SW30XHR-400/34i Extra High Rejection RO Membrane For Cold High Salinity Seawater

SW30XHR-400/34i Extra High Rejection RO Membrane For Cold High Salinity Seawater

SW30XHR-400/34i extra high rejection seawater RO membrane belongs to premium SW30XHR series, perfectly matched with SW30HR-380 standard seawater elements and PROC10 security pretreatment filters, delivering industry-leading 99.82% stabilized salt rejection and outstanding low-temperature separation stability for high-salinity cold seawater working conditions. Equipped with 400 sq ft oversized active membrane area and patented iLEC interlocking end cap structure, this polyamide TFC membrane achieves single-pass ultra-pure permeate without secondary boron removal equipment, adapts to raw water temperature down to 10℃ and salinity up to 40,000ppm. It features wide pH cleaning tolerance 1–13, slow concentration polarization fouling rate, effectively resolves two core pain points of conventional seawater membranes: severe rejection drop under low seawater temperature and insufficient purification effect for super high-salinity offshore brine, becoming the preferred upgrade model for high-standard desalination system integrators in cold coastal zones and polar marine platforms.

Product Description

Global industrial water procurement buyers constantly search long-tail keywords such as extra high rejection cold seawater RO element, single pass high boron removal SWRO membrane, iLEC interlocking 8-inch seawater membrane to replace medium-performance SW30HR-380 seawater membranes and low-rejection general-purpose SW series elements when designing cold-region desalination stations and high-salinity brine recovery lines. SW30XHR-400/34i is the flagship model of the SW30XHR ultra-high rejection series, specially customized to compensate the performance defects of common seawater membranes under low temperature and over-high TDS raw water, filling the market blank of high-efficiency seawater elements for frigid coastal, polar marine and deep offshore water-making projects.

Different from conventional seawater RO membranes whose salt rejection will decline sharply below 18℃ seawater temperature, SW30XHR-400/34i optimizes the surface charge density of polyamide separation layer through proprietary modification formula, maintaining stable 99.7% minimum guaranteed salt rejection even when raw water temperature drops to 10℃, eliminating the need for seawater heating equipment in cold-region desalination plants and cutting auxiliary heating energy consumption. Its 400 sq ft (37㎡) oversized active membrane area brings rated 6,000GPD permeate output under standard test conditions, matching high-volume continuous water demand of large-scale industrial desalination projects.

The built-in iLEC interlocking end cap design is the core mark of this "i" suffix model, which replaces traditional adhesive end caps, effectively eradicates O-ring leakage risk caused by long-term high-pressure vibration, stabilizes permeate water quality for long-term operation. The product is fully compatible with standard 8-inch × 40-inch pressure vessels, can form multi-stage ISD internally staged desalination systems together with conventional SWRO elements, and perfectly matches the pretreatment process composed of PROC10 large-flow security filters and automatic antiscalant dosing devices, without redesigning pipeline layout for old desalination equipment renovation projects.

Targeted at end users including cold coastal municipal water plants, polar offshore drilling platforms, high-salinity underground brine mining factories and northern island residential water supply stations, this element addresses three tough procurement challenges in low-temperature high-salinity water treatment: extra heating cost for cold seawater, secondary purification investment due to insufficient single-pass water quality, frequent maintenance caused by end cap leakage and unstable pressure difference.

Working Principle

The core separation mechanism of SW30XHR-400/34i ultra-high rejection seawater RO membrane still adopts polyamide thin-film composite solution-diffusion principle, but its surface modified selective layer reconstructs molecular channel structure to adapt the low molecular activity environment of cold high-salinity seawater. Unlike common seawater membranes with wide molecular channels that cannot intercept tiny borate ions under low temperature, the SW30XHR series optimized compact separation layer forms uniform nano-scale permeation channels, ensuring water molecules pass through while locking almost all dissolved salt ions, boric acid compounds and heavy metal micro-particles at raw water side under low-temperature low-mobility conditions.

High-salinity cold seawater enters the element feed channel along 28mil thick wide corrugated spacer under high-pressure booster pump push. The cross-flow turbulence structure of the spacer enhances fluid scouring force at low water temperature, reduces ion deposition and scaling risk caused by slow molecular movement in cold water. Under 800psi standard operating pressure, water molecules diffuse through the dense polyamide selective layer into central permeate collection tube to form low-TDS, low-boron fresh water; high-concentration salt, boron and scaling substances are intercepted and discharged with concentrated brine.

