缺氧-好氧移动床生物膜反应器处理低温生活污水效能

Efficiency of Anoxic-Oxic Moving-Bed Biofilm Reactor Treating Low Temperature Sewage

为解决冬季冰封期城市污水处理厂出水水质难于达标的问题,基于移动床生物膜反应器(MBBR)处理效率高及抗负荷能力强等特征,采用缺氧-好氧移动床生物膜反应器处理低温生活污水,重点考察了其对低温生活污水的处理效能及其影响因素.结果表明:在8℃的低温,好氧MBBR内悬浮型填料填充比为40%,水力停留时间为(HRT)6h,ρ(DO)为7～8mg/L的条件下,该工艺对CODCr和NH4+-N的去除效果最佳,二者的去除率分别达到88.70%和65.72%;当缺氧MBBR内悬浮型填料填充比为50%,内循环回流比为200%时,TN的去除率可达65.65%,此时,整体反应器对CODCr和NH4+-N的去除率分别为90.70%和71.65%.结果还表明,由常温转为低温环境后,缺氧-好氧MBBR的处理效率有所下降,但通过调整反应器内填料的填充比,ρ(DO)和HRT等参数,可保证对CODCr和NH4+-N的去除仍具有较好的效果.

It is difficult for effluent from municipal sewage plants to meet the water quality standard during icy periods in winter months. To resolve this problem, based on the characteristics of high treatment efficiency and anti-impulsion load of the moving-bed biofilm reactor （MBBR） , Auoxic-Oxic MBBR was used to treat sewage at low temperatures. The treatment efficiency of Anoxic-Oxic MBBR and the influencing factors were investigated under low temperature conditions. The experimental results showed that the removal efficiencies of CODCr and NH4^ ＋-N could reach 88.70% and 65.72% respectively under the following conditions： sewage temperature 8 ℃, filling ratio of suspended carriers in the oxie MBBR reactor 40% ,hydraulic retention time （HRT） 6 h and DO mass concentration 7- 8 mg/L. When the filling ratio of suspended carriers in the anoxic reactor was 50% and the inner-circulating ratio was 200% ,the removal efficiency of TN could reach 65.65% ,and the removal cfficiencies of CODCr and NH4^ ＋ -N in Anoxic-Oxic MBBR could be 90.70% and 71.65% respectively. In the test, the removal efficiencies of CODer and NH4^＋-N in the sewage showed obvious declines when the temperature in the MBBR was changed from normal to low,but they could be improved by regulating factors such as the filling ratio of carriers, DO mass concentration,hydraulic retention time, etc. in the reactor to ensure better removal efficiencies of CODCr and NH^＋4 -N.