LANXESS Launches New Reverse Osmosis Elements in South east ASIA
Specialty chemicals company LANXESS is offering a wide range of products and comprehensive service in two important areas of water treatment at Singapore International Water Week (SIWW), to be held July 10 to 14, 2016: Membrane technology and ion exchange. At this year’s SIWW, the company is launching for the first time in Southeast Asia its Lewabrane reverse osmosis (RO) elements with novel feedspacer.
“We succeeded in a very short time in developing a market-ready, novel feed spacer used in the membrane element. It provides for optimised flow in the RO element and thus lower energy consumption. Combining it with our proven, Lewabrane-brand reverse osmosis membrane results in high-performance products suitable for any number of applications,” explained Dr. Carsten Schellenberg, head of research and development at the membrane facility operated by the Liquid Purification Technologies (LPT) business unit in Bitterfeld, Germany.
Initially, two, new products are to be introduced: Lewabrane B400 LE ASD and Lewabrane B400 FR ASD. Optimized for applications in brackish water, these elements have standard geometries (length: 40 inches, diameter: 8 inches) and are characterised by very low energy consumption (LE = low energy) and high fouling resistance (FR = fouling resistant).
Successful development partnership
The new products in the Lewabrane line were developed as part of a cooperative research project involving LANXESS as well as regional and international partners. The feed spacers incorporated in the membrane elements are multifunctional. They create space between the membrane surfaces for fast-flowing water, support the membrane in the process and cause turbulent water flow. Although turbulent flow helps to lower salt concentrations at the surface of the membrane, and to reduce the extent of concentrate polarization, it also causes an increased pressure drop compared, for instance, to laminar flow.
The optimal design of the feed spacers therefore is of critical importance to the properties of the elements. Filaments or strands of different thickness are used for the novel feed spacers. The new product family is named after this alternating strand design (ASD).
Lower energy consumption, longer dwell times
Computational fluid dynamic (CFD) simulations had previously indicated that RO elements with ASD feed spacers would indeed be capable of achieving higher performance levels. Tests of prototypes later fabricated as part of the project confirmed these calculations.
The prototypes were shown to have a significantly lower pressure drop than standard grades and competitor products. Furthermore, the tendency towards scaling in the element was reduced. “With the new elements, we expect energy usage to decline and dwell times to be extended,” said Schellenberg, summarising the results.
Pooled competence for reverse osmosis and ion exchange
LANXESS is one of the most important suppliers for liquid separation processes worldwide. It holds a leading position in the development and production of ion exchange resins and is strongly committed to the further development of reverse osmosis membrane elements. As a single-source supplier, the company provides customers with its proven Lewatit ion exchange resins and Lewabrane reverse osmosis membrane elements.
The knowledge and experience LANXESS has gained with its Lewabrane and Lewatit grades, and its technological and applications know-how in membrane technology and ion exchange, are continuously being incorporated into LANXESS’ proprietary LewaPlus design software. It supports not only the design of reverse osmosis, ion exchange and combined systems for water treatment, but also a detailed and reliable estimation of the investment and operating costs.