DO对PU填料系统脱氮功能菌数量的影响  

Effect of Dissolved Oxygen on Amount of Functional Bacteria for Nitrogen Removal in Polyurethane Filler System

作　　者：赵丽敏[1] 张朝升[1] 曹勇锋[1] 荣宏伟[1] 张可方[1] 

机构地区：[1]广州大学珠江三角洲水质安全与保护省部共建教育部重点实验室,广东广州510006

出　　处：《中国给水排水》2017年第3期1-6,共6页China Water & Wastewater

基　　金：国家自然科学基金资助项目(51278133;21477027);广东省科技计划项目(2014A020216049;2014A020216048);广州市教育系统创新团队项目(13C01)

摘　　要：利用聚氨酯(PU)填料构建序批式生物膜反应器(SBBR)以实现同步硝化反硝化。在不同DO浓度条件下稳定运行的系统中分别提取生物膜样品的基因组DNA,选取总细菌、亚硝化菌(AOB)、硝化菌(NOB)和反硝化菌四种目的基因,采用实时荧光定量PCR技术对脱氮功能菌进行定量分析,研究DO对系统运行效能及功能菌数量的影响。从荧光定量PCR结果分析,在进水NH_4^+-N为20~25 mg/L及5种不同DO浓度下,DO为2.5、3.5、4.5 mg/L时,AOB数量相差不大,拷贝数为7.75×10~5~8.60×10~5copies/ng;低DO(1.5 mg/L)或高DO(5.5 mg/L)都会引起AOB的大幅减少;在DO=2.5 mg/L时NOB和反硝化菌的数量达到最大值,对NH_4^+-N的去除率较高,为93.30%,对TN的去除率最高,为83.73%。综合来看,DO的最佳浓度为2.5 mg/L,此时系统运行效能最佳,各功能菌达到和谐稳定的微环境状态。Polyurethane （PU） fillers were used in sequencing batch biofilm reactor （SBBR） to achieve simultaneous nitrification and denitrification （SND）. Genomic DNA of total bacteria, ammonia- oxidizing bacteria （AOB）, nitrite-oxidizing bacteria （NOB） and denitrifying bacteria were extracted from biofilm in the stable systems at different DO concentrations. To investigate the effect of DO concentration on the system＇ s performance and the amount of functional bacteria, the real-time PCR technology was used to quantitatively analyze the functional bacteria for nitrogen removal. The results showed that at the NH4＋^ - N concentration of 20 to 25 mg/L, the amounts of AOB at DO concentrations of 2.5 mg/L, 3.5 mg/L and d. 5 mg/L were similar with average copy numbers of 7.75 × 10^5 to 8.60× 10^5 copies/ng. Both of low DO concentration （1.5 mg/L） and high DO concentration （5.5 mg/L） could significantly reduce the amount of AOB. The amounts of NOB and denitrifying bacteria were the highest at DO concentration of 2.5 mg/L, and the maximum removal rates of NH4＋^ -N and TN were 93.30% and 83.73% , respectively. On the whole, when DO concentration was 2.5 mg/L, the system had a good performance, and all bacteria were under a harmonious microenvironment.

关 键 词：DO浓度 同步硝化反硝化 序批式生物膜反应器 聚氨酯填料 荧光定量PCR 氨氧化菌 硝化菌 反硝化菌 

分 类 号：X172[环境科学与工程—环境科学] X703