Microalgae Filtration Using an Electrochemically Reactive Ceramic Membrane: Filtration Performances, Fouling Kinetics, and Foulant Layer Characteristics
Document Type
Article
Publication Date
2-4-2020
Abstract
Electrochemical membrane filtration has proven to be successful for microbial removal and separation from water. In addition, membrane fouling could be mitigated by electrochemical reactions and electrostatic repulsion on a reactive membrane surface. This study assessed the filtration performances and fouling characteristics of electrochemically reactive ceramic membranes (a Magneli phase suboxide of TiO2) when filtering algal suspension under different dc currents to achieve anodic or cathodic polarization. The critical flux results indicate that when applying positive or negative dc currents (e.g., 1.25-2.5 mA·cm-2) to the membrane, both significantly mitigated membrane fouling and thus maintained higher critical fluxes (up to 14.6 × 10-5·m3·m-2·s-1 or 526 LMH) compared to the critical flux without dc currents. Moreover, applying dc currents also enhanced membrane defouling processes and recovered high permeate flux better than hydraulic and chemical backwash methods. Moreover, fouling kinetics and the cake layer formation were further analyzed with a resistance-in-series model that revealed many important but underexamined parameters (e.g., cake layer resistance and cake layer thickness). The cake layer structures (e.g., compressibility) were shown to vary with the electrochemical activity, which provide new insight into the biofouling mechanisms. Finally, the algogenic odor, geosmin, was shown to be effectively removed by this reactive membrane under positive dc currents (2.5 mA·cm-2), which highlights the multifunctional capabilities of electrochemically reactive membrane filtration in biomass separation, fouling prevention, and pollutant degradation.
Identifier
85079022698 (Scopus)
Publication Title
Environmental Science and Technology
External Full Text Location
https://doi.org/10.1021/acs.est.9b07022
e-ISSN
15205851
ISSN
0013936X
PubMed ID
31916753
First Page
2012
Last Page
2021
Issue
3
Volume
54
Grant
2018YFE0110600
Fund Ref
National Science Foundation
Recommended Citation
Hua, Likun; Cao, Han; Ma, Qingquan; Shi, Xiaonan; Zhang, Xuezhi; and Zhang, Wen, "Microalgae Filtration Using an Electrochemically Reactive Ceramic Membrane: Filtration Performances, Fouling Kinetics, and Foulant Layer Characteristics" (2020). Faculty Publications. 5484.
https://digitalcommons.njit.edu/fac_pubs/5484
