Replacing RO Membrane Elements

Advanced Reverse Osmosis Technology

Replacing RO Membrane Elements - Occasionally, it is necessary to replace RO membrane elements. This will be determined if necessary following trouble shooting and other remedial actions.

As with replacing O-rings, the system should be shut down and drained. Prior to installation, the new element serial numbers should be recorded indicating their intended location in the system. This is useful in comparing the membrane manufacturer’s test data with the system performance.

It may be necessary to remove both of the vessel end-caps. The elements can then be removed in their normal direction of flow. This will prevent their brine seals from jamming against the pressure vessel. The replacement elements can be inserted in the feed end of the vessel and used to push the other elements through.

The U-cup brine seals and the inter-connector O-rings can be sparingly lubricated with glycerin to aid fitting. Each inter-connector should have O-rings installed. U cup brine seals should be installed only with the open groove of the seal facing the upstream end of each element (note flow arrow on side of element which points toward the downstream end). Never put brine seals on both ends of an element.

After element replacement, any gaps should be limited with shims. The end caps can them be installed and the system started up. It should be filled with low-pressure water prior to starting the high-pressure pump. New elements should be rinsed to drain to remove any residual preservative chemicals. System operating data should be collected after the RO performance stabilizes (within 24 hours).

For further information or assistance please contact Reverse Osmosis Chemicals International on +44 (0) 161 877 2334 or e-mail info@rochemicals.com.