Response of zeta potential to different types of local membrane fouling in dead-end membrane filtration with yeast suspension

Abstract

The zeta potentials that responded to different types of local membrane fouling with yeast suspension were investigated by monitoring both local flux and local zeta potential. Experiments adopting segmentation and in situ monitoring methods during the dead-end hollow membrane filtration process were conducted. Comparing the model with experimental data, it was found that the zeta potential reflected the type of local membrane fouling. The variations in zeta potential during membrane filtration led to different performances in pore blocking, cake formation and cake compression processes. When the zeta potential decreased rapidly, pore blocking occurred. As the zeta potential dropped gradually and linearly, it led to cake filtration. Subsequently, when zeta potential stabilized cake compression occurred. Furthermore, the effect of fiber length on local fouling behavior was also studied. With an increase in fiber length, the time taken by the three segments to enter the cake layer compression stage was extended, and the difference between the zeta potential values in the three segments tended to increase.