Water treatment by reverse osmosis
The Liquid Purification Technologies (LPT) business unit of specialty chemicals company LANXESS is one of the most important suppliers for liquid separation products worldwide. With Lewatit® ion exchange resins and Lewabrane RO membrane elements, LPT offers two premium separation technologies for desalination and allocation of ultra-pure water.
The Lewabrane RO membrane elements family consists of spiral-wound, thin-film composite membrane elements designed specifically for water treatment applications. The RO membrane chemistry and element construction is designed to provide optimized, low-cost operation for downstream unit applications, like separate-bed or mixed-bed ion exchange units.
Most important applications for industrial water treatment are:
- Seawater desalination
- Production of boiler feed water in power stations
- Demineralization and particle removal in microchip manufacture
- Water desalination for light industry (car wash, laundries, and marine application)
- Wastewater treatment, including post membrane bioreactor (MBR) application
- Groundwater remediation and recharge
Lewabrane RO products are produced in a modern, fully automated, state-of-the-art production facility in Bitterfeld (Germany). The chemistry approach for our RO membrane places the emphasis on higher cross-linking of the polyamide layer and, therefore, higher durability to cleaning chemicals, more stable rejection of mixed ion salt solutions and lower surface charge on the membrane to reduce the fouling tendency.
- Low salt passage, typically >99,7% rejection at standard conditions in brackish water
- High flow productivity
- Improved barrier layer chemistry (lower charge and higher cross-linkage) providing lower membrane fouling rates
- More stable salt rejection during operating lifetime (as the rejection mechanism is based more on solution diffusion than ionic repulsion)
Improved organic compound rejection
- More durable to allow less frequent, more aggressive cleaning