MBR系统CANON工艺的快速启动及微生物种群特征

The fast start-up of CANON process in MBR system and the characterization of microbes

为了考察CANON工艺的快速启动策略及功能微生物的种群特征,在常温MBR反应器内接种普通活性污泥后间歇运行.启动策略为以调控曝气时间和曝气量作为主要方法,首先在限氧条件下启动亚硝化,之后进一步降低DO启动CANON工艺.在CANON工艺启动成功后,通过调整曝气时间和无机碳源浓度提高了总氮去除负荷,并采用PCR-DGGE技术分析了稳定运行的CANON工艺内功能微生物的种群特征.结果表明,CANON工艺经36d成功启动,NH4+-N去除率和总氮去除率最终稳定在99%和84%左右,氮去除负荷达到0.41kg/(m3·d).DGGE测序结果表明,Nitrosomonas和Candidatus Kuenenia stuttgartiensis是反应器内的优势菌种,两种微生物协同作用,共同在MBR内完成了高效的自养脱氮.

To investigate the fast start-up of CANON process and characterization of functional microbes, conventional activated sludge was inoculated to an MBR and the reactor was operated intermediately at ambient temperature. In the launch strategy, the regulation of aeration and aeration time was used as the main method. First, partial nitrification was applied under oxygen-limited condition. Secondly, DO had to be decreased further to achieve CANON process. Finally, aeration time and inorganic carbon concentration needed to be adjusted to improve the total nitrogen removal rate. Besides, the characterization of functional microbes in stable CANON process was analyzed using PCR-DGGE techniques. The results showed that the CANON process launched successfully after 36 days, the ammonium removal rate and total nitrogen removal rate were kept at around 99% and 84% and the maxinum nitrogen removal rate can reach 0.41kg/（m^3·d）. DGGE profiles showed Nitrosomonas and Candidatus Kuenenia stuttgartiensis were predominant microbes in the reactor and they worked synergetically to form an efficient autotrophic nitrogen removal process within the MBR.