Properties of a good wood gasifier

Today is the day for the test run, the system operated for 4 hours under a load of 3 - 4 kW, the operation was stable.
Is it normal for the hay in the filter to get wet, or is this a sign of an oversized pipe in the firebox?

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Congratulations Tone!
Chips for fuel? What do they look like? Size, shape?
Is that bucket hopper condensation? If so, what prevents air to get sucked into the hopper?
Wet hay is certainly normal, and a good thing as soot sticks to it even better. At shutdown some of the soot will get washed down as condensation drips down.
What’s the size of the motor and generator (kW) ?
Lot’s of questions. I feel like @TomC :grin:

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Thanks Jo, the engine is an older Kubota 400, newer models are expected to have 7.5 kW at 3200 rpm, this probably less. In the experiment, the generator rotates 2300 rpm and produces about 3.5 kW. The rated power of the generator is 5kVA. When testing only on diesel fuel, I slightly increase the load by 0.5 kW, so the power when working on wood gas is reduced by 13%, otherwise these are the first measurements, which excites me.
A basket in a bucket, … I don’t understand that question. Do you mean the filter?
The fuel is wood chips of all sizes and shapes.

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Thanks Tone!
That’s incredible performance.
You run a small amount of diesel for ignition, right? How many % do you estimate the consumption is?

At 1:05 you show us a bucket of what looks like hopper juice - tary condensation. If the hopper drain drips into a bucket, how do you prevent air to sneak in? Most of us use a sealed container.

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If the tube is under water I don’t know that could produce enough vacuum in the hopper to pull it up the 2 foot is so to the hopper, pressure would probably equalize and as condensate fills the tube it slowly pushes out. Just a guess

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Yeah, that’s right, as Marcus wrote, I had the hose clogged at first, but when the water came out, I put it in a bucket. There are automatic siphons for air conditioners.https://sl.capaparda.com/sifon-za-klimatsko-napravo-naprava-in-vrste-15435

This one, as you said, Jo, there is oil for ignition, I limited the injection pump so that the unloaded engine still worked with difficulty, I estimate 10%, and the speed adjustment lever is set to max, so the oil is constantly dosed, unless the engine exceeds the revs, you can easily see in the clip when I reduce the setting for a moment, the engine immediately stalls and I have to turn off the heater to recover.

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Hey Jo, are you already flirting with your forest tractor to equip it with the pleasant smell of gas? :grinning::black_heart:

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Great job Mr Tone,
I missed that above one “picture” was a video link.
Great that you are blackened hands feeling system conditions. You will always have the hands, and memory experiences, with you, in your pocket.
Then program your smeller, and taste buds too.

Gauges. Meters, can, and will fail. Range shift and lie to you.

Your wood stocks inputs are certainly varied. Chunks; splinters; slivers; and sprig sections.
For actual, true chipped fuels look at the Swedish guy with the Ford pickup JanA recently put up on his topic and you’ll see why he had to evolve a chip mover mechanism. True 100% wood chipped fuel wants to tar glue itself together: then and not settle: not compact; and move at all.
Regards
Steve Unruh

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Tone, I’ve given this a lot of thought. I still have the little Rabbit gasifier sitting in the garage and there’s nothing wrong with it. I think it would fit like a glove.
However, I’ve come to the conclusion it’s not worth the effort. I don’t run the Fergie many hours a year, it was rated 20hp 1947 and most likely with a rather low compression. Power and compression is probably even lower now and I need 100% gasoline power now and then. Also, to be able to utilise the governor I would have to run woodgas through the carb. It’s doable, but a lot more work with maintence.
If gasoline prices keep skyrocketing I may change my mind, but I’ll keep it stock for now.
Resent years I have mostly left the tractor in the woods for difficult terrain and let the Mazda do the long distance towing on wood.

