Toray’s New RO Membrane Element Recovers Twice as Much Water

Toray Industries, Inc. has developed a new small-sized reverse osmosis (RO) membrane element with dramatically improved water recovery.

Highly efficient water generation with energy saving is achieved with a technology that limits the resistance of feed water and purified water flowing through the RO membrane to the minimum, thus boosting the velocity of the flow of feed water. Toray will carry out global demonstrations to expand the scale and apply the technology in large-scale, industrial use RO membrane elements.

RO membrane elements are used in the purification of various types of water, and technological developments to further improve water recovery performance are required to respond to water problems that are worsening around the world every passing year.

An RO membrane element consists of an RO membrane sandwiched between the main elements of permeate side channel material and feed side channel material. To boost water recovery, it is necessary to lower the flow resistance of the permeate side flow channel and reduce ion concentration on the RO membrane surface.

Toray applied its fluid analysis, structural analysis technology and fiber processing technology it has cultivated over the years to develop the new channel material. The company succeeded in expanding the channels by forming in the striped shape, while maintaining the required pressure resistance with fine and precise molding of the molten resin. The technology reduces flow resistance on the permeate side by 50%.

When the RO membrane element is operated with improved water recovery, ion concentration on the surface of the RO membranes rises resulting in diminished separation performance. By making full use of fluid analysis, Toray succeeded in developing a new feed side channel material that is thinner and has a less number of nodes so that it can increase the flow velocity of feed water to more than twice and reduces ion concentration on the RO membrane surface by more than 30% compared with before.

By combining the above two innovative technologies, Toray succeeded in improving water recovery by as much as twofold compared with existing RO membrane elements of various sizes.

In the Toray Group Sustainability Vision announced in July 2018, Toray is contributing to solving the water scarcity faced by the world, and reducing burden on the environment by utilizing water treatment membrane technology as its mission.

Toray plans to exhibit the RO membrane element using these technologies at 2019 WQA Convention & Exposition, a tradeshow for RO products used in water purifiers from April 23rd to 25th in Las Vegas, U.S.