Evaluation of the efficacy and regulation measures of the anammox process under salty conditions

The present study aimed to achieve a better understanding of the performances of anaerobic ammonium oxidation (anammox) reactors using different strategies to manage high salt conditions. Batch assays were conducted to ascertain the effects of ion species, and the results demonstrated the different effects on the specific anammox activity. Osmotic pressure was another determining factor with a 50% inhibitory level of 1.4 MPa. Self-adaptation strategies were conducted by running R-1 (gradual adaptation) and R-2 (rapid adaptation), and the nitrogen removal rates were 3.71 +/- 0.63 kg N m(-3) d(-1) (111) and 3.48 +/- 0.51 kg N m(-3) d(-1) (R-2) below 15 g NaCl L-1. Additionally, the NRR decreased significantly when the salinity was increased (more severe in R-2). Furthermore, the enhanced adaptation tests confirmed that extra biomass addition (EBA) in R-2 was effective to resist the salinity stress, whereas the effectiveness of glycine betaine addition (GBA) in R-3 was dubious. (C) 2014 Elsevier B.V. All rights reserved.