Pretreatment RO

Pentair’s UF membrane technology is used around the world in the pretreatment for Reverse Osmosis (RO) processes, such as those applied in seawater desalination for drinking water and process water.



  • UF membranes are the preferred choice in RO pretreatment
  • Complete particle removal protects delicate RO membranes
  • Small footprint and chemicals use compared with conventional pretreatment
  • Economical choice in large-scale desalination
  • Best configurations are tailored to local (seawater) conditions

application areas

Reverse osmosis (RO) is the most cost-effective technology for producing drinking water by desalination of seawater or brackish water. As the delicate RO membranes are easily damaged by fouling and harsh cleaning chemicals, choosing the right pretreatment is important. UF membranes have been widely adopted as the alternative for conventional sand filtration as pretreatment for RO. With a much smaller footprint and lower chemicals use, UF provides much better feed water quality to the downstream RO system.

UF is generally regarded as the best pretreatment method for reverse osmosis. UF removes the particles responsible for quick fouling of RO membranes, and significantly reduces the silt density index (SDI) in desalination processes. Compared to the filtration steps in conventional pretreatment methods, and especially in long-term operations with average to bad feed water quality, UF is the most economical option for RO pretreatment.

pentair solutions

Pentair’s state-of-the-art ultrafiltration (UF) modules are used in the world’s most advanced water purification plants. The proven quality of Pentair technology delivers 100 percent certainty about safe water of the required quality in critical applications. UF is the best pretreatment method for RO processes, as it provides the most economical way to protect vulnerable RO membranes. Adding a precoagulation step can further improve the economics in terms of filtration flux, cleaning frequency and membrane life. We help OEMs, engineering consulting firms and EPC contractors to make the most of challenging drinking water projects. 

We develop innovative concepts and build pre-engineered and custom-engineered installations. The UF system is available in three different configuraitons:  X-Line system, vertical dead-end and horizontal dead-end. 

If you have any questions, please contact us.

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Shuwaikh, Kuwait


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