Erdirencelebi, DilekKoyuncu, Serdar2020-03-262020-03-2620180733-93721943-7870https://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0001317https://hdl.handle.net/20.500.12395/36824Optimization of total nitrogen (TN) removal via the nitrite path was studied at a sequential batch reactor (SBR) from anaerobic reject water (ARW) with a content of slowly degrading organic matter of lipid structure. The study was conducted as a pilot-scale side-line treatment in a large-scale municipal and industrial wastewater treatment plant (WWTP). Operational mode was modified based on feeding pattern, sequence order, phase duration, and number to maximize TN removal and minimize lipid-related interferences. Ammonium loading rate (ALR) proceeded at 0.2-0.7kgN/m3day and the optimum range was determined for maximum TN removal. An insufficient HCO3-/N ratio was further lowered by volatile fatty acids (VFA) production via beta-oxidation of long-chain fatty acids (LCFA) during nitritation. The organic content of ARW and VFA showed a low degradability by denitrifying bacteria and limited TN removal. Modifications in the operational mode increased ammonium and nitrite removal and reduced toxic-free VFA and nitrous acid (FNA) with increased anoxic and aerobic denitritation. Ammonium nitrogen at 180-478mgN/L was reduced to approximately 20mgN/L in all effluents and TN removal was achieved at 84-86%. Temperature sensitivity was higher for denitritation than nitritation. (C) 2017 American Society of Civil Engineers.en10.1061/(ASCE)EE.1943-7870.0001317info:eu-repo/semantics/closedAccessWastewaterNitrogen removalLipidOxidationOperationSequential batch reactorArticle1442Q2WOS:000418186700016Q3