Bob, I can’t entirely tell if it’s just perspective or if you want the flute nozzle to be diagonal in the barrel? I would have assumed it being laid flat to ensure a plane of fire and prevent dirty gasses from getting to the grate.
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All the nozzles are 11" from the bottem of the heat sink. The soot/ash and clinkers will fall downwards this is a reverse grate no big pieces will be able to get to the filter hot screen it is a seprate container in side the barrel that can be removed for cleaning. Even the heat sink is hanging by 2 chains. When gases are in a vaccum under suction they head to the least path of resistance that will be under or around the bottom part of the plate then up to the grate. The gases are heading for the exit point that is at the grate. There will be no charcoal packing on the grate. Well that’s the plan.
Bob
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I was out today doing a tar/water and soot/water clean out on the tanks in the wood burner truck WK Gasifier. It is winter now and getting cold at nights. I just thought of something with Charcoal gasifiers you do not have to do this, no tar/water and soot/water clean outs. No slushing the tanks out. The hayfilter water flush out yes but thats about it if you use a hayfilter. Ash clean outs you have to do that on both types of gasifiers. No tar messes to deal with this is nice, a big plus on charcoal gasifiers. I think I will go and make some more charcoal tomorrow you can never have to much charcoal on hand. The same with wood chunks.
Bob
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In the short times I’ve used the diagonal draft, I’ve found you do get quite a bit of water. But it’s just sooty water no tar. I think for a local runabout a charcoal gasifier would be nice. Something to utilize the wood chunker tailings that you dont want to risk your fingers over.
I always looked like a ragamuffin after dealing with the Mazda’s gasifier. Had to keep wet wipes in the truck to clean my face and hands.
I dread to think what a V8’s charcoal consumption would be.
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I would figure twice as much wood once it was made into charcoal and with water mist injection at the nozzle or nozzles. More Hydrogen being produce in the final product of gases being made.
The beauty of it is this you can run any old V-8 engine with a 4 barrel or two or one barrel carb. No messing with computers and the electronics. With a mix plate for the chargas and air under the carb and some linkage to a butter fly valve to open before the gas carb opens. Run it on hybred if needed.
Bob
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Here is a thought on this subject that might not have been talked about much lately. In the very cold winter months driving on a wood gasifier.
It is possible that on gasoline will increase in the winter months to help get the gasifier up and going. We do not want to make tar, and a cold firetube in the reaction zoon will do this on the raw wood gasifier. How to avoid this it needs this warming up the gasifier before using it in winter.
Now on my truck I can run on gasoline to preheat the air. And let my suction blower work a little longer heating the firetube up. Now the winter months might be a lot different where you live. I am talking about minus freezing weather for days at a time.
With a charcoal unit there is no problem of making tar. So why not get your raw wood gasifier up to running heat with a little help with lump charcoal on starting up the wood gasifier.
Now I like making my rocket fuel mix, this has a little charcoal mixed in with my raw wood.
So try this instead at starting up with this added. Cold start up open the hopper and hopefully it is burn down to just above the nozzles when you shut it down. Do this in the winter cold months at shut down even if you have to drive the vehicle around a little longer. Oh no not that! Hee, hee, just drive it until you see the hopper temp rising. Then shut it down.
The next day open up the hopper and clear area above the nozzles, the brands and partly pyrolyzied wood, then add larger pieces of lunp charcoal size about 12" ring about 12" or 30.4 cm high pile then light it up. Talk about a fast light up and heat in the fire tube now. Cover the area about with the hopper wood that you pulled away, and add the fresh dry wood on top. You now have a charcoal gasifier working for about 5 to 10 minuites. Then it will go back to a raw wood gasifier converting by pyroiyztion of the wood in the hopper. This can save you gasoline as well. Get the gasifier firetube good and hot. You will just have a hazy smoke coming out showing good gases like a charcoal gasifier. Start up the viehicle engine and go. No gasoline at all.
This added step is a little different then a complete cold start on a wood gasifier. It only takes a minute or to longer but it will get the gasifier up to running temps faster then the other method. I have tested it both ways on my WK Gasifier with no gas start ups and driveing off on wood gases no gasoline at all. Because I have to go up a hill a little help with gasoline on the very steep 8% grade out of my place to where it is flat ground road. But if it was flat no need for gasoline at all.
So saving our bigger charcoal pieces on ash dumps screening the popcorn and larger sizes and like the fire place coals when heating or just outside fires is handy in this very cold winter months when DOW. This is a part of fuel prepration I do too.
