Study on Long-term Effect of Oxytetracycline on ANAMMOX Nitrogen Removal Performance in the Treatment of Salt-containing Wastewater

The effects of oxytetracycline on anaerobic ammonium oxidation (ANAMMOX) were analyzed in this study. Meanwhile, the change of specific ANAMMOX activity (SAA) and the content of heme c were also revealed. The performance of ANAMMOX reactor decreased gradually when the increase of OTC concentration from 2mg/L to 10mg/L under 10‰ salinity. The nitrogen removal performance almost collapsed until the elevation to 10 mg/L OTC, observed with a huge decrease of SAA of 77.71% and heme c content of 88.04%. After no addition of OTC into the ANAMMOX reactor, the system performance recovered within 20 days. At the end of this phase, NH4+-N was completely removed, NO2--N was removed above 99%, and total nitrogen removal efficiency recovered to 85.33%.