摘要
为了研究不同C/N条件下驯化的微生物的反硝化特性,采用SBR反应器在4种C/N比(0、5、10、15)条件下对微生物进行驯化.在此基础上,通过批次试验分别考察以NO-2-N、NO-3-N及NO-3-N+NO-2-N作为电子受体时,驯化的微生物的反硝化特性.试验结果表明,对于4种C/N比条件下驯化后的微生物,NO-2-N和NO-3-N两种电子受体均可以被完全还原,但还原速率差异明显.当以NO-2-N为电子受体时,4种C/N条件下驯化的微生物的还原速率分别为:0.67、1.10、1.66、0.24 mgN·L-1·min-1.当以NO-3-N为电子受体时,随着C/N的增加,4种C/N条件下驯化的微生物的还原速率逐渐增大,分别为:0.31、0.61、0.82 mgN·L-1·min-1和1.01 mgN·L-1·min-1.然而以NO-3-N+NO-2-N为电子受体时,在C/N为0和5条件下驯化的微生物还原NO-2-N的速率高于还原NO-3-N的速率,而在C/N为10和15条件下却相反.此外,在初始NO-x-N浓度及pH值相同条件下,NO-2-N单独还原过程引起的pH增量高于NO-3-N单独还原过程,而较低C/N条件下驯化的微生物同步还原NO-3-N和NO-2-N时,系统内pH的增量较高.
In order to investigate the denitrification characteristic of microbial population tamed with different C/N ratios, microbial population was tamed in sequencing batch reactor （ SBRs） with C/N ratios of 0, 5,10 and 15, respectively, and then the denitrification capability of the tamed microbial population was investigated. The effects of different electron acceptors （ nitrite, nitrate, nitrite＋nitirate） on the reduction capability of tamed microbial population were studied using batch tests. Results showed that both nitrite and nitrate were reduced by the tamed microbial population, but a significant difference in denitrification rate was observed. When nitrite was used as an electron acceptor, the nitrite reduction rates were 0.67, 1.10, 1.66 and 0.24 mgN·L-1·min-1 , respectively, for the tamed microbial population with four C/N ratios. The nitrate reduction rates were 0.31, 0.61, 0.82 and 1.01 mgN·L-1·min-1 , respectively, using nitrate as an electron acceptor. When nitrite and nitrate co-existed in the system, nitrite reduction rate was higher than those of nitrate for the tamed microbial population with C/N ratios of 0 and 5, while nitrite reduction rate was lower for the tamed microbial population with C/N ratios of 10 and 15. It was also found that pH increased more in nitrite＆amp;nbsp;reduction than in nitrate reduction. Significant increase of pH was obtained in co-existing system of nitrite and nitrate for tamed microbial population with C/N ratios of 0 and 5.
出处
《环境化学》
CAS
CSCD
北大核心
2014年第5期770-775,共6页
Environmental Chemistry
基金
国家自然科学基金项目(51168028)
甘肃省省青年基金计划项目(1107RJYA279)
兰州交通大学大学生创新计划项目(201078)资助
关键词
C/N
反硝化
还原速率
C/N
C/N
denitrification
reduction rate
