An international group of researchers have identified the potential of 'concrete nitrogenation' in reducing nitrogen oxide (NOx) emissions in the construction industry.
Published in online journal Nature Cities, the study, named ‘Contribution of concrete nitrogenation to global NOx uptake’, highlights the economic and environmental benefits of nitrogenation compared to similar carbon dioxide (CO₂) processes.
The study estimates that concrete nitrogenation could decrease NOx emissions by 3.4-6.9 megatonnes (MT) annually.
By 2050, this cumulative reduction could reach 131-384MT, potentially offsetting 75-260 years of disability-adjusted life years lost due to premature death and diminished quality of life.
University of Birmingham co-author Dr Yuli Shan said: “Cities around the world, particularly those in the Global South, are experiencing extensive urban renewal, expansion, and modernisation - all inevitably creating atmospheric pollution.
“Between 1970 and 2018, global NOx emissions nearly doubled from 70MT to 120MT. Addressing and managing these emissions is crucial for enhancing urban health, fostering sustainable industrial growth, and ensuring environmental well-being."
China, Europe, and the US are identified as the main contributors to this initiative, with their capacity to foster circular economies and address atmospheric and environmental issues.
The researchers suggest implementing an emissions trading system for NOx such as the existing CO₂ framework, to quantify and validate the benefits of NOx sequestration accurately.
The practical application of concrete nitrogenation faces logistical challenges, particularly in transporting large volumes of materials and gases, noted the researchers.
To address this, the experts recommend leveraging existing industrial and commercial concrete carbonation systems to streamline the logistics network and improve the viability of concrete nitrogenation.
Leibniz Institute of Ecological Urban and Regional Development first author Ning Zhang said: “There is significant potential for concrete in capturing NOx. Applying this technology holds promise for rapidly urbanising and emerging industrial regions, as it can generate substantial economic value and curtail industrial NOx pollution in these areas.
“The proposed nitrogenated concrete material presents a promising integrated solution for mitigating air pollution and managing construction waste in industrialised regions.”