Performance and hydrodynamic features of a staged up-flow ANAMMOX sludge bed (SUASB) reactor

Abstract

• The staged ANAMMOX reactor (SUASB) was investigated systematically. • The application of the kinetic model was validated. • The robust performance of the SUASB was demonstrated. • A maximum NRR of 6.04 kg N m −3 d −1 and NLR of 6.88 kg N m −3 d −1 were achieved. • The hydrodynamic type of the SUASB reactor was investigated. The performance and hydrodynamic features of a staged up-flow ANAMMOX (anaerobic ammonium oxidation) sludge bed (SUASB) reactor was evaluated. When the reactor was at steady-state conditions, the nitrogen loading rate (NLR) and nitrogen removal rate (NRR) were 5.63 and 4.82 kg N m −3 d −1 , respectively. The reactor could withstand a 1.5-fold substrate or hydraulic shock. The modified Stover–Kincannon model was used for the kinetic analysis, and the saturation value ( K B ) and maximum total substrate utilization rate ( U max ) were 14.5 and 14.8 kg N m −3 d −1 , respectively. Moreover, the C ( t )– Θ curve showed the existence of dead zones in the SUASB at the hydraulic retention times (HRTs) of 3 and 12 h, and the flow pattern performance of the SUASB fell between those of a continuous stirred tank reactor (CSTR) and a plug flow reactor (PFR).