Abstract
The biocidal effects of free nitrous acid (FNA) have found applications in multiple units in an urban wastewater system, including sewer networks, wastewater treatment processes, and sludge treatment processes. However, these applications are associated with chemical costs as both nitrite and acid are needed to produce FNA at the required levels. The recent discovery of novel acid-tolerant ammonia oxidizers offers the possibility to produce FNA from domestic wastewater, enabling the development of next-generation FNA-based technologies capable of achieving self-sustaining FNA production. In this study, we focus on the concept of in situ FNA generation facilitated by acid-tolerant ammonia oxidizers and highlight the multiple benefits it creates, after a brief review of the historical development of FNA-based technologies. We will discuss how wastewater systems can be made more energy-efficient and sustainable by leveraging the potential of acid-tolerant ammonia oxidizers.
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Acknowledgements
Dr. Zhiqiang Zuo acknowledges the International Postdoctoral Exchange Fellowship Program (China) and the National Natural Science Foundation of China (No. 52300188). Dr. Min Zheng is the recipient of an Australian Research Council (ARC) Industry Fellowship (IE230100245). Dr. Tao Liu is the recipient of an ARC DECRA Fellowship (DE220101310). Prof. Zhiguo Yuan is Global STEM Scholar funded by the Government of the Hong Kong Special Administrative Region, China.
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Conflict of Interest The authors Yongzheng Peng and Zhiguo Yuan are Members of Advisory Board of Frontiers of Environmental Science & Engineering. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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Highlights
• The historical development of free nitrous acid (FNA) technologies is reviewed.
• The roles of novel acid-tolerant ammonia oxidizers are highlighted.
• Acid-tolerant ammonia oxidizers can self-sustain high-level FNA production.
• The next-generation in situ FNA-based technologies are discussed.
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Zuo, Z., Zheng, M., Liu, T. et al. New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management. Front. Environ. Sci. Eng. 18, 26 (2024). https://doi.org/10.1007/s11783-024-1786-5
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DOI: https://doi.org/10.1007/s11783-024-1786-5