shift when it gets beat up from pressure changes and heavy sharp bends. Maybe those two are the same now that I think about it.
Doug Williams used to say cool the gas as fast as possible as much as practical to stop reversion and get the excess water out.
Want to see something that will really blow your mind?
That micro carbon dust is magnetic.
Try it!!!
I don’t understand why but its true.
With all the recent media attention to the stranger properties of Carbon nano tubes, graphene and such there are still things about carbon we do not fully understand yet.
20 years ago before I ever heard or read of such things Doug Williams made an off hand comment he found magnetic carbon in his gasifiers decades earlier.
Who knows what other chemistry might be going on in that ash pit no one has looked at yet.
Snippet from the past
Date: Fri, 27 Feb 1998 16:48:43 -0500
From: Thomas Reed [email protected]
Subject: Re: GAS-L: Re Soot in producer gasDear Doug, Claus, Tom Koch et al:
Doug implies (below) that soot originates from the reverse Boudouard
reactionCO ==> CO2 + C
This reaction is favored thermodynamically (over the reverse) below about
700C. Kinetically it is very slow, except on metal surfaces. In steel
mills the carbon plates out as “kisch” (shit) carbon and is very
slippery.
Below 500 C production is very slow.So, I am not sure that any of the soot found in producer gas comes from
this reaction. As I said before, most soot originates from pyrolysis of
hydrocarbons and other large molecules and is submicron.
snip
VTY, TOM REED
Thank very much for the interesting information. Beeing one of the danes that have not undetstood the soot formation process fully, i would ask you if you could give me (us) a few titles of the litterature you are reffering to.
Page 16 the only image I can find of this strange magnetic carbon phenomenon…
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Very very interesting. There are wrapping magnets one can get for oil filter cans, maybe someone could wrap one or two around the last run of metal pipe going to the engine, that or add some old motor magnets into their air cleaner pan. Somewhere easy to get to and vacuum up or wipe out on a weekly basis.
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Its so fine its nothing to worry about.
The carbon burns in an engine.
It might ( I am going to say most likely ) is a form a graphite, and graphite is a dry lubricant.
PURE SPECULATION HERE just pulling some random thoughts out of thin air I can not prove!!!
The ultra fine soot might have beneficial properties in lubrication and cushioning things on the compression ring side we are not aware of.
Some papers talk about well filtered gasifier fueled engines show lower cylinder wear.
This flies in the face of conventional logic because some dry gas engines on propane often need air oilers to keep the tops of the liners from wearing too fast
Woodgas has acids and things in it that should promote more wear than it would appear actually happens…
So much we still don’t understand.
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Wallace I’ve tried talking about CO revision to CO2 leaving free carbons to chains link up.
I’ve said this is the probable cause for much of the down stream of the throttle plates soots building up.
I am told by the educated chemist types that this is impossible because it would take heat energy to drive this reversion.
Flows forced past a shear edge creates turbulence energy!! Energy under micro-vacuum conditions.
Yes actual (not mineral cored soot’s), but pure free formed soot’s, will cylinder walls lubricate. Burn oxidize as a heating fuel.
I read where later University studies in New Zealand proved the magnetic carbon was due to iron minerals the trees had uptaken.
S.U.
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The iron minerals is what bugs me. Very high iron content here so I suspect I can see a lot more. I’d be afraid of that scratching my bore.
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What holds the molecular structures together The Electric Magnetic Field. This is what Tesla, Sir Oliver Heavyside, and Steinbeck all talked about it in there writings. That reading did blow my mind, very hard to understand it. I understand alittle.
All three could understand the electric magnetic resonating field and could apply it to working devices. Tesla inventions came from reading their writings and proofs on their electrical engineering theories.
All three men were genius in there time and still are.
Bob
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Bob:
Next few runs can you take some pictures of the char bed.
I am curious to see if there is any changes you can spot in how the wood is pyrolized compared to the pure dry wood runs.
