A startup in Nova Scotia is experimenting with a technique to capture and retain more carbon in the ocean, using a new test facility to validate the idea. The ocean currently acts as a significant repository for surplus carbon dioxide, having absorbed approximately 30% of all human-induced carbon emissions since the 1980s. pHathom, the company behind the initiative, aims to enhance the removal of emissions from the atmosphere by capturing carbon dioxide and transforming it into a form that can be securely stored in the ocean for thousands of years.
The initial phase of testing will take place at the Huntsman Marine Science Centre in St. Andrews, N.B. Kimberly Gilbert, the co-founder and CEO, emphasized the importance of demonstrating the safety and effectiveness of the approach at a local level before scaling up. The company’s method replicates a natural process where raindrops absorb carbon dioxide from the atmosphere, becoming slightly acidic. When these raindrops come into contact with alkaline rock like limestone, a portion of the rock dissolves, reducing the water’s acidity and converting the carbon dioxide into bicarbonate. The resulting bicarbonate can be stored in the ocean for extended periods, preventing the release of carbon dioxide back into the atmosphere.
pHathom’s technique involves utilizing seawater and exposing it to the emissions from a biomass power plant to increase its acidity. The acidic water is then mixed with small limestone particles in a tank, converting the carbon dioxide into bicarbonate, before being reintroduced into the ocean at normal seawater pH levels. Other companies in Nova Scotia are also exploring variations of this carbon removal approach, known as alkalinity enhancement. pHathom’s method stands out for its use of concentrated carbon dioxide, enhancing efficiency in the process. The pilot project aims to capture 0.1 tonnes of carbon dioxide daily, with the treated water used for testing tanks to observe its impact on various marine species over a three-month period.
If successful, pHathom plans to expand its operations with a second test site in Nova Scotia next year, integrating the reactor into a building transitioning from a fossil-fuel boiler to a biomass system. Despite the potential of carbon removal technologies, challenges such as energy consumption and scalability remain significant hurdles. However, researchers and experts like Katja Fennel from Dalhousie University emphasize the importance of exploring promising removal technologies alongside efforts to reduce fossil fuel usage.
Canada has been recognized as a leader in ocean alkalinity enhancement research, with calls for international cooperation and regulatory frameworks to support such initiatives. Despite uncertainties in climate policies and economic challenges, pHathom remains hopeful that global awareness and necessity will drive action towards sustainable solutions.