Startup of pilot-scale single-stage nitrogen removal using anammox and partial nitritation (SNAP) reactor for waste brine treatment using marine anammox bacteria

Emerging biotechnological applications of anaerobic ammonium oxidation

Anaerobic ammonium oxidation (anammox) is an energy-efficient method for nitrogen removal that opens the possibility for energy-neutral wastewater treatment. Research on anammox over the past decade has primarily focused on its implementation in domestic wastewater treatment. However, emerging studies are now expanding its use to novel biotechnological applications and wastewater treatment processes. This review highlights recent advances in the anammox field that aim to overcome conventional bottlenecks, and explores novel and niche-specific applications of the anammox process. Despite the promising results and potential of these advances, challenges persist for their real-world implementation. This underscores the need for a transition from laboratory achievements to practical, scalable solutions for wastewater treatment which mark the next crucial phase in the evolution of anammox research.

On anammox activity at low temperature: effect of ladderane composition and process conditions

The application of partial nitritation-anammox (PN/A) under mainstream conditions can enable substantial cost savings at wastewater treatment plants (WWTPs), but how process conditions and cell physiology affect anammox performance at psychrophilic temperatures below 15 °C remains poorly understood. We tested 14 anammox communities, including 8 from globally-installed PN/A processes, for (i) specific activity at 10-30 °C, (ii) composition of membrane lipids, and (iii) microbial community structure. We observed that membrane composition and cultivation temperature were closely related to the activity of anammox biomasses. The size of ladderane lipids and the content of bacteriohopanoids were key physiological components related to anammox performance at low temperatures. We also indicate that the adaptation of mesophilic cultures to psychrophilic regime necessitates months, but in some cases can take up to 5 years. Interestingly, biomass enriched in the marine genus "Candidatus Scalindua" displayed outstanding potential for nitrogen removal from cold streams. Collectively, our comprehensive study provides essential knowledge of cold adaptation mechanism, will enable more accurate modelling and suggests highly promising target anammox genera for inoculation and set-up of anammox reactors, in particular for mainstream WWTPs.