CSM RE4021-BLF

Summary

Product identification

The CSM RE4021-BLF is an ultra-low pressure grade reverse osmosis (RO) element designed for low total dissolved solids (TDS) water applications.

• General Features: Ultra-Low-Energy Consumption
• Membrane Type: Thin-Film Composite
• Membrane Material: Polyamide (PA)
• Element Configuration: Spiral-Wound, FRP Wrapping

Performance

Performance is measured under the following test conditions:

• NaCl solution: 500 mg/L
• Applied pressure: 100 psig (0.69 MPa)
• Recovery: 8%
• Temperature: 77℉ (25℃)
• pH: 6.5–7.0
• Permeate flow rate for each element may vary +25 / -25%.

General Features:

• Permeate Flow Rate: 1,200 GPD (4.5 m³/day)
• Nominal Salt Rejection: 99.2% (Minimum 99.0%)
• Effective Membrane Area: 35ft² (3.3 m²)

Operating limits

• Max. Pressure Drop / Element: 15 psi (0.10 MPa)
• Max. Pressure Drop / 240” Vessel: 60 psi (0.41 MPa)
• Max. Operating Pressure: 600 psi (4.14 MPa)
• Max. Feed Flow Rate: 18 gpm (4.09 m³/hr)
• Min. Concentrate Flow Rate: 4 gpm (0.91 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

Mechanical / hydraulic

• Model Name: RE4021-BLF
  • Length (A): 21.0 inch (533.4 mm)
  • Diameter (B): 3.9 inch (99.0 mm)
  • Inner Diameter (C): 0.75 inch (19.1 mm)
  • Outer Diameter (D/E): 1.05 inch (26.7 mm)
• Inter-Connector Part Number: SWA01050
• Brine Seal Part Number: SWA01046
• Each membrane element is supplied with one interconnector (coupler) and four O-rings.
• All RE4021 elements fit nominal 4.0 inch (101.6 mm) I.D. pressure vessels.
• The element shell is Fiber Reinforced Plastic (FRP).

General Handling Procedures

• Elements must be kept dry at room temperature (7–32°C; 40–95°F) and should not be stored in direct sunlight.
• For WET-TYPE elements, a preservative solution (1% sodium metabisulfite solution) is added to inhibit microbial growth.
• Permeate from the first hour of operation should be discarded.
• Stabilized salt rejection is generally achieved within 1–48 hours of continuous use.
• 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; incompatible chemicals may void the limited warranty.
• Permeate pressure must always be equal to or less than the feed/concentrate pressure; damage caused by permeate back pressure voids the limited warranty.
• Be aware of glass fiber strands from the FRP shell and use safety equipment during handling.

Certifications

• Certified to NSF/ANSI/CAN 61

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

Official datasheet (PDF)

PDF datasheet