碳源类型对以NO_2^-为电子受体短程反硝化过程的长期和短期影响  

Long-and short-term effects of carbon source on denitritation process using nitrite as electron acceptor

作　　者：孙洪伟[1] 赵华南[1] 吕心涛 尤永军 

机构地区：[1]兰州交通大学环境与市政工程学院,兰州730070

出　　处：《环境工程学报》2016年第9期4657-4662,共6页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51168028;51168027;51668031);甘肃省自然科学基金项目(1606RJZA009)

摘　　要：短程生物脱氮是未来污水生物处理的主流技术,其反硝化过程是实现氮去除的关键步骤。碳源类型是NO-2还原过程的重要因素之一,为选择适于以NO-2为电子受体的反硝化碳源,采用序批式反应器(SBR),考察4种碳源(乙酸钠、甲醇、乙醇和生活污水)对NO-2为还原过程长期和短期影响。实验结果表明,微生物对不同碳源具有较强的适应性,经过一定时间的驯化,可明显提高微生物的反硝化能力,与未驯化时相比,还原速率分别提高3.1、2.1、1.7和2.4倍。培养初期,四种碳源条件下NO-2还原速率的大小关系为:r乙醇=1.3r乙酸钠=2.6r生活污水=3.8r甲醇。长期驯化稳定后,NO-2还原速率的大小关系为:r乙酸钠=1.4r乙醇=2.6r生活污水=4.3r甲醇。此外,经过驯化后,微生物可适应较高的p H值,增强抵抗p H波动的能力。当存在多种碳源时,微生物优先利用已驯化碳源。4种碳源中,乙酸钠最容易被微生物利用,还原速率为40.7 mg·(g·h)-1,而甲醇较难被微生物利用,其还原速率为26.2 mg·(g·h)-1。Short-cut biological nitrogen removal is the mainstream technology for biological wastewater treat- ment in the future, and denitrification is a crucial step for removing nitrogen. This research investigated the long- and short-term effects of carbon sources （sodium acetate, methanol, ethanol, and sewage） on nitrite reduction in order to select an appropriate carbon source for using nitrite as electron acceptor. The experimental results showed that the microbial population had strong adaptability to carbon sources and could significantly improve the denitrification ability, after the microbial population was tamed over a period of time. Compared with the un- tamed microbial population, the reduction rate of the tamed microbial population by the respective carbon sources increased 3.1, 2.1, 1.7, and 2.4 fold. At initial and steady states, the reduction rate relationships of the four carbon sources werer r ethanol=1.3r sodium acetate=2.6rsewage=3.8r methanol and r sodiam acctate =1.4r ethanol=2.6r sewage=4.3r methanol,respectively. In addition, the tamed microorganisms could tolerate higher pH values and had en-hanced ability to resist pH fluctuation. Moreover, when the four carbon sources coexisted, the microorganisms could utilize prior adaptive carbon sources. The sodium acetate was utilized easily by the microorganisms, with the reduction rate being 40.7 mg · （ g · h） - 1, whereas methanol was the most difficult to utilize, the reductionrate being 26.2 mg · （g ·h） -1.

关 键 词：碳源 SBR 短程反硝化 亚硝态氮 

分 类 号：X703[环境科学与工程—环境工程]