Leonardo DiCaprio-backed company turns CO2 into synthetic limestone

synthetic limestone

Blue Planet has developed a carbon capture and utilization system that permanently removes carbon dioxide and transforms it into synthetic limestone.  

The process captures carbon dioxide emissions from bioenergy, natural gas and coal-fired power plants, steel mills, cement plants and refineries, as well as directly from the atmosphere. Blue Planet then converts diluted carbon dioxide captured from the gas streams to carbonate for mineralization as a synthetic limestone.

According to the company, the synthetic limestone can replace naturally-mined limestone aggregate as the principal constituent of concrete, permanently isolating the captured carbon dioxide. 

“New technologies are one of our greatest tools in reversing course on our continued path of climate change,” said investor Leonardo DiCaprio. “I am pleased to support the continued dedication and innovation at Blue Planet in our shared push for a more sustainable future. New processes and scalable systems like theirs are instrumental components of reducing the impact we have on our planet.”

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Blue Planet’s proprietary process creates synthetic limestone sand and gravel that can be used to make carbon neutral and carbon negative concrete, with the same structural integrity of conventional concrete. 

By offsetting the carbon footprint of the cement in concrete, Blue Planet’s aggregate more than compensates for the cement component’s carbon footprint, making the concrete a net carbon storage sink. 

The process also creates upcycled concrete aggregate as a by-product, reducing the need to mine and consume aggregates. 

Unlike other carbon capture methods that require an energy-intensive carbon dioxide purification step for liquification, transport and injection, the Blue Planet system directly converts the carbon dioxide diluted in flue gas to carbonate, which avoids significant costs and parasitic loads of purifying the carbon dioxide gas from a dilute stream in order to liquify it for underground disposal. 

Instead, the synthetic limestone rock produced is distributed to concrete plants for incorporation in concrete, where the carbon dioxide is stored permanently. 

Most carbon reduction schemes are not permanent, and instead allow the captured carbon dioxide to re-enter the atmosphere at some point. The production and distribution of synthetic aggregate for concrete make the operations profitable. The plants can be financed, owned and operated under well-established project financing structures without subsidies.

Blue Planet’s first plant is being constructed in  California, adjacent to a natural gas-fired power plant and the Sacramento Delta, for barged material transport of raw materials and finished goods. 

Blue Planet concrete has already been incorporated at Terminal 1 at San Francisco International Airport (SFO), establishing a model for cost-neutral public procurement of low carbon building materials for carbon mitigation.

Blue Planet Systems Corporation is a cleantech startup company located in Los Gatos, California, that is developing technology, products and services related to economically sustainable carbon capture and mineralization, whereby carbon dioxide is permanently sequestered in building materials for beneficial reuse, specifically as aggregate for concrete.