One more part of the other 75% of learning to Drive On Wood when operating a gasifier in the below freezing winter months in the seasonal Northern and Southern cold parts of the earth we live on. By the way @mggibb Mike was the first one to show me this little trick on getting a quick startup on a wood gasifier. It is a great idea and can be used any time cold or hot weather for a no gasoline quick startup DOW.
Bobv
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I like that idea, a little booster like spraying some ether down the gullet.
I think using a suped up snail blower would also really help get up to temps quickly. Harder draw and all that.
When do you find the gasifier good and warmed up, when the crossover is registering temp or when the cooling rail tree starts registering temps?
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My Kirby vaccum cleaner can suck a very high volume of gases though it when on high.
I like to see about 800 °f to 900 °f at the grate. And coming out the drop box to the rails about 200 °f to 275 °f if it is really cold I use the higher temps. This just takes minutes in what I call the charcoal mode of operation.
Bob
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I have yet to find any Kirby vacuums around here. Might just have to get an ametek blower. Snail blower for pulling and bilge blowers for reverse and push sounds like a good plan.
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I haven’t curb shopped a kirby but I have a few other brands. I was looking for a cheap source of copper wire for the kids to practice making jewelry, but they use aluminum for the coil windings in some of them and the kids gave up on jewelry.However of the 3 i picked up all of them worked.
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Kirby: Haven’t seen one for awhile , but look in second-hand stores, resale shops, Salvation Army / Goodwill / St. Vincent De Paul thrift stores. Maybe now FB Marketplace, but that can be a den of thieves. 
Of course the Ametek is a good investment, probably!
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I found mine at the recycle metal scrap yard. The only thing wrong with it was their fancy lock out safety on/off switch for the atachments removed it. I bypassed safety lock out and put on a push buttom on/off turn dimmer switch. As good as new with speed control.
Bob
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Great thread, but I don’t think Charcoal and Wood gasification should be thought of as a conflict or debate, as each has it’s benefits and costs and appropriate use.
Comparing gasifiers alone is fairly meaningless. To think clearly about them, a valid comparison needs to be ‘end to end’, comparing and contrasting the whole system.
**fuel sourcing, processing, and storage
**gasifier size, complexity, cost, and build labor
**operating labor and complexity
**the risks and your relevant skill set
**perhaps just your preferred balance of variables
In reality, all gasifiers are charcoal gasifiers, so the question is really “make charcoal inside the gasifier or separately?”.
Raw wood gasifiers:
When you opt for raw wood, (making the charcoal in the gasifier) you have to manage the moisture and tars that are present with wood pyrolysis or they will overwhelm the gasifier.
Some ways this is done are;
-You can stipulate bone dry wood with critical dimensions(Imbert).
-You can condense and trap the steam and tars (monorator, WK).
-You can use very small fuel volumes to limit them (drizzler, joni).
-You can eject the moisture and tars (joni, N Korean military, anyone who runs a long startup/warmup).
-You can accept tarry gas and focus on extensive cleanup infrastructure (updrafts).
Regardless of method, you learn to monitor, interpret, and manage temperatures and pressures for filters, grates, and reservoirs. This is the 75% of gasification referenced often.
**wood is found almost everywhere
**processing raw wood is cleaner and easier than making charcoal
**wood processing doesn’t make smoke pollution like charcoal usually does
**wood gas has more energy than charcoal gas
**wood has twice the energy density of charcoal by volume
Charcoal gasification:
When you opt for charcoal gasification, you move the moisture and tar management to another place in the system (charcoal making).
Because of this;
**charcoal gasifiers are simpler and cheaper
**they start up more quickly and are generally more reliable
**they weigh less, put less burden on the operator, and dramatically reduce the chances of tar in your engine
**Explosive events seldom happen and are less energetic when they do
**Charcoal flows better so bridging seldom happens
**The gas cleanup is much easier
**Charcoal has twice the energy of wood by weight
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BUT;
Charcoal making is usually a lot more dirty and difficult than raw wood processing.
Around 60% of the energy used in making charcoal is usually wasted.
Larger engines consume a lot of fuel and wood has a naturally high energy density by volume.
BUT;
Making raw wood chunks or chips is also a high labor and/or power process.
Wood gasifiers also waste some of the available energy of wood through various inefficiencies, longer startup, and energy trapped in the tar and slipped charcoal.
Fire can take the place of chippers, chunkers, or grinders as it reduces wood to charcoal, which is then naturally dry and weak and easier to process than wood.
Charcoal can be made from biomass that isn’t suitable for wood gasifiers, making charcoal fuel more available overall.
But;
Wood gasifiers can use ‘found’ fuel, without the need for the charring step.
Raw wood is usually unaffected by fire danger, which might hinder charcoal operations.
Wood processing can often use off-the-shelf tools without having to DIY, as is usually necessary with charcoal.
