Influence of the acetate concentration on the recovery time of a perturbed anaerobic digester

Summary Imbalance in a fluidized bed reactor was simulated by injecting pure or mixed acetate and propionate salts into the digester. For acetate levels higher than 13–15 mM, propionate degradation was inhibited. In these cases, the time required by the system to reduce the propionate concentration up to steady-state values was approximately 60–70 % higher than the recovery time found in the cases in which this inhibition was not present.