The multi-short-leaf membrane sheet layout of SW30XHR-400/34i evenly distributes hydraulic pressure across the entire membrane surface, avoids local over-flux pollution accumulation easily triggered by low-temperature water flow. Even when raw water temperature drops to 10℃ and salinity rises to 40,000ppm, the uniform water flow distribution suppresses concentration polarization magnification effect, keeping salt rejection and boron interception rate stable without obvious attenuation. The whole physical separation process requires no heating or chemical additives, and the membrane layer will not produce irreversible separation efficiency loss under long-term cyclic cold and hot alternating working conditions.

Technical Features

1. Industry-leading extra high salt & boron rejection modification layer

Belong to SW30XHR ultra-high rejection series, stabilized sodium chloride rejection reaches 99.82%, minimum guaranteed salt rejection 99.7% and stabilized boron rejection up to 93%. The exclusive surface charge adjustment technology strengthens interception capacity of micro borate ions, single-pass permeate can directly meet WHO drinking water boron limit without secondary resin treatment, greatly simplifying post-treatment flow of high-standard desalination projects.

2. Special low-temperature stable separation formula for cold seawater

Optimized polyamide molecular channel density targeting cold coastal and polar seawater; when raw water temperature ranges from 10℃ to 25℃, salt rejection fluctuation is controlled within ±0.1%, while conventional seawater membranes will drop over 0.5% rejection under the same low-temperature environment. It eliminates the need for seawater heating heat exchanger, reduces initial equipment investment and continuous heating power consumption for cold-region desalination stations.

3. Patented iLEC interlocking end cap anti-leakage structure

Unique "i" suffix exclusive interlocking end cap, cancel traditional glue bonding process, mechanical snap assembly forms fully sealed water flow channel. Under long-term 1200psi high pressure and ship vibration offshore working conditions, no O-ring displacement or raw water leakage occurs, avoiding permeate water quality deterioration caused by mixed raw water and produced water, cutting regular gasket replacement maintenance frequency.

4. 400 sq ft oversized active membrane area matched high-salinity high-flow demand

400 square feet (37㎡) effective filtration area, single element rated permeate flow 6,000GPD under standard test conditions. For high-salinity raw water with 35,000–40,000ppm TDS, the large membrane area disperses single-point flux load, slows scaling ion concentration accumulation speed, extends the cycle of CIP chemical cleaning compared with 340sq ft small-area seawater elements.

5. Ultra-wide acid-base cleaning window adaptable to complex on-site cleaning agents

Continuous stable operation pH range 2–11; short-term 30-minute chemical cleaning supports pH 1–13 strong acid and strong alkali environment. Compatible with industrial citric acid, sodium hydroxide, organic scale removers and biological cleaning agents commonly used in cold-region desalination plants, no special neutral cleaning chemicals required, flexible matching existing on-site cleaning system formulas.

Product Advantages

1. Zero heating auxiliary cost for cold seawater treatment

The low-temperature stable separation performance is the core competitive advantage over conventional SW30HR seawater membranes. Projects located in northern cold coastal zones, polar offshore platforms and high-latitude islands can remove seawater heating equipment from the system design, cutting early equipment procurement cost and long-term electric heating operating expense, greatly lowering the overall lifecycle water production cost per ton of fresh water.

2. Single-pass water quality meets ultra-strict potable water standards without secondary polishing

99.82% extra high salt rejection and 93% boron interception realize one-step purification of cold high-salinity seawater. Municipal water supply, polar crew living water and high-standard aquaculture projects can cancel secondary boron removal resin tanks and ion exchange polishing equipment, simplify system layout, reduce equipment occupied area and later-stage resin regeneration chemical consumption.

3. iLEC interlocking end cap cuts long-term leakage maintenance loss

Mechanical interlock end cap eliminates glue aging leakage hidden danger existing in ordinary non-i series seawater membranes. Offshore mobile desalination ships and floating platforms with frequent vibration can reduce quarterly gasket inspection and replacement work, avoid system shutdown loss caused by sudden raw water leakage, lower post-operation labor and spare parts cost for system integrators.

4. Stable performance under super high-salinity raw water without rapid fouling

Aiming at 30,000–40,000ppm ultra-high TDS cold seawater and underground brine, the optimized membrane surface anti-scaling structure suppresses concentration polarization amplification effect under low temperature. Compared with standard SWRO elements, the differential pressure rising speed is reduced by over 30%, effectively prolonging the overall service life of membrane elements under high-salinity cold water working conditions.

5. Perfect compatibility with multi-stage ISD segmented desalination systems

400 sq ft large membrane area and consistent 8-inch universal dimension can be flexibly combined with medium-rejection SW30HR-380 seawater elements to build internal staged desalination systems. The ultra-high rejection permeate of SW30XHR-400/34i can directly serve as the feed water of secondary RO stage, improving overall system fresh water recovery rate without additional pretreatment transformation.

