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The SpiroPure SP-SW2521 Seawater Desalination Commercial Reverse Osmosis Membrane Replacement 2.5 x 21 is a high quality, high salt rejection replacement membrane filter cartridge. The SP-SW2521 seawater ro membrane offers an extremely high salt rejection rate, designed for compatible seawater desalination systems and high salinity applications. SpiroPure’s seawater filtration membranes are durable and reliable replacement seawater filters. Choose SpiroPure’s Seawater Desalination Membrane as a compatible replacement for the models listed below.
Sea Water Desalination RO Membrane Recovery Specifications:
- Nominal Size: 2.5" x 21"
- Certification: NSF/ANSI/CAN 61
- Salt Rejection Rate: 99.5%
- Average Permeate ±15%: 270 GPD @ 800 PSI
- Feedwater NaCl Test Concentration: 32,000 ppm
- Fresh Water Test Recovery Rate: 4%
- Feed Spacer: 28 mil
- Maximum Recommended NaCl: <40,000 ppm
- Maximum Operating Pressure 1,000 PSI
SP-SW2521 High Rejection Membrane common applications:
- Seawater desalination
- Marine applications
- On-board watermakers for drinking water from seawater
- Watermaker RO Systems
- Yachts, boats, cruise ships, off-shore platforms, resorts
SW salt water/seawater membrane compatible model numbers:
- SE1-2521
- Dupont Filmtec SW30-2521
Additional Information
Seawater Membranes Are Shipped Wet
An important industry practice for seawater desalination RO membranes is to have them "shipped wet." After being tested to industry standards, our membranes are preserved for protection during shipping and for future use. The preservative is food-grade, and is found within the membrane itself and not in the air-tight packaging. The preservative creates a moist environment for the filter media, allowing the permeability and performance to be maintained by preventing biological growth during storage as well as providing a longer shelf-life of one-year from the manufacturing date printed on the package.
FAQs on 2521 Seawater Filters
What is a 2521 seawater membrane used for?
A 2521 seawater RO membrane reduces dissolved salts in compatible desalination systems. The SpiroPure SP-SW2521 is designed for marine watermakers and commercial seawater treatment applications. Drinking-water suitability depends on the complete treatment system, operation, and water-quality verification.
Is the SpiroPure SP-SW2521 compatible with FilmTec SW30-2521?
The SpiroPure SP-SW2521 is listed as a compatible replacement for select DuPont FilmTec SW30-2521 and Axeon SE1-2521 applications. Its nominal size is 2.5 × 21 inches. Confirm housing dimensions, seals, pressure ratings, and system operating requirements; nominal size alone does not establish compatibility.
What does 99.5% salt rejection mean in a seawater RO membrane?
The published 99.5% rating describes salt rejection under stated test conditions using 32,000 ppm NaCl feedwater. Actual rejection varies with feedwater and operating conditions. This rating alone does not establish that the complete system’s output is safe to drink.
What is the fresh water recovery rate for this seawater RO membrane?
The published test recovery is 4%, meaning 4% of feedwater becomes permeate under those test conditions. Actual system recovery depends on system design, feedwater, and operation. It should not be assumed to be fixed at 4% for every installation.
Why does a seawater RO membrane need high pressure?
Pressure must overcome the feedwater’s osmotic pressure to drive permeate through the membrane. The SP-SW2521’s published performance is measured at 800 PSI; its maximum operating pressure is 1,000 PSI. The maximum is a limit, not a required setting. Follow system-design requirements and use pressure-rated housings and components.
Can I use a brackish water RO membrane for seawater?
No. Use a membrane and complete system designed for seawater. The SpiroPure SP-BW2521 brackish water membrane, for example, has a maximum recommended feedwater NaCl concentration below 10,000 ppm, whereas SP-SW2521 is intended for seawater applications. Verify feedwater suitability and all system pressure ratings before selecting a membrane.
How much does the SpiroPure SP-SW2521 cost?
Check the current price and purchase options on this page. Confirm system compatibility and operating requirements before ordering. Shipping eligibility depends on your order and delivery location.
