Types of MBR Membranes
By: Kate Nana
Post Date: November 24th, 2025
Email:Kate@aquasust.com
1. Hollow-Fiber Membranes
Hollow-fiber membranes are the most widely used type in submerged MBR systems.
They feature high pressure resistance, good structural stability, and do not require additional support materials.
Their high packing density and relatively low manufacturing cost result in long service life.
Hollow-fiber membranes are mainly available in string (curtain) type and bundled (column) type configurations.
2. Flat-Sheet Membranes
Flat-sheet membranes consist of multiple membrane plates arranged in parallel, forming flow channels between each plate.
They are suitable for inside-out or outside-in filtration modes.
These membranes offer easy cleaning and maintenance, although their market adoption is lower than hollow-fiber membranes.
3. Ceramic Membranes
Ceramic membranes provide exceptional chemical resistance and mechanical strength, making them ideal for treating wastewater with high hardness, abrasiveness, or corrosiveness.
Common ceramic materials include alumina, titania, and silica.
Although highly durable, ceramic membranes are generally more expensive and less commonly used in standard municipal MBR systems.
4. Tubular Membranes
Tubular membranes are cylindrical and can operate in either inside-out or outside-in modes.
They have large flow channels, promoting turbulence inside the tubes, which improves anti-fouling performance and reduces pressure loss.
Tubular membranes are suitable for microfiltration, ultrafiltration, and even nanofiltration processes, especially for high-solid or viscous wastewater streams.
Membrane Materials and Key Characteristics
PVDF (Polyvinylidene Fluoride)
PVDF is the most widely used membrane material due to its balanced cost, chemical stability, and mechanical strength.
However, its anti-fouling performance is relatively weaker compared to advanced materials.
PTFE (Polytetrafluoroethylene)
PTFE membranes are more expensive but offer highly uniform pore structure and superior fouling resistance, making them suitable for complex or heavily polluted wastewater applications.
Application Scenarios and Advantages
Hollow-Fiber Membranes
High packing density
Strong pressure resistance
Low cost and long lifespan
Ideal for submerged MBR systems
Flat-Sheet Membranes
Easy to clean and maintain
Suitable for both internal and external pressure modes
Less common than hollow-fiber membranes
Ceramic Membranes
Outstanding chemical and mechanical durability
Suitable for high-hardness or corrosive wastewater
Less commonly used due to higher cost
