DOW FILMTEC XFRLE-400/34i Membrane

Product Description

The DOW FILMTEC XFRLE-400/34i reverse osmosis element embodies Dow’s latest innovations in treatment of challenging waters with high biological and organic fouling tendencies such as municipal or industrial wastewater or challenging surface water.


  • Excellent fouling resistance provides long element life
  • High rejection results in excellent water quality
  • High flux reduces energy use
  • durable with good cleanability for long element life
  • Filmtec Performance and quality

General Information

Proper start-up of reverse osmosis water treatment systems is essential to prepare the membranes for operating service and to prevent membrane damage due to overfeeding or hydraulic shock. Following the proper start-up sequence also helps ensure that system operating parameters conform to design specifications so that system water quality and productivity goals can be achieved.

Before initiating system start-up procedures, membrane pretreatment, loading of the membrane elements, instrument calibration and other system checks should be completed.

Please refer to the application information literature entitled “Start-Up Sequence” (Form No. 609-02077) for more information.

Operation Guidelines

Avoid any abrupt pressure or cross-flow variations on the spiral elements during start-up, shutdown, cleaning or other sequences to prevent possible membrane damage. During start-up, a gradual change from a standstill to operating state is recommended as follows:

  • Feed pressure should be increased gradually over a 30-60 second time frame.
  • Cross-flow velocity at set operating point should be achieved gradually over 15-20 seconds.
  • Permeate obtained from first hour of operation should be discarded.

Important Information

  • Keep elements moist at all times after initial wetting.
  • If operating limits and guidelines given in this Product Information Bulletin are not strictly followed, the DOW™ FILMTEC™ Reverse Osmosis and Nanofiltration Element Three-Year Prorated Limited Warranty (Form No. 609-35010) will be null and void.
  • To prevent biological growth during prolonged system shutdowns, it is recommended that membrane elements be immersed in a preservative solution.
  • The Customer is fully responsible for the effects of incompatible chemicals and lubricants on elements.
  • Maximum pressure drops are 15 psi (1.0 bar) per element or 50 psi (3.4 bar) per multi-element pressure vessel (housing) whichever value is more limiting.
  • Avoid static permeate-side backpressure at all times.
Product Part number Active area ft2 (m2) Feed spacer thickness (mil) Permeate flow rate gpd (m3/d) Stabilized salt rejection (%) Minimum salt rejection (%)
XFRLE-400/34i 347731 400 (37) 34 11,500 (44) 99.4 99.2


Typical Solute Rejections
Silica rejection (%) Nitrate rejection (%) Ammonium rejection (%) Isopropyl alcohol rejection (%)
99.7 96.4 97 92
  • Proven fouling resistance chemistry of the DOW FILMTEC BW30XFR-400/34i operating at over 30% lower pressure
  • Large 34-mil spacer optimized for pressure drop minimization reducing the impact of fouling and enhancing the cleaning efficiency
  • Wide chemical tolerance allowing effective and efficient cleaning of biofilms, organic compounds and scale at cleaning pH from 1 to 13
  • High rejection of special solutes such as Nitrate, Ammonium or Silica
  • High integrity achieved with proprietary iLEC™ technology (interlocking end-caps), minimizing the risk of o-ring leaks that can contribute to poor water quality

Offering long term stable performance at lowest total life cycle cost. The high solute rejection make treated water suitable for reuse in a large number of applications.

Operating Limits
  • Membrane Type Polyamide Thin-Film Composite
  • Maximum Operating Temperature 113°F (45°C)
  • Maximum Operating Pressure 600 psig (41 bar)
  • Maximum Pressure Drop 15 psig (1.0 bar)
  • pH Range, Continuous Operation 2 - 11
  • pH Range, Short-Term Cleaning (30 min.) 1 - 13
  • Maximum Feed Silt Density Index SDI 5
  • Free Chlorine Tolerance <0.1 ppm
  • Industrial water demineralization
  • Production of municipal drinking water
  • Water reuse
[custom-documents] [/custom-documents]
(3 reviews) Write a Review
  • 5
    The best membrane supplier

    Posted by Michael G. on Apr 14th 2020

    shipped same delivery, thanks

  • 5
    High stock value

    Posted by Jessica N. on Nov 7th 2019

    We ordered large quantity and you were able to satisfy our need on time. Thanks!

  • 5
    Great solution for water treatment

    Posted by Bethany T. on Nov 21st 2018

    Better prices here!

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