全程自养颗粒污泥快速启动及混合营养型脱氮性能分析

在连续流条件下，基于颗粒污泥全程自养脱氮（CANON）工艺的快速启动和混合营养条件下高效脱氮，是CANON工程应用的重要环节.本研究在气提内循环反应器（AIR）中，以老化的CANON颗粒污泥经机械破碎至0.3 mm作为种泥，实现混合营养型单级颗粒污泥同步脱氮除碳.启动26 d，通过控制DO，系统出现稳定的部分硝化，再缩短HRT提升氨氮负荷至5.65 kg ·（m³ ·d）^-1，促进颗粒化和厌氧氨氧化；第68 d，总氮去除率达到58%之后，进水加入有机物，C/N从0提升到0.25和0.5，促进AOB、AMX和异养微生物的协同，氨氮去除率达95%，总氮去除率达85%，COD去除率达80%左右.COD浓度增加，能较好地抑制Nitrospira菌属等NOB的活性，q（NH₄⁺-N）和q（TN）稳定在0.4 g ·（g ·h）^-1和0.34 g ·（g ·h）^-1，q（NO₃^--N）约为0.02 g ·（g ·h）^-1.采用MiSeq高通量测序对微生物多样性分析，表明有机物对污泥中Nitrosomomas和Candidutus_Kuenenia丰度未产生显著影响，增加了Candidutus_Brocadia菌属以及具有反硝化功能Denitratisoma等菌属的丰度.这对于快速启动连续流CANON颗粒污泥工艺处理低C/N比废水提供思路.

Analysis of Rapid Start-up and Mixed Nutritional Nitrogen Removal Performance of Complete Autotrophic Granular Sludge

A rapid start of the completely autotrophic nitrogen removal over nitrite (CANON) process based on granular sludge and efficient nitrogen removal under mixotrophic conditions are important steps in a continuous flow reactor for CANON engineering applications. In this study, an aged CANON granular sludge was mechanically crushed to 0.3 mm as inoculum in an airlift internal-loop reactor (AIR) to achieve simultaneous COD removal and mixotrophic denitrification of the single-stage granular sludge. The system achieved stable partial nitrification by controlling DO after 26 days of startup. Granulation and anaerobic ammonia oxidation were then promoted by shortening the HRT to increase the ammonia nitrogen load to 5.65 kg ·(m³ ·d)^-1. The total nitrogen removal rate reached 58% on the 68^th day. Subsequently, the C/N ratio of influent was increased from 0 to 0.25 and 0.5, which promoted the synergistic growth of AOB, AMX, and heterotrophic microorganisms. The removal rates of ammonia and total nitrogen were 95% and 85% respectively, and the removal of COD reached approximately 80%. The activity of NOB such as Nitrospira was effectively inhibited as the COD concentration was increased. q(NH₄⁺-N) and q(TN) were stable at 0.4 g ·(g ·h)^-1 and 0.34 g ·(g ·h)^-1, respectively, while q(NO₃^--N) was approximately 0.02 g ·(g ·h)^-1. Microbial diversity was observed using MiSeq high-throughput sequencing. It showed that organic carbon had no significant effect on the abundance of Nitrosomomas and Candidutus_Kuenenia, while increasing the abundance of Candidutus_Brocadia and Denitratisoma in the sludge. This study provides ideas for the rapid start of continuous flow CANON granular sludge process to treat wastewater with low C/N ratio.