Leitinger wood gasifier

Jan,
“Yesterday I was delivering firewood all day (25 mile roundtrips) with Rabbit and trailer.”

DOW? A workhorse l wuld like to own…
I guess its that time of year for firewood preparation, althugh its a bit late for that here - sap is already in the wood. Althugh some customers still hire me and my father in law to do ligging for them, not knowing the beech will dry for at least a year untill its considered burneable.

About the hearth side, l am starting to get a feel why the oxy zone needs to be rather small in Imberts. Tar elimination. But l now saw a good air preheat and most of all a big enough reduction zone is what makes a good gasifier!
Althugh l hope l didnt speak too soon, still need to see what happens with ash in such a sistem.

Tom,
Sorry for the confusion. What l wanted to say is althugh there is of corse a considerable power loss, the drive characteristics are wery similar to petrol. The power is there when neaded. l think with a condensating hopper, its gonna get eaven better.

Here is a skech of my current hearth

The air gets preheated both from the woodgas and whatever heat is lost from the firetube WK style. Circulating in void, JO style :wink:

l did a video today, but for some reason, it doesent upload. Tryed 3 times.

l did all the tests today, idle, normal drive, fuel consumption, highway… for now, all looks right. Trafficlights are doable without hybriding, highway speeds are in the 90-100kmh neighbourhood, 110 is pushing it with mixed chunks. Steep long hills heat the system, as they did on the old gasifier. Fuel consumption does indeed seem to be less!

Allso, before, l was DOW with the air setting allmost all the way closed. Now, l had to drill a hole in the temporairy cooler plug to let more air in, and still drive with best power with the air setting allmost all the way open. Not sure whats the cause of that. Richer gas perhaps?

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That´s exactly the setup I use. You get access to a lot of surface area without adding material and weight with a separate heatex. The air mantle also becomes part of the insulation and very little extra ordinary insulation is needed.
Funny you´re learning English from Fins and Swedes :wink:

Yes, of course :grin:
I knock down all my firewood in the fall before snow. It´s been buried in snow until now just waiting to be cut and split. Ground is too soft in the spring for logging and too stressful to hurry before sap.

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Hi, Kristijan!
29.3.2017

You have achieved a lot of function per weight unit!

The bottom plate is of Siporex? The bottom geometry resambles of the newer GEK constructions.
Going flat will probably ask for frequent ash removal, as there is no “downdrop”.
From your description, it seems to have an easy flow and that is valuable!
The basket side can be vertical angleiron (selfprotecting)

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Jan,
We have about 2 winter worth of standing dry chestnut, for some reason it grows up to 5-10" thick, then dyes. It looks like cancer at the roots…
Your ground remains frozen?
Here the drought is terible. The ground is full of cracks, worse thain in August!

That was the goal Max. The previous gasifier weighted twice as the new one-puting stress on the rear end of the car.

Yes, the bottom is siporex. And yes, l borrowed the idea from GEK with a few twists of my own.
Actualy, with this build l tried to combine positive features from many sistems, GEK, WK, lmbert… while minimiseing there negative sides.

l am actualy thinking to go full size reduction, no grate what so ever. Ash shuld find its way in the bottom, while there are no real things to protect from the heat :wink: But one thing at a time.

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Kristijan, I´ve been staring at your drawing for quite a while now. That´s a very interesting reduction. I look forward to hearing about how it will handle ash in the long run. If it works good i might copy that for a low build in the future - with your permission of course :wink:[quote=“KristijanL, post:886, topic:2677”]
Your ground remains frozen?
[/quote]

Yes it still is. Starting to soften on the south sides. Sorry about your drought.

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Ha! I gained about 10 cm of hopper height thanks to it :grinning: A place that will be well used. But like you sayd, time will tell. Flowing in uncharted waters :wink:

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What is siporex? I am not familiar with that term?

Few years back I dropped a chain down one of those cracks. Went to the shed and got some baling wire to fish it out. When I got back I could still hear the chain rattling on its way down. :smiley:

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Thank you Kristijan for the sketch— helps very much. I went to the shop and looked at where I am and found I can add an air preheater like yours and JO. So the pre-heat is going back in only much lighter than the old system. ( thank you both )
Now I am questioning what I am doing with the reduction zone. I have made it much “smaller” than it was. I guess again I earn the name " Mary Contrary". It is a design that Max was helping me with a couple of years ago. It has an insulated reduction tube as Max suggested, but I think I picked the diameter on my own. I think the diameter was chosen based on a “ball theory” that JO posted some time back. ( the oxidation zone should be large enough to hold a ball twice as large as a ball that can be put in the reduction zone )
Yes JO, you got the humor in my comment about the word “mantle”. I only knew the meaning of mantle to be a shelf over the fireplace. Over the years Max had used it a couple of times and I let it go, but this time I had to look it up. TomC

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There is a chestnut disease (blight) that wiped out most of the American chestnut trees out. I hope you guys don’t have something similar running around, but I am guessing you do.

