Hollow fiber membrane integrity warning device based on laser extinction particles detection technology

Abstract

The breakage of hollow fiber membrane modules for the water treatment will re-pollute water and even compromise public health. In this study, an on-line warning and detection device based on the principle of laser extinction technology is put forward. The different particles such as solid particles and micro-bubbles in the permeate can be used as the tracer. The results indicated that the constant reference voltage Er constant at 2.3553 ± 0.0025 V when the membrane module was integrated; Once there is a breakage in the membrane module, the solid particles in the permeate will lead to an overall drop in voltage Eu, and the micro-bubbles will form a voltage pulse Ep as a special warning. The detection limit of turbidity is 0.12 NTU and the detection limit of the micro-bubble is about 30 μm with bubble aggregation bend tubes. The correlation coefficient of the voltage and the turbidity in permeate was 0.9722, and micro-bubbles detected by the device have the same trend with the particle counter. As a result of these findings, the extinction method does not need to add tracer particles, no background effect, and can detect the permeate on-line with the potential to install in every module. It may potentially prove to be a viable treatment option for the warning of hollow fiber membrane integrity.