Our FILMTEC™ high rejection brackish reverse osmosis membrane delivers the industry's most reliable low energy solutions. Advanced membrane technology and automated fabrication allow these elements to consistently deliver the highest rejection rates with the highest production capacities that equipment suppliers, water treatment dealers, and residential customers can rely on. These heavy-duty large output brackish membranes deliver excellent performance in terms of flux, salt and organics rejection, and microbiological resistance, and they can operate over a pH range of 2 to 11, are resistant to compaction and are suitable for temperatures up to 45°C. Their performance remains stable over many years even under harsh operating conditions.
MEM-BW30-440i (11,550 GPD)
High productivity element combines the highest active membrane area (440 ft²) in the industry with the proven rejection and reliability of the BW series. Designed to minimize capital expenses in high-purity applications without increasing operating flux. Includes iLEC interlocking endcaps which reduce operating costs and risk of o-ring leaks that can cause poor water quality.
Polyamide Thin-Film Composite
Maximum Operating Temperature
Maximum Operating Pressure
600 psig (41 bar)
Maximum Pressure Drop
15 psig (1.0 bar)
pH Range, Continuous Operation
pH Range, Short-Term Cleaning
Maximum Feed Flow
85 gpm (19 m³/hr)
Maximum Feed Silt Density Index
Free Chlorine Tolerance
< 0.1 ppm
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.
These membranes may be subject to drinking water application restrictions in some countries: please check the application status before use and sale.
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.
FILMTEC Corporation is the leading manufacture of reverse osmosis and nanofiltration membrane elements for industrial, municipal, commercial, and home drinking water treatment and purification, as well as for other specialty applications. The company was incorporated in 1977 and is headquartered in Minneapolis, Minnesota. FILMTEC Corporation is a subsidiary of The Dow Chemical Company and part of Dow's Water & Process Solutions business group.