Large engines with large gas flows produce enough internal gasifier heat that tar free gas is relatively easy to achieve.
But;
‘No visible smoke’ charcoal making is possible, though not common.
If you capture the energy used in making charcoal, charcoal gasification becomes very attractive.
The messy job of maintaining filters, dumping tar, cleaning manifolds, and handling condensate on a wood gasifier is similar to the mess of making charcoal, but isn’t part of your vehicle.
If you are using a small engine (below 1L), the heat balance issue pretty much dictates using a charcoal gasifier.
SO, ‘To each their own’;
Biomass to shaft power is complicated and difficult, but you get some choice as to where and how you prefer to manage that complexity.
The fuel sourcing and processing part of gasification ends up being the most important.
The importance of each variable will be different for each person within their unique situation, and I wouldn’t assume to know what balance of variables is best for someone else.
Use the most appropriate tool for your circumstances. Use both…
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Nice write up Chuck, let me tell you some numbers about the preparation of wood chips. Yesterday I cut branches with a screw cutter, it needs approx. 20 hp for propulsion, which is provided by my tractor, which runs 90% on wood and 10% on diesel fuel. In one hour, it cuts 2-3 cubic meters of wood chips, this represents approx. 1000 kg of dry wood chips, the tractor uses less than 10 kg of wood (6-7 kg) and less than 1 liter of diesel fuel for this work, so I can say that the preparation of wood chips represents 1% of the energy that we get in the form of wood (I didn’t take my work into account, because it’s fun and fitness for me) 
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Good synopsis Chuck. For me the main point is the energy lost in charcoal production. I have batted it around some. obviously, if you are making charcoal and your system is well built then you are not making much if any smoke so you are burning the impurities out of the wood, volatiles and moisture, but how much CO is lost in the process. That’s the rub. If I wanted to get serious about it, I would build a retort wrapped in tubing or water jacketed and capture that waste heat for water heating. Actually I have built that, just not put it into use yet due to some problems with the concrete water storage tank that won’t get resolved until spring. I have some years with a Rocket Mass Heater that proves pretty much all the combustion heat is recoverable but it’s the farthest thing from a charcoal maker. Personally, I believe that any way a person can provide their own useable fuel, weather wood, charcoal, or some liquid form is just hunky dory. The vast majority of us are still slaves. Drive on Wood is the emancipation Proclamation.
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Many of you guys from the US say you can get free wood chips. Here, they go for about 30€/m3. Ofcorse its a good deal for you and no good for us.
Many of you guys in the US can get loads of pallets for free. Here, they cost l belive around 12€ a peace. Used. Again, difference.
If you got a tractor and a efficient chiper like Tone mentioned, and loads of young growth to clear, wasting time and energy on making charcoal makes litle sence.
I too have a lot of young growth to clear and l too gave a tractor and culd run a chiper, but l turn my wood in to charcoal for sale and l got loads of charcoal to small for sae but perfect for a gasifier. Guess whats my best choice…
Mr Wayne has a sawmill. Loads of offcuts that chunk real nice and cheap. He probably wount make charcoal or tear up pallets for his gasifier…
Mr Steve U lives surrounded with conifers. Making engine grade charcoal out of that will end with a huge amount of dust and is a whole nother can of worms.
JO throwing long narrow saplings in his rebak seems like with each move he makes a hopper full of perfect size wood. No point turning those nice long straight saplings to charcoal.
Someone may have a lot of standing dry knoty hard woods. Good luck chunking or chiping that. But it can be turned down to charcoal efficiantly with litle effort.
List goes on. What l want to point out is that first and most important thing to look at when deciding on what kind of a gasifier to build is what reliable sorce of fuel you have. Everything else comes acter that.
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Very well put. The means must support the needs.
While in my own case, I might get free pallets and scraps to take home for now, I don’t anticipate that to last forever so I am working towards my coppicing project to set myself up for success. I find processing small trees a lot easier than taking apart pallets or meticulously removing nails and screws.
I might add the free wood chips most in the US can get are very poor quality. It would take forever to sift through to get maybe 1/4 of the truckload as usable fuel. Better off as garden mulch to build soil or kill weeds. Tree service chips are mostly leaves and twigs chewed into dust with a few big pieces from limbs.
I wish Remet CNC had a trustworthy North American dealer.
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Very well put Kristijan.
Garry C
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On chip quality. Up untill about a month ago l wuld totaly agree. But l have since visited Tone and the fuel he uses. Long peaces, dust, sawdust… and yet his sistem is clean of tar and his resaults speak for their selfs. He is doing something right, if l wuld throw that stuff in any of my wood burners l had l wuldnt drive even a mile…
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