SWRO (Seawater Reverse Osmosis)
Mit Water designs and fabricates seawater reverse osmosis (SWRO) systems for desalination of seawater and highly saline brackish water into fresh water suitable for drinking, irrigation and industrial use. SWRO is the most energy-efficient and widely deployed desalination technology globally.
Working Principle
Seawater is pressurised to 55-70 bar using high-pressure pumps and fed to spiral-wound SWRO membrane elements. The semi-permeable polyamide membrane allows water molecules to pass through while rejecting over 99% of dissolved salts. The desalinated water (permeate) is collected while the concentrated brine is discharged. Energy recovery devices capture pressure energy from the brine stream and transfer it to the incoming feed, reducing overall energy consumption by up to 60%.
System Configuration
A complete SWRO system includes intake screening, pre-treatment (MMF or UF), cartridge filters, high-pressure pumps, SWRO membrane pressure vessels and elements, energy recovery devices, permeate flushing and CIP systems, post-treatment (remineralisation and disinfection), and a PLC-based control panel. All high-pressure components are constructed from super duplex or 316L stainless steel.
SWRO systems are deployed worldwide for seawater desalination:
- Municipal drinking water supply for coastal communities
- Resort and island water supply
- Industrial process water in coastal facilities
- Power plant cooling and boiler feed water
- Offshore platform and marine vessel fresh water supply
- Irrigation water in water-scarce coastal regions
- Emergency and humanitarian water supply
Technical Parameters
| Capacity | 10 to 10,000 m3/day per unit |
| Feed TDS | 35,000 to 45,000 mg/L (seawater) |
| Permeate TDS | Below 500 mg/L |
| Salt Rejection | 99.2% to 99.8% |
| Recovery Rate | 35% to 50% |
| Operating Pressure | 55 to 70 bar |
| Energy Consumption | 2.5 to 4.0 kWh/m3 (with ERD) |
| High-Pressure Materials | Super duplex SS or SS316L |