Nitrogen removal through "Candidatus Brocadia sinica" treating high-salinity and low-temperature wastewater with glycine addition: Enhanced performance and kinetics

Freshwater-derived anaerobic ammonia oxidation (anammox) bacteria ("Candidatus Brocadia sinica") were investigated to remove nitrogen from high-salinity and low-temperature wastewater with glycine addition. The reactor was operated at 15 +/- 0.5 degrees C with influent pH of 7.5 +/- 0.1. When glycine were 0.2, 0.4, and 0.6 mM, respectively, nitrite removal rate (NRR) increased by 27.7%, 47.3%, and 70.4% accordingly. Optimal ammonia removal rate (0.32 kg/(m(3).d)) and NRR (0.45 kg/(m(3).d)) were achieved at 0.8mM glycine. Effect resulting from glycine on nitrite reductase was higher than hydrazine synthase. Moreover,. Delta NO2--N/Delta NH4+-N increased with glycine addition while Delta NO3--N/Delta NH4+-N first increased and then decreased. The remodified Logistic model and modified Boltzmann model were appropriate to describe nitrogen removal with glycine addition. Kinetic parameter lambda achieved through the remodified Logistic model revealed that "Candidatus Brocadia sinica" had a shorter lag phase than that of marine anammox bacteria.