What about to use pipe coil for air input?
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Hello Tone.
You concept is valid.
This was done in the late 1970’s? early 1980’s? by an Australian man Kurt Johanneson (sp).
He used three thin “shells” as he called them on his rear bumper mounted raw wood system.
He needed light weight; and promoted the outer shell as a stay touch not-hot safety measure too.
Functionally his was a completely different system than yours. Center top down single air brass air nozzle. Water drip cooled in his predominantly arid (dry air) environment. Had a sweeper arm grate.
Takes a master sheet metal man to fabricate air and gas tight. We was. You are.
Others trying to duplicate off of his published plans set - - not so skilled.
Regards
Steve Unruh
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Kamil, in the post from April 25, one of the possibilities is drawn, an internal thread inside, in which a twin screw is screwed, which compresses and slightly deforms the outer casing, thus sealing the joint with the inner chamber.
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Steve, I also want to achieve as little weight as possible, an empty gasifier of 100 liters capacity should not exceed 50 kg, well, another advantage is also a quick start, because not much mass is heated, but I don’t want to lose the quality of operation by saving weight. The thin sheet metal casing inside keeps the hot gases next to the “heat” exchanger and reflects the heat radiation, I think most of the hot gases will move up inside,… and then there is the outer casing which also reflects the infrared radiation inside , but partially cools the hot gases. I’m also thinking about adding a cyclone, which will also be a heat exchanger, because a lot of ash and charcoal dust is produced during the gasification of small twigs and bark, so it is necessary to frequently rinse the refrigerator, where these particles are deposited.
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That is my barrel in a barrel in a barrel gasifier design I was trying to come up with but failed. You did it great job. And you have your center nozzle with the circle upper nozzles too. Looking forward to this build for sure.
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This is not yet the final version of the plan for making the gasifier, today I will mention only one detail, namely the “removal” of ash. As I said before, I use a variety of fuel, with a lot of bark and dust, which also creates a lot of ash and coal dust. If I give an example from my tractor, when operating for about 20 hours, at least 20 liters of ash mixed with fine coal are formed, and inside the hot zone around the lower nozzle, fragile pieces of solidified ash are formed, which cannot be removed by the flow of gases, so it is necessary to After 50-100 hours of operation, empty the gasifier and remove these pieces. Here I am attaching a sketch that shows one of the options for solving this problem…when I turn the handle, openings open through which larger pieces can fall or be crushed during rotation…the operating position is the closed opening.
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What will you use for a packing to keep that shaft on the crank air tight. I had something like that on the original WK I built and it was always an issue. I used a microcord packing that was impregnated with high temp silicone.
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Hello Tone.
So you will still be allowing the formed fuel gases to collect and rise up above the your rotating disc “grate” level, yes? Grate is also in English an action verb word meaning to mechanically reduce down into strands and curl’s.
If so Tom the lower settled inert ash and clinkers bits will go a long way to shaft sealing. In BenP’s works the shaft is supported on a collar welded on. The shoulder of the collar resting on a welded on floor tube support flat end. No packing. Just these ~5 mm wide flat edges against each other doing the majority of the sealing. His grates, the char stack above bearing down creating the downward sealing force. Ash stack built up surround this support doing the leak sealing.
Tone: I actually do wearing both a belt and suspenders. So a guy like me says you’d be wise to put on an external compression spring to always be pulling downwards.
KurtJ. made his whole top and bottoms out of large agricultural formed plow discs. Sealed ash seemed to allow him to perimeter seal the whole lower hinged for ash dumping. He shows he did inner layer insulate his lower disc bottom plate.
Just a side port would be adequete for manual drag tool pulling out ash removal.
Regards
Steve Unruh
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tom, i think tone will find a good solution for the stuffing box…how always…
another solution would be to make the rotation mechanic inside, and move it from the opened ash door, especially this shaker is only for clean out and not for shaking during driving…
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That is a great idea. Just make the intake air tube come up and Y then go up into the bottom plate like your older design. Have cut outs and the rotating plate over it the lever below the chamber area for rotation of the plate for clean outs.
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Even with the bottom air intake style with the vertical tubes it can be done with a ash clean out bottom. Using a internal lever.
It was not drawn to scale.
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i will absolutely not steal the pleasure of constructing , tone…
i would build the mechanism inside in this way…could be also shaked from outside with a additional lever through a stuffing box in the sidewall of the gasifier barrel…but to whom i tell this…?
seeing your gasifier hearth and bottom nozzle- gas pipes grate construction, i thought there would be only needed for more comfortable cleaning needed some clean out method without emptying the whole gasifier…but how to make it …with the double bottom…?, you showed it in wa to make air channels to the center nozzle instead the complete double bottom…
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Friends, thank you for the sketches, well, the new construction of the gasifier has an air intake at the top, so the bottom is free for making openings for cleaning, here it is also necessary to think about the compact design of the inner part and the outer casing, now I have this attachment made with a screw connection for the inlet air, and in the case of the new construction, the lever for rotating the disk, which I loosen when cleaning, would serve for this. A compact design is essential so that the inner part does not oscillate too much and thereby break the welds or the supporting thin sheet.
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here is a sketch, above is a flat metal-to-metal seal and a metal bushing, below the joint is sealed with high-temperature sealing cord, and at the bottom is a flat seal between two threaded nuts that compress the sheet metal of the outer casing.
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In the sketch of the gasifier, I purposely drew the air inlet connection and the gas connection close together, here I intend to attach a cyclone for extracting ash and small particles of coal from the gas, so that they do not settle further in the refrigerator. I am also thinking of making a double jacket made of thin metal for additional preheating of the air, well, the installation of the cyclone itself, which rests on two screw joints, is also an advantage, which represents a compact installation.
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Tone, you need a cone and a pot under for un-speeding. This way all is turning and sucked up in the central pipe.
Someone else posted a design, Kristijan used it in his Mercedes, anyway, a design I want to test some day. The key factor is a horizontal plate between separation and collection. Very simple design and you dont have to make a cone.
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I just realized that I do not need a rotating plate. With the clean out hatch open, I can just have a slid out plate under the Double plate that feeds air to the nozzles. Slide the plate out and the ash and klinkers pieces will fall down to the bottom on clean outs.
Trying to keep it in the K.I.S.S. mode of building this Gasifier.
The air intake will lock down and seal with a threaded pipe fitting. It will pull down the whole fire tube top plate down and seal it tight to the lower barrel on top and at the bottom.
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JoepK.,
There has been an introduction on the DOW; and talk about the Thien Baffle system for ash and soots separation.
So far none has given use-feedback-expreinces for woodgas systems.
Developed by J. Phil Thien
His information is here:
https://www.jpthien.com
Load and scroll down to: “Cyclone separator lid w/ cyclone separator baffle”
Regards
Steve Unruh
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Thanks, that is a new one. Got a link long ago from Dutch John about cyclones (now I know where he got it from 
), works like a charm but you really need that cone.
This system was talked about in another thread, works ok too. The advantage in my opinion is the lower speed of separation and therefor less pressure loss, together with simple fabrication.
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