Giant air-sucking machines could be the solution to Earth's scary carbon dioxide problem

By Tanya Lewis

This company wants to solve global warming using giant fans.
Canadian company Carbon Engineering is building machines that suck carbon dioxide out of the air by pulling it through a fluid, where it can either be discarded or recycled to be used as fuel.

Trees do the same thing, but the fan machines would ideally be built in areas where you couldn't plant trees, such as deserts, Popular Science reported.

Technologies have already been developed for capturing carbon dioxide from smokestacks before it reaches and pollutes the atmosphere, for example. But Carbon Engineering plans to do it by capturing CO2 that's already in the air, like emissions from cars, trucks, and planes.

"We must do something about the rising levels of carbon dioxide in our atmosphere," David Keith, president of Carbon Engineering, says in a company video.

Fans pull air through the side of the machine, where it's combined with CO2-absorbent liquid that flows downward. They meet in the contacter, a structure composed of tightly packed, corrugated PVC sheets. When air flows over the sheets (which are coated with the absorbent liquid), the CO2 gets converted to carbonate, a type of salt. The arrangement of the sheets ensures that as much of the carbon-dioxide contaminated air as possible makes contact with the liquid.

The salt-containing liquid is then processed to get back the CO2, using technology developed by the paper industry. Carbon Engineering is developing a membrane-based version of this system that it says will consume less energy.

The CO2-absorbent liquid is fed back to the contacter, and a stream of pure, compressed CO2 is produced, which can then be discarded, or combined with hydrogen to make more fossil fuels (though this doesn't mean we should keep using these fuels).

Carbon Engineering already has a prototype machine - shown below - that can absorb the emissions from about 14 or 15 vehicles, which it hopes to scale up in the future by replicating the machine up to 20,000 times. That scale could capture emissions from 300,000 cars every year, according to the company video.