平板膜生物反应器膜间距与曝气气泡形态对膜污染形成的影响  

Effect of clearance between membranes and bubble shape upon membrane fouling in a flat-sheet membrane bioreactor

作　　者：王栋[1] 冯超[1] 陈亚中[1] 朱昊[1] 王琪[1] 崔鹏[1] 

机构地区：[1]合肥工业大学化学工程学院,安徽省可控化学与材料化工重点实验室,合肥230009

出　　处：《膜科学与技术》2014年第6期100-105,共6页Membrane Science and Technology

基　　金：安徽省高等学校自然科学研究项目(KJ2012A240)

摘　　要：以平板膜生物反应器为研究对象,研究了不同膜间距(4.0mm,8.0mm,12.0mm)和不同曝气管开孔直径(1.0mm,2.0mm,3.0mm)对膜污染的影响.同时建立了模拟膜生物反应器,采用摄像和图形分析法观测了气泡在膜间的上升运动.结果表明在相同比曝气量下,膜间距为4.0mm时,膜污染程度最轻.摄像和图形分析结果表明膜间距为4.0mm时,气泡形状为球帽形,气泡扭曲变形程度最大,单个气泡冲刷面积最大,但气泡上升速度由于"壁效应"而明显减小.在不同曝气孔径下比较了膜阻力上升速率和活性污泥悬浮液中溶解氧的差异,曝气开孔直径为1.0mm时,膜阻力上升速率最小,活性污泥悬浮液中溶解氧浓度最大,曝气开孔直径为1.0mm的管状曝气器既能有效控制膜污染,又能给微生物提供较高的溶解氧,是较为理想的曝气器.Membrane bioreactor constructed from flat-sheet membranes was built on a lab scale to study the influences of clearance between membranes（4.0,8.0and 12.0mm,respectively）,air bubbling intensity and air bubbling size（tubular bubbling device with orifices of different diameter of 1.0,2.0and 3.0 mm）on the membrane fouling process.A simulated membrane bioreactor was constructed to study the bubble formation,shapes and rising between membrane clearances using clean water as permeate.The results indicated that when the membrane clearance was 4.0mm,membrane fouling rate was the smallest.Observation of the bubble formation and movement through image pickup in the simulated membrane bioreactor and image analysis revealed that when the clearance of the membranes was 4.0mm,the bubble deformed through distortion to the largest extent and emerged as cap shape,providing the largest scouring surface of the membranes.The uprising velocity of bubble was significantly reduced due to the＂wall effects＂.For the bubbling devices with different orifice diameter,the one with 1.0 mm orifice diameter efficiently reduced the membrane fouling rate,simultaneously providing higher concentration dissolved oxygen for the aeration MBR.

关 键 词：平板膜生物反应器 膜污染 膜间距 气泡形态 曝气孔径 

分 类 号：X703.1[环境科学与工程—环境工程]