When to Clean Membranes

Membrane Cleaning Chemicals Product Support

In normal operation, the membrane in reverse osmosis membrane elements can become fouled by suspended solids, microorganisms and mineral scale. These deposits build up during operation and cause loss in water output or salt rejection, or both. Membrane elements should be cleaned whenever the normalized water output rate drops by 15% from its initial flow rate (the flow rate established during the first 24 to 48 hours of operation) or when salt content in in the product water rises noticeably.

It should be noted that the water output rate will drop if feedwater temperature decreases (see Temperature Correction). This is normal and does not indicate membrane fouling.

Membrane Cleaning Sequence

Acid Cleaning

Flush

Alkaline Cleaning

Flush

Sanitizing

Flush

Comparison of Fouled and Clean Membrane

This page was last updated 07/17/08