Here’s an article on a venture backed by Bill Gates to remove CO2 from the atmosphere.

I’ve always been skeptical of these types of enterprise, on the basis of sheer mathematics.  In this case, the technology involves collecting and baking biomass into rectangular solids the size of shoeboxes, covering them with an impenetrable coating to prevent decay, burying them in deep holes, and monitoring them indefinitely.

In 2025, the company predicts it will capture 15,000 metric tons of CO2, which 1 out of 2.5 million of the world’s annual CO2 emissions.

If I were in change of all this, I would simply grow trees, and turn the wood into building products designed to last at least 100 years.  I think it’s a reasonable assumption that the next century will bring us to a place where we have vastly different issues in limiting/removing CO2 emissions.

Direct CO2 Capture