CAST池活性污泥除磷微生物群落特征研究

Study on dephosphorisation microorganism community of activated sludge in CAST reaction tank

为掌握霞山水质净化厂CAST池各反应段活性污泥除磷微生物群落结构特征,特对CAST池内不同区活性污泥进行采样并DNA提取后高通量测序分析,结果表明CAST池各阶段活性污泥富集了丰富的具有良好除磷功能的菌。门水平上的优势除磷菌有变形杆菌门(Proteobacteria)、绿弯菌门(Chloroflexi)、放线菌门(Actinobacteriota)、酸杆菌门(Acidobacteriota)、厚壁菌门(Firmicutes)。属水平上的优势除磷菌为Norank_f_Caldilineaceae、Candidatus_Competibacter、Norank_f_norank_o_Saccharimonadales、Tetrasphaera、Norank_f_Blastocatellaceae等。该CAST池活性污泥中存在聚磷菌与聚糖菌共存的现象且两者相对丰度较高,两者的竞争及环境条件变化会导致除磷效果的波动。主反应区曝气使得好氧聚磷菌Tetrasphaera相对丰度远高于生物选择区和兼氧区。反硝化聚磷菌Streptococcus和Acinetobacter在生物选择区中相对丰度远高于兼氧区和主反应区。反硝化聚磷菌在生物选择区厌氧段更加适宜其生长导致其相对丰度较高,能增强该阶段除磷效果。在实际生产中应着力改善合适环境条件提升聚磷菌生物量以保障除磷效果。

In order to grasp the characteristics of the dephosphorization microbial community structure of the activated sludge in each stage of the CAST reaction tank in Xiashan Water Treatment Plant in Zhanjiang,China,the high-throughout sequencing analysis was performed on the activated sludge at different stages of the CAST reaction tank after DNA extraction.The results indicate that the activated sludge at each stage of the CAST reaction tank was rich in dephosphorization bacterial,and it performs efficiently in phosphor removing.The dominant bacterial groups at the phylum level included Proteobacteria、Chlorofleri、Actinobacteriota、Acidobacteriota and Firmicutes.The dominant flora at the genus level mainly included Norank_f_Caldilineaceae、Candidatus_Competibacter、Norank_f_norank_o_Saccharimonadales、Tetrasphaera、Norank_f_Blastocatellaceae and so on.The phosphorus accumulating organisms and glycogen accumulating organisms were coexisted in the CAST reaction tank,the relative abundance of these two bacteria were relatively high,the competition between the bacteria and the change of the environmental condition will affect the efficiency of the phosphor removal.Due to long-time aeration in main reaction zone,the relative abundance of Tetrasphaera in main reaction zone much higher than the biological selection zone and facultative oxygen zone.The relative abundance of Streptococcus and Acinetobacter in the biological selection zone was much higher than that in the main reaction zone and the facultative oxygen zone.The denitrification phosphorus accumulating bacteria were more suitable for its growth in the anaerobic stage of the biological selection zone,resulting in a higher relative abundance,which leads to enhance the phosphorus removal efficiency of this stage.In actual production,efforts should be made to improve suitable environment to enhance the biomass of phosphorus accumulating bacteria to ensure the phosphorus removal effect.