Vontron ULP31‑4040 RO Membrane – Ultra‑Low Pressure 4″×40″ The Vontron ULP31‑4040 RO Membrane is an ultra-low-pressure reverse osmosis element that delivers high performance in a compact format. With this Vontron RO Membrane, you get around 1,900 GPD (~7.2 m³/day) under ideal conditions, along with ~99% rejection, making it a strong choice for surface water, municipal, and low‑TDS applications. It operates at considerably lower pressure than standard membranes — thereby reducing infrastructure and energy costs. The 4″ × 40″ “4040” size ensures compatibility with common vessels and easier integration into existing RO systems. Key Features of the Vontron ULP31‑4040 RO Membrane Ultra‑low-pressure design: works at approximately two‑thirds the pressure of standard membranes. Highly stable rejection (~99.4%) with a minimum of ~99.0% under test conditions. Rated average permeate ~1,900 GPD under testing conditions. Suitable for feedwater TDS up to ~2,000 ppm NaCl (municipal, surface, or borehole). Compact 4″ diameter × 40″ length fits standard RO vessels. Robust operating limits: Max pressure ~600 psi (4.14 MPa), max feed temperature ~45 °C, feed SDI ≤ 5. Technical Specifications Parameter Value Model ULP31‑4040 Active Membrane Area ≈ 90 ft² (≈8.4 m²) Rated Permeate Flow ~1,900 GPD (~7.2 m³/day) Stable Rejection Rate ≈ 99.4% Minimum Rejection Rate ≈ 99.0% Maximum Operating Pressure ~600 psi (~4.14 MPa) Maximum Feed Temperature 45 °C Maximum Feed Flow 16 gpm (~3.6 m³/h) SDI (Silt Density Index) ≤ 5 Free Chlorine in Feed < 0.1 ppm pH Range (Continuous) 3–10 pH Range (Cleaning) 2–12 Physical Size Length ~1016 mm, OD ~99.7 mm (3.9″) Why Choose the Vontron ULP31‑4040 RO Membrane? Opting for the Vontron ULP31‑4040 RO Membrane means choosing a high‑efficiency membrane that delivers reliable water quality with reduced energy and infrastructure cost. It is ideal for customers requiring large throughput without high-pressure systems. Moreover, its compatibility with existing 4″×40″ housings makes retrofit simple, and its strong performance specs ensure long-term value in municipal or low‑TDS applications. Installation & Maintenance Tips Ensure pre‑treatment: feedwater must meet SDI ≤ 5, free chlorine < 0.1 ppm, and temperature ≤ 45 °C. On first use, flush the new membrane: 15‑25 minutes at low pressure, followed by 60‑90 minutes at full pressure — discard the first hour of permeate. Monitor key indicators: gradually check permeate flow, conductivity, and differential pressure; any drop may signal fouling or scaling. Follow chemical cleaning protocols as specified by the manufacturer. Avoid excessive chlorine exposure and maintain pH within limits. For storage or standby, keep the membrane wet or in a protective solution (e.g., 1% sodium bisulfite) to prevent microbial growth.
