The DOW FILMTEC NF90-400 nanofiltration element is a high area, high productivity element designed to remove a high percentage of salts, nitrates, iron, and organic compounds such as pesticides, herbicides, and THM precursors. The high active membrane area combined with the low net driving pressure of the membrane allows the removal of these compounds at low operating pressures.
FILMTEC NF90-400 Membrane Elements
- Low energy usage reduces power consumption and costs
- Durable with good cleanability for long element life
- Thicker feed spacer delivers better tolerance of suspended solids and enables more efficient cleaning of organic material from the element
- FilmTec performance and quality
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 permeate-side backpressure at all times.
|Product||GMID||Nominal Active Surface Area ft2 (m2)||Product Water Flow Rate gpd (m3/d)||Stabilized salt rejection (%)|
|NaCI||7,500 (28.4)||85 95|
The FILMTEC™ NF90-400 nanofiltration element is a high area, high productivity element designed to remove a high percentage of salts, nitrate, iron and organic compounds such as pesticides, herbicides and THM precursors.
The high active area membrane combined with low net driving pressure of the membrane allows the removal of these compounds at low operating pressure.
Membrane Type Polyamide Thin-Film Composite
- Maximum Operating Temperature 113°F (45°C)
- Maximum Operating Pressure 600 psig (41 bar)
- pH Range, Continuous Operation 3 - 10
- pH Range, Short-Term Cleaning (30 min.) 1 - 13
- Maximum Feed Flow SDI 5
- Free Chlorine Tolerance <0.1 ppm
Ideal Applications Include:
- Production of drinking water
- Water reuse
- Industrial water demineralization