FilmTec Corporation is a subsidiary of The Dow Chemical Company and part of the Dow Water & Process Solutions business. We make high-quality DOW™ FILMTEC™ reverse osmosis and nanofiltration elements for a wide variety of industrial, municipal, commercial and home drinking water applications. Dow also produces DOWEX™ ion exchange resins, as well as a variety of specialty water separation products.

Dow customers are primarily original equipment manufacturers of water treatment systems, engineering companies that specialize in the design and installation of water treatment systems, water service companies that operate water treatment systems for industrial and other water end users, and public and private water utilities. Our customers serve a wide range of end users including power generation and semiconductor plants, chemical and process industries, municipalities, and other commercial and consumer customers.

DOW FILMTEC™ LC LE-4040 membrane is available to meet a wide variety of customer needs in commercial applications, from producing high purity water to delivering low total system costs. Dow’s fully automated element production enables the most consistent products in the industry that minimizes the total cost of ownership of water treatment systems.

• LC LE-4040 produces high quality water with our state of the art RO membrane, using Dow’s innovative low energy proprietary technology.

Product Specifications

1. Permeate flow and salt rejection based on the following test conditions: 2000 ppm NaCl, 77°F (25°C), 15% recovery, pH 8, and applied pressure 225 psig for LC HR and 125 psig for LC LE
2. Permeate flows for individual elements may vary +/-15%.
3. For the purpose of improvement, specifications may be updated periodically.

Figure 1

1. Refer to DOW FILMTEC™ Design Guidelines for multiple-element systems
2. LC HR-4040 and LC HRLE-4040 elements fit nominal 4-inch I.D. pressure vessel.

1. Maximum temperature for continuous operation above PH 10 is 95°F (35°C).
2. Refer to Cleaning Guidelines in specification sheet 609-23010.
3. 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, Dow recommends removing residual free chlorine and other oxidants by pretreatment prior to membrane exposure. Please refer to technical bulletin 609-22010 for more information.

General Information
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.

Operation Guidelines
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 Product Bulletin are not strictly followed, the limited warranty in 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.