This lecture covers the process of nitrogen removal in wastewater treatment plants through the combination of nitritation and ANAMMOX, exploring the key figures of WWTPs based on SBR technology, the savings due to the SHARON process, and the proposed mechanisms of anaerobic ammonium oxidation. It also discusses the challenges faced in inhibiting nitrite oxidizing bacteria and controlling pH, as well as various process options for efficient nitrogen removal. The lecture delves into the benefits of ANAMMOX, such as increased BOD removal and energy consumption considerations, providing insights into the design and operation of WWT plants for optimal nitrogen removal.