运行模式对同步短程硝化反硝化脱氮及微生物群落特征的影响

采用复合序批式生物膜反应器（HSBBR）处理高盐废水，实现了同步短程硝化反硝化脱氮。考察了运行模式对同步短程硝化反硝化系统COD去除和脱氮性能的影响，利用高通量测序技术分析了微生物群落的变化。结果表明:当反应器以缺氧/好氧交替模式运行时（缺氧/好氧时间比为2.0 h/4.5 h），NH₃-N、总无机氮（TIN）和COD去除率分别为95.00%、84.83%和86.72%，出水中含有NO₂--N和NO₃--N。以完全好氧模式运行时（缺氧/好氧时间比为0.0/6.5 h），NH₃-N去除率达到100.00%，TIN和COD去除率分别为85.94%和89.46%，出水中只含有NO₂--N。高通量测序结果表明:在门水平上，2种模式下生物膜和悬浮污泥中的优势菌均为变形菌门（Proteobacteria）和拟杆菌门（Bacteroidetes）；Nitrosomonas是本研究检测出的唯一氨氧化菌（AOB）属，当反应器由缺氧/好氧交替模式转换为完全好氧模式时，悬浮污泥和生物膜中Nitrosomonas的相对丰度均增加；悬浮污泥和生物膜中优势反硝化菌属相似，包括Candidatus_Competibacter、Paracoccus、Thauera和Denitratisoma，在完全好氧模式下，悬浮污泥和生物膜中Candidatus_Competibacter和Thauera的相对丰度较低，而Paracoccus和Denitratisoma的相对丰度较高。多种反硝化菌与氨氧化菌的共同作用，使反应器能够实现高效同步短程硝化反硝化脱氮。

EFFECT OF OPERATIONAL MODE ON NITROGEN REMOVAL AND MICROBIAL CUMMUNITY IN PROCESS OF SIMULTANEOUS PARTIAL NITRIFICATION AND DENITRIFICATION

In this study, simultaneous partial nitrification and denitrification (SPND) process was successfully established for the treatment of high-salinity wastewater in a hybrid sequencing batch biofilm reactor (HSBBR). The effect of operational mode on the reactor performance and microbial community was investigated. When the reactor was operated in alternating anoxic/aerobic mode (anoxic/aerobic hour ratio was 2.0 h/4.5 h), the removal efficiencies of NH₄+-N, total inorganic nitrogen (TIN) and COD were 95.00%, 84.83% and 86.72%, respectively, and the effluent contained nitrite and nitrate. When operational mode was switched to fully aerobic mode (anoxic/aerobic hour ratio was 0.0/6.5 h), removal efficiencies of NH₃-N, TIN and COD increased to 100.00%, 85.94% and 89.46%, and nitrate was the only nitrogen component in the effluent. The high-throughput sequencing results showed that the dominant phyla were Proteobacteria and Bacteroidetes in both suspended sludge (S-sludge) and biofilm in two modes. Genus Nitrosomonas was the only ammonia-oxidizing bacteria (AOB) detected in this study and appeared higher relative abundance in S-sludge and biofilm samples in the fully aerobic mode compared to the alternating anoxic/aerobic mode. S-sludge and biofilm shared similar dominant denitrifying bacteria (DNB), including genera Candidatus_Competibacter, Paracoccus, Thauera and Denittrasoma. The relative abundance of Candidatus_Competibacter and Thauera decreased in fully aerobic mode, while Paracoccus and Denitratisoma showed increasing tendency. Multiple DNB genera accompanied by AOB contributed to the efficient nitrogen removal via SPND process.