Over the years we've looked at the issues surrounding concrete and the cement that binds it, most recently in March 17's "More On China And Their Fetishization of Sand":
Because the cement in concrete releases CO2 from both the chemical process—decomposition of calcium carbonate (solid) to calcium oxide and carbon dioxide (gas): CaCO3(s) → CaO(s) + CO2(g)
and because this reaction needs fairly high heat to occur (~850 °C) you get a double whammy, 4% of world CO2 production from the calcination and 4% of the world's CO2 production from creating the heat source.....MORE
And apparently about the same time I was writing that a couple teams were winning the X-Prize. I may have to adjust my priorities.
From New Atlas
A six-year competition to capture CO2 emissions from operational power plants and convert them into useful products has drawn to a close, and produced dual winners with technologies that promise to reduce the environmental footprint of concrete. The US$20-million Carbon Xprize has awarded cash prizes to two teams from North America, which were able to demonstrate how their approaches can remove meaningful amounts of CO2 and produce concrete that performs on par or even better than the traditional material.The Carbon XPrize started out in 2016 with nearly 50 teams from all over the globe, which was reduced to 10 promising finalists in 2018. These teams were then made to showcase their technologies at either a coal-fired power plant in Wyoming, or a natural-gas-fired power plant in Calgary, Canada, where they were tasked with demonstrating their approaches in industrial settings. Winners were crowned in both locations after converting the most CO2 into products with the highest value, and keeping their own CO2 footprint, land, water and energy use to a minimum....
....MUCH MORE
And the XPrize press release:
Oh well, there's still Elon Musk's money to shoot for:"Elon Musk to offer $100 million prize for 'best' carbon capture tech"
