Effect of Shock Loads on the Process Stability and Behavior of an Anammox Hybrid Reactor

Abstract

The process stability of laboratory scale anammox hybrid reactor (AHR) was studied at different substrate and hydraulic shock loadings. The substrate shock load (SSL) was given by increasing the nitrogen concentration from 500–1750 mg/L, while the hydraulic shock loads (HSLs) were given by increasing the flow rates to 1.5‐, 2.5‐, and 3.5‐fold, respectively. Performance analysis of AHR dictated that the reactor was relatively more tolerant to HSLs but showed increased sensitivity to SSLs. Polynomial model and Gaussian model were applied to simulate the effect of overloads on the anammox bioreactor. Higher values of sensitivity index (1.96–12.86) and response factor (95.36–152.44) indicated higher degree of perturbations during SSLs than hydraulic shocks. This may be attributed to lower recovery rate (3.3–6.2 mg/mg h) during substrate shocks than HSLs. The modified Stover‐Kincannon model predicted the recovery potential of AHR with fair degree of accuracy.