Point-of-use reverse osmosis element design, specifically the distribution of feed water to the membrane, has remained somewhat static since the introduction of thin layer/film composite (TLC) or non-cellulose membranes. Most reverse osmosis systems, depending on design and operating conditions, dispense 70 to 90% of feed water to the drain. Many RO systems use a similar membrane and distribute water through the element in the same manner, so there is little opportunity to increase the system’s efficiency.
Attempts to increase efficiencies of the system have related to either adjustments in the size of reject flow controllers or modifications to ancillary components, such as storage tanks, of the reverse osmosis system. Both options have advantages and disadvantages, but essentially attempt to mitigate the inefficiencies on the back end that are caused by the fundamental design of the reverse osmosis element.
In order to accurately address the efficiency issues of reverse osmosis membranes, Pentair developed the GRO. This new reverse osmosis membrane increases efficiency and boasts a 50% recovery rate without disrupting rejection performance or daily production rate of the element. It features integrated push fit connections and can easily be retrofitted into existing equipment. The GRO comes in three different GPD models: the 36, 50, and 75. Each is NSF/ANSI certified to Standard 58 for materials and structural integrity in addition to NSF list component performance claims. Its innovative element design integrates a 100% dry membrane to help maximize its lifespan and provide enhanced performance to the end user. It has two-and-a-half times the recovery over standard reverse osmosis elements, high rejection stability at high input and an enhanced rejection performance.