> The result, after further processing, is a calcium carbonate pellet that can be heated to release the CO2. That CO2 could then be pressurized, put into a pipeline and disposed of underground.
I'm curious why you wouldn't just bury the calcium carbonate pellets at this point (or sell them, since they have value).
Pumping CO2 underground isn't a cheap or reliable process yet as far as I can tell.
> the company is planning instead to use the gas to make synthetic, low-carbon fuels.
I suppose the answer is that the synthetic natural gas is more valuable than the calcium carbonate. Seems like adding more steps than strictly necessary though.
Edit:
> In the United States, Carbon Engineering is eyeing a recently expanded subsidy for carbon capture and sequestration, which could provide a tax credit of $35 per tonne for atmospheric CO2 that is converted into fuels.
Missed this bit in the article. Regulatory arbitrage, which is a very good reason to add another step in your process, even if it's not strictly optimal.
I haven't done chemistry in years, but I think you can fairly easily reuse the calcium carbonate pellet once it has been heated. I imagine the cost of energy is significantly less than the cost of the raw resources.
Why go that far? Why not grow acres of a hardy fast growing plant like hemp or seaweed, fertilized with sewage water. Harvest and dry the plant, bale it, and stack the bales underground?
Or the Midwest farmers could bale their corn waste bury it instead of burning it.
Arizona could pipe in seawater and grow seaweed by the ton.
I'm curious why you wouldn't just bury the calcium carbonate pellets at this point (or sell them, since they have value). Pumping CO2 underground isn't a cheap or reliable process yet as far as I can tell.
> the company is planning instead to use the gas to make synthetic, low-carbon fuels.
I suppose the answer is that the synthetic natural gas is more valuable than the calcium carbonate. Seems like adding more steps than strictly necessary though.
Edit:
> In the United States, Carbon Engineering is eyeing a recently expanded subsidy for carbon capture and sequestration, which could provide a tax credit of $35 per tonne for atmospheric CO2 that is converted into fuels.
Missed this bit in the article. Regulatory arbitrage, which is a very good reason to add another step in your process, even if it's not strictly optimal.