Maybe there is something hidden in there…
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What Id like to see is the temp differentials from core temp to grate temps on either fuel mixture. As you mentioned the addition of the charcoal maybe freeing up energy for later process and absorbed into those processes further down stream. I would expect to see a much higher core temp and a much lower grate temp with a mixture. The higher this differential the more eficient the gasifier is processing fuel and converting it to usable gas. If I remember correctly Bob has stated the hopper had higher temps. So that is actually good and I would expect to see this. Maybe get gas exit temps after the reactor, I bet the gas will be cooler then normal.
The thing to remember here is the differential. Not just taking a reading of the gas exit temp. It could actually be higher than direct wood. But if the the core temp is also hotter it more about how much hotter and what is the differential.
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I go for a nap and there is so much stuff going on here l need sidenotes to respond 
Bob, where exactly did the heat spike? The hopper or the grate? Because lm with Matt. If done correctly, charcoal shuld increase the temp in the reaction zone but lower the grate temp.
If its the hopper that got hot, thats to be expected. The reaction temp is higher and since there is nothing to retain tge temperature down it ruses. You may remember, a few days back we talked about the importance of charcoal size in the mix. What l like to do is add just enaugh engine grade size charcoal to the wood to fill the voyds between the wood peaces. This will stop the convection flow in the hopper and retain the heat down where its needed. Yes, this will block the ability to extract moisture from the hopper but thats not a problem if you use dryer chacoal, it will deal with the exess water from wood by it self!
Bob, l can not prove it but l belive your moisture meter might not be trusted. It works with measuring conductivity and since charcoal is conductive it will give a false reading. In adition its high potasium hidroxide content wll also make it more conductive.
On char dust being magnetic. I need to look further in to this. All l know is graphite, wich is the actual building block of the charcoal structure, shuld be paramagnetic and shuld actualy be repelled by a magnet ever so slightly.
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Okay Matt I do have some temperatures for you. The hopper was running cooler then normal 148°f . Normally around 156°f but it spike fast. Like when bridge collapsing in the hopper but usually then cooling back down. But it didn’t and I was almost home so I shut the gasifier down and drove on dino fuel. It went over 380 °f for a short bit. Got home looked in side and yes it was a collapse wood/Charcoal bridge.
The grate even ran cooler. 1230°f. Normally it is at 1360°f to 1460°f or there abouts.
Like I said very noticeable richer fuel to run on. I have done this with dry Charcoal, my rocket fuel mix lots of times and it works great.
But this time it was better in my opinion. More testing will be done. After working in the orchard picking up the cherry wood, I shut the gasifier down it had less then a half of a hopper after I put more straight cherry wood in.
We need some Charcoal chemistry test done here. @KristijanL , @k_vanlooken to see if there is a difference from moisture Charcoal reactionary vs. dry Charcoal with water moisture mix reactionary and hydrogen levels of each, in 2000 to 3000°f heat range.
Again inside the Charcoal is very, very small voids and capillaries passage ways. The surface area in side a piece of Charcoal is large and amazing. When dropped into 2000 to 3000 °f one of the reactions of the heat is steam and it is trying to leave going at subsonic or supersonic speeds by the white hot charcoal. Talk about velocities of movement and this is also at very high frequencies. Things changing in nanoseconds. And then this is also happening in a vacuum that is changing -10 to -30 plus. Then it goes through a restriction opening changing its velocities if the gasifier has one. Gasification is not black and white as they say. Lots of different things going on.
Bob
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It didn’t make sense to me either. graphite is para-magnetic, and amorphous carbon is non-magnetic… but graphene is magnetic. … So I got all excited for a minute but then I ran into this:
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Bob, then it fits perfectly with the theory! Thanks for comfirming!
