Impact of Influent Composition and Operating Conditions on Carbon and Nitrogen Removal from Urban Wastewater in a Continuous-Upflow (Micro)Aerobic Granular Sludge Blanket Reactor

Aerobic granular sludge is an interesting alternative to the conventional activated (CAS) system and modified-Ludzack–Ettinger (MLE) process for biological wastewater treatment, as it allows a more cost-effective simultaneous removal of carbon (C) nitrogen (N) compounds in single stage. In this study, (micro)aerobic C N from synthetic urban was investigated continuous-double-column-upflow aerobic blanket (UAGSB) system. The UAGSB reactor operated under different dissolved oxygen (DO) ranges (0.01–6.00 mg∙L−1), feed C/N ratios (4.7–13.6), hydraulic retention times (HRTs) (6–24 h). At DO range 0.01–0.30 mg∙L−1, ratio 13.6, HRT 24 h, achieved highest chemical demand (COD), N-NH4+, total inorganic (TIN) efficiencies 86, 99, 84%, respectively. A preliminary assessment energy economic savings associated with also carried out. impact capital operating costs mainly related consumption aeration taken into account. reveals that expenses would result cost around 14 7%, respectively, compared MLE