Skip to Content
  1. All products
  2. Replacement Filters & Cartridges
  3. Commercial RO Membranes
  4. Vontron LP21-4021 Commercial Osmosis Membrane Element
  5. Commercial RO Membranes
Pricelist: AKV Estonia Pricelist
Pricelist: AKV Estonia Pricelist

Vontron LP21-4021 Commercial Osmosis Membrane Element

The Vontron LP21-4021 is a compact, high-efficiency low-pressure reverse osmosis membrane element engineered for commercial water purification and demineralization systems. Built with an aromatic polyamide thin-film composite (TFC) barrier layer and an active filtration surface area of 3.3 m2 (36 sq ft), it is designed specifically for standard 4021 pressure vessels (4" diameter by 21" length). It provides effective removal of dissolved mineral salts, total organic carbon (TOC), silica (SiO2), and heavy metals, making it an optimal solution for point-of-use commercial equipment, food and beverage preparation, laboratories, and light industrial applications.

152.89 € 152.89 € (Tax included)
152.89 € (Tax included)

Add to cart
Buy now
Terms and Conditions
Documents
Product Data Sheet ULP21-4021.pdf

Internal Reference: 256060
Barcode: 1872025007192

Operating reliably on tap, municipal, underground, and surface water supplies with salt concentrations up to 2,000 ppm, the LP21-4021 delivers a steady permeate output of 3.6 to 4.3 m3/day (approx. 950–1,100 GPD / 0.15–0.18 m3/h) with a nominal salt rejection of up to 99.5%. The element features a durable spiral-wound configuration enclosed in a rigid fiberglass outer wrap with molded ABS end caps, an integrated brine seal, and standard 19.1 mm permeate connector stubs. Designed to operate safely under working pressures up to 41.4 bar and supporting chemical CIP cleanings across an extended pH range of 1 to 13, it guarantees long service life and reliable demineralization performance.

Technical information

Here are most important bullet points about this product.

  • Energy-Efficient Demineralization: Operates at low feed pressures to reduce high-pressure pump energy consumption and component fatigue.
  • High Rejection Efficiency: Polyamide composite structure delivers up to 99.5% stabilized rejection of dissolved salts, silica, and trace organic matter.
  • Compact 4021 Form Factor: Shorter 533 mm (21-inch) length fits standard compact 4-inch housings in space-restricted commercial setups.
  • Broad Chemical & Cleaning Tolerance: Maintains stability across an operating pH range of 2 to 11 and withstands rigorous CIP sanitization cycles from pH 1 to 13.
  • Durable Outer Construction: Heavy-duty fiberglass outer casing and molded end caps provide structural integrity under continuous hydraulic pressure.
  • Direct Drop-In Fit: Standard 19.1 mm (0.75-inch) permeate tube design ensures compatibility with commercial RO systems and 4021 membrane pressure vessels.
  • Product Type: Low-Pressure Commercial Reverse Osmosis Membrane Element
  • Brand / Model: Vontron / LP21-4021
  • Membrane Chemistry: Polyamide Thin-Film Composite (TFC), Spiral-Wound
  • Active Membrane Area: 3.3 m2 (36 sq ft)
  • Nominal Permeate Flow Rate: 3.6 m3/day (950 GPD / approx. 0.15–0.18 m3/h)*
  • Stabilized Salt Rejection: 99.5% (Minimum: 99.3%)*
  • Nominal Testing Pressure: 15.5 bar (225 psi / 1.55 MPa)*
  • Standard Test Conditions: 2,000 ppm NaCl solution, 25 deg C, pH 7.5, 8% recovery*
  • Maximum Working Pressure: 41.4 bar (600 psi / 4.14 MPa)
  • Maximum Feed Water Flow Rate: 3.6 m3/h (16 gpm)
  • Maximum Element Pressure Drop: 0.1 MPa (1.0 bar / 15 psi)
  • Maximum Feed Water Temperature: 45 deg C
  • Continuous Operating pH Range: 2.0 to 11.0
  • Chemical Cleaning (CIP) pH Range: 1.0 to 13.0
  • Maximum Feed Water SDI15: < 5
  • Free Chlorine Tolerance: < 0.1 mg/L (ppm)
  • Total Overall Length (A): 533.4 mm (21.0 inches)
  • Element Outer Diameter (B): 99.7 mm (3.9 inches)
  • Permeate Core Tube OD (C): 19.1 mm (0.75 inches)
  • Permeate Extension Length (D): 26.7 mm (1.05 inches)
  • Net Weight: 3.0 kg
  • Primary Compatibility: Commercial and laboratory RO systems utilizing 4021 pressure vessels (including Aquaphor Professional, Ecosoft, and standard universal housings)

*Permeate flow rate for single elements has an allowable tolerance within +/-15% under standard test conditions.

  • Commercial drinking water purification, cafes, restaurants, and bakeries
  • Food processing and commercial beverage preparation
  • Boiler feed and steam generation water treatment
  • Semiconductor and microelectronics rinse loops
  • Pharmaceutical, cosmetic, and laboratory pure water production
  • Desalination of tap, well, and surface water supplies with TDS up to 2,000 ppm

Please note: Strict adherence to initial start-up procedures is required to protect the membrane from hydraulic shock and overfeeding. Flush the system at low pressure for 15 to 25 minutes, followed by high-pressure circulation for 60 to 90 minutes. All permeate and concentrate water produced during the first hour of operation must be discharged directly to the drain. Maintain the element continuously wet after its initial wetting, and ensure zero backpressure builds up on the permeate side. If shutting down the system for more than 72 hours, store the element in a 1.0% sodium bisulfite protective solution to prevent microbial growth.