A startup in Nova Scotia is conducting trials of a method to capture and sequester more carbon in the ocean, utilizing a new pilot facility to validate the concept. The ocean already serves as a significant repository for excess carbon dioxide, having absorbed approximately 30% of all human-generated carbon emissions since the 1980s.
The company, pHathom, is striving 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. To demonstrate the safety and effectiveness of their approach, they will be conducting tests at the Huntsman Marine Science Centre in St. Andrews, N.B.
Kimberly Gilbert, the co-founder and CEO, emphasized the importance of showcasing the safety and efficacy of the local solution to address the global issue of climate change. pHathom’s method mirrors a natural process where raindrops absorb carbon dioxide, become slightly acidic, and upon contact with alkaline rocks like limestone, convert the carbon dioxide into bicarbonate. This bicarbonate can then be stored in the ocean for extended periods, thereby preventing carbon dioxide from re-entering the atmosphere.
The company’s method involves utilizing seawater and exposing it to the emissions of a biomass power plant to acidify the water. The acidified water is then mixed with small limestone particles in a tank, converting the carbon dioxide into bicarbonate before being reintroduced into the ocean with the same pH level as regular seawater.
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 highly concentrated carbon dioxide, ensuring a more efficient process. The pilot phase aims to capture 0.1 tonnes of carbon dioxide per day, with the treated water being monitored for its effects 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 their reactor into an institutional building transitioning from a fossil-fuel boiler to a biomass system. The scalability of carbon removal technologies remains a significant challenge, as global models indicate that substantial carbon dioxide removal is necessary to limit global warming.
Despite these challenges, the urgency of the climate crisis calls for exploring promising removal technologies while continuing efforts to reduce reliance on fossil fuels. Canada has been recognized as a leader in ocean alkalinity enhancement research, with a recent Senate report urging international collaboration on implementation and regulatory frameworks.
Although shifts in climate policies may introduce uncertainties, companies like pHathom remain optimistic that economic and environmental imperatives will drive global action in the future. When the time comes to address climate change effectively, they aim to have their technology proven and ready for deployment.