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[ Reverse Osmosis ]

Reverse osmosis (RO) is a purification process based on semi-permeable membranes where pressure is applied to raw water in order to overcome osmotic pressure leading to removal of ions, unwanted molecules and larger particles.

Unidro has vast experience in design, commissioning and start-up of Reverse Osmosis systems, for different applications.


After proper pre-treatment, Reverse Osmosis technology can be adopted in Demineralization plants. The process can be completed with final polishing through EDI (Electro Deionization).

Unidro integrate design is committed to achieve lower chemical consumption and lower footprint with respect to traditional Ion Exchange Technology.

Potable water

After proper pre-treatment, Reverse Osmosis technology can be adopted in Potable Water production. The process must be supplemented by disinfection and, in the case of drinking water and if necessary, remineralisation.

Water Reuse

Water reuse is gaining increasing importance in the Water Treatment sector and Reverse Osmosis can help increasing the overall recovery of Waste Water Treatment plants. Due to the special application, Unidro pays particular attention in the design operating parameters to ensure the desired performances.

Flue gas condensate treatment

Most energy big players are investing in construction/renewal of Waste-to-energy plants. In this context Unidro has supplied several Reverse Osmosis packages which allow to recover flue gas condensate in order to produce make up for closed loop circuit and osmotized / demineralized water for other users.

[ High Pressure Reverse Osmosis ]

Sea Water desalination

Interest for seawater desalination has risen due to concerns related to water scarcity. However, the design of this kind of systems includes a number of challenges such as employment of noble materials, handling of high pressures (e.g. 60-70 barg) and management of highly microbiologically active water. Unidro has references for seawater desalination both for onshore and offshore applications.

Zero Liquid Discharge

When environmental restrictions for waste water discharge are particularly demanding, ZLD (zero liquid discharge) may be considered. Concentration Reverse Osmosis can help reducing the waste water flow as much as possible before Evaporation and Crystallization to maximize the efficiency of the system. Unidro has experience in adopting the latest advancements in RO membranes technology for this special application, where feed pressures above 80 barg may be required.