8040 vs. 4040 RO Membrane: Key Differences, Applications & Pricing

Mar 29，2025 by Walchin

8040 vs. 4040 RO Membrane: Key Differences, Applications & Pricing

Reverse osmosis (RO) membranes are critical components in water treatment systems, used for seawater desalination, industrial pure water production, and food/beverage processing. Among the most common sizes are the 8040 RO membrane and 4040 RO membrane, which differ significantly in capacity, size, and applications.

This guide compares their specifications, pricing, and ideal use cases to help you select the right membrane for your needs.

1. Key Differences Between 8040 and 4040 RO Membranes

1.1 Size & Physical Dimensions

Specification 8040 RO Membrane 4040 RO Membrane
Diameter 8 inches (203 mm) 4 inches (102 mm)
Length 40 inches (1016 mm) 40 inches (1016 mm)
Membrane Area 365–400 sq. ft. 85–100 sq. ft.

Why It Matters:

  • The 8040 membrane has 4x the surface area of the 4040, enabling higher water output.

  • The 4040 membrane is more compact, suited for smaller systems.

1.2 Performance Comparison

Feature 8040 RO Membrane 4040 RO Membrane
Water Output 2,000–10,000 gallons/day 600–2,400 gallons/day
Service Life 3–5 years 2–4 years
Pressure Range 150–300 psi 100–200 psi

Key Takeaway:

  • The 8040 is ideal for high-capacity industrial systems, while the 4040 fits small-scale commercial or residential use.

2. Application Scenarios

2.1 8040 RO Membrane Uses

✔ Large-Scale Industrial Systems

  • Power plants, petrochemical refineries, pharmaceuticals.

  • Municipal seawater desalination & wastewater treatment.

  • Beverage production (e.g., bottling plants).

Recommended Product:
BW-8040-HF Anti-Fouling RO Membrane – High-performance, anti-scaling design for industrial use.

2.2 4040 RO Membrane Uses

✔ Small to Medium Systems

  • Laboratories, hospitals, small factories.

  • Hotels, restaurants, cafes.

  • Residential/commercial under-sink RO systems.

Recommended Product:
TW-4040-FR Anti-Pollution RO Membrane – Compact, low-maintenance filtration for purified water.

3. Pricing Comparison

Membrane Type Price Range (USD) Factors Affecting Cost
8040 RO Membrane 500–1,500 Brand, salt rejection rate, anti-fouling features.
4040 RO Membrane 200–600 Flow rate, durability, compatibility.

Cost-Saving Tip:

  • For high-volume needs, the 8040 offers better long-term value.

  • For smaller systems, the 4040 is more budget-friendly.

4. How to Choose the Right RO Membrane?

Consider these factors:

  1. Water Demand – Match membrane capacity (e.g., 8040 for >2,000 GPD).

  2. Water Quality – High TDS? Opt for anti-scaling RO membranes.

  3. Space Constraints – 4040 fits tighter spaces.

  4. Budget – Balance upfront cost vs. lifespan.

5. FAQs

Q: Can I use a 4040 membrane for seawater desalination?
A: Yes, but only for small-scale systems. For large projects, use seawater desalination reverse osmosis membranes.

Q: Which lasts longer, 8040 or 4040?
A: The 8040 typically lasts 3–5 years vs. 2–4 years for the 4040 due to its larger filtration area.

6. Conclusion

  • 8040 RO Membrane: Best for industrial/high-capacity systems (e.g., BW-8040-HF).

  • 4040 RO Membrane: Ideal for small commercial/residential use (e.g., TW-4040-FR).

Need Help Selecting? Consult an RO specialist to match your water quality and volume requirements!