CSM RE2521-BE

Summary

Product Identification

The RE 2521-B E is a high-productivity reverse osmosis (RO) element designed for brackish water applications.

• Permeate flow rate: 300 GPD (1.1 m³/day)
• Stabilized salt rejection: 99.7%
• Effective membrane area: 12 ft² (1.1 m²)
• Minimum salt rejection: 99.4%
• Membrane type: Thin-Film Composite
• Membrane material: Polyamide (PA)
• Element configuration: Spiral-Wound, FRP Wrapping

Performance Test Conditions: The stated product performance is based on data taken after 30 minutes of operation at the following test conditions:

• 2,000 mg/L NaCl solution at 225 psig (1.5 MPa) applied pressure
• 15% recovery
• 77 °F (25 °C)
• pH 6.5 – 7.0

Dimensions: The RE 2521-BE element has the following nominal dimensions:

• Length (A): 21.0 inch (534 mm)
• Diameter (B): 2.5 inch (64 mm)
• Interconnector end piece length (C): 0.75 inch (19.1 mm)
• Interconnector insertion depth (D): 1.1 inch (28 mm)
• Brine seal width (E): 1.1 inch (28 mm)

All RE2521 elements fit nominal 2.5 inch (64 mm) I.D. pressure vessels. Each element comes with one brine seal, one interconnector (coupler), and four o-rings.

Part Numbers:

• Element: 40000305
• Interconnector: 40000223

Packaging: All elements are vacuum sealed in a polyethylene bag containing 1.0% SBS (sodium bisulfite) solution and individually packaged in a cardboard box.

Operating Limits

• Max. Pressure Drop / Element: 15 psi (0.1 MPa)
• Max. Operating Pressure: 600 psi (4.14 MPa)
• Max. Feed Flow Rate: 6 gpm (1.36 m³/hr)
• Min. Concentrate Flow Rate: 1 gpm (0.23 m³/hr)
• Max. Operating Temperature: 113 °F (45 °C)
• Operating pH Range: 2.0–11.0
• CIP pH Range: 1.0–13.0
• Max. Turbidity: 1.0 NTU
• Max. SDI (15 min): 5.0
• Max. Chlorine Concentration: < 0.1 mg/L

Feed Water Guidelines

Design Guidelines for Various Water Sources (Flux in gfd):

• Wastewater Conventional (SDI < 5): 8–12 gfd
• Wastewater Pretreated by UF/MF (SDI < 3): 10–14 gfd
• Seawater, Open Intake (SDI < 5): 7–10 gfd
• Seawater, Beach Well (SDI < 3): 8–12 gfd
• Surface Water (SDI < 5): 12–16 gfd
• Surface Water (SDI < 3): 13–17 gfd
• Well water (SDI < 3): 13–17 gfd
• RO permeate (SDI < 1): 21–30 gfd

Saturation Limits (Using Antiscalants):

• Langlier Saturation Index (LSI): < +1.5
• Stiff and Davis Saturation Index (SDSI): < +0.5
• CaSO₄: 230% saturation
• SrSO₄: 800% saturation
• BaSO₄: 6,000% saturation
• SiO₂: 100% saturation

Handling and Storage

• Elements contained in the boxes must be kept dry at room temperature (7–32°C; 40–95°F) and should not be stored in direct sunlight.
• If the polyethylene bag is damaged, a new preservative solution (sodium bisulfite) must be added and air-tight sealed to prevent drying and biological growth.
• Permeate from the first hour of operation should be discarded to flush out the preservative solution.
• Elements should be immersed in a preservative solution during storage, shipping, and system shutdowns to prevent biological growth and freezing. The standard storage solution contains 1% by weight sodium bisulfite or sodium metabisulfite (food grade). For short term storage (i.e., one week or less), 1% by weight sodium metabisulfite solution is adequate for preventing biological growth.
• Keep elements moist at all times after initial wetting.
• Avoid excessive pressure and flow spikes.
• Only use chemicals compatible with the membrane elements and components.
• Permeate pressure must always be equal to or less than the feed/concentrate pressure. Damage caused by permeate back pressure voids the element limited warranty.

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Disclaimer: This summary is based solely on the extracted text and may not include all figures, footnotes, or the latest revisions present in the official PDF datasheet. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

PDF datasheet