A startup based in Nova Scotia is currently conducting trials on a method to capture and retain more carbon in the ocean by utilizing a new pilot facility to validate the concept.
The ocean has been a significant reservoir for excess carbon dioxide, absorbing approximately 30% of all carbon emissions generated by human activities since the 1980s. pHathom, a company, is striving to enhance the removal of 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 company’s testing of this procedure is taking place at the Huntsman Marine Science Centre in St. Andrews, N.B. Kimberly Gilbert, the co-founder and CEO, emphasized that the pilot initiative is crucial in demonstrating the safety and efficacy of their approach locally before expanding globally.
pHathom’s technique imitates a natural process where raindrops absorb carbon dioxide from the air, turning slightly acidic. Upon coming into contact with alkaline rock like limestone, a portion of the rock dissolves, neutralizing the water’s acidity and converting the carbon dioxide into bicarbonate. Ultimately, this bicarbonate can be stored in the ocean for extended periods, preventing carbon dioxide from re-entering the atmosphere.
To carry out their method, pHathom introduces seawater to the exhaust from a biomass power plant, increasing its acidity. This acidic water is combined with small limestone particles in a tank to convert the carbon dioxide into bicarbonate, which is then reintroduced into the ocean with a pH level similar to regular seawater.
Various companies in Nova Scotia are exploring different versions of this carbon removal approach known as alkalinity enhancement. For instance, Planetary is running a project in Halifax’s Tufts Cove to raise the seawater’s pH by adding alkaline rock for enhanced carbon dioxide absorption. Another company, CarbonRun, is implementing a similar method along rivers in Nova Scotia.
The company’s method stands out due to its utilization of highly concentrated carbon dioxide, enhancing efficiency. Moreover, the contained reactor ensures measurable environmental impacts during the process.
During the pilot phase, pHathom aims to capture 0.1 tonnes of carbon dioxide daily, with the Huntsman Marine Science Centre conducting tests on the treated water’s effects on various marine species over a three-month period. Davide Asnicar, an associate research scientist at the center, highlighted the novelty of pHathom’s process, emphasizing the need to address numerous safety concerns.
If successful, pHathom plans to expand with a second trial site in Nova Scotia next year, integrating their reactor into a building transitioning from a fossil-fuel boiler to a biomass system.
Scaling up any carbon removal technology poses a significant challenge. The Intergovernmental Panel on Climate Change (IPCC) estimates that global carbon dioxide removal must reach between 10 and 20 gigatonnes annually to limit global warming to 1.5 degrees Celsius. However, concerns over geochemical obstacles and regulatory frameworks remain significant.
Despite the hurdles, the severity of the climate crisis justifies exploring promising removal technologies, provided efforts to shift away from fossil fuels continue. Canada has been recognized as a leader in ocean alkalinity enhancement research, with a recent Senate report urging the government to lead international implementation and regulatory efforts.
Though recent modifications to industrial carbon pricing have introduced uncertainty, Gilbert remains optimistic that the necessary global action will eventually materialize, emphasizing the importance of being prepared with proven technology when the time comes.