Path to zero emission of nitrous oxide in sewage treatment: is nitrification controllable or avoidable?

Abstract

Amid growing concerns over climate change, the need to reduce nitrous oxide (N₂O) emissions from sewage treatment is more urgent than ever. Sewage treatment plants are significant sources of N₂O due to its production as an intermediate in nitrification and its release into the air during aeration. Effective management of the nitrification process is therefore vital for controlling or eliminating these emissions. Despite substantial efforts to quantify and understand N₂O emissions from sewage treatment, success in reducing them has been limited. This review discusses and proposes promising solutions for reducing N₂O emissions in sewage treatment, evaluates the potential of various strategies, and identifies ways to accelerate their development and implementation.