Reverse Osmosis Membranes
CM Aquatechnik supplies high-rejection thin-film composite (TFC) reverse osmosis membranes from DOW FILMTEC, TORAY, and Hydranautics — three of the world's leading membrane manufacturers. Available in
Technical Specifications
| Membrane Type | Thin-Film Composite (TFC) polyamide |
| Sizes Available | 2.5" × 40", 4" × 40", 8" × 40" |
| Salt Rejection (BWRO) | Up to 99.7% NaCl |
| Salt Rejection (SWRO) | Up to 99.8% NaCl |
| Operating Pressure (BWRO) | 10 – 20 bar |
| Operating Pressure (SWRO) | 55 – 70 bar |
| Max. Temperature | 45 °C |
| pH Range (operation) | 2 – 11 |
| pH Range (cleaning) | 1 – 13 |
| Max. Chlorine Tolerance | < 0.1 ppm (continuous) |
| Brands Available | DOW FILMTEC · TORAY · Hydranautics |
Key Features
- NaCl rejection up to 99.8% for seawater applications
- Consistent permeate quality across the full operating range
- High boron rejection available (B-series elements)
- Low fouling membranes for high-turbidity feed water
- Compatible with all standard 4" and 8" pressure vessels
- Full technical datasheets and performance tables supplied
Applications
- Seawater desalination (SWRO)
- Brackish water desalination (BWRO)
- Drinking water production
- Industrial process water
- Boiler feed water demineralisation
- Food and beverage water treatment
Product Overview
CM Aquatechnik supplies high-rejection thin-film composite (TFC) reverse osmosis membranes from DOW FILMTEC, TORAY, and Hydranautics — three of the world’s leading membrane manufacturers. Available in standard 2.5″, 4″, and 8″ × 40″ spiral-wound configurations for seawater, brackish water, and tap water applications.
Our engineers select the optimal membrane element based on your feed water salinity, temperature, recovery target, and required permeate quality. We supply elements from our warehouse in Neuss, with availability confirmed in each quotation, and can supply custom quantities for large-scale projects.
Membrane Technology
TFC membranes consist of three layers: a polyester support web, a microporous polysulfone interlayer, and an ultra-thin polyamide barrier layer that performs the actual separation. This design achieves salt rejection up to 99.8% while maintaining high water flux.
Frequently asked questions
How do I choose the right reverse osmosis membrane?
The choice depends on feed water salinity, temperature, recovery target and the required permeate quality. Brackish water (BWRO) elements typically operate at 10 to 20 bar, while seawater (SWRO) elements operate at 55 to 70 bar; low fouling elements suit high-turbidity feed water and B-series elements offer high boron rejection. Our engineers select the optimal element for your conditions.
Which membrane sizes are available and will they fit my existing pressure vessels?
We supply spiral-wound elements in 2.5″, 4″ and 8″ × 40″ sizes from DOW FILMTEC, TORAY and Hydranautics. The elements are compatible with all standard 4″ and 8″ pressure vessels, so they can generally replace existing elements of the same size. Full technical datasheets and performance tables are supplied to help you compare options.
How can I extend the service life of my RO membranes?
Polyamide TFC membranes are sensitive to oxidants, so continuous chlorine exposure must be kept below 0.1 ppm, usually by dechlorination ahead of the RO stage. Operate within the permitted limits of 45 °C and pH 2 to 11, and clean the membranes within pH 1 to 13 when normalised performance declines. Effective pre-treatment against fouling and scaling is the most important factor for a long membrane life.
What information do you need for a quotation?
Please send us your feed water analysis (TDS or conductivity, hardness, silica, iron, turbidity or SDI), the water temperature, the required permeate flow and quality, your recovery target and the number and size of elements required. If you are replacing existing membranes, the current brand and model designation is also helpful. Send us your requirements and we will prepare a proposal within 48 hours.
