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Updated: Jul 12, 2026
10:19
Three-Dimensionally Printed Microfluidic Cross-flow System for Ultrafiltration/Nanofiltration Membrane Performance Testing
Published on: February 13, 2016
Effect of membrane character and solution chemistry on microfiltration performance
S R Gray1, C B Ritchie, T Tran
1Institute of Sustainability and Innovation, Victoria University, PO Box 14428, Melbourne, Victoria 8001, Australia. stephen.gray@vu.edu.au
Water Research
|August 28, 2007
Summary
Natural organic matter (NOM) fouling in low-pressure membranes is complex. Hydrophilic membranes show better flux recovery, but backwashing efficiency decreases over time, with specific organic compounds acting as a "glue" for fouling.
Area of Science:
- Environmental Science
- Water Treatment Technology
- Membrane Science
Background:
- Natural organic matter (NOM) significantly impacts membrane fouling in water treatment.
- Understanding NOM's role is crucial for predicting and mitigating low-pressure membrane performance degradation.
Purpose of the Study:
- To investigate the influence of natural organic matter (NOM) on low-pressure membrane fouling.
- To compare the performance of different hollow fibre membranes with varying surface characteristics.
- To evaluate the effectiveness of backwashing and identify factors affecting fouling mitigation.
Main Methods:
- Utilized an experimental apparatus with automatic backwashing and extended filtration runs.
- Compared filtration of two surface waters using three hollow fibre membranes (hydrophilic and hydrophobic).
- Analyzed the effect of NOM concentration and solution pH on membrane flux and backwashing efficiency.
Main Results:
- Hydrophilic membranes exhibited superior flux recovery post-backwashing compared to hydrophobic membranes.
- Backwashing efficiency diminished with extended filtration times.
- NOM concentration and solution pH had minimal impact on membrane flux at extended filtration times due to effective backwashing.
- Significant differences in backwashing efficiency were observed between two water types for the hydrophilic membrane, not solely explained by colloidal NOM.
- A proposed mechanism suggests small molecular weight organics act as a 'glue' binding colloidal NOM to the membrane surface, forming a filter cake.
Conclusions:
- Backwashing effectively restores membrane flux, mitigating the impact of NOM concentration and pH at extended filtration times.
- The 'glue' mechanism involving specific organic compounds is critical for understanding colloidal NOM fouling.
- Alum coagulation enhances membrane performance by reducing the concentration of these 'glue' compounds, thereby improving fouling control.
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