With Lewatit brand ion exchange resins and Lewabrane membrane filter elements, LANXESS is offering two premium technologies that perfectly complement each other: For example, while membrane technologies work cost-effectively with very salty water, for low-salt concentrations, fine purification down to the detection limit can be better implemented with ion exchangers. Membrane filtration and ion exchange help to extend the service life of turbines, steam generators and pipelines in industrial applications by permanently protecting them from incrustation, calcification and corrosion.
Water treatment for fertilizer manufacturers
LANXESS ion exchangers and membrane elements are also used in the new water treatment plant from the leading Egyptian fertilizer manufacturer, Alexandria Fertilizers Co. (Alexfert), in Alexandria. The brackish water with a salt content between 0.1 and 1 percent is pre-treated using reverse osmosis (RO) with a total of 228 Lewabrane B400 FR elements, and fully demineralized with Lewatit MonoPlus ion exchange resins. The combination of the two technologies not only results in the required final demineralized water conductivity of less than 0.08 μS/cm (microsiemens per centimeter) and 2 ppb SiO2 (parts per billion silicon dioxide), but also provides a stable and reliable process.
“Our membrane elements exhibit an excellent level of performance with the Nile surface water, which is difficult to treat. The measurements for retention capacity even exceed expectations,” says Alexander Scheffler, Membrane Business Director at the LANXESS Liquid Purification Technologies Business Unit. Ashraf Aly Mostafa, Project Manager at Alexfert, remarks: “Using reverse osmosis for pre-treatment means we can reduce the consumption of specific chemicals for resin bed regeneration by around 60 percent.”

Excellent retention capacity
The brackish water reverse osmosis plant is fed with canal water from the Nile. The TDS content (total dissolved solids – total amount of all inorganic and organic substances dissolved in the water) fluctuates seasonally between 300 and 550 milligrams per liter. The water is pre-treated using precipitation and flocculation, decarbonization with limewater, as well as with filtration.
From the outset, the Lewabrane RO elements have demonstrated their excellent salt retention capacity, as high as 99.76 percent (at 20°C).
For more information about LANXESS’s range of water treatment products, please visit www.lpt.lanxess.com