Ecofriendly Anaerobic Ammonium Oxidation System: Optimum Operation and Inhibition Control Strategies for Enhanced Nitrogen Removal

In practice, the complete autotrophic nitrogen removal or partial-nitritation (PN) and anaerobic ammonium oxidation (ANAMMOX) process (PN/A) has gained immense popularity and widespread application owing to its low operational cost and better treatment possibilities. However, ANAMMOX-based systems are inhibited by numerous factors that pose enormous challenge to the success of this technology. Hence, in lieu of finding optimum operational strategies, a PN/A sequencing batch reactor for treating high-strength ammonia wastewater obtained from an anaerobic digester was evaluated for 400 days. The impact of processing unit cycle strategies on process performance was evaluated with the amalgamation of intermittent feeding and aeration. The ecofriendly and eco-efficient system, adopted in this study, ensured enhanced cost-effective nitrogen removal along with reduction in greenhouse gas (GHG) emissions underlying stringent regulation. Nitrogen removal rate of 81% along with 68% reduction in GHG emissions compared to the conventional nitrification/denitrification system (29% lower than the last reported ANAMMOX system) was successfully achieved. The key concerns in negating the impacts of ANAMMOX inhibition caused by the seven most influential parameters/mechanisms are also addressed.