Optimum operating conditions in hybrid water treatment process of multi-channel ceramic MF and polyethersulfone beads loaded with photocatalyst

The effects of water back-flushing period (FT) and polyethersulfone (PES) beads concentration loaded with titanium dioxide (TiO2) photocatalyst were investigated in a hybrid process of multi-channel ceramic MF and photocatalyst. The space between the outside of the membrane (0.4 ?m pore size) and the module inside was filled with the PES beads. UV at a wavelength of 352 nm was radiated from outside of the acryl module. A quantity of humic acid and kaolin was dissolved in distilled water and utilized here as synthetic water. As a result of FT effect, resistance of membrane fouling (Rf) was decreased when FT decreased from NBF (no back-flushing) to 2 min at BT 10 s. Therefore, the FT 2 min at BT 10 s was the optimal condition to reduce membrane fouling and to maintain high permeate flux in our hybrid process. As a result of photocatalyst PES beads concentration, Rf was minimum at 40 mg/L when photocatalyst beads concentration was changed from 50 to 5 mg/L. The highest treatment efficiency of turbidity was 97.6% at 30 g/L. However, the treatment efficiency of UV254 absorbance, which was the organic matter concentration, decreased from 83.5 to 77.3% when PES beads concentration was changed from 50 to 5 mg/L.