侧流FNA抑制的CANON颗粒-絮体复合系统参数优化

为探究侧流游离亚硝酸(FNA)处理抑制亚硝酸盐氧化菌(NOB)策略相关工艺参数的最佳组合,在颗粒-絮体复合系统的全程自养脱氮(CANON)工艺中,采用批次试验探讨污泥沉降时间、FNA处理浓度及处理时间对相关功能菌活性的影响,针对性抑制NOB活性,降低FNA对功能菌活性影响。结果显示,沉降时间影响处理污泥中功能菌群活性,随着沉降时间的延长,排出污泥中厌氧氨氧化菌(AnAOB)活性逐渐减弱。沉降1min后进行排泥排出了大部分NOB并且反应器内保留了尽可能多的AnAOB,此时排出的污泥中AnAOB、氨氧化菌(AOB)和NOB的相对活性分别为15.79%、54.55%和68.63%。综合FNA对NOB和AOB活性的影响,采用0.6mg/L的FNA抑制12h后AOB活性为38.71%,而NOB活性仅为12.5%。响应曲面分析结果显示,FNA处理时间、处理浓度是影响NOB、AOB活性的关键因素。

Parameter optimization of CANON granular-flocculate composite system with side-flow FNA suppression

In order to explore the best combination of process parameters related to the strategy of inhibiting nitrite oxidizing bacteria (NOB) by side flow free nitrous acid (FNA) treatment, in the completely autotrophic nitrogen removal over nitrite (CANON) process of granular-flocculate composite system, batch test was used to explore the effects of sludge sedimentation time, FNA treatment concentration and FNA processing and processing time to the related functional bacteria activity influence. The NOB activity was targeted inhibition and treatment time on the activity of relevant functional bacteria, so as to inhibit the activity of NOB and reduce the effect of FNA on the activity of functional bacteria. The result showed that the settling time affected the activity of functional bacteria in the treated sludge. With the prolongation of the settling time, the activity of anaerobic ammonium oxidizing bacteria (AnAOB) in the discharged sludge gradually decreased. After settling for 1min, most of the discharged sludge was NOB, and retained as much AnAOB as possible in the reactor. At this time, the relative activities of AnAOB, ammonia oxidizing bacteria (AOB) and NOB were 15.79%, 54.55% and 68.63%, respectively. Considering the effect of FNA on the activity of NOB and AOB, the activity of AOB was 38.71%, while the NOB activity was only 12.5% after inhibition with 0.6mg/L FNA for 12h. The results of response surface analysis showed that the treatment time and treatment concentration of FNA were the key factors affecting the activity of NOB and AOB.