If it was a central nozzle centered in the hopper to feed the water, I would think tar may stick to the outside of the pipe. Then under the next fire and heat cycle the tar would loosen and drip, straight into the hottest part of the fire lobe? Granted it would only feed that tar that was stuck to the pipe that would be a good tar cracking system and more power made, I think?
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I think your ideas exchanging came to the spot of “tar recycling gasifier”. One of proven concepts is mentioned in the gasification bible shared on this site:
No matter of particular construction, my humble opinion is, that inner tube sucking the vapours from the top of hopper is the best approach.
- First, the tube is wide enough to prevent clogging.
- Second, it is easily removable fo cleaning.
- Third, it is heated by the surrounding flames and vapours which also prevents clogging with tar.
If air used for venturi suction at the top is preheated by output gas, then tar vapours will not condense at all. Heated inlet air also bring more energy into active zone, what may help to break more water comming along with tars from the top of hopper. And this is what all gasmen are seeking, isn’t it, ya?
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Thank you Kamil, I have never seen this drawing before very interesting. It would work in a WK Gasifier unit. Just place it above the other nozzle just out side of the metal melting charcoal zone. It could hang in the hopper from a chain so the whole nozzle could move back and forth alittle. Use a slyclone hose for intake air. It would keep the wood bridging down in the hopper.
Bob
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One of the guys here in Sweden (Gengas Werner), has done something that reduces the consumption of wood by about 1/4, and gets better gas, (more hydrogen) now I do not understand it, but it might work.
He has a wire mesh on outgoing gas from the cyclone that catches carbon particles and burns up the oxygen, which means that the water gas is not regenerated but the amount of hydrogen increases.
@KristijanL , do you understand how it works?
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Unfortunaly not. Talked to Tone the other day, l presented him a similar idea in wich one wuld pass hot gas trugh a catalyst (iron oxide pellets) in order to enrich the gas with methane, but the process looses energy as its exothermic and the side products are CO2 and water. I dubt that route is worth the while.
The process might be similar. Are you sure he has the wire mesh after the cyclone? Shuld be too cool down there for any reaction to happen…
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Aha! So if l get this right he preloads this device with charcoal that gets consumed later?
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No, it is the small pieces that are dragged along by the gas, which is stopped on the underside of the net and burns up.
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So the peaces that the cyclone is ment to catch anyways? Ok. Well then lm eager to learn more. Shuldnt be possible from phisic point of wiew. Not enaugh energy as the water gas reaction is highly endothermic. Unless he injects some oxigen with the gas, wich defeats the purpose…
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He explains that the oxygen burns up, so that hydrogen and oxygen do not go together to form water. (I think)
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But thats the job of the reduction zone. Wich this is too… But it requires vast amounts of energy and there shuld only be trace amounts of free oxigen in the gas of a well designed gasifier. It wuld make sence to me if he tryed to “crack” the remaining water in the gas via water gas reaction but here lm lost
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Friends, I am really impressed with how many different procedures you have given, there will be a lot to consider. Kamil is a very interesting sketch, it just gets complicated in my head. Jan, do you know how the heart of the gasifier is made? I guess it has a low and wide fire zone (similar to Joni) and air nozzles near the grille, so pyrolysis and oxidation is done in a gasifier and the reduction is only partially and partially in a cyclone. There are bottom-up gasifiers, where all the gasification processes take place on the surface in a narrow wide layer, but the gas is not so clean.
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He has made tables on how the generators should be according to engine size, today he has a cheva 4.3 liter engine in one of the cars.
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I have to agree, if you are getting any kind of live charcoal into the slyclone and can be burned up, there is some over pulling of the gasifer going on passed the charcoal bed reseve. This should be causing a heater effect in the gasifer. This is not good causing weak gas production. The charcoal bed is to shallow after the restiction zone. It needs more reserves.
On my Gasifier I can have 1360°f to 1500°f or 737.8°c to 815.6°c at the grate. By the time the dead gases have moved from the grate to the drop box the temperature has cooled down to 400°f to 450°f or 204.4°c to 232.2°c ranges. If there was live sparks of charcoal in this area, it would weaken my gases by burning them up because there is oxygen present. It is possible to have high heat at the grate but no oxygen at the grate left to burn gases. If a trace of charcoal is still burning as it passes the grate it should be out in less then a second. No oxygen to burn no more heat increases.
Bob
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The reaction of producing methane is possible only at temperatures above 400 C⁰ and in the presence of an iron catalyst … So I am not too sure that such temperatures can be reached in a cyclone. And given that the reaction proceeds with the absorption of energy, and adding to this the loss of heat during transportation and contact with the walls, I am sure that the final and total efficiency of the system will be much less for Imbert and WK.
I must also add that the product of the reaction of obtaining methane from the generator gas is molecular carbon, that is, soot …
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(During combustion, it becomes water gas, ie the hydrogen is released from the oxygen, however, these are drawn to each other later in the process when it cools down. I put in a net in the cyclone that caught the carbon which continued to glow, this means that the released oxygen is used in the process and the hydrogen gas remains in the gas.)
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Jan, this observation of his is not correct. He imagines a water molecule just splitting in to hydrogen and oxigen in a gasifier wich is not the case.
Whats happening is carbon (charcoal) wants to bond with oxigen. A lot! Just like in an iron ore smelt, where carbon is used to steal the oxigen from the iron oxide ore, leaving iron behind. Here, carbon steals the oxigen atom from a H2O molecule to form CO leaveing hydrogen behind. Carbon just wants that oxigen more.
Ok l just came up with a love story called “The Gasifier love triangle” 
bear with me…
One day, this marryed couple walked in a bar called “The Gasifier”. They were named Mr Hydrogen and Mrs Oxigen. At the bar, there was this bartender called Carbon. He was glowing with atraction and as things heated up in the bar, Mrs Oxigen found Carbon way more atractive thain Mr Hydrogen. The marridge was over and Mr Hydrogen left the Gasifier bar alone, and Miss Oxigen hooked up with this new guy Carbon.
The story culd end there but then one day the shamed, now single Mr Hydrogen decided to visit this new bar, called “The Iron Catalyst” to much of his surprice, he met his Ex wife and the guy that stole her there. They talk and drink for some time, things start to get hot. But the thing is, “The Iron Catalyst” is in fact a swinger bar. Sufficiantly intoxicated, they decide to give it a try, all together for some experimentation action 
but things dont go as planned… At least not for Miss Oxigen. To spare the details, she left the swinger bar alone that night… CH4 was the cause
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Joke aside. I belive l found what Werner is up to. My thinking is he probably has a too small reduction zone for his engine. A lot of unreacted gases pass trugh, along with a lot of heat. Those can then react a second time in his cyclone. In a way, his cyclone acts as a second reduction zone for the gases that hadnt had the time to react in the actual gasifier.
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Ok, that was a good story anyway.
Wondering if I have the same problem, mine is over 300c after the cyclone already after a few km.
A little strange that all the old tables about Imbert have such short spaces both above and below restriction?
Wayne has shown that it works with more space.
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I suspect its because a true lmbert isnt just the hearth. Its the whole combo. Heated hopper will pre-char the wood before it comes to the hearth. This means the actual hearth can run hotter, hotter means faster, faster means it can be smaller. Just a speculation…
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