Joni I have been reading this thread for a while. I am having a hard time understanding how your nozzles/ reaction zone works. Any chance you could explain that to me a little more?
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Hi Joni, I just want to say your progressions of gasifers is great. Your cutting the old unit in half and showing how it was built was fantastic. You have inspired me and have convinced me. That I was going end up with a to heavy gasifer again to put on the back of my Subrau Outback. Others did too. “The 3 Barrel Design” . You have found something new in the world of gasification and it shows in your building of your gasifers they are very light weight and do the same or more power gas out put than the heavier weight gasifer of the pass and present. Good job on figuring this out. You are a Master Gasifer builder, it shows in your gasifer design work.
Keep it up on improving the gasifer.
I appreciate what you have done.
I apologize for getting of topic. Back to your gasifer.
Bob
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Jakob,
everything is extremely simple, your systems work according to the principle: we burn carbon - we get CO2 - we restore CO2 - we get CO and the reaction of water gas … In fact, these are erroneous opinions. My system works bypassing the phase of carbon oxidation in CO2, since the combustion process of carbon goes through two stages - first it burns to CO and in the second phase to CO2. Both reactions take place with different heat release, and the first is much faster than the second. If you have time to take the gas after the first phase, then the second phase does not occur, as for the reactions with water vapor, they take place separately and according to your statements and with the same results. With the organization of such a passage of fuel carbon oxidation reactions, there is a big difference in the composition of the gas, namely the ratio of CO and CO2. Regarding the hydrogen content, it remains at the level of an ordinary wood-fired gas generator, but CO reaches the level of a charcoal gas generator … If you are interested, I can share a book, everything is set out there from a scientific point of view, it is in Russian, but if you have time then using a translator, you can study it.
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From KristijanL on BobMacs the Double Flute Gasifier topic In the near past:
“Bob, just one more thing on CO and H2 production and restriction. I was given a chemist book as a gift from the WWII era. It is old but inorganic chemistry was well known at the time. It says carbon (charcoal) burns (oxidizes) to form CO2. We all know that. But once you cross a certain temperature barrier it starts skipping a step and burns straight C + O2 → CO. What this means is if run any gasifer at a high enough temperature it will not have that classic oxidization zone->reduction zone transition. It just becomes one reduction zone the size of the oxidization zone.
Hope this makes sense.”
And this is me saying: transition steps can be brought down with negative or positive pressures. Or catalysts factors. Some occurring naturally in certain wood species.
S.U.
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Yes Steve, I think this is what’s happing in Joni’s gasifer. We all know there is different zones of heat. Like you have said hot, Hot, HOT, AND HOTTER. We also know everything in the gasifer is time related as it functions in gasification. It might be seconds to nanoseconds in the firetube or what I like to call it the reactor because everything is operating to the laws of physics that we know of in gasification. All of Joni’s gasifers 8.0, 9.0, and 10.0 have what I need to run my Subrau on wood, and not charcoal. Wood I can go anywhere find wood prosses it and keep going. Charcoal you are limited on range and that is the simple truth.
Bob
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Hi Steve, also go back and look at the cut in half gasifer that Joni provided us to look at. I have snap shot the photo and zoomed in on it. His welds are holding on the part that I can see and he said the gasifer was still operating when he replaced it. If you look closely and study the heat patterns on the metal you can tell this was one very hot area. The bottom of the gasifer barrel has insulation 2 cm according to the diagram with a loose plate on top no welding there. The side of the barrel has
2 cm insulation and a inside shielding around it. This has no welding that I can see attached to the rest of the gasifer. It just fits around the outside of the bottom of the firetube preheater on one side and the bottom of the hopper gas out side. This allows this super hot area the expand and contract with out causeing cracking on the important welded joints. Behind this is more insulation going all the way up to the tar gutter. This stops heat from transferring up into the hopper or bunker area. At this much cooler area is where it is welded to make a complete seal for the gasifer unit. The Gasifier firetube is hanging from the weld tar gutter and can now expland and contract millimeters up and down in and out freely. The reduction plate sits in a grove at the bottom of the fire tube and seals up with ash like most other gasifers, and adjustments can be made here if need.
Now how the hopper or bunker makes the transition in the nozzles area not really sure may be cut the metal and bend shape it and weld it back up. I know I could do it this way and put nozzles in and build the heat cowling around it weld it up. With the way it is done it can expand and contract also.
But with this new method putting a nozzles pipe ring in, this is much easier to install and will receive more heat on all sides, which is very good. I could still make the smooth hopper barrel to fire tube transition with nozzles coming out this would create the hot gases under it, that Max Gasman talks about.
My conclusion is this if metals can expand and contract freely they will not crack as easily. And I am pretty sure I see this in Joni’s build. I like trying to figure things out. I have spent about 5 hours studying this if I am wrong oh well no harm done. It is fun and I like a challenge and a mystery.
