Novel insights into Anammox-based processes: A critical review

Anammox has been globally accepted as the most promising sewage treatment process. However, the full-scale application of theanammox process islimited because anammox bacteria are easily susceptible to environmental conditions and deficient in nitrite supply. Presently, nitritation and denitratation are generally considered the two-ideal nitrite-generating pathways for anammox, while operating stability and optimizing regulation have been outstanding issues. Therefore, a comprehensive summary of the potential ventures and control procedures to overcome these challenges was needed. To this end, this study firstly reviews the valuable new outcomes of the pure anammox process, including the implemented sludge morphology, various wastewater characteristics, and metabolic regulation measures to improve anammox activity. Then, the key advances in nitritation and denitratation processes which can take a couple with anammox for the advanced nitrogen removal, are well presented. Finally, a novel proposed processes that develops one-step simultaneous partial nitritation, denitratation, and anammox (SPNDA) and simultaneous partial nitritation, anammox and denitrification (SNAD)for the ammonium and nitrate wastewater treatment and its feasibility in energy-efficient nitrogen removal was analyzed. This review offers a more cost-effective and environment-sustainable perspective for future engineering applications of anammox..