Next-Generation Wastewater Solutions: Utilizing Acid-Resistant Microbes for Improved Treatment Efficiency

Fig.1 Graphic abstract.

Fig.2 Potential applications of FNA produced in situ by acid-tolerant AOB to sewage and sludge treatment.

Fig.3 Wider applications of FNA produced in situ for sustainable wastewater management.

Newswise — Free nitrous acid (FNA) is known for its capacity to inhibit various microorganisms in wastewater systems, significantly benefiting treatment process management. Initially deemed problematic due to its potential adverse effects on treatment, FNA is now employed to enhance wastewater management by mitigating odors, emissions, and harmful bacteria. Nonetheless, the traditional production of FNA is expensive, dependent on substantial chemical inputs. Recent advancements strive to optimize and render its production more economical.

A groundbreaking perspectives, published in Frontiers of Environmental Science & Engineering on 05 December 2023, introduces a novel approach for sustainable wastewater management. Leveraging the unique properties of FNA, researchers aim to create more energy-efficient and sustainable wastewater systems.

The study introduces an innovative approach in wastewater management by exploring the potential of acid-tolerant ammonia oxidizers (AOB) to produce FNA directly from domestic wastewater. This method utilizes the biocidal effects of FNA, traditionally limited by chemical costs, to improve various wastewater treatment processes. Researchers have identified acid-tolerant AOBs like Nitrosospira, Nitrosococcus, and Candidatus Nitrosoglobus, which flourish in acidic conditions that usually inhibit standard AOBs. The resilience of these organisms to strong FNA enables in situ generation of FNA, eliminating the need for external nitrite and acid, thus reducing operational costs and chemical usage. The application of these acid-tolerant AOBs effectively lowers wastewater pH and functions optimally in acidic conditions, offering a more sustainable and energy-efficient wastewater management system. This innovative approach aims to leverage the natural abilities of these organisms to boost the efficiency and sustainability of wastewater treatment, marking a significant progression in environmental engineering.

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.

Researchers state, "This study not only redefines the efficiency and sustainability of wastewater management but also demonstrates the remarkable adaptability and resilience of novel microbiological processes in environmental engineering."
Implementing acid-tolerant AOB in wastewater systems has demonstrated the potential for energy self-sufficiency and enhanced sustainability. By effectively reducing wastewater pH and operating optimally in acidic conditions, these AOBs can significantly enhance the efficiency and effectiveness of wastewater management without requiring external acids. This approach not only offers broader possibilities for enhancing wastewater management but also signifies a considerable advancement towards environmentally sustainable practices.

References
Funding information
The International Postdoctoral Exchange Fellowship Program (China);
The National Natural Science Foundation of China (52300188);
The recipient of an Australian Research Council (ARC) Industry Fellowship (IE230100245);
The recipient of an ARC DECRA Fellowship (DE220101310);
Global STEM Scholar funded by the Government of the Hong Kong Special Administrative Region, China.
DOI: 10.1007/s11783-024-1786-5
Original URL: https://doi.org/10.1007/s11783-024-1786-5
About Frontiers of Environmental Science & Engineering
Frontiers of Environmental Science & Engineering (FESE) is the leading edge forum for peer-reviewed original submissions in English on all main branches of environmental disciplines. FESE welcomes original research papers, review articles, short communications, and views & comments. All the papers will be published within 6 months since they are submitted. The Editors-in-Chief are Academician Jiuhui Qu from Tsinghua University, and Prof. John C. Crittenden from Georgia Institute of Technology, USA. The journal has been indexed by almost all the authoritative databases such as SCI, Ei, INSPEC, SCOPUS, CSCD, etc.