污水处理中微生物反硝化脱氮过程及代谢规律  

Denitrifying Denitrification Process and Metabolic Rule of Microorganisms in Wastewater Treatment

作　　者：吉芳英[1] 陈思[1] 刘娜[1] 

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《四川理工学院学报（自然科学版）》2013年第4期10-14,共5页Journal of Sichuan University of Science & Engineering(Natural Science Edition)

摘　　要：微生物同化、异化反硝化均依赖碳源,且同化C/N为23远高于异化C/N。污水系统中反硝化菌多为兼性厌氧菌,其反硝化效果受DO、碳源种类、温度等因素影响较大。DO与NO3--N为竞争关系,DO存在会抑制反硝化,但高DO有利于反硝化菌的生长。不同碳源反硝化所需C/N不同,污水为碳源时所需的C/N约为4.0-5.0,污泥内源呼吸时反硝化C/N最低为2.9-3.2,但其反硝化速率仅为利用VFA时的1/10。常见VFA如甲醇、乙酸等C/N为3.1-4.1。反硝化过程中还应注意温室气体N2O逸出等问题,偏酸性及较高DO会导致反硝化过程N2O积累与逸出。Both assimilatory nitrate reduction and dissimilatory denitrification all need organic substances, and the C/N ratio of assimilatory nitrate reduction is about 23, which is much higher than dissimilatory denitrification. Most of denitrifying bacteria in the sewage system are facultative anaerobe whose denitrification effect is greatly influenced by many factors such as DO, carbon source type and temperature, etc. DO competes with NO3--N, the exist of DO will inhibit denitrification. However＇ the high DO is conducive to the growth of denitrifying bacteria. For different carbon source the C/N need in denitri- fication is different, the C/N is about 4. 0 -5.0 when the carbon source is waste water, the denitrification C/N of endoge- nous respiration is at least about 2.9 - 3.2, but it＇s denitrification rate is one-tenth of that when the carbon source is VFA. The C/N of some common VFA such as methanol, acetic acid and so on, is about 3.1 - 4. 1. The phenomenon of greenhouse gas N2O escape during denitrification should be noted. N2O would accumulate and escape in denitrification process in condi- tion of weak acidity or high DO.

关 键 词：反硝化 微生物代谢 低碳源污水 

分 类 号：X703.1[环境科学与工程—环境工程]