A new study reveals that adding nitrogen to concrete could significantly reduce global levels of harmful nitrogen oxides (NOx) produced by the construction industry. Researchers believe concrete nitrogenation could cut NOx emissions by 3.4-6.9 megatonnes (Mt), accounting for 6-13% of industry-related emissions in 2021. By 2050, this process could reduce NOx by a total of 131-384 Mt, equating to 75-260 years of improved quality of life and reduced premature deaths, measured in disability-adjusted life years (DALY).
NOx are reactive toxic pollutants that contribute to acid rain, ozone layer depletion, and pose significant health risks, especially related to respiratory diseases. These pollutants are a major contributor to air pollution-related mortality.
The findings, published in Nature Cities by an international team of researchers, suggest that commercializing nitrogenation could offer better economic and environmental prospects than similar carbon dioxide (CO2) processes. Dr. Yuli Shan from the University of Birmingham emphasized the importance of managing NOx emissions, especially in rapidly urbanizing areas in the global south, where urban renewal and modernization are causing increased atmospheric pollution. He noted that global NOx emissions nearly doubled from 70 Mt to 120 Mt between 1970 and 2018.
Ms. Ning Zhang from the Leibniz Institute of Ecological Urban & Regional Development highlighted the potential of nitrogenated concrete to capture NOx, which could be economically beneficial and reduce industrial NOx pollution in emerging industrial regions. The study points to China, Europe, and the United States as key players with the capacity to contribute significantly to this effort, promoting circular economies and addressing atmospheric environmental concerns.
The researchers recommend establishing an emissions trading system similar to the one for CO2 to better quantify and acknowledge the benefits of NOx sequestration. Despite the potential environmental and economic advantages, practical challenges remain, particularly in transporting large volumes of materials and gases. To optimize logistics and enhance feasibility, experts suggest using established industrial and commercial concrete carbonation systems for concrete nitrogenation.