It might appear that it is easy to know when to replace membrane elements in reverse osmosis systems (RO). Many companies will follow one or more of these guidelines to replace their membrane.
- Time, usually after three years (the warranty period of the membrane manufacturer)
- An increase in RO permeate conductivity as it relates to their water quality requirements
- A reduction in the permeate/product rate is directly related to water demand.
Relying on these simple limits could lead to membrane replacement prematurely. RO membrane elements can last for more than ten years, yet still provide salt rejection and permeate flow rates comparable to those they used at their startup. The membrane’s performance deterioration due to membrane age happens so slowly that it rarely plays a significant role in its life expectancy. It is often more dependent on how well the RO system has been maintained than replacement.
The RO membrane’s …