Introduction to Industrial Nanofiltration
For industrial and municipal water treatment facilities dealing with surface water or groundwater high in organic content, the Dow Filmtec (DuPont) NF270-400 stands out as a premier nanofiltration element. Known for its ability to remove a high percentage of Total Organic Carbon (TOC) and trihalomethane (THM) precursors, this membrane is an industry benchmark for clean, high-quality water production.
At Purecowater, we specialize in solving complex liquid filtration problems. Whether you are looking for the direct NF270-400/34i replacement or a high-performance industrial nanofiltration equivalent from our partners like LG or Veolia, understanding the specifications of this element is crucial for maintaining your system’s efficiency.
What is the NF270-400?
The NF270-400 is an 8-inch diameter, 400 square-foot active area nanofiltration element. Unlike Reverse Osmosis (RO) membranes that strip water of nearly all minerals, the NF270 is designed for “loose” separation. It targets organic contaminants, pesticides, and color, while allowing a portion of minerals (salts) to pass through.
Key Advantages
- High Organic Removal: Excellent rejection of TOC, pesticides, herbicides, and THM precursors.
- Partial Softening: Removes hardness (calcium and magnesium) while letting monovalent ions pass, preserving the water’s natural character and preventing it from becoming aggressive or corrosive to distribution piping.
- Energy Efficiency: Operates at lower pressures compared to standard RO membranes, reducing energy costs.
- Cleanability: The membrane chemistry allows for a wide pH cleaning range (1–12), aiding in the removal of biological and organic fouling.
Technical Specifications
The NF270-400 is engineered for high productivity in large-scale systems. Below are the standard performance metrics for this element type.
| Feature | Specification |
|---|---|
| Model | NF270-400 / NF270-400/34i |
| Membrane Type | Polyamide Thin-Film Composite |
| Active Performance Area | 400 ft² (37 m²) |
| Permeate Flow Rate | 12,500 GPD (47.3 m³/d) |
| Stabilized Salt Rejection | >97% (Based on specific test conditions, e.g., MgSO4) |
| Feed Spacer Thickness | 34 mil (low differential pressure) |
Note: Actual performance may vary based on feedwater conditions such as temperature, pH, and ionic strength. The “loose” nature of this NF membrane means it often passes 40-60% of monovalent salts (like Sodium Chloride) while rejecting >97% of divalent salts (like Magnesium Sulfate).
Operating Limits & Constraints
To ensure the longevity of the NF270-400 or its equivalents, operators must adhere to specific operating limits. Exceeding these parameters can lead to irreversible membrane damage or fouling.
| Parameter | Limit |
|---|---|
| Maximum Operating Temperature | 113°F (45°C) |
| Maximum Operating Pressure | 600 psig (41 bar) |
| Maximum Feed Flow Rate | 70 GPM (15.9 m³/hr) |
| pH Range (Continuous Operation) | 3 – 10 |
| pH Range (Cleaning / Short Term) | 1 – 12 |
| Free Chlorine Tolerance | < 0.1 ppm |
Ideal Applications
The unique filtration spectrum of the NF270-400 makes it the perfect solution for industries that need more than sand filtration but less stripping than Reverse Osmosis.
- Municipal Drinking Water: Reducing organics (DBP precursors) while maintaining water hardness for taste and pipe protection.
- Groundwater Treatment: Removal of colorants, pesticides, and slight softening without aggressive demineralization.
- Industrial Wastewater Reuse: Secondary or tertiary treatment to reduce COD/BOD loads before discharge or reuse.
Find the Right Membrane Solution
Whether you require the specific Dow Filmtec NF270-400 specs or a compatible equivalent from brands like LG or Suez/Veolia, Purecowater has the expertise to guide your selection. We ensure that the membrane elements we supply meet the rigorous flow and rejection standards your facility relies on.
Need a quote for replacements or looking for an equivalent solution?
References: Data sourced from Complete Water Solutions, Servapure, and Pure Aqua data sheets.