• cynar@lemmy.world
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    5 天前

    There are 3 use cases I’ve seen.

    • Making fossil fuel power stations “clean”.

    • CO2 recovery for long term storage.

    • CO2 for industrial use.

    It’s no good for the first, due to energy consumption. This is the main use I’ve seen it talked up for, as something that can be retrofitted to power plants.

    It’s poor for the second, since the result is a gas (hard to store long term). We would want it as a solid or liquid product, which this doesn’t do.

    The last has limited requirements. We only need so much CO2.

    The only large scale use case I can see for this is as part of a carbon capture system. Capture and then react to solidify the carbon. However, plants are already extremely good at this, and can do it directly from atmospheric air, using sunlight.

    • Arcka@midwest.social
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      3 天前

      It’s poor for the second, since the result is a gas (hard to store long term). We would want it as a solid or liquid product, which this doesn’t do.

      Why wouldn’t the device include or feed a compressor to liquidize the CO2? It takes just a little over 5 atm of pressure which is trivial.

      • cynar@lemmy.world
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        3 天前

        You also need to sustain 5 atm, with no leaks for years. Where is it being stored, and who’s paying for the maintenance? All it would take would be a bit of civil unrest, or corruption, and the work could be undone in mass.

    • gandalf_der_12te@discuss.tchncs.de
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      5 天前

      The only DAC variant i could see working out is if it takes the CO2 from high-concentrated sources (such as portland cement factories) and transforms it into something practical, like liquid fuel or methane.

      It could be leading to cheaper methane than from biological sources, because technological processes can have higher efficiency, and therefore lower prices.