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Hello Mr. Steve, you are right when you mention the measurements, otherwise after the first attempt and the joy of the operation, it all surprises me, but as you say, time will show the real situation.
Don’t mind if I philosophize a little more.
-If we compare diesel and otto engine with the same displacement, the otto engine has somewhere 30% more torque, because there is much more hydrogen in gasoline, which uses less oxygen (H2O or CO2) for combustion
-if the petrol engine runs on wood gas, its torque is reduced by 40-50% (I don’t know if this is true, I estimate)
-if the diesel engine runs on wood gas and 10% oil, what is the torque here? High compression of the engine and intensive ignition of the mixture with diesel fuel causes good and fast combustion of the mixture and thus good engine efficiency. My opinion, observations and rough measurements show that in this mode the diesel engine loses 10 to 20% of its torque.

Don’t take my word for it, over time the numbers will be realistic when I connect the generator to my house heating system and the electrical part to the mains.

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Hey Jo, I thought your Ferguson was diesel, but you’re saying it’s on gas, do I get it wrong? Namely, I intend to add wood gas to my tractor when I learn to operate the system.

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Right, it’s a 1947 gasoline Fergie. I think diesel Fergies weren’t introduced until early 50s.

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This afternoon I harassed Kristjan for half an hour with my impossible questions about the processes in the gasifier, I always get some interesting information, good because he has a lot of patience.


Otherwise, I go the way of Jeop, I replaced the synchronous generator and replaced it with an asynchronous but awkward one as I am, I broke the connector on the fridge.



I tossed a little wood lying in the yard and chose suitable pieces for the construction of the facility where the gasifier will stand. The night is too early, and tomorrow is a free Saturday.

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Little change of work program, from iron to wood,. I’m attaching a couple of pictures here, I hope you don’t laugh too much :grinning::relieved:







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Hello Tone,
This is to be the engine generator head base, yes?
If so, no laughing from me.
Metal ships they learned well to wooden skid mount the axillary engine-generators.
Sound and vibrations Isolation.

Wooden engine-generators enclosures can work to for sound and vibration damping unless made to be musical instruments. Wooden flat panels do this.
S.U.

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I have already mentioned in the second topic what my brother Primož (doctor of mechanical engineering and extraordinary mathematician, physicist and top connoisseur of materials, …) suggested, namely the mixing of water vapor between fresh air in the gasification of wood. Since we all know that this process produces an excess of water vapor, which we condense and discharge from the system, at first glance this proposal seemed pointless to me, but after some consideration I find it to be very good. I drew a cross-sectional sketch of the heart and divided the bands to form individual gases. The closest to the nozzles, where dry hot air hits the burning charcoal and expels other gases in the middle, only CO can be formed, in a narrow band where the temperature is still very high, the conditions for the formation of CH4 and CO, the next is the H2 band and CO and in the middle is the band where H2O no longer decays. So, if I captured part of this water vapor at the top of the gasifier and mixed it with the venturi effect on the nozzle, the hydrogen content in the gas would increase, while at the same time I could reduce the diameter of the fire hose by the same power consumption. Comments are highly welcome.

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Sketch for rearrangement in the gasifier.

I will definitely try this, but not right away, it will work as it is first to take longer measurements.

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No comment, just speechless. Is this woodgas 3.0? If the WK is 2.0. Cant wait to see your results.

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Hi Joep, as I believe you are very busy, just like me, the job, the daily work, … and there is less time left for experiments, so the project progresses more slowly, but slowly gets far.
:relieved::grinning:

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Tonight we decided not to work but cut 2 m3 of wood for the Atmos. The plan was one IBC but music full open and full speed ahead. We were having fun. I asked my college , if I wouldnt pay you tonight you would be here anyway. Yes, for sure, he said without hesitation. So, lot of fun but no work and no experiments for me. But you are going strong! Keep it up! Woodgas 3.0. I have no clue, but is sound logical. The same what is done in charcoal gasifiers. The trick is to have the water right were it should be. Only my thoughts, cant prove anything. Let that to the real experts.

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