Reverse osmosis (RO) is a water-purification process that uses pressure to force feed water through a semi-permeable membrane, leaving dissolved salts, organics, and pathogens behind. The clean output is called permeate; the rejected concentrate is brine. A high-pressure pump pressurizes pretreated feed water against an RO membrane. Water molecules diffuse through the membrane while up to 99.7% of dissolved ions are rejected. Recovery (permeate ÷ feed) is typically 35–45% for seawater and 70–85% for brackish water. RO is the dominant desalination technology globally and the only practical way to bring seawater (35,000 ppm TDS) or high-TDS brackish water to potable quality (<500 ppm) for industrial, commercial, and municipal use. Seawater RO requires 55–70 bar (800–1,000 psi). Brackish water RO operates at 10–17 bar (150–250 psi). Tap-water RO membranes work at 3–7 bar (45–100 psi). Modern SWRO with energy recovery uses 2.5–4 kWh per cubic meter of permeate. Without an ERD, energy consumption doubles to 6–8 kWh/m³. RO rejects nearly all dissolved ions (>99%); nanofiltration rejects 80–95% of divalent ions but passes most monovalent salts, making it suitable for softening rather than desalination. ForeverPure has supplied desalination, high-pressure pumps, and energy-recovery devices to commercial and industrial customers since 2003. Contact our engineers for sizing, quotes, or technical support.Reverse Osmosis (RO)
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