Product Information

Page 1 of 2 ™® Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow Form No. 609-00091-1008
FILMTEC™ Membranes
High Rejection, High Surface Area Brackish Water RO Element
Features The FILMTEC™ BW30-400 is the product of choice when the highest quality permeate is
required. It was the first 400 square foot membrane element on the market and continues to
be widely used in new equipment and retrofits where system capital and productivity are
• FilmTec’s superior automated manufacturing technology results in the most consistent
performance element-to-element and year-after-year.
• BW30-400 elements deliver high flow and high rejection without being chlorinated during
the manufacturing process. This is one reason why FILMTEC elements are more
durable and may be cleaned over a wider pH range (pH 1-13) than other RO elements.
• With more than a decade of proven performance, BW30-400 is the product you can rely
on for years of trouble-free operation.
Product Specifications
Product Part number
Active area
ft2 (m2)
Feed spacer
thickness (mil)
Permeate flow rate
gpd (m3/d)
Stabilized salt
rejection (%)
Minimum salt
rejection (%)
BW30-400 98650 400 (37) 28 10,500 (40) 99.5% 99.0%
1. Permeate flow and salt rejection based on the following standard conditions: 2,000 ppm NaCl, 225 psi (15.5 bar), 77°F (25°C), pH 8 and 15% recovery.
2. Flow rates for individual elements may vary but will be no more than 7% below the value shown.
3. Sales specifications may vary as design revisions take place.
4. Active area guaranteed +/-3%. Active area as stated by FilmTec is not comparable to nominal membrane area often stated by some manufacturers. Measurement
method described in Form No. 609-00434.
Figure 1 A
U-Cup Brine Seal
Fiberglass Outer Wrap End Cap Brine Product
FilmTec supplies
coupler part number
118027 with each
element. Each coupler
includes two 2-125
EPR o-rings (FilmTec
part number 102284).
Filmtec supplies
coupler part number
313198 with each
element. Each coupler
includes two 3-912
EPR o-rings (FilmTec
part number 151705).
Dimensions – inches (mm)
Product A B C
BW30-400 40.0 (1,016) 1.125 ID (29) 7.9 (201)
1. Refer to FilmTec Design Guidelines for multiple-element applications and recommended element recovery rates for various feed sources. 1 inch = 25.4 mm
2. Element to fit nominal 8.0-inch (203 mm) I.D. pressure vessel.

Membrane Type Polyamide Thin-Film Composite
Maximum Operating Temperaturea 113°F (45°C)
Maximum Operating Pressure 600 psig (41 bar)
Maximum Pressure Drop 15 psig (1.0 bar)
pH Range, Continuous Operationa 2 – 11
pH Range, Short-Term Cleaning (30 min.)b 1 – 13
Maximum Feed Flow 85 gpm (19 m3/hr)
Maximum Feed Silt Density Index SDI 5
Free Chlorine Tolerancec < 0.1 ppm a Maximum temperature for continuous operation above pH 10 is 95°F (35°C). b Refer to Cleaning Guidelines in specification sheet 609-23010. c Under certain conditions, the presence of free chlorine and other oxidizing agents will cause premature membrane failure.
Since oxidation damage is not covered under warranty, FilmTec recommends removing residual free chlorine by
pretreatment prior to membrane exposure. Please refer to technical bulletin 609-22010 for more information.
Operating Limits

Page 2 of 2 ™® Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow Form No. 609-00091-1008
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.
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.
Keep elements moist at all times after initial wetting.
If operating limits and guidelines given in this bulletin are not strictly followed, the limited
warranty 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 drop across an entire pressure vessel (housing) is 50 psi (3.4 bar).
Avoid static permeate-side backpressure at all times.
Regulatory Note These membranes may be subject to drinking water application restrictions in some
countries: please check the application status before use and sale.
FILMTEC™ Membranes
For more information about FILMTEC
membranes, call the Dow Water
Solutions business:
North America: 1-800-447-4369
Latin America: (+55) 11-5188-9222
Europe: (+32) 3-450-2240
Pacific: +60 3 7958 3392
Japan: +813 5460 2100
China: +86 21 2301 9000
Notice: The use of this product in and of itself does not necessarily guarantee the removal of cysts and pathogens from water.
Effective cyst and pathogen reduction is dependent on the complete system design and on the operation and maintenance of
the system.
Notice: No freedom from any patent owned by Seller or others is to be inferred. Because use conditions and applicable laws
may differ from one location to another and may change with time, Customer is responsible for determining whether products
and the information in this document are appropriate for Customer’s use and for ensuring that Customer’s workplace and
disposal practices are in compliance with applicable laws and other governmental enactments. Seller assumes no obligation or
liability for the information in this document. NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES OF