A startup in Nova Scotia is trialing a technique to capture and retain more carbon in the ocean, using a new test facility to validate the concept. The ocean serves as a significant reservoir for surplus carbon dioxide, having absorbed approximately 30% of all human-induced carbon emissions since the 1980s. pHathom, the company leading this initiative, aims to further draw emissions from the atmosphere by capturing carbon dioxide and transforming it into a form suitable for secure storage in the ocean for thousands of years.
The trial of this method 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 efficacy of their approach at a local level due to the localized impact of ocean interventions on communities. pHathom’s process mirrors a natural occurrence where raindrops absorb carbon dioxide from the atmosphere, becoming slightly acidic. Upon contact with alkaline rocks like limestone, a portion of the rock dissolves, neutralizing the water’s acidity and converting the carbon dioxide into bicarbonate.
The company replicates this natural process in a controlled reactor by exposing seawater to the emissions of a biomass power plant, acidifying the water. The acidified water is then mixed with small limestone particles in a tank, converting the carbon dioxide to bicarbonate, which is subsequently reintroduced into the ocean with the same pH level as regular seawater. Other Nova Scotia companies are also exploring variants of carbon removal techniques, such as alkalinity enhancement. Planetary and CarbonRun are among the companies conducting similar projects in the region.
pHathom’s method stands out for its use of highly concentrated carbon dioxide, enhancing process efficiency. The pilot phase aims to capture 0.1 tonnes of carbon dioxide daily, with a focus on observing its effects on marine species over a three-month period. If successful, the company plans to expand with a second test 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 these technologies, challenges like energy consumption and scalability remain significant hurdles.
Katja Fennel, a lead investigator in oceanography, underscores the need for rigorous testing and scaling of carbon removal technologies to address climate change effectively. As the world grapples with the urgency of the climate crisis, ensuring a transition away from fossil fuels is crucial. Canada has been recognized for its leadership in ocean alkalinity enhancement research, yet uncertainties in policies like industrial carbon pricing pose challenges to the financial feasibility of carbon capture projects. Despite these obstacles, industry players like pHathom remain hopeful that global action will be inevitable as environmental and economic imperatives align.