Tom Wobig, I’ll have to remember that tale, good one.
Pepe

Jim, siporex is insulative foam brick for houses, but it turns out it couples great with gasifiers.

TomW
I might have found your chan today while planting my future vineard, found a whole horse chain in one of the pits :wink:
Came a long way…

TomC,
Aftet some time I realized Max’s plans are to be kept stright as he puts them down. Any shortcuts and you bettet not folow them at all.
As for designing a system, i found out you realy have to only worship a few simple rules, evrything else can be purely your imagination. And belive me, its a lot more fun :blush:

Sean,
Sure hope not! I like roasted chestnuts with a glass of young wine wery much!

Anyway, l finaly uploaded the video. It took 4 times!

Since then, l made only about 200km on wood, seems to run a bit hotter. I have to check my gasifie-cyclone seal, suspect it might leak.
I did however empty the gasifier today, found out l nead a reduction insert to protect my restriction, and what l was most pleased, l found charcoal well above the restriction bottom level, which means the reduction is doing what it shuld-remain “fluidised”.
Allso, emptyed a whole 20l bucketfull of engine grade char out of it, now thats a lot of ready to be burnt charcoal compared to the previous ~3l!

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Great success Kristijan. I am amazed at the small size, and big performance, a winning combination. Thanks for sharing. A pretty drive too.

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Kristijan; Couple of questions — What do you mean by a reduction insert to protect the restriction?
Do you consider your restriction that funnel going from the oxidation zone into the char in your grate basket. What have you found above the restriction bottom level if you didn’t find charcoal?
Isn’t 20l of charcoal a lot in a 200km drive. ( maybe my conversion to metrics is incorrect — that would be about 5 gal in 100 miles???
Finally, what country were we driving in and maybe what part of it. I enjoy rides in different areas. TomC

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Thank you Carl!

Tom, yes, l plan to put a smaller cone inside the restriction cone, to be easyly replaced when it burns out. This one is welded.

20l is 5gal yes, but this is not slipt char!
In fact, no slipt char can ever be produced, as l have no grate.

This is the state l started with

This is the state after the reduction is well built.

In some way, its a downdraft wood/updraft charcoal gasifier combo :wink:
The upstream gas makes the char nice and loose, hope no more slag produce.

We were driveing in Šentjur, Slovenia :grinning:

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Ha, Kristijan I’m amazed you manage to squeeze everything down into that alu box. A really good job. Time to put some smiling miles on again.

Oh, a few questions:
Since you don’t have a grate - do you plan on emptying everything at every cleanout and just screen the ash out or do think ash will end up in the cyclone? What do your reduction “basket” look like. Rebar, angle iron, screen?

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Thanks, but not so fast! l am still at :smirk: , hope to get to :grin: soon.

Its still far from what l wuld concider a perfect system. Still need to make a final filter, a condensing hopper, a stronger starting fan and a few minor things.

l have the motor for the fan, and just made a call to a friend with a TIG welder, to make me a thin light ss or alu hopper.

While on the hopper… Do you guys think a small fan wuld provide suffisiant cooling to the hopper to condense water out? Keep in mind l dont have much more space for hopper cooling tubes inside, or outside of the alubox.

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I would make the hopper so it leaves just a 1 cm void to the alu box wall. Let it draw cool air in from the bottom and let the fan pull from the top or top side of the alu box. This way the heat itself will help the flow upwards. Important though to have the lower gasifier itself well insulated. The wind speed when driving will also help the chimney effect.

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Hmm l was thinking the other way, but you make sence. Perhaps eaven make a sort of a sail underneeth to catch the air and push it out under high speed.

Or, maybee combine two things and make a squirlcake style fan capable for startups, then redirect the intake and draw in fooling air for the hopper! A big venturi ejector shuld prodice plenty of cooling air!

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Thanks for the ride Kristijan :grin:

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