吸附-全程自养脱氮(A-CANON)工艺处理实际市政污水

The performance of the adsorption(A)-CANON process treatment municipal wastewater

以上海某污水处理厂市政污水为研究对象,考察市政污水在常温(25℃)条件下先经吸附段(A段)去除回收部分碳源后利用全程自养脱氮(CANON)工艺处理的脱氮效果.A-CANON工艺稳定运行175个周期, A段水力停留时间(HRT)=20min,DO=2mg/L, COD去除率始终高于60%,出水C/N降至1.5左右;CANON段出水中COD及TN浓度分别低于50mg/L和15mg/L,NH_4^+-N浓度一般低于5mg/L,基本满足城市污水厂一级A排放标准.16S r DNA高通量测序结果显示,采用A-CANON工艺后,CANON系统中的优势厌氧氨氧化菌属为Candidatus_Jettenia和Candidatus_Brocadia.其中,Candidatus_Jettenia的丰度由第85周期的1.79%增加到第175周期的13.51%,较同期丰度降低1.4%的Candidatus_Brocadia表现出更强的环境适应能力.研究结果表明采用A-CANON工艺可有效处理市政污水并回收其中碳源.为该工艺在市政污水处理中的应用提供了理论依据和技术支持,有望实现市政污水碳、氮处理的可持续性.

Adsorption(A)-CANON process was proposed to verify the feasibility of using this process to treat municipal wastewater from wastewater treatment plants.The adsorption unit was established for the carbon adsorption and recycling,then the low C/N wastewater(effluent of the A unit)entered the CANON unit for the autotrophic nitrogen removal.This process ran stably for 175 cycles and exhibited robust carbon and nitrogen removals.At HRT=20min and DO=2mg/L,the removal efficiency of COD in the A unit reached more than 60%with effluent C/N declining to about 1.5.In the CANON unit,the effluent COD,TN and NH4^+-N were lower than 50mg/L,15mg/L and 5mg/L,respectively,which basically have met the wastewater discharge standard for A standard,first class.The 16S rDNA high throughput sequencing showed that the dominant anammox bacteria was Candidatus_Jettenia and Candidatus_Brocadia.Candidatus_Jettenia can adaptable for the low ammonia and normal temperature environment better than Candidatus_Brocadia while using the A-CANON process,i.e.the abundance of Candidatus_Jettenia increased from 1.79% in the 85^th cycle to 13.51% in the 175^th cycle while that of Candidatus_Brocadia reduced by 1.4%.The results proved that the A-CANON process can treat municipal sewage effectively as well as recycle the carbon,which provides theoretical basis and technical support for its sustainable application on municipal wastewater treatment.