Veolia's 4-Step Methodology to N2O Reduction Results in 78% Emissions Decrease at Bjergmarken WWTP

As the wastewater industry faces a growing need to address climate change, nitrous oxide (N2O) emissions from treatment plants have emerged as a critical concern. N2O, a potent greenhouse gas with a global warming potential 273 times that of CO2, poses a significant challenge to the sector’s climate mitigation efforts as it could represent even more than 50% of the entire GHGs of a WWTP.

This presentation focuses on one of Veolia’s most recent cases, where we present a long period without mitigation (2023) and more than a full year of measure with mitigation (2024). Veolia has developed a 4-steps methodology to mitigate N2O emissions with a holistic approach combining real-time data management, process expertise, and digital twin technology. By providing the successful example of Bjergmarken’s approach, other WWTPs will be able to replicate their success.

This methodology consists of four key steps: Measure, Understand, Strategize, and Empower.
⇒ Measure emissions: First, we employ advanced monitoring systems to accurately measure N2O emissions across various treatment processes. This continuous, real-time data collection provides a comprehensive picture of emission patterns and hotspots within the plant.
⇒ Understand the process: Next, we understand the complex mechanisms behind N2O formation and emission through in-depth analysis of the collected data. This step involves identifying the key factors influencing N2O production, such as dissolved oxygen levels, nitrite concentrations, and even microbial community dynamics.
⇒ Develop a strategy: The “strategize" phase leverages Veolia’s extensive process expertise to develop effective mitigation scenarios. Our team of experienced engineers and scientists analyses the plant-specific data and applies industry best practices to formulate tailored, cost-effective mitigation plans. These strategies balance emission reduction with other operational priorities, ensuring optimal overall plant performance.
⇒ Empower operators: Finally, we empower plant operators by integrating digital twin technology into their daily operations. It provides real-time insights and control, enabling operators to make informed decisions that optimize plant performance while minimizing N2O emissions. The digital twin acts as a powerful tool for continuous improvement, adapting to changing conditions and evolving regulatory requirements.

This 4-steps approach represents a significant advancement in sustainable wastewater management, addressing the critical need for climate change mitigation in the sector.

By sharing the experiences and insights from the Bjergmarken WWTP case study, we aim to contribute to the industry’s collective knowledge and inspire innovative solutions across the field. This methodology offers a practical framework for tackling the complex challenge of N2O emissions. We believe that by working together and openly sharing successes and lessons learned, the wastewater treatment community can make significant strides in reducing our environmental impact, improving operational efficiency, and building a more sustainable water industry for the future.