Hits:

Indexed by:期刊论文

Date of Publication:2012-10-24

Journal:SEPARATION AND PURIFICATION TECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:100

Page Number:44-50

ISSN No.:1383-5866

Key Words:Electrocoagulation; Membrane fouling; Conductive membrane; Electric field

Abstract:Applying minute electric field on conductive membrane cathode and Fe anode effectively reduced membrane fouling in eMBR (electric field attached membrane bioreactor) by integrating electrocoagulation (EC) with electrostatic rejection of the foulants. The effect and the mechanism of electric currents on the anode corrosion and release of ferrous iron, sludge activity and fouling reduction were investigated in EC-eMBR. Comparative tests were carried out using four reactors, fed with the same influent, but operated under different electric current, constantly at 0 mA, 1 mA, 3 mA and 5 mA. Without electric current (0 mA), the membrane filtration lasted 34 days, when 3 times membrane cleaning were conducted (average 11 days/cycle). With 1 mA current, the filtration lasted 48 days with only 2 times membrane cleaning (average 24 days/cycle), indicating an optimal balanced effect of EC and electrostatic rejection on foulants. Under higher currents at 3 mA and 5 mA, 3 times membrane cleaning were required during 54 days and 47 days lasting filtration (18 days or 16.3 days/cycle), respectively. The integration of EC and electrostatic rejection extended the filtration cycle and reduced the cleaning frequency. High currents EC tends to counteract and reduce the electrostatic rejection effect of high currents electric field on foulants. The positive effects of EC included the increase in sludge activity, the decrease of both the extracellular polymeric substance (EPS) and the specific filtration resistances. (C) 2012 Elsevier B.V. All rights reserved.