DOW FILMTEC TW30-4021 reverse osmosis (RO) elements offer high quality water for small commercial systems purifying less than one gallon per minute (0.2 m3/d) of RO water. In addition to high quality water and low energy costs, DOW FILMTEC membranes also deliver savings by providing long lasting and reliable performance.
Uses for TW30-4021 Membrane Elements
- High flux results in high yields;
- High rejection provides good water quality;
- 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 30 psi (2.1 bar).
- Avoid static permeate-side backpressure at all times.
|Product||Part Number||Applied Pressure psig (bar)||Permeate Flow Rate gpd (m3/d)||Stabilized Salt Rejection (%)|
|TW30-4021||80608||225 (15.5)||900 (3.41)||99.5|
DOW FILMTEC™ reverse osmosis (RO) elements offer the highest quality water for small
commercial systems purifying less than one gallon per minute (0.2 m3/d) of RO water.
- DOW FILMTEC membranes are available in a variety of sizes to meet a wide range of space requirements.
- DOW FILMTEC XLE extra low energy elements operate at the lowest pressure in the industry, resulting in lower energy costs and enabling system builders to use lower cost components.
- In addition to the highest quality water and the lowest energy costs, DOW FILMTEC membranes also deliver savings by providing the industry’s longest lasting and most reliable performance.
- Membrane Type Polyamide Thin-Film Composite
- Maximum Operating Temperature 113ºF (45ºC)
- Maximum Operating Pressure 600 psig (41 bar)
- Maximum Pressure Drop 13 psig (0.9 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
Ideal Applications Include:
Commercial Water treatment systems;food service
Medical and research institutions