NO2^-浓度对反硝化聚磷颗粒污泥缺氧吸磷的影响

Effect of NO_2^- on phosphorous uptake of the SBR denitrifying granular sludge

以经过NO3-诱导的反硝化聚磷颗粒污泥为对象,研究了NO2-浓度对反硝化聚磷的影响。结果表明,反硝化聚磷过程中,当NO2-≤6.0mg/L时,反硝化聚磷颗粒污泥可利用NO2-为电子受体进行反硝化聚磷,消耗单位N的最大聚磷量为3.45mg;NO2-≥10.0mg/L时,对颗粒污泥反硝化聚磷产生较强抑制,消耗单位N的聚磷量仅为1.00mg;NO2-对反硝化聚磷的抑制主要与HNO2有关,HNO2对颗粒污泥反硝化聚磷的抑制阈值为0.0008mg/L。

Batch phosphorous （P） uptake experiments were performed to determine the effect of nitrite concentration （NO2^-） on P uptake of the denitrifying granular sludge of the A2/O SBR employed for treating a synthetic feed, which was supplemented with increasing amount of nitrate after the granular sludge was formed. The SBR granular sludge was capable of using nitrate as the electron acceptor to remove about 78.9% of the total P removed and that up to 6.0 mg/L of NO2^- was accumulated during denitrification. The P uptake test results show that the denitrifying granular sludge used nitrite as the electron acceptor to remove P. At a low initial NO2^- of ≤6.0 mg/L, the P uptake was fast as evidenced by the high P removal rate of 3.45 mg N consumed, which was much faster than the P removal in the SBR using NO3^- as the electron acceptor （1.58 mg N consumed） ; however, at a high initial NO; of 10.0 mg/L, the P uptake was inhibited to result in a low removal rate of 1.00 mg N consumed.