Full-Scale Microfiltration for Drinking Water: A Long-Term Performance Analysis

Area of Science:

• Environmental Science
• Materials Science
• Water Treatment Engineering

Background:

• Polymeric microfiltration membranes are crucial for drinking water treatment.
• Long-term operation can degrade membrane performance due to fouling and aging.
• Assessing membrane lifespan is vital for water treatment system sustainability.

Purpose of the Study:

• To evaluate the impact of 11 years of operation on polyvinylidene fluoride (PVDF) microfiltration membranes.
• To determine the hydraulic and separation properties after extended use.
• To establish an operational baseline for full-scale surface water treatment.

Main Methods:

• Analysis of PVDF capillary membranes (0.1 μm) from an 11-year-old full-scale drinking water treatment plant.
• Assessment of hydraulic permeability and separation efficiency.
• Monitoring of membrane resistance and transmembrane pressure.

Main Results:

• Membranes retained excellent separation efficiency, removing turbidity and microorganisms effectively.
• Hydraulic resistance increased nearly threefold, and permeability decreased by approximately 86%.
• Sustained operation required increased transmembrane pressure.

Conclusions:

• Despite reduced permeability, PVDF membranes maintained high separation performance for over a decade.
• The observed permeability loss exceeded the typical replacement threshold, indicating technical and economic justification for replacement.
• This study provides valuable data on the long-term performance of microfiltration membranes in real-world conditions.