A pressure exchanger is a rotary ceramic energy-recovery device that transfers hydraulic pressure from the SWRO brine stream to incoming low-pressure feed water, with >97% efficiency. The dominant brand is the ERI PX series. A rotor spins inside a ceramic sleeve. As it rotates, ducts alternately connect high-pressure brine to a column of feed water — pressurizing it almost without losses — then connect low-pressure feed to depressurized brine for discharge. A pressure exchanger cuts SWRO energy consumption from ~6 kWh/m³ down to 2.5–3 kWh/m³, paying back its capital cost in 12–24 months on most commercial systems. Modern ERI PX-Q series devices achieve 97.5–98% net energy transfer efficiency in commercial SWRO duty. PX is isobaric — it transfers pressure directly with no rotating energy conversion. Turbochargers (FEDCO HPB) convert brine pressure to shaft work then back to pressure, losing 10–15% efficiency but with no moving electrical parts. PX devices tolerate fine particulate but require pretreatment to <10 µm. Coarse grit damages the ceramic sleeve. 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.Pressure Exchanger (PX)
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Frequently Asked Questions
How efficient is an ERI PX?
What's the difference between PX and turbocharger ERD?
Can a PX handle particulates in brine?
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