For the past couple of years, the rise in greenhouse gas emissions has led to increasing concern about the possibility of negative effects on the climate. However, Calera, a recent start-up company based in Los Gatos, California, has come up with a way to take carbon dioxide (one of the major greenhouse gases) and other emissions from coal power plants, combine them with seawater, and process them into cement and fresh water, a method called Mineralization via Aqueous Precipitation (MAP). The principle behind Calera comes from founder Brent Constantz’s research as a graduate student at the University of California at Santa Cruz, where he studied on how corals use carbon dioxide to build their skeleton.
The great thing about MAP technology is that it can use readily available waste from the combustion of coal in power plants to manufacture useful products. These waste products include flue gas, containing carbon oxides, sulfur oxides, and fly ash (small particles of ash), geologic brines, and waste water. When these leftover materials are not sufficient, Calera employs Alkalinity Based on Low Energy (ABLE) – a technology used for chemical production of NaOH and HCl using salt and electricity – to supplement it.
Calera’s work has primarily been done at a pilot plant in Moss Landing, California. However, its partnership with Bechtel Power Corporation (as of December 2009), a major engineering company, signals its readiness to tackle the challenge of establishing successful commercial plants. As soon as next year, Calera’s first commercial plant could be in operation.
Calera’s main selling point is that it generates useful products with a coal-driven process that takes more carbon from the atmosphere than it releases into it, in an economically efficient manner. Calera cement and aggregates are currently used in road base, as well as asphalt and concrete pavements. After the MAP process, reverse osmosis can be used to generate fresh water as yet another product of this incredibly multifaceted, environmentally friendly process. And all this without any alternative forms of energy!
To learn more, check out www.calera.com, and http://www.nytimes.com/2010/03/22/business/energy-environment/22cement.html?dbk