The optimization of hydraulic interaction and fiber tensile strength in the hollow fiber membrane module

Abstract

Shear-enhanced membrane filtration is an effective way to mitigate membrane fouling. In this study, based on an in-suit investigation method, fiber Bragg Grating (FBG) sensing technology, the optimal module structure, the shear force distribution caused by aeration and crossflow, and the effect on fiber tensile strength are investigated. The results show that FBG sensing technology has obvious advantages in monitoring shear force distribution. Considering the effect of water inlet position, when the inlet and the aerator are in the same direction with the fiber, the shear force is superior to that the inlet and the aerator is perpendicular. Moreover, in the case of crossflow, a low aeration rate has a significant promotion effect on the range and value of the shear force in the membrane module. It was also found that the interaction between aeration and crossflow does not always improve the shear force, but also had negative influence on shear force enhancing. Besides, shear force is mainly located at height of 0.3–1.2 m in the membrane module, and the fiber tensile strength would be shifted in different hydraulics conditions.