A startup in Nova Scotia is conducting trials on a technique to capture and sequester more carbon in the ocean by establishing a new trial facility to validate the method. The ocean currently serves as a significant repository for surplus carbon dioxide, having assimilated approximately 30% of all human-induced carbon emissions since the 1980s.
pHathom, the company behind this initiative, is striving to extract more 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 company will assess its strategy at the Huntsman Marine Science Centre in St. Andrews, N.B.
Kimberly Gilbert, the co-founder and CEO, emphasized that demonstrating the safety and efficacy of the approach is crucial, especially because climate change is a global issue that necessitates local solutions to be proven safe and effective within local environments.
The company’s method replicates a natural process where raindrops absorb carbon dioxide from the air, becoming marginally acidic. When these raindrops encounter an alkaline rock like limestone, a portion of the rock dissolves, reducing the water’s acidity and converting the carbon dioxide into bicarbonate. Ultimately, this bicarbonate reaches the ocean, where it can be preserved for tens of thousands of years, preventing carbon dioxide from re-entering the atmosphere.
pHathom’s technique involves introducing seawater to the emissions of a biomass power plant to increase its acidity. This acidic water is then combined with small limestone particles in a tank to convert the carbon dioxide into bicarbonate before being reintroduced into the ocean with the same pH level as regular seawater.
Various companies in Nova Scotia are exploring different variations of carbon removal techniques, collectively known as alkalinity enhancement. For instance, Planetary is implementing a project in Halifax’s Tufts Cove by adding alkaline rock to seawater to enhance its pH and carbon dioxide absorption capacity. Another company, CarbonRun, is executing a similar method on rivers in Nova Scotia.
pHathom’s approach stands out for its use of highly concentrated carbon dioxide, enhancing process efficiency. The company’s pilot phase aims to capture 0.1 tonnes of carbon dioxide daily, with the objective of observing its impact on various marine species over a three-month period.
If successful, pHathom intends to expand its operations with a second testing site in Nova Scotia next year, integrating their 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 industry experts emphasize the necessity of exploring promising removal technologies in the face of the climate crisis, provided that efforts to transition away from fossil fuels continue.
Canada has been recognized as a leading nation in ocean alkalinity enhancement research, with calls for the federal government to spearhead global implementation and regulatory frameworks. While policy shifts and economic uncertainties pose challenges, pioneers like pHathom remain optimistic about the eventual global adoption of carbon removal technologies when the need for action becomes imperative.