Oxygen-limited autotrophic nitrification/denitrification (OLAND) is a microbiological process to remove nitrogen from wastewater by partial nitritation and anammox. The biomass structure is determined by extracellular polymeric substances (EPS). This research wants (i) to determine which bacteria produce which EPS, (ii) to elucidate the influence of EPS quantity and composition on the process, and (iii) to reach an optimal EPS production.