Bob
Edit: Hi Joni this is also linked over on my Barrel in a Barrel in a Barrel thread. It was supposed to go there. Thanks for all the help on this I appreciate it very much.
Bob
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Hi Joni,
I am glad you are talking with young Jakob North.
He has as one of his projects a stainless steel gasifier.
Ha! I get Hate for saying this but only SS metal woodgas system will be useable past . . . say, 5 years living out in the year around seasonal weather. Upper system carbon steel eating acid. Lower system carbon steel alkaline ash eating. Activated by interval air humidity sweating when sat idle, not heated.
Regards
Steve Unruh
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It is true Stainless steel will out last carbon steel. The 2012 hopper and outside barrel and internal gasifer parts are holding up on my truck, but the hopper is getting close to the time of replacing. Hayfilter, dropbox, cooling rails and trees have all been replaced.
Bob
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I am a fan of small but massive walled mild steel systems welded together all the way. Other option is Jonis, super thin and flexible SS. To me there is no middle way.
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The weld pictured was MIG, although i have welded with TIG but not much and unfortunately don’t have pictures, it may look like TIG and that also may look like SS but it is just cold rolled mild steel instead of hot rolled steel with a mill scale finish and the bead look is from manipulation that I have practiced for a little while.
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The important thing to remember Tyler is once you learn a skill no one can take it away from you. So learn as many as you can. 
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Thank you for the good advice, and I sure will.
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Not a criticism and those are fine looking welds Tyler but I think the only reason one would have to manipulate their puddle enough to get that stacked dime look is because their heat is not set right. At least for me I want that puddle to just move forward on it own sort of like a lava flow. You may not do stick welding but if you were running a 7018 rod at the optimum heat there would be an almost flat surface on the weld and the flux would curl up and remove itself. Even with MiG I am trying to get that same smoothness. One thing that is interesting is to have someone preheat the area you are welding into with a torch to a dull red color. Your weld will just about disappear.
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I understand what you are getting at, although the instructor demonstrated the same looking weld that’s puddle behaves the same as I performed, I can definitely see the use of a stringer bead strictly for strength, but the amount of penetration from the bead I presented and a similar stringer bead is relatively the same, and from a structural aspect both could be used consistently without problems.
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Every professional welder I ever talked to pointed to that ‘stacked coin’ look as goodness.
Rindert
I should not have railroaded this thread to be about welding. Sorry.
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Back onto topic.
Here is one of Joni’s systems, front-of-vehicle mounted.
Obviously that vehicle would have to have the under clearance to accept his cooler tube rack.
And I have wood-condition using the gas-cooling heat energy for a use. Many times now. In different ways. Not just blown away un-used. Wasted.
Any system-use of a heat moves that heat energy from the waste side of the equation
–>> over to the effective-use efficiency percentage side of the equation.
So, I could see his dismounted system; post ball mounted; loose other two points supported being gently shaken by a medium sized electrical generator. Gas fueling that electrical generator set.
Metal baskets of wood fuel to be used; resting, drying down, just simply set on top of the horizontal gas cooling tubes. Time for hopper re-fueling; just warm basket dump in.
Gotta’ think outside those narrow tight use-boxes too.
Gotta’ Operator think.
Regards
Steve unruh
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Steve,
in this video I just wanted to try the work of my gas generator with a motor that is equipped on a truck … The engine of that truck had a volume of 4.7 liters and the gas generator was removed from my red Opel and temporarily tied with a wire to the truck. So to say a trial test drive … 
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Yes Steve, we have other members in the past building of their gasifers that have used the heat coming off there gasifers to heat the wood in the back of there pickup trucks. Getting the wood dried out and warming it up. If you use this wasted heat off the engine exhaust that is all the better making it more efficient.
I remember the old roofing tar and road tar trucks used the exhaust from the engine to heat the tar up to use. Don’t let the heat just go into the atmosphere put it to use and use it up. This is how to get the most out of gasification DOW /Generating On Wood GOW. Making gasifers the right weight for its proposed applications that the gasifer will be needed to operate in.
This topic has got my brain / mind really thinking and yes it has to be out of the box of just what we have always have been reading or heard in the pass. My model is this there is something new under the sun for eash one of us, if we never have thought of it before. And thinking out side the box is one of those of the keys to finding it.
Bob
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Hello,
regarding the use of “waste heat”:
I have read in a book about a tractor of the German company Deutz made in the war. It was a special development for woodgas, not just a normal tractor with a gasifier attached.
The exhaust gasses were used to dry the wood: On each side over the rear wheels was a barrel for the wood through which the exhaust gases were plumbed.
Sorry, I have no photo at the moment.
I think this is a good idea, but never heard if it worked as intended.
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