膜曝气生物反应器内DO分布变化及其对有机物和氮去除的影响  

Distribution change of DO and its influence on organic and nitrogen removal in membrane aeration bioreactor

作　　者：刘琪 程方 张文丽[1,2] 张景丽 杨南阳 樊星[1] 

机构地区：[1]天津城建大学环境与市政工程学院,天津300384 [2]天津市水质科学与技术重点实验室,天津300384

出　　处：《环境工程学报》2017年第12期6246-6251,共6页Chinese Journal of Environmental Engineering

基　　金：国家科技支撑计划项目(2012BAB17B02);天津市科技计划项目(13ZXCXSF06100)

摘　　要：以模拟生活污水为研究对象,探讨膜曝气生物反应器在不同的曝气压力下溶解氧的分布特征,并分析了DO的分布对有机物和氮去除率的影响。研究结果表明,不同的曝气压力下,沿曝气膜径向位置DO值逐渐降低呈梯度分布,轴向位置的DO浓度变化随沿程氧分压减小逐渐降低;不同位置的DO分布差异影响反应器内微生物群落的分布情况,进而影响碳氮的去除效果。COD和NH_4^+-N去除主要依靠生物膜内的好氧异养菌,去除率随DO的上升而增大,当反应体系中DO浓度在1.71 mg·L^(-1)以上时,两者的最大去除率分别为84.4%和92.1%;TN的去除率随DO的上升而减小,在低DO的主体料液中,生物膜内侧依然保持高氧低碳环境,在保证硝化反应的同时反硝化作用进行较为充分,去除率可高达76.1%。Using simulated domestic wastewater, the distribution characteristics of DO were studied under different aeration pressures in a membrane aeration bioreactor and the effects of DO variation on the removal rates of organics and nitrogen were analyzed.The results showed that radially along the aeration membrane, the DO concentration was distributed on a gradient and decreased gradually under different aeration pressures.The DO concentration decreased axially as well, along with a decrease in oxygen partial pressure.The changes in the microbial communities in the reactor by the DO distributional differences led to the efficient removal of carbon and nitrogen.COD and NH4＋-N removal relied mainly on the aerobic heterotrophic bacteria inside the biofilms, as these removal rates increased as DO increased.When the DO concentration in the reaction system was more than 1.71 mg·L-1, the maximum removal rates of COD and NH4＋-N were 84.4% and 92.1%, respectively.The TN removal rate decreased with an increase in DO, but was as high as 76.1% in the liquids with low DO concentration because the inside of the biofilms maintained high oxygen levels and low carbon environments, guaranteeing full nitrification and denitrification.

关 键 词：膜曝气生物反应器 DO 除碳脱氮 

分 类 号：X52[环境科学与工程—环境工程]