Atmospherica uses a biotechnology-based solution for scalable carbon dioxide removal. We grow photosynthetic, shell-forming micro-algae in a protected environment, where the calcium carbonate produced can be continuously harvested and removed from the ecosystem. We utilize our patented, low-cost photo-bioreactor system which has an excellent track record in growing photosynthetic algae. We couple the photo-bioreactor with a particle filtration system to provide a novel, integrated carbon dioxide extraction facility. As the system is based on photosynthetic, naturally occurring micro-algae and a low fabrication- and operational cost photo-bioreactor system, it is an intrinsically scalable solution for high-volume carbon dioxide extraction.
In addition to its scalability, a major advantage of Atmospherica’s technology is that its final product is calcium carbonate, which provides a highly stable reservoir for CO2: Naturally-formed calcium carbonate deposits are known to be stable for tens of millions of years.
Experimental Demonstration at Greenhouse-Scale: Building on our decades of professional experienced in biosystems engineering and operations, we successfully cultured multiple species of Coccolithophores. First, we studied growth conditions in table-top, indoor experiments (50 mL volumes); we then constructed an indoor photobioreactor (ca. 5L volume, a smaller-scale version of a full-volume greenhouse photobioreactor. We successfully identified conditions in which rapid, exponential growth was measured until predicted saturation levels! These experiments strongly supported our models. Then, we transitioned to a full-scale photobioreactor (250 L total volume) in a University of Arizona greenhouse. Very quickly, we again reached exponential growth with growth rates close to the model-predicted growth rates! These outcomes were very exciting as they demonstrated successful 5,000x scaling with no significant loss of efficiency! The experiments ran very robustly, with very minimal maintenance for several months. At the completion, we harvested deposits rich in CaCO3 for laboratory analysis and for use in cement production.
Laboratory Analysis Confirmed Healthy Cultures and CaCO3 Production: We use standard culture monitoring techniques (e.g., cell counts, optical throughput measurements, scanning electron microscopy) to monitor growth rates and culture health. These confirmed excellent culture health, very high growth rates, and provided important data to test and calibrate our models. We also conducted multiple state-of-the-art analytical measurements to assess the composition of deposits and quality of CaCO3 extracted, including thermogravimetric analysis (TGA), Raman spectroscopy, compositional microprobe mapping, and scanning electron Microscopy. These measurements confirmed high-quality CaCO3 production by Coccolithophores, fully in line with expectations.
We successfully demonstrated production photosynthetically-produced limestone at greenhouse-scale level and showed that we can produce high-quality carbon-offset cement with the extracted deposits.