Impact of Saddle-Chips biocarrier on treating mariculture wastewater by moving bed biofilm reactor (MBBR): Mechanism and kinetic study

Abstract Packing carrier is a key factor for moving bed biofilm reactors (MBBRs) treating ammonia polluted wastewater such as in mariculture aquaculture but lacks sufficient research. In this study, a new type of biocarrier, Saddle-Chips (SC), was applied for treating mariculture wastewater (30‰ salinity) and compared with commonly used Kaldnes-5 (K5-biocarrier), using lab-scale MBBRs. The effects of ammonia concentrations, hydraulic retention times (HRTs), filling ratios (FRs), and ammonia shock-loading on MBBRs’ performances were examined. In the results, the new SC-biocarrier showed a slightly higher NH 4 + − N removal efficiency (NRE) than K5 (p > 0.05). Higher HRTs (24 and 12 h) yielded higher nutrients removal efficiency despite low biomass productivities initially. Moreover, 60% FR showed higher nutrients removal due to higher biomass than 30% FR (p  NH 4 + − N concentrations and HRTs with high precision (R2 > 0.98). Overall, the nitrogenous pollutants’ high removal efficacy, biopolymer release capability, and excellent hydrodynamics revealed by the SC-biocarrier highlight its large-scale suitability in treating mariculture wastewater and other wastewater types.