Effects of clearance between membranes and bubble shape upon membrane fouling in a flat-sheet membrane bioreactor |
Authors: Wang Dong, Feng Chao, Chen Yazhong*, Zhu Hao, Wang Qi and Cui Peng |
Units: Anhui Key Laboratory of Controllable Chemical Reaction and Material Chemical Engineering, School of Chemical Engineering, Hefei University of Technology, Hefei, 230009 |
KeyWords: flat-sheet membrane bioreactor; membrane fouling; membrane clearance; bubble shape; Orifice diameter |
ClassificationCode:X703.1 |
year,volume(issue):pagination: 2014,34(6):100-105 |
Abstract: |
Membrane bioreactor constructed from flat-sheet membranes was built on a lab scale to study the influences of clearance between membranes (4.0, 8.0 and 12.0 mm, respectively), air bubbling intensity and air bubbling size (tubular bubbling device with orifices of different diameter of 1.0, 2.0 and 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 4.0 mm, 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 4.0 mm, the bubble deforms through distortion to the largest extent and emerges as cap shape, providing the largest scouring surface of the membranes. The uprising velocity of bubble is 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. |
Funds: |
安徽省高等学校自然科学研究项目(KJ2012A240) |
AuthorIntro: |
王栋(1988—), 男, 安徽省安庆市人, 硕士, 主要从事膜生物反应器过程的膜污染及其控制研究. |
Reference: |
[1] Drews A. Membrane fouling in membrane bioreactors-characterisation, contradictions, cause and cures [J]. J Membr Sci, 2010, 363 (1–2):1–28. [2] Yang W, Cicek N, Ilg J. State-of-the-art of membrane bioreactors: worldwide research and commercial applications in North America [J]. J Membr Sci, 2006, 270 (2):201–211. [3] 华娟, 吴志超, 刘江峰, 等. 影响一体式平板膜生物反应器临界通量的因素[J]. 膜科学与技术, 2007, 27(6):13-16. [4] Böhm L, Drews A, Kraume M. Bubble induced shear stress in flat sheet membrane systems-Serial examination of single bubble experiments with the electrodiffusion method [J]. J Membr Sci, 2013, 437 (1):131–140. [5] Ndinisa N V, Fane A G, Wiley D E. Fouling control in a submerged flat sheet membrane system: Part I–Bubbling and hydrodynamic effects [J]. Sep Sci Technol, 2006, 41(7): 1383–1409. [6] Essemiani K, Ducom G, Cabassud C, et al. Spherical cap bubbles in a flat sheet nanofiltration module: experiments and numerical simulation [J]. Chem Eng Sci, 2001, 56(21-22):6321-6327. [7] Prieske H, Bohm L, Drews A, et al. Optimized hydrodynamics for membrane bioreactors with immersed flat sheet membrane modules[J]. Desalination Water Treat, 2010, 18(1-3):270–276. [8] 张传义, 王勇, 黄霞, 等. 一体式膜生物反应器经济曝气量的试验研究[J]. 膜科学与技术., 2004, 24(5):11-15. [9] 欧阳科, 谢珊, 刘辉. 曝气量对膜生物反应器污泥特性和膜污染的影响[J]. 中国给水排水, 2011, 27(13):19-22. [10] Fan F S, Zhou H D. Interrelated effects of aeration and mixed liquor fractions on membrane fouling for submerged membrane bioreactor processes in wastewater treatment [J]. Environ Sci Technol, 2007, 41(7):2523–2528. [11] Guglielmi G, Chiarani D, Judd S J, et al. Flux criticality and sustainability in a hollow fiber submerged membrane bioreactor for municipal wastewater treatment [J]. J Membr Sci, 2007, 289(1-2):241–248. [12] 姜韶堃, 马友光, 陶志勇. 非牛顿流体中运动气泡的形变[J]. 舰船科学技术, 2010, 32(12): 38-41. [13] Liu Z L, Zheng Y. PIV study of bubble rising behavior[J]. Powder technology, 2006, 168(1): 10-20. [14] 肖斌. 用Adobe Photoshop CS2 图像处理软件测定油膜面积[J]. 物理教师, 2008, 29(3):39-40. [15] Cui Z F, Chang S, Fane A G. The use of gas bubbling to enhance membrane processes [J]. J Membr Sci, 2003, 221(1-2):1–35. [16] 李春丽, 邢世录, 陶中兰, 等. 膜生物反应器近膜面流场特性实验研究[J]. 膜科学与技术, 2013, 33(2):63-69. [17] Krishna R, Urseanu M I, van Baten J M, et al. Wall effects on the rise of single gas bubbles in liquids[J]. Int Commun Heat Mass Transfer, 1999, 26(6):781-790. [18] Tian J Y, Xu Y P, Chen Z L, et al. Air bubbling for alleviating membrane fouling of immersed hollow-fiber membrane for ultrafiltration of river water[J]. Desalination, 2010, 260(1-3):225–230. [19] 羊寿生, 曝气的理论与实践[M]. 北京:中国建筑工业出版社, 1982. 74–78. |
Service: |
【Download】【Collect】 |
《膜科学与技术》编辑部 Address: Bluestar building, 19 east beisanhuan road, chaoyang district, Beijing; 100029 Postal code; Telephone:010-80492417/010-80485372; Fax:010-80485372 ; Email:mkxyjs@163.com
京公网安备11011302000819号