Uses for BW30-400/34i Membrane Elements
- High rejection gives good water quality;
- durable with good cleanability for long element life;
- 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 DOW™ FILMTEC™ Reverse Osmosis and Nanofiltration 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 drop across an entire pressure vessel (housing) is 50 psi (3.4 bar).
- 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 (%)|
|strong>BW30-400/34i||248151||400 (37)||34||10,500 (40)||99.50%||99.00%|
The DOW FILMTEC™ BW30-400/34i element is the ultimate element for durable, high-rejection, high-productivity performance in high fouling or challenging feed conditions, enabling trouble-free operation and a low cost of water.
• Features a 34 mil feed spacer to lessen the impact of fouling on pressure drop across a vessel and enhance cleaning effectiveness.
• Offers the proven performance and high productivity of the DOW FILMTEC BW30 membrane
• Delivers a lower total cost of water by enabling lower capital and/or operating expenses compared to 365 sq. ft. elements.
• Includes iLEC™ interlocking endcaps, which reduce system operating costs and the risk of o-ring leaks that can cause poor water quality.
- 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 Operation 2 - 11
- pH Range, Short-Term Cleaning (30 min.) 1 - 13
- Maximum Feed Flow 85 gpm (19 m3/hr)
- Maximum Feed Silt Density Index SDI 5
- Free Chlorine Tolerance <0.1 ppm
Ideal Applications Include:
Industrial water demineralization
Production of municipal drinking water