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4040 Brackish Water RO Membrane (ULP31-4040) | Low-Pressure, 99.5% Rejection
- Model: ULP31-4040 – Brackish Water 4040 RO Membrane
- Low-pressure, high rejection: designed for 4″ vessels with easy retrofit
- Typical rejection: up to ~99.5% (NaCl, 25 °C, 2,000 ppm, 15% recovery)
- Energy friendly: lower ΔP at design flux → reduced kWh/m³
- Quality assurance: each element wet-tested; traceable serial No.
Product Description
ULP31-4040 Brackish Water RO Membrane
The 4040 brackish water RO membrane (ULP31-4040) is a low-pressure, high-rejection element for groundwater, well water, and industrial reuse applications. It fits standard 4″ pressure vessels and helps reduce operating pressure while meeting product conductivity targets. Each element is individually tested and serialized for traceability.
Where it excels
- Energy savings: achieve design flux at lower pressure compared with conventional 4040 elements.
- Stable product quality: high salt rejection reduces polishing load downstream.
- Easy retrofit: standard 1/2″ permeate tube, common interconnectors, and 4″ vessel compatibility.
Commissioning & acceptance (best practice)
- Normalize permeate flow to temperature; compare with clean baseline values.
- Verify product conductivity / salt rejection meets design spec at the target recovery.
- Confirm stage ΔP is stable after air purge and full wet-out.
- Record pressure (feed/concentrate/permeate), flow, and conductivity as your new baseline.
Note: Typical values below are for engineering guidance only. Always confirm with the latest datasheet and your feedwater analysis.
Related guides: RO membrane replacement · Cleaning & CIP · Troubleshooting
Product Parameter
| Item | ULP31-4040 (typical) | Test / Notes |
|---|---|---|
| Permeate flow | ≈ 2,400 GPD (≈ 9.1 m³/d) | 2,000 ppm NaCl, 25 °C, 150 psi (1.03 MPa), 15% recovery |
| Salt rejection | up to ~99.5% (typ.) | Based on NaCl; field results depend on recovery and temperature |
| Membrane type | Thin-film composite (TFC) | Dechlorination required before TFC |
| Element size | 4.0″ × 40″ | Standard 4″ vessel; verify brine seal orientation |
| Permeate tube (ID) | ≈ 0.75″ | Standard interconnectors |
| Operating pressure | Typically 70–200 psi (0.5–1.4 MPa) | Operate within supplier window for the target flux |
| Max feed temperature | 45 °C (113 °F) | Correct to 25 °C for normalized data |
| Allowable pH (continuous) | 2–11 | Cleaning pH up to 1–12 (short-term) as per supplier |
| Free chlorine tolerance | 0 mg/L (TFC) | Dechlorinate upstream; monitor ORP |
| Recommended SDI | < 5 (SDI15) | Keep iron/manganese within limits; antiscalant as required |
Values are typical and not guaranteed; design and acceptance should follow the latest model datasheet and site water analysis.
Applicable Industry
- Electronics & component rinsing (BWRO)
- Bottling / beverage make-up water
- Laboratories and pilot plants
- Hotel, clinic, and commercial water supply
- Well water and groundwater polishing before DI/EDI
Advantage One
Advantage 1 — Low Pressure, High Rejection
ULP31-4040 achieves design flux at lower ΔP while delivering high NaCl rejection. Plants typically see reduced specific energy (kWh/m³) and steadier product conductivity, especially at moderate recovery.Advantage TWO
Advantage 2 — Easy Retrofit & Simple Maintenance
Standard 4″ vessel compatibility, common interconnectors, and a 0.75″ permeate tube make changeout straightforward. Baseline acceptance is quick: verify normalized flow, product conductivity, and stage ΔP after wet-out.Related Products
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FAQ
Q1: How long does the reverse osmosis system last?
The lifespan of a reverse osmosis system depends on water quality and maintenance. Typically, the membrane lasts 2–3 years, while the system itself can last over 10 years with proper care.
Q2: Can the system be customized based on different water conditions?
Yes, all our systems are fully customizable. We analyze your water report and application needs before providing tailored solutions.
Q3: What standards does STARK equipment comply with?
Our products comply with CE, ISO 9001, and can be designed to meet specific regional regulations or industry standards upon request.
Q4: What is the delivery time for STARK RO systems?
Standard systems are shipped within 7–15 days. For customized orders, lead time may extend to 20–25 days depending on complexity.
Q5: Do you provide technical support or installation guidance?
Yes. We provide full technical documentation, remote guidance via video, and can dispatch engineers internationally upon request.
Q6: What is included in your quotation?
Our quotation includes the full RO system, control panel, pumps, pre-treatment units, and all necessary fittings. Installation tools and spare parts can be included upon request.