Designs of monitoring locations and case studies
Sarah Aucote, Ilda Clos, Floris de Heer, Carlos Domingo-Felez, Haoran Duan, John Duong, Ahlem Filali, Wenzel Gruber, Sabrina Guérin-Rechdaoui, David Hume, Clare Idriss, Jeremy Kraemer, Rania Krimou, Pui Tan Li, Rhodri Lucas, Sela Maka, Ruth McConnell, Kenneth McGibbon, Niloshree Mukherjee, Sanjeev Oberoi, Liam Owen, Lizanne Pharand, Johann Poinapen, Petra Reeve, Ellie Russell, Siddharth Seshan, Magi Stoyanova, Frank van de Grootevheen, Ellen van Voorthuizen, Peter Wardrop, Leon Wu, Liu Ye, Xueying Zhang, Elliot Cichero, Marybeth Dela Cruz, Kenny Liew, Jason Dwyer, Wakib KhanSummary
This chapter presents a practical, top-down three-level framework (L1–L3) for selecting representative nitrous oxide monitoring locations in uncovered wastewater treatment plants. The approach systematically distinguishes sludge systems (L1), parallel versus non-parallel bioreactors (L2), and spatial heterogeneity within reactors (L3), supported by a decision-making tree and equations for plant-wide emission aggregation. The methodology is demonstrated using 19 full-scale international case studies, covering 12 typical configurations applied in practice: conventional activated sludge, step-feed, modified Ludzack Ettinger, Bardenpho, oxidation ditch, sequencing batch reactors (including aerobic granular sludge), membrane bioreactors/membrane aerated biofilm reactors, Modified University of Cape Town (MUCT), integrated fixed-film activated sludge, biofilters (biological aerated filter/Biostyr®), side-stream treatment systems, and other hybrid or site-specific designs. These cases illustrate how process configuration, aeration control, and spatial variability govern monitoring requirements and data representativeness. Practical lessons learned during implementation of monitoring campaigns are also highlighted across multiple case studies.