I’ve moved this to it’s own topic, because I want to call you out. I’m sorry to say this, but you are either confused or outright deceiving with this claim. “Our team does not longer treat CO2 as a problem, but as a valuable source of renewable energy.” You’ve talked many times about burning CO2, reducing it, using it as fuel, etc. I don’t want to leave this uncorrected any longer. There are a lot of smart people on here who will back me up on this.
CO2 is not “energy” in any sense. It represents “spent” energy, consumed hydrocarbons. You cannot get more energy from CO2, it is IMPOSSIBLE. Physics is on my side here. You may convert it, but only by adding energy. Then when you burn that, energy added is now released - it’s right back to CO2 again. Any hydrocarbon fuel, including wood and charcoal, must eventually produce CO2 and water vapor.
You are not reducing the amount of CO2 even by recycling the exhaust, you are only slowing down it’s production. The same amount of CO will enter the engine, will burn, and the same amount of CO2 will be produced, and must be evacuated to the atmosphere. Recirculating it doesn’t make it vanish. You’re also ignoring C02 production at the charcoal retort. A pound of wood makes a certain amount of CO2 no matter what you do with it - even letting it rot away. This is positive news for all gasifiers - they use wood that would otherwise rot, and the same CO2 is released regardless.
In order to reclaim a flammable gas from C02 inside a gasifier, you need to input a large amount of energy, as well as hot carbon. This is a large thermal load and will cool things down (that’s good in a charcoal unit, and the only reason to do so). Energy is used to convert CO2 to CO. This energy is provided by - you got it - burning more charcoal, which means more CO2. It’s a zero-sum game.
Nobody has ever claimed that a gasifier will reduce CO2 levels. It’s foolish to claim so, because it won’t. There’s only one process that reduces CO2, and it’s not gasification…
Plants and trees love CO2, and consume it right back from us. A world filled with trees and gasifiers could go on forever - we call this being “carbon neutral”. Not adding, not taking away. A very different claim than “consuming CO2”. But this one is quite accurate, and well accepted science.
Sometimes gasifier folks will say it’s “carbon negative”. This doesn’t mean we’re consuming CO2. It refers to the biochar which is sequestered into the soil, where it is effectively un-burnable, won’t rot, and the C02 inside will never be released. Seen this way, eventually a world of gasifiers and trees would have carbon enriched soils, and less overall CO2 levels.
Let’s focus on the true positives of gasification (renewable energy, carbon neutral/negative) and not make misleading claims that violate physics.