Membrane fouling suppression using intermittent electric current with low exposure time in a sequencing batch membrane bioreactor
Autor: | María Ángeles Lobo-Recio, Flávio Rubens Lapolli, Leonardo Dalri-Cecato, Hioná Valéria Dal Magro Follmann, Emerson Souza, Tiago José Belli, André Aguiar Battistelli |
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Rok vydání: | 2020 |
Předmět: |
Materials science
Process Chemistry and Technology medicine.medical_treatment Membrane fouling 02 engineering and technology 010501 environmental sciences 021001 nanoscience & nanotechnology Membrane bioreactor Electrochemistry Pulp and paper industry 01 natural sciences Pollution Electrocoagulation Anode Yield (chemistry) medicine Chemical Engineering (miscellaneous) Electric current 0210 nano-technology Waste Management and Disposal Effluent 0105 earth and related environmental sciences |
Zdroj: | Journal of Environmental Chemical Engineering. 8:104018 |
ISSN: | 2213-3437 |
DOI: | 10.1016/j.jece.2020.104018 |
Popis: | This study assessed for the first time the use of intermittent electric current with low exposure time in a sequential batch membrane bioreactor (SB-MBR) aiming at reducing the membrane fouling and improving the treatment performance. The SB-MBR was initially operated without electric current application (control period) and, subsequently, using the electric current density of 10 A m−2 and intermittent exposure mode of 6 min ON/30 min OFF (1.2 h d−1). Compared to the control period, the mixed liquor filterability improved substantially when the electrocoagulation was applied, resulting in a membrane fouling rate 65% lower. This better filterability condition was attributed to the improvement of the floc formation process, which resulted in larger floc size and lower sludge volume index. The biomass growth was positively impacted by the electrochemical process, resulting in a higher sludge yield coefficient. The reactor performance regarding COD and NH4+-N removal was not influenced by the electric current application, exhibiting efficiencies above 99% in both experimental periods. On the other hand, the phosphorus concentration in the reactor effluent decreased as the electrocoagulation was applied, increasing its average removal efficiency from 62% (control period) to 89%. The anodic dissolution rate was estimated at 1.28 g d−1, considerably lower than the values reported in other studies regarding EBRM running in continuous mode. Thus, it can be inferred that the integration of the electrochemical process with SB-MBR using low exposure mode is an interesting alterative to reduce the membrane fouling, extend the anode lifespan and improve the reactor performance. |
Databáze: | OpenAIRE |
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