土霉素对厌氧氨氧化颗粒污泥脱氮性能的影响

Inhibitory Effect of Oxytetracycline on Nitrogen Removal by Anammox Granules

通过批次试验和连续流试验研究了土霉素对厌氧氨氧化颗粒污泥脱氮性能的影响。厌氧氨氧化颗粒污泥反应器(UASB)进水NH_4^+-N浓度为40~50 mg/L,NO_2^--N浓度为55~65mg/L,温度控制为30℃,HRT控制为1.6 h。经过60 d运行,反应器的厌氧氨氧化脱氮性能良好,出水NH_4^+-N和NO_2^--N浓度分别为3.1和6.3 mg/L,对NH_4^+-N、NO_2^--N和TIN的去除率分别为91.2%、93.4%和75.2%。在土霉素对厌氧氨氧化颗粒污泥反应器的长期抑制试验中,颗粒污泥对土霉素具有一定的耐受能力,当进水中的土霉素浓度为10 mg/L时,反应器对NH_4^+-N和NO_2^--N的去除率分别为70.7%和70.8%;当进水中的土霉素为20 mg/L时,反应器对NH_4^+-N和NO_2^--N的去除率分别降低至16.8%和18.1%。与长期抑制试验相比,批次试验中土霉素对颗粒污泥厌氧氨氧化活性的抑制作用较小,土霉素浓度为50、100、150、200和400 mg/L时,对TIN的去除速率分别为0.498、0.480、0.439、0.326和0.120 kg N/(kg VSS·d)。

The short- and long-term effects of oxytetracycline （OTC） on nitrogen removal performance of anaerobic ammonium oxidation （Anammox） granules were investigated in batch tests and continuous flow reactor, respectively. As for the Anammox granular reactor （ UASB）, the influent NH4^＋ - N and NO2^- -N concentrations were 40 -50 mg/L and 55 -65 mg/L, respectively. Besides, the temperature and hydraulic retention time （HRT） were controlled at 30 ℃ and 1.6 h, respectively. As a result, the Anammox granular reactor performed good nitrogen removal performance after being inoculated with Anammox granules for 60 days. The effluent NH4 ^＋- N and NO2^- - N concentrations were 3.1 mg/L and 6.3 mg/L. The NH4^＋ -N , NO2^- -N and total inorganic nitrogen （TIN） removal efficiencies were 91.2%, 93.4% and 75.2%, respectively. During the long-term experiments, the nitrogen removal performance of the Anammox granules was slightly inhibited with the influent OTC concentration of 10 mg/L. The average NH4^＋ - N and NO2^- - N removal rates of the Anammox granular reactor decreased to 70.7% and 70.8%, respectively. Moreover, with the influent OTC concentration of 20 mg/L, the nitrogen removal performance of the Anammox granules was largely inhibited. The average NH4^＋ - N and NO2^- - N removal rates of the Anammox granular reactor decreased to 16.8% and 18.1%, respectively. Compared with the long-term experiments, the inhibition of OTC on the Anammox granules in batch tests was relatively lower. The TIN removal rates of the anammox granules were 0. 498, 0.480, 0. 439, 0.326 and 0. 120 kgN/ （kgVSS · d） with the initial OTC concentrations of 50, 100, 150, 200 and 400 rag/L, respectively.