Ceramic Membranes
Ceramic membranes are constructed of inorganic materials and typically used in liquid filtration applications. Most ceramic membranes consist of a carrier and a membrane layer, and the most common materials used are:
- Aluminum Oxide (Al2O3)
- Titanium Oxide (TiO2)
- Zirconia Oxide (ZrO2)
- Silicon Carbide (SiC)
Ceramic membranes are extruded and sintered in high temperature furnaces at temperatures ranging from 1500°C to 2200°C.
Ceramic Membranes
Ceramic membranes are constructed of inorganic materials and typically used in liquid filtration applications. Most ceramic membranes consist of a carrier and a membrane layer, and the most common materials used are:
- Aluminum Oxide (Al2O3)
- Titanium Oxide (TiO2)
- Zirconia Oxide (ZrO2)
- Silicon Carbide (SiC)
Ceramic membranes are extruded and sintered in high temperature furnaces at temperatures ranging from 1500°C to 2200°C.
Unique Properties
Ceramic membranes offer unique advantages compared to other membrane materials:
- Higher flux
- Temperature resistant up to 800°C
- Chemically inert 0-14 pH
- High abrasion resistance
Operation
Flat Sheet Membranes
Flat sheet membranes are operated under a low vacuum, typically around 0,1 – 0,2 bar is applied to the membrane to pull the water through. Solids and other contaminants are blocked by the membrane pores and are retained on the surface. Backwash is performed periodically to dislodge and remove solids that have accumulated on the surface.
In some applications, air scouring is applied is applied to further clean the membranes continuously. Various types of spray washes can be employed to quickly and effectively remove solids from the membrane surface.
Tubular Membranes
SiC tubular membranes can be applied in crossflow, semi dead-end, and dead-end systems, depending on the application and quality of water.
Crossflow filtration gets its name because the majority of the feed flow travels tangentially across the surface of the filter. In dead-end filtration the feed is passed through a membrane and the solids are trapped in the filter. The filtrate is released at the other end.
The main driving force of crossflow- and dead-end filtration is transmembrane pressure. Transmembrane pressure is a measure of the pressure difference between the two sides of the membrane.
Backwash and CIP (Cleaning in Place) is performed periodically to dislodge and remove solids that have accumulated on the surface.
Tubular Membranes
SiC tubular membranes can be applied in crossflow, semi dead-end, and dead-end systems, depending on the application and quality of water.
Crossflow filtration gets its name because the majority of the feed flow travels tangentially across the surface of the filter. In dead-end filtration the feed is passed through a membrane and the solids are trapped in the filter. The filtrate is released at the other end.
The main driving force of crossflow- and dead-end filtration is transmembrane pressure. Transmembrane pressure is a measure of the pressure difference between the two sides of the membrane.
Backwash and CIP (Cleaning in Place) is performed periodically to dislodge and remove solids that have accumulated on the surface.
Ceramic Membrane Applications
The use of ceramic membranes is rapidly growing. Ceramic membranes can be used in many applications a.o.:
- Oil & Gas
- Marine
- Commercial Aquatic Filtration
- Acid and alkali filtration
- Surface- and ground water for potable use
- Pre-filtration for RO
- Industrial wastewater
- Food & beverage
- Pharmaceutical
The market for ceramic membranes is steadily growing and will continue to do so in the future. Today the ceramic membranes have become competitive with polymeric membranes, that have dominated the market until now.