Does anyone know where to find information on the conditions for reconverting CO into CO2 in
syngas
I want to talk about the conditions that stabilize the gas at the exit of the generator grid
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Hi Thierry, in the book “Gengas” (woodgas) there are some about the “frozen equilibrium” and some about temperatures and reactions.
I think the English version is in library here?
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I think you want the Boudouard reaction. This is probably enough information to make your head spin without going over your head. And probably more detail then the Gengas book because we know more now. 
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Let me ask my question differently. What should be done to keep the maximum amount of CO and the minimum amount of CO2 in the gas coming out of the generator? I am speaking from a practical point of view. Should it be cooled quickly? Avoid stirring the gas?.. 
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Hi Thierry, cooled quickly is correct, a fast temperature drop, as often is achieved with primary air preheating, will make it less prone to “go back” to co2.
This is often called “frozen equilibrium” in older publications, because the reactions stops with falling temperature.
I don’t know if i remember right, but i think the gas should be cooled fast, below 900°c, to reach this.
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I cant remember for sure but l think its under 900c. More like 700. These equalibrium reactions are rather strange, usualy they are exponential in relation with temperature rise.
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Nedolgo nazaj sem menjal plinsko loputo na traktorju in ko sem razstavil celoten cevovod do sesalne odprtine, se je dobro videla usedlina ogljika za dušilno loputo. Lahko rečem, da vlažen in masten filter iz ovčje volne zadrži ves prah in cev na izhodu je bila čista, … Kristjan je povedal, da so nekateri uporabniki lesnega plina poročali o podobnem pojavu, očitno se to res dogaja.
Goran, torej plin, ki gre iz tople cone, je treba na hitro “zamrzniti” - ohladiti, kar jaz tudi počnem, a očitno še vedno ne dovolj učinkovito, oziroma je to “zamrzovanje” 100% nemogoče doseči, sploh pri hlajenju plina, ko predgrevamo. svež zrak, katerega količina je po mojem mnenju premajhna, no, konec koncev je vsak sistem potreben vzdrževanja in to čiščenje (enkrat letno) ne predstavlja posebnega problema.
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hi Thierry,
i am a bit confused about your question.
You want to have a low amount of Co2 in your gasifier outlet ?
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exactly Koen, I wonder what is the best way to condition the gas directly at the generator outlet
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Hi Thierry,
The best way is:
Keep the temperature at the reduction zone as high as possible,
Do not overpull ( no extra oxygen passing the reduction zone )
Avoid excess waterdrip. as moist ( water ) will reduce to H2 and O2 after the reduction zone ( still sufficient high to convert ) where as the O2 will burn the Co to Co2 and make the outgoing gas have higher temperature + wett.
Imagine a well stuffed tabacco pipe… keep the glowing at the place its ought to be, steady flow, sufficient sized reduction zone…
Best way, just keep it under the ashmelting temperature, try to have a steady gasflow, not to much ups and downs…
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Tone,
Not sure what you wrote, but I see your old filter barrel is quite rusty. My reactor barrel has not rusted at all inside yet. I has a phenolic epoxy coating (lining) inside. Of course it is not exposed to moisture like a barrel used as a filter would be.
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I observe thick deposits of soot stuck to the inner walls of my two cyclones. Knowing that the presence of soot is caused in part by the conversion of CO to CO2, I wonder about the effect of the cyclone on the quality of the gas…Could it be that the intense vortex effect generated by these small cyclones amplifies the conversion of CO into CO2?
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I suspect part of the reason between the published stop-reaction-reversal temperatures is LABs measured at atmospheric pressure. Versus engine drawn working negative below atmospheric actual gasifier conditions.
For the the thermal-chemicals changes we are working with this change of conditions I think is overlooked. Has been under-appreciated.
Took me learning refrigerants pumped auto AC’s to learn to appreciated just how much pressures changes contribute for energy transfers. In these systems it is nearly 100% for reversibility. Physics states thermal only wanted, or needed.
Steve Unruh
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Highly turbolent places like cyclones, throtle bodys and valves are just more prone to whipping out the nastyes out of the gas.
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