World-wide the demand for fresh water grows, while the availability decreases. Emerging technologies can offer an important contribution to future water treatment. It is fully recognised nowadays that membrane filtration has conquered a mature place in the production of drinking and industrial water. Due to the development of high-flux low-pressure ultrafiltration capillaries, the introduction of the 8” module design in combination with the world-wide accepted 8” pressure vessel design, and the development of the energy-efficient dead-end filtration a flexible unit operation is available for relative small water treatment plants in remote areas till large scale water factories.
 

The Norit XIGA™ system is an excellent system for the treatment of water with a low content of suspended solids. The 8” membrane elements are placed in standard 8" membrane housings, as commonly used for reverse osmosis. The Norit XIGA™ system was designed according to "open design approach" being the new standard for large scale ultrafiltration systems. Third parties can enter this 8" standard securing competitive membrane prices in the future for the end-user.

The Norit XIGA™ system operates in semi dead-end reducing the energy consumption significantly. The solids that are retained on the membrane surface are washed away periodically by means of a permeate backwash not involving any chemicals. Adsorbed substances can be removed by an "in situ" chemically enhanced backwash restoring the membrane to its original, clean state.
 

Norit XIGA™ systems are used for

• suspended solids content up to 50 mg/l.
  

Main references are found in:

• potable water polishing;
• process water polishing.
   

The Norit XIGA™ system uses X-Flow elements:

• 1.5 m long 8” elements with CAPFIL 0.8 or 1.5 mm ultrafiltration membranes;
• unique internal design ensuring effective and even distribution of water over the entire length and extremely efficient backwash;
• with permanent hydrophilic low-fouling ultrafiltration membranes.
   
  
  

In a semi dead-end system all the feed supplied to the systems leaves as permeate. The capacity is controlled by adjusting the transmembrane pressure.

At regular time intervals the system is subjected to a backwash to remove the retained particles. Adsorbed substances are removed by an "in situ" chemically enhanced backwash.
 
 

Norit XIGA™ systems are available as standardised, modular plug-and-play skids. The 8” membrane housings are placed horizontally resulting in very reliable and compact installations.
If desired customer-built systems can be supplied.