Application Fields

1. Cold northern coastal municipal large-scale seawater desalination plants

High-latitude coastal cities in Northern Europe, North America and Northeast Asia face perennial low seawater temperature and seasonal salinity fluctuation. SW30XHR-400/34i extra high rejection seawater RO membrane maintains stable purification efficiency in winter cold seawater, single-pass water quality meets local strict drinking water codes, widely used in urban tap water expansion and emergency water resource reserve projects in cold coastal areas.

2. Polar & high-latitude offshore oil and gas drilling platforms

Arctic and subarctic marine drilling platforms operate in seawater temperature below 12℃ all year round, with raw water salinity up to 38,000–40,000ppm. The iLEC anti-leakage structure adapts long-term ship vibration environment, low-temperature stable performance cancels heating equipment, compact layout fits limited platform space, supplies qualified drinking water and industrial process water for offshore crew and production equipment.

3. High-salinity underground brine mining & zero liquid discharge projects

Inland salt lake brine, underground high-salinity mineral brine raw water has stable ultra-high TDS, and mining areas mostly belong to cold temperate zones with low annual average temperature. SW30XHR-400/34i ultra-high salt rejection recycles large volume of reusable fresh water from brine, reduces brine discharge volume, matches mineral enterprise ZLD wastewater treatment transformation, cuts industrial brine disposal and fresh water procurement cost.

4. High-latitude remote island resident & tourism resort water supply

High-latitude remote islands lack fresh water resources, underground brackish seawater temperature stays below 15℃ all year with unstable salinity. The oversized membrane area reduces the number of membrane racks for small and medium island desalination stations, dry storage compatibility supports long-term island centralized stocking, single-pass high-purity permeate meets tourist and resident daily domestic water demand without secondary purification equipment.

5. Cold-region industrial high-purity process water preparation

Cold climate chemical, lithium mining and power plant production lines require low-boron, low-TDS high-purity process water. Cold raw water leads to rejection attenuation of ordinary seawater membranes, while SW30XHR-400/34i maintains stable separation index under low temperature, ensures consistent process water quality, avoids production line fluctuation caused by unqualified water quality, and reduces enterprise product reject rate.

FAQs

Q1: What core advantage does SW30XHR-400/34i have over standard SW30HR series membranes under cold seawater below 18℃?

A1: SW30XHR-400/34i belongs to extra high rejection SW30XHR series with special low-temperature modified separation layer. When raw water temperature drops to 10℃, its salt rejection only fluctuates within ±0.1%, while common SW30HR models will have over 0.5% rejection drop. It can directly remove seawater heating heat exchangers from system design, saving long-term heating power cost for cold-region desalination projects.

Q2: What is the maximum feed water salinity that SW30XHR-400/34i can operate stably for long term?

A2: The optimal long-term stable operation salinity range is 25,000ppm–40,000ppm, covering natural cold seawater, underground high-salinity brine and concentrated brine from primary RO systems. It can bear short-term instantaneous salinity up to 42,000ppm, but continuous operation above 40,000ppm will accelerate membrane surface scaling and shorten CIP cleaning cycle.

Q3: What is the function of iLEC interlocking end cap unique to SW30XHR-400/34i "i" suffix model?

A3: It cancels traditional glue bonding technology and adopts mechanical snap sealing structure. Under offshore vibration and long-term 1200psi high pressure, it avoids glue aging, O-ring displacement and raw water leakage problems of ordinary glued end cap membranes, prevents raw water-permeate mixing leading to water quality decline, and reduces quarterly gasket inspection and replacement maintenance workload.

Q4: Does SW30XHR-400/34i need secondary boron removal resin tank for municipal drinking water projects?

A4: No need. Its stabilized boron rejection reaches 93%, single-pass permeate boron content is lower than 0.5mg/L WHO drinking water limit under standard 32,000ppm seawater test conditions. Cold high-salinity municipal desalination projects can cancel secondary boron removal equipment, reducing system investment and occupied space.

Q5: Can SW30XHR-400/34i be matched with SW30HR-380 to build multi-stage ISD segmented desalination systems?

A5: Fully compatible. Both adopt standard 8-inch × 40-inch universal dimension, unified feed spacer thickness and pressure bearing parameters. SW30XHR-400/34i ultra-high rejection permeate can serve as secondary RO feed water, improving overall system fresh water recovery rate without modifying pretreatment pipeline matched with PROC10 filters.

Related Product Links

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SW30XHR-400/34i