拔风管对CANON型人工湿地脱氮性能的影响  

Effect of air duct on nitrogen removal performance of a constructed wetland system with CANON process

作　　者：赵子健 程瑞 何凯雯 胡晶晶 胡莹莹 王振[1] ZHAO Zi-jian;CHENG Rui;HE Kai-wen;HU Jing-jing;HU Ying-ying;WANG Zhen(School of Resources and Environment,Anhui Agricultural University,Hefei 230036,China)

机构地区：[1]安徽农业大学资源与环境学院,安徽合肥230036

出　　处：《中国环境科学》2022年第3期1191-1201,共11页China Environmental Science

基　　金：国家自然科学基金资助项目(51508002);安徽省重点研究与开发计划资助项目(202004h07020024,201834040011);安徽省自然科学基金资助项目(2008085ME162);中国科学院城市污染物转化重点实验室开放基金资助项目(KLUPC-KF-2020-5)。

摘　　要：以猪场沼液为处理对象,探究了拔风管对基于亚硝化的全程自养脱氮(CANON)型潮汐流人工湿地(TFCW)氮素转化性能及微生物种群结构的影响.结果表明,拔风管数量可显著影响CANON型TFCW中脱氮功能微生物的数量与活性,进而影响其氮素转化速率.在水力负荷(HLR)≤0.18m^(3)/(m^(2)·d)的前提下,随着拔风管数量由0增至6,TFCW填料层中的氧环境逐渐优化,促进了其中短程硝化性能的提高与厌氧氨氧化菌的富集,进而使系统中形成了同步亚硝化、厌氧氨氧化与反硝化耦合反应体系,其脱氮效能不断提高;而当拔风管数量>6后,填料层中亚硝酸盐氧化菌的过量增殖破坏了短程硝化作用的稳定性,厌氧氨氧化作用与反硝化作用随之受阻,系统脱氮性能复又有所下降.当HLR=0.18m^(3)/(m^(2)·d)且拔风管数量为6时,TFCW中Nitrosomomas和Candidutus Brocadia2种菌属的相对丰度分别可达20.05%和18.38%,而Nitrospira的相对丰度仅为1.92%,此时CANON作用可得到较大限度的强化,且可与Denitratisoma等菌属主导的反硝化作用耦合,使系统的TN和NH;-N去除率分别达(90.29±3.70)%和(93.30±2.97)%.This study was conducted to explore the effects of air duct on nitrogen transformation mechanisms and the associated microbiological characteristics in a tidal flow constructed wetland(TFCW) with CANON process when treating digested swine wastewater. The results showed that, the air duct number significantly affected quantities and activities of the functional microbes in the TFCWs. Correspondingly, nitrogen transformation rates in the systems fluctuated at the different five numbers of air duct. On the premise that the hydraulic loading rate(HLR) was no more than 0.18 m^(3)/(m^(2)·d), the redox microenvironment gradually optimized in the bed of the TFCW as the air duct number increased from 0 to 6, which was conductive to the enhancement of nitritation and the enrichment of ANAMMOX bacteria(AnAOB). Subsequently, the simultaneous nitrification, ANAMMOX, and denitrification(SNAD) processes occurred in the TFCW, resulting in the improvement of nitrogen removal in the system. However, as the air duct number was more than 6, the stabilization of nitritation in the TFCW was impaired partly owing to the proliferation and increased activities of nitrite oxidizing bacteria(NOB), and then the ANAMMOX process and the denitrification process were both inhibited with the nitrogen removal performance of the system declined. Regarding to the TFCW operating with HLR of 0.18 m^(3)/(m^(2)·d), as the air duct number was 6, the relative abundances of Nitrosomomas(the major bacteria of AOB) and Candidutus Brocadia(the major bacteria of AnAOB) could respectively reach up to 20.05% and 18.38% in the system, while the relative abundances of Nitrospira(the major bacteria of NOB) was at a low level of 1.92%. Correspondingly, the CANON process was enhanced effectively in the system, and this process could be coupled with the denitrification process dominated by Denitratisoma(the major bacteria of denitrifiers) with the relative abundance of 15.18%, resulting that the TN and NH4+-N removal rates of the TFCW were(90.29±3.70)% and(93.30±

关 键 词：潮汐流人工湿地(TFCW) 拔风管 基于亚硝化的全程自养脱氮(CANON) 短程硝化 氮素转化 

分 类 号：X703.1[环境科学与工程—环境工程]