摘要
采用PIV荧光粒子法研究了1.0、1.5、2.5mm 3种不同的曝气孔径下，不同曝气强度对膜面气液两相流流场流体力学的影响。实验应用Size—Shape—Analysis模块分析了在曝气孔径为1.5mm、曝气强度为24L/h条件下，膜面流场中气泡的运动规律以及3种不同曝气孔径在曝气强度为24、48、72、96、140、180、220L/h下近膜面雷诺应力的变化规律。结果表明由1.5mm曝气孔径产生气泡运动过程中，气泡形态呈椭圆形，等效直径主要集中在5~6mm之间，大部分气泡速度集中在0.1～0.2m/s之间;曝气强度的增加与雷诺应力的变化呈正相关关系;在本实验条件下，1.5mm曝气孔径、140L/h曝气强度下可产生较大的雷诺应力的变化，为最佳曝气孔径与曝气强度取值。本研究为优化膜生物反应器内流场进而减轻膜污染提供了理论依据。
Submerged membrane bio-reactor （SMBR）is a high-efficiency wastewater treatment technology that combines membrane separation technology with traditional biological treatment technology. The effect that regularity of aeration intensity and aeration pore sizes on fluid mechanics characteristics of hollow fiber membrane surface was analyzed based on the PIV fluorescent particle technology. The bubbles movement of flow field near membrane surface in the aeration pore was studied when its size was 1.5mm by using Size—Shape—Analysis modular, and the changing rule of Reynolds stress on the surface of membrane under seven aeration intensities of 24L/h, 48L/h, 72L/h, 96L/h, 140L/h, 180L/h and 220L/h was investigated. The results indicated that the bubble shape was oval and its equivalent diameter was concentrated in 5～6mm when bubble aeration was exercised by the 1.5mm aperture with velocities on the bubble were 0.1～0.2m/s. Aeration intensity was positively correlated with Reynolds stress. Aeration pore size of 1.5mm and aeration intensity of 140L/h was considered as the best aeration pore size and aeration intensity values, because it can provide a greater Reynolds stress. This subject laid a theoretical foundation for the optimization of flow field in membrane bioreactor so as to improve the membrane fouling problem.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2016年第12期373-378,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51263013)
内蒙古工业大学科学研究重点项目(ZD201508)
关键词
浸没式膜生物反应器
PIV荧光粒子法
气液两相流
雷诺应力
submerged membrane bioreactor
PIV fluorescent particle method
gas-liquid two phaseflow
Reynolds stress
