1. Product Description

BW30-4040 is a spiral-wound modified aromatic polyamide thin-film composite brackish water reverse osmosis membrane element, with a universal standard size of 4-inch × 40-inch, fully compatible with all mainstream 4040 membrane housings on the market. Adopting advanced interfacial polymerization technology and a 34mil wide-flow anti-fouling feed spacer design, it addresses common pain points of traditional small-size RO membranes, including unstable desalination efficiency, severe concentration polarization and frequent chemical cleaning cycles.

It is suitable for raw water with TDS below 10,000ppm, capable of efficiently intercepting dissolved salts, colloids, organics, bacteria and heavy metal ions in water, while only allowing pure water molecules to pass through to produce qualified clean water. Supported by our full independent production chain, all semi-finished and finished membranes undergo 100% full-performance testing in a Class 100 dust-free workshop, delivering consistent batch performance, stable water flux and salt rejection. It serves as the standard core membrane element for small skid-mounted water treatment equipment, commercial water purification and industrial pre-desalination projects.

2. Technical Characteristics

1. Standard unified dimension: 4-inch diameter × 40-inch length, effective membrane area 78 sq. ft (7.6㎡), standard permeate flow rate of 2400 GPD (9.1 cubic meters per day under test conditions)

2. Reliable and stable desalination performance: Stabilized salt rejection ≥99.5%, minimum guaranteed salt rejection ≥99.0%, with excellent removal efficiency of silica, nitrate and organic pollutants

3. Wide chemical tolerance range: Continuous operating pH range 2.0–11.0, chemical cleaning pH range 1.0–13.0; acid and alkali alternate cleaning is available without damaging the membrane separation layer

4. Adaptable to diverse operating conditions: Applicable water temperature 5℃–45℃, maximum operating pressure 4.1MPa (600psi), maximum allowable pressure drop per element ≤15psi

5. Strict inlet water quality requirements: Maximum inlet SDI15 ≤5.0, inlet turbidity ≤1.0NTU, residual chlorine ≤0.1mg/L to avoid irreversible oxidative damage to the membrane

6. Optimized 34mil biostatic wide-flow feed spacer: Widens water flow channels, eliminates dead zones, reduces adhesion of colloids and microorganisms, and effectively mitigates concentration polarization under fluctuating raw water quality

7. Fiberglass reinforced winding shell: High mechanical strength, resistant to system pressure drop impact, supporting series connection of multiple membrane elements inside pressure vessels

3. Core Product Advantages

1. Outstanding Cost Performance & Lower Comprehensive Operating Costs

Balanced procurement cost, low-pressure operation design cuts pump energy consumption by 15% compared with ordinary RO membranes. Its long service life reduces membrane replacement frequency, significantly lowering long-term project operation expenses. Our self-owned large-scale production workshop and self-developed patented technologies eliminate intermediate markups, offering obvious price advantages for direct factory supply.

2. Strong Universal Water Quality Adaptability to All Types of Brackish Water

It is an all-round membrane element compatible with various raw water sources including groundwater, surface water and industrial reclaimed wastewater. It maintains stable performance under fluctuating raw water salinity, covering full-scenario water treatment demands for municipal, commercial and industrial sectors.

3. Superior Anti-Fouling Capacity & Extended Service Life

The membrane surface adopts hydrophilic negative charge modification to electrostatically repel charged pollutants. The wide pH cleaning window enables thorough removal of contaminants on the membrane surface. With complete pretreatment and regular maintenance, its service life reaches 3–5 years, and the chemical cleaning cycle is extended to 6–8 months.

4. Strict Quality Control & Complete Certifications

Manufactured in a dust-free clean workshop, every membrane element undergoes full testing for water flux, salt rejection and pressure aging. It complies with international drinking water safety standards ISO 20466:2024 and NSF/ANSI 61, featuring non-toxic and harmless materials with no secondary pollution to produced water. Backed by over 100 invention patents for independent optimization of membrane materials and structures, its stable performance has been verified by thousands of water treatment projects worldwide.

5. Easy Installation & High System Compatibility

The universal 4040 standard size fits all mainstream membrane housings with simple disassembly and assembly, supporting single independent replacement. It adapts to small skid-mounted, containerized and mobile water treatment equipment, shortening the construction cycle of complete sets of water treatment systems.

4. Wide Application Fields

Municipal Drinking Water Treatment

Treat high-salinity underground well water and micro-polluted surface water to produce qualified domestic drinking water, solving fresh water shortage problems in towns and rural areas.

Industrial Ultra-Pure Water Preparation

Pre-desalination for power plant boiler feed water, electronic factory cleaning water, food & beverage production water and pharmaceutical purified water, ensuring stable supply of high-purity water for production lines.

Industrial Wastewater Reuse & Zero Liquid Discharge

Deep desalination of wastewater from chemical, electroplating and printing & dyeing industries to realize water resource recycling, helping enterprises meet energy conservation and emission reduction targets.

Centralized Water Purification for Commercial & Community Use

Central water supply systems for large residential quarters, office buildings, schools, hotels and shopping malls to provide safe purified water for daily life.

Small Mobile Water Treatment Equipment

Portable emergency water supply devices, small commercial water dispensers, independent water purification systems for yachts and villas; its compact size fits limited installation spaces.

Laboratory & Small-Scale Softening Projects

Preparation of laboratory test water, small mineral water production lines, brackish water desalination for underground water in arid inland regions.

5.Frequently Asked Questions

Q1: What TDS range of raw water is BW30-4040 suitable for?

A1: This product is specially designed for brackish water, applicable to raw water with TDS ≤10,000ppm. It is not recommended for seawater desalination with salinity above 10,000ppm.

Q2: What is the normal service life of BW30-4040?

A2: With complete supporting pretreatment, regular chemical cleaning and standardized pressure control, the service life can reach 3–5 years. Missing pretreatment or long-term overpressure operation will drastically shorten its service life.

Q3: How often should BW30-4040 be chemically cleaned under normal operation?

A3: When inlet SDI ≤5.0 and raw water turbidity meets standards, chemical cleaning is required every 6–8 months. Shorten the cycle appropriately if raw water contains excessive microorganisms and colloids.

Q4: Is supporting pretreatment equipment mandatory for BW30-4040?

A4: Yes, it is mandatory. Multi-media filters, activated carbon filters and 5μm precision security filters must be equipped to control inlet SDI within 5.0 and prevent membrane fouling and oxidative damage.

Q5: What impurities can BW30-4040 effectively remove from water?

A5: It can efficiently intercept dissolved salt ions, heavy metals, colloids, bacteria, viruses, organic macromolecules, pyrogens and other various pollutants in raw water.