一体式A^2/O-MBR内的DO分布模拟及影响因素研究  

Simulation and study of factors affecting on distribution of dissolved oxygen in A^2/O-MBR process

作　　者：袁星[1] 杨敏[1] 罗南[1] 樊耀波[1] 

机构地区：[1]中国科学院生态环境研究中心,北京100085

出　　处：《膜科学与技术》2016年第1期61-71,共11页Membrane Science and Technology

基　　金：国家自然科学基金(51278483)

摘　　要：基于计算流体力学(CFD)的方法,将氧传质模型与之进行耦合,对一体式A2/O-MBR内部流场特性及溶解氧(DO)浓度分布进行模拟,并且分析了曝气量、污泥浓度及气泡直径对DO分布的影响.研究结果表明,随着曝气量的增大,DO浓度升高,好氧区域范围扩大;随着污泥浓度的增大,DO浓度随之降低,而对液体流速的影响不明显;随着气泡直径的增大,DO浓度明显降低,膜面剪切力则明显升高,而反应器内部速度场变化不显著.研究发现存在一个较低的曝气量和适中的气泡直径,使一体式A2/O-MBR可在较低能耗的条件下,较好的满足脱氮除磷条件及内部流场强度的需求.The fluid characteristics and the distribution of dissolved oxygen in an A2/O-MBR were simula- ted by coupling computational fluid dynamics （CFD） with the oxygen mass transfer model in this paper. And the factors influencing on the distribution of dissolved oxygen considered for this work were aeration rate, sludge concentration and bubble diameter. The results indicated that the higher aeration rate could result in higher dissolved oxygen concentration and bigger aerobic zone, however, on the contrary, the higher sludge concentration would cause lower dissolved oxygen concentration; with increasing the bubble diameter, the dissolved oxygen concentration decreased significantly and the wall shear stresses on mem- brane were increased sharply but the liquid velocity in the A2/O-MBR was not affected obviously. It also showed that there may be a lower value of aeration rate and a moderate data of bubble diametei＂ to establish the desire conditions for denitrification and phosphorus removal with lower energy consumption in the A2/ O- MBR.

关 键 词：计算流体力学 氧传质 一体式A2/O-MBR DO分布 

分 类 号：X703.1[环境科学与工程—环境工程]