不同运行负荷下C/N比对CANON工艺脱氮效能影响

Effect of C/N Ratio on the Nitrogen Removal Performance of CANON Process under Different Operating Loads

采用两组平行的ABR-CSTR组合反应器处理含DMF废水,前置ABR为厌氧氨化系统,后置CSTR-CANON区实现系统脱氮。采取间歇曝气策略控制DO在0.5 mg/L以下,探究通过弱化氨化反应逐步提高C/N比对不同运行负荷下CANON系统脱氮效能及微生物群落影响。结果表明,进水C/N比为0.5~0.8,低负荷(R1)、高负荷(R^(2))反应器均成功实现对DMF废水的处理,TN去除率分别达到94%和80%;R^(2)反应器系统C/N比达到阈值1.7后,脱氮机制向传统硝化反硝化转变,而R1反应器则逐渐恢复稳定。微生物高通量测序表明,R1、R^(2)反应器功能菌受有机物冲击影响差异显著,Denitratisoma在两反应器脱氮功能菌中皆占据优势地位,其丰度分别为7.5%、14.71%,Nitrosomonas和Candidatus Brocadia在R1(3.16%至0.92%、维持1.74%不变)和R^(2)(0.23%到0.294%、4.29%至1.05%)反应器中丰度变化差异明显。

In this study,two sets of parallel ABR-CSTR combined reactors were used to treat wastewater containing DMF.The front ABR was an anaerobic amination system,and the rear CSTR-CANON zone was used to achieve nitrogen removal from the system.The intermittent aeration strategy was adopted to control the DO below 0.5 mg/L,and the effect of gradually increasing the C/N ratio by weakening the ammoniating reaction on the nitrogen removal performance and microbial community of the CANON system under different loads was explored.The results showed that the influent C/N ratio was 0.5-0.8,and both low-load(R1)and high-load(R^(2))reactors successfully achieved the treatment of DMF wastewater,with total nitrogen removal efficiency reaching 94%and 80%respectively.After the C/N ratio of R^(2) reactor system reached the threshold value of 1.7,the nitrogen removal mechanism changed to traditional nitrification and denitrification,and the R1 reactor could gradually return to stability.Microbial high-throughput sequencing showed that the functional bacteria in the R1 and R^(2) reactors were significantly affected by the impact of organic matter.Denitratisoma occupied a dominant position in the nitrogen removal functional bacteria in the two reactors,with abundances of 7.5%and 14.71%.The abundances of Nitrosomonas and Candidatus Brocadia changed significantly in the reactors of R1(from 3.16%to 0.92%,maintaining at 1.74%)and R^(2)(from 0.23%to 0.294%,from 4.29%to 1.05%).