Opening the factory to capture carbon thanks to sea water

Heimdal, a startup based in Hawaii, is developing a new method of carbon capture by the sea that will permanently store CO2 while reducing ocean acidification. Interesting Engineering reported on May 13.

Specifically, Heimdal pumps salt water into a machine that uses electricity to rearrange molecules in the water and reduce acidity. The acid is removed as hydrochloric acid, which can be stored and sold separately. This process produces hydrogen and oxygen byproducts, which can also be stored. Meanwhile, the water is returned to the ocean and helps capture CO2.

“Removing excess acid from the oceans helps bring CO2 back to its pre-Industrial Revolution state. This makes it no longer carbonic acid – the cause of ocean acidification – but converts to bicarbonate and carbonate These are stable forms of mineralized CO2 that sink to the ocean floor, where they can be stored for more than 100,000 years,” explains Erik Millar, co-CEO of Heimdal.

Oceans absorb large amounts of CO2, although the more CO2 they contain, the slower that process is because the world’s oceans become saturated. The ocean has absorbed a third of the excess CO2 that humans release into the atmosphere.

Last year, a team at the University of California Los Angeles (UCLA) announced that they were starting a startup called Seachange based on a similar idea to Heimdal. Their method converts CO2 in seawater into a shell-like material, allowing it to be stored permanently. This method was also born to help the ocean absorb more CO2 from the atmosphere.

Heimdal has put into operation a pilot plant powered by solar energy. This plant uses the infrastructure of an old desalination plant with the ability to pump large volumes of seawater. Its technology can currently capture CO2 at a cost of $475 per ton, Heimdal says, and the pilot plant can capture 36 tons of CO2 per year. The next plant is expected to be able to capture up to 5,000 tonnes of CO2 per year and operate at a lower cost of just $200 per ton. Heimdal aims to build this construction in Portugal or Dubai.

The technology to remove carbon from the atmosphere is still in its infancy, and the economics could be a big deal. Last year, the UCLA team said it would need about 1,800 plants to remove 10 billion tons of CO2 a year, costing trillions of dollars. According to the latest report of the Intergovernmental Panel on Climate Change (IPCC), by 2050, along with efforts to reduce emissions, the world will need to remove about 6 billion tons of CO2 per year to avoid these effects. worst effects of climate change.

Thu Thao (According to Interesting Engineering)