CSM RE2521-BLF

Summary

Product identification

The RE 2521-BLF is an ultra-low pressure RO element designed for low TDS water applications.

Specifications

• Permeate flow rate: 350 GPD (1.3 m³/day)
• Stabilized salt rejection: 99.2%
• Effective membrane area: 12 ft² (1.1 m²)
• Minimum salt rejection: 99.0%
• Permeate flow rate variation: No more than 15%
• Membrane type: Thin-Film Composite
• Membrane material: Polyamide (PA)
• Element configuration: Spiral-Wound, FRP Wrapping

Test Conditions (for stated performance):

• NaCl solution: 500 mg/L
• Applied pressure: 100 psig (0.7 MPa)
• Recovery: 8%
• Temperature: 77 °F (25 °C)
• pH: 6.5–7.0

Packaging: Elements are vacuum sealed in a polyethylene bag containing 1.0% SBS (sodium bisulfite) solution and individually packaged in a cardboard box. Each membrane element is supplied with one brine seal, one interconnector (coupler), and four o-rings. All RE2521 elements fit nominal 2.5 inch (64 mm) I.D. pressure vessels.

Mechanical / hydraulic

Operating limits

• Max. Pressure Drop / Element: 15 psi (0.1 MPa)
• Max. Pressure Drop / 240” Vessel: 60 psi (0.41 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

Design Guidelines for Various Water Sources

• 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

General Handling Procedures

• Elements must be kept dry at room temperature (7–32 °C; 40–95 °F) and not stored in direct sunlight. If the polyethylene bag is damaged, a new preservative solution (sodium bisulfite) must be added and air-tight sealed.
• 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 (one week or less), 1% by weight sodium metabisulfite solution is adequate.
• 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. Use of incompatible chemicals may void the element limited warranty.
• 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 on extracted text and may not include all figures, footnotes, or the latest revisions from the original PDF datasheet. For contractual data, please refer to the specific OEM PDF revision used on your project.

Official datasheet (PDF)

PDF datasheet