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Comment by adammunich | Hacker News Reader

It’s only practical on mixtures with high co2 gas concentrations

From the abstract it seems to be very applicable to combustion exhausts (coal/gas plants) and consuming 5-10% of the combustion energy to recapture the CO2.

Hard to tell what is the required CO2 concentration without the full article. Typical combustion exhaust seems to be ~10% of CO2, https://en.wikipedia.org/wiki/Flue_gas

Edit: spelling.

Such as flue gases from fertiliser, cement, steel and power plants ... which make up a sizeable chunk of our emissions.

We should be targeting CO2 capture at point-sources wherever possible. Why wait until it's diffused into the atmosphere before trying to capture it?

Would inside a chimney work?

I wonder how research is doing to concentrate CO2 from the PPM amounts we have "in regular air"

There are at least two low-hanging fruits that make it "easier": CO2 is heavier than other important gases and mildly polar.

Plant lots of trees or similar, then burn them for electricity and capture the CO2 from the smoke.

Compared to a lot of the other proposals out there it almost sounds plausible.

Or skip a step. Turn the trees into lumber and build something with it. Long-lived wooden structures sequester carbon until they are abandoned and rot.

Why not just do a partial burn and reduce the remainder to charcoal? It would be much cheaper, require no chemicals, and the end product is pure carbon, which would be easier to store. You could literally dump it in a pile and deal with it later.

Making charcoal is not energy-positive and still only results in about 50% carbon capture, best case scenario. Burning it in a biomass plant with good carbon capture does better and displaces carbon-emitting generation processes at the same time. As an added bonus biomass plants are excellent 'baseload' type plants, a feature that wind, solar, etc are missing without expensive storage and complex management schemes.

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