Simultaneous anammox-denitrification process and its emerging extensions

Simultaneous anaerobic ammonium oxidation (Anammox) and Denitrification (called SAD) holds significant promise for removing nitrogen and organic matter from wastewater. Previous studies have demonstrated the ability of SAD process and its emerging extensions, such as Simultaneous Nitritation, Anammox and Denitrification (SNAD) and simultaneous Anammox, Denitrification and Sludge Fermentation (ADSF), to integrate the nitrogen cycle with the carbon cycle. This study systematically reviews three types of SAD process, in terms of their microbial groups and their relationships. Anammox bacteria and denitrifiers commonly experience a symbiotic and/or competitive relationship when treating real wastewater. Biofilm formation and organic matter limitations are considered the most critical conditions for the co-existence of anammox and denitrification. This study also provides an overview of the research and development of the state-of-the-art processes based on SAD. We conclude that, while the optimized performance of SAD process and its extensions have been largely recognized, there is a need to better understand the mechanics, particularly with respect to a kinetic and stoichiometric analysis.

Automated summary

The SAD process and its extensions show promise in removing nitrogen and organic matter from wastewater, but understanding the relationship between Anammox and denitrifiers, as well as biofilm formation and organic matter limitations, is crucial for their co-existence. Further research is needed to better comprehend the mechanics, particularly through kinetic and stoichiometric analysis.