Effects of spacer orientations on the cake formation during membrane fouling: Quantitative analysis based on 3D OCT imaging. (1st March 2017)

• Record Type: Journal Article
• Authors: Liu, Xin; Li, Weiyi; Chong, Tzyy Haur; Fane, Anthony G.
• Is Part Of: Water research. Volume 110(2017)
• Page Start: 1
• Page End: 14
• Publication Date: 2017-03-01
• Subjects: Membrane fouling -- Spacer orientation -- Optical coherence tomography -- 3D imaging -- Quantitative analysis; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2016.12.002
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: Spacer design plays an important role in improving the performance of membrane processes for water/wastewater treatment. This work focused on a fundamental issue of spacer design, i.e., investigating the effects of spacer orientations on the fouling behavior during a membrane process. A series of fouling experiments with different spacer orientation were carried out to in situ characterize the formation of a cake layer in a spacer unit cell via 3D optical coherence tomography (OCT) imaging. The cake layers formed at different times were digitalized for quantitatively analyzing the variation in the cake morphology as a function of time. In particular, the local deposition rates were evaluated to determine the active regions where the instantaneous changes in deposit thickness were significant. The characterization results indicate that varying the spacer orientation could substantially change the evolution of membrane fouling by particulate foulants and thereby result in a cake layer with various morphologies; the competition between growth and erosion at different locations would instantaneously respond to the micro-hydrodynamic environment that might change with time. This work confirms that the OCT-based characterization method is a powerful tool for exploring novel spacer design. Graphical abstract: Highlights: In situ characterization of the cake formation in a spacer-filled channel via 3D optical coherence tomography (OCT) imaging. Visualizing the cake layer in a spacer unit cell on a micron scale. Quantitative analysis of the effect of spacer orientation on the evolution of deposition patterns as a function of time. Quantitative analysis of the effect of spacer orientation on the local growth and erosion rates.