Wastewater treatment is evolving, with innovation at its core. Anammox bacteria are transforming nitrogen removal, slashing energy use and carbon emissions while enhancing efficiency.
As climate pressures mount, one leading wastewater expert says adopting advanced biological processes like these is key to sustainable water management and a net-zero future.
Veolia Water Technologies Senior Process Specialist R&D for AnoxKaldnes, Magnus Christensson said continuing to strive for wastewater treatment improvement and resource recovery is a necessity in the face of climate change, population growth and urbanisation.
“We live in a world where rising global temperatures, water scarcity, eutrophication, and increasing urbanisation present significant challenges,” he said.
“To address these, it is essential to view wastewater as a resource that is capable of yielding valuable by-products through reuse. This requires a new suite of innovative technologies and approaches to treatment.
“Biological processes offer nature-based, efficient, and remarkably intelligent solutions. The key lies in understanding and harnessing these processes effectively.”
Christensson said one of the most fascinating biological treatments increasingly deployed today involves a group of bacteria known as anammox bacteria.
“These bacteria offer a unique shortcut in the traditional nitrogen removal pathway, enabling significant reductions in both oxygen and carbon requirements,” he said.
“While this might seem almost too good to be true, it is a reality. However, a key challenge with anammox bacteria is their slow growth rate, which requires wastewater treatment processes to be highly robust.
“To address this, Veolia has developed the Anita™ Mox process, where anammox bacteria grow as a biofilm on the protected surfaces of small carriers suspended in a process tank.
“This setup, known as a Moving Bed Biofilm Reactor (MBBR), ensures that the bacteria are safely retained by simple outlet screens, providing the robustness necessary for reliable operation.”
Biological wastewater treatment methods offer considerable environmental benefits in comparison to traditional methods, particularly in reducing energy and resource consumption, Christensson said.
"Because they require less aeration and carbon for nitrogen removal, these methods lead to direct operational savings. One optimal application for this approach is the sidestream treatment of rejected water from digested sludge dewatering,” he said.
“This water has high nitrogen content, low available carbon, and limited alkalinity. By treating the sidestream, the nitrogen load on the main treatment process is reduced, making it easier to meet effluent quality standards.
“Additionally, these methods lower the plant’s overall carbon footprint, which is critical for helping utilities achieve their net-zero emissions targets.”
While hugely beneficial, there have been some hurdles involved in adopting biological wastewater treatment innovations, Christensson said, but recent research and development initiatives have found new paths forward.
“Historically, one of the challenges in implementing anammox technology in Australia has been the slow initial growth of anammox bacteria, which require a reliable source of seed material,” he said.
“Importing this seed material from overseas was not feasible due to regulatory constraints. But this challenge has now been overcome through a collaborative effort between Veolia, the University of Queensland and Urban Utilities.
“Together, they successfully built up seed material in stages for Australia’s first full-scale Anita™ Mox plant at the Luggage Point facility in Brisbane.
“This plant now serves as a “bio-farm”, providing the seed material required for future Anita™ Mox installations across the country. This breakthrough presents a significant opportunity for wastewater operators to adopt this advanced technology more readily.”
In light of net zero requirements, Christensson said that a major driver of innovation in biological treatment technologies will be the need to reduce greenhouse gas emissions over the next decade.
“The Anita™ Mox process is well-suited to this goal, thanks to its ability to save both oxygen and carbon,” he said.
“This focus aligns well with Veolia’s core mission, centred on ecological transformation. This vision is not only about addressing environmental challenges but also about creating a future where resources are preserved.
“Our GreenUp strategic plan brings this to life, delivering and investing in solutions that depollute, decarbonise, and regenerate resources to address climate challenges.”
A particularly critical focus for future technologies will be mitigating the emission of nitrous oxide (N₂O), a potent greenhouse gas that can be generated during biological nitrogen removal,” Christensson said.
“To address this, the pairing of these technologies with optimised, real-time control systems will be essential. Veolia has developed Hubgrade, a cloud-based system that enhances process stability and minimises N₂O emissions,” he said.
“With these advanced tools and the dedication of industry professionals, researchers, and consultants, the outlook for Australia’s wastewater sector is highly promising.
“We are truly at the beginning of an exciting and sustainable journey.”
Interested in learning more about advanced and innovative wastewater treatment processes? Check out the Excellence in Operations + Wastewater Optimisation stream at Ozwater’25.