不同电子受体对反硝化除磷菌缺氧吸磷的影响

利用厌氧/缺氧/好氧交替运行模式培养和富集反硝化除磷污泥,通过在缺氧段分别投加不同浓度的硝酸盐和亚硝酸盐,进行了反硝化除磷菌（DPB）在不同电子受体条件下的缺氧吸磷试验.结果表明,在保证有足够的硝酸盐电子受体的情况下,DPB的缺氧吸磷速率几乎不受硝酸盐浓度的影响,在试验条件下,缺氧阶段每消耗1 mg NO^-₃-N吸收约1 mg PO^３－_４-P;在一定浓度条件下,亚硝酸盐能够作为电子受体参与DPB反硝化吸磷,DPB在较低亚硝酸盐浓度（NO^-₂-N在5～20 mg/L范围）下的缺氧吸磷速率高于以硝酸盐为电子受体时的缺氧吸磷速率,并且缺氧吸磷速率在这个范围内随NO^-₂-N浓度的升高而降低;亚硝酸盐对DPB缺氧吸磷的抑制程度随其浓度的增加而增强,当NO^-₂-N≥35 mg/L时,DPB的缺氧吸磷反应几乎完全停止.

Effect of Electron Acceptors on Anoxic Phosphorus Uptake of DPB

The test of anoxic phosphate uptake of denitrifying phosphorous removal bacteria (DPB) which was cultivated during the anaerobic/anoxic/aerobic processes was conducted at the various situations of electron acceptors. The various concentrations of nitrate or nitrite were added during the anoxic stage respectively. The conclusions stated that the anoxic phosphate uptake of DPB was rarely influenced by the concentration of nitrate with the adequate nitrate as electron acceptors. It takes 1 mg PO43--P when the consumption of NO3--N is 1 mg. The nitrite could be regarded as the electron acceptor to participate into the activities of denitrifying phosphorous removal. Compared with the nitrate, the phosphorous uptake rate of DPB with nitrite was rather higher at a low concentration (NO2--N with the concentration range of 5~20mg/L). Furthermore, the rate of anoxic phosphorous uptake was increased with the decreased concentration of NO2--N. The restraining effects related to the anoxic phosphors uptake of DPB was increased as the increase of nitrite concentration. Hence, the anoxic phosphorous uptake of DPB was entirely inhibited when the concentration of NO2--N was higher than 35 mg/L.