Bob, just one word of warning. Plese dont let the low grate temps decieve you. When grate temps go down with high power, its a sure sign there is hell in the hearth. Or what l call “Supernova”. Its when temps get so hot that reactions happen so fast, also skiping steps, that the glowzone shrinks rather thain expands. Makes good gas but we enter metal melting temps at this point. My gasifier was built to withstand this for short periods of time, yet still l got erosion on one nozzle. Not to mention glass made out if molten ash the size of golf balls…
We dont want your masterpeace to melt…
Sean, l missed the second reply of Wallace just a bit up. While re reading l see he is not talking about charcoal dust but soot! Completely different stuff. Im quite sure he is right. Soot is probably in a large part consisting of graphene and similar stuff so it shuld then be slightly magnetic.
Before you guys accuse me of wichcraft, graphene isnt new or hard to make, its hard to make in a form that wuld have any practical value.
Imagine rebar. Thats graphene. Now imagine choping it up to inch long peaces. They are both the same material but one makes wonders in reinforced concreete and the other is useless…
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With wood its pretty easy to see because with every change you make to the hearth you can see the changes in the wood as it progresses.
Such things may not apply here…
But if the char is at the centre and wood lines it all the way down to the char bed and Bob shuts the gasifier down fast enough he might be able to photo and remove material inch by inch so we can and guess at the temperatures for different loads and mixtures.
Bob:
Does your gasifier separate at the hopper from the hearth?
I know a guy that expressly built them that way so he could tinker and see inside without instrumentation ( pretty cool trick I thought )
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I used to work in a steel mill.
We reheated slabs of steel in furnaces fired with blast furnace gas, we used that gas everywhere even to warm up the building in winter.
Always there is a slick film of dirt covering everything and there was no way to avoid this.
What was it?
I never thought to ask soot dirt not matter…
But it was slippery!
I have come to think this was probably mixtures of different kinds of carbon reforming under the intense heat.
Soot in the mines is different we have had it analyzed and what we learned it there is a significant amount of metal in it fused with carbon from high engine temperatures.
We might find gasifier soot is like that too
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Yes Kristijan. Thank you for the warning. I have had my grate up to 1730 °f before I know that was really hot. But no damage to the grate. I am sure theory is correct. I definitely do not want to destroy the firetube but I did build it to take the heat with reinforced heat shielding plates. Everything is heavy duty in the firetube.
Yes it can be taken apart just above the the firetube but with great difficulty so that is not going to happen unless the hopper needs to be replace or repaired. But my Double Flute gasifier does come apart easly. More testing this is exciting to say none the less.
Bob
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He is, but then if you look at the picture, it doesn’t look like soot, it looks more like amorphous carbon, but I bet it has iron in it. It spikes like ferrofluid, and old school laser printer toner had iron oxide in it and acts that way. It might be iron oxide that formed with thermal decomposition. It might be fuel dependent as well.
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When you look at combustion in a oil burners and coal fired systems they run with about a 10% excess of oxygen to ensure everything is burned.
We are run in an oxygen deprived system to intentionally create CO.
I don’t know a lot about the science of this.
Measurable amounts of our created CO revert to carbon and CO2.
How much of our actual gas composition was CO2 after it left the reduction zone and how much of this is reversion caused?
Some carbon is even dissolving into the steel components of the gasifier itself at these temperatures.
http://www.heat-treat-doctor.com/documents/Considerations%20in%20HT1.pdf
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I did charcoal on a 3.1L V-6. I guess some people would consider that a “smaller” engine. I used a 55 gallon drum with a very, very crude intake made of firebricks. Top speed 62 mph at the charcoal gasification workshop I did at OSE back in '15. My only complaint is that the barrel rusted out too quickly from the moisture. I don’t remember what the consumption was, but a truck would need a bigger vessel for sure.
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Oh and it was an updraft. Basically a Gilmore simple fire. It worked. Not much I would improve but yes the intake was a problem. I did EGR. Still melted the firebricks. Cleaning ash wasn’t too much trouble just turn the vessel upside down and empty it.
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