High-Efficiency Membrane Separation & Seawater Purification Systems
Explore our wholesale-ready industrial water production modules, tested under rigorous Factory Acceptance Testing (FAT) protocols prior to international export.
Two-Stage RO Purified Water System
Designed for food, beverage, and sterile processing with integrated deep disinfection technology and continuous automated sanitization cycles.
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Osmosis-Assisted RO Concentration
High-salinity brine volume minimizer using advanced OARO technology, reducing hydraulic pressure loads in extreme recovery conditions.
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DTRO & STRO Membrane Concentration
CE-certified disc-tube and spacer-tube reverse osmosis for handling high-fouling, heavy-particulate seawater concentrates and industrial leachate.
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Custom Environmental Treatment Skids
Wholesale OEM precision manufacturing for industrial EPCs, integrating custom alloy fabrication and automated control systems.
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High-Ratio Industrial Water Reuse
Factory-assembled multi-stage membrane reclamation equipment designed to treat complex industrial wastewater and marine return streams.
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Advanced Process Water Reclamation
Engineered for high flux stability, low chemical consumption, and extreme recovery rates in coastal chemical processing operations.
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High-Pressure DTRO/STRO System
Robust open-channel construction resisting particulate plugging; operates up to 120 bar for high recovery seawater & wastewater concentration.
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Modular Containerized SWRO Plant
Rapid-deployment mobile seawater desalination housed in standard ISO shipping containers for off-grid coastal, mining, and island facilities.
View SpecificationsThe Evolution of Seawater Treatment: From Thermal Evaporation to Next-Gen SWRO
Global baseline analysis on energy efficiency optimization, total dissolved solids (TDS) management, and modular skid engineering for high-capacity industrial procurement.
Specific Energy Reduction (SEC)
Modern seawater reverse osmosis (SWRO) facilities operate under 3.0 kWh/m³ by employing isobaric pressure exchangers (PX) that recover upwards of 96% of kinetic energy from concentrated brine reject streams.
Metallurgical Integrity
Preventing localized crevice and pitting corrosion requires high PREN (≥42) Super Duplex Stainless Steels (2507 / UNS S32750) and SMO 254 for high-pressure manifolding and high-salinity wetted parts.
Pretreatment Automation
Mitigating biological fouling and silt density index (SDI < 3.0) requires multi-media pressure filtration paired with pressurized Ultrafiltration (UF) hollow-fiber membranes running automated backwash sequences.
Modular Footprint Scalability
Containerized standard 20ft and 40ft high-cube layouts cut on-site civil commissioning lead times by 75%, allowing rapid plug-and-play tie-ins for remote resorts, offshore platforms, and coastal municipalities.
End-to-End Seawater Treatment Process Engineering Framework
A rigorous walk-through of the multi-barrier process train designed by Shanghai Tongjie to guarantee operational reliability in demanding ocean environments.
Intake & Physical Pretreatment
Raw seawater (32,000–45,000 ppm TDS) enters through screened open intakes or beach wells. Dual-media sand filtration and Dissolved Air Flotation (DAF) remove marine organics, red tide microalgae, and suspended solids.
- Automated coagulant & flocculant metering
- Sodium hypochlorite biofouling shock dosing
- 5-micron security cartridge microfiltration barrier
Pressurized Membrane Separation
High-pressure positive displacement or multi-stage centrifugal pumps boost feedwater to 55–82 bar (800–1200 psi). Thin-film composite (TFC) aromatic polyamide membranes systematically separate ions via cross-flow reverse osmosis.
- Isobaric ceramic rotor Energy Recovery Devices (ERD)
- Boron rejection optimization (< 0.5 mg/L via pH trim)
- Continuous normalized flow and salt passage logging
Remineralization & Safe Discharge
Permeate water undergoes calcium carbonate calcite contact bed dissolution and carbon dioxide equilibrium adjustment to stabilize Langelier Saturation Index (LSI) values before distribution into potable or industrial boilers.
- WHO-compliant post-chlorination / UV sterilizers
- Multi-port high-velocity brine dispersion outfalls
- Optional ZLD brine concentration coupling
Comparative Engineering Matrix for Seawater Desalination Projects
Procurement specifications and lifecycle capital optimization parameters across core industrial scenarios.
| Procurement Parameter | Municipal & Utility Scale | Offshore Oil, Gas & Marine | Industrial Complex & Boiler Feed | Tongjie Engineered Standard |
|---|---|---|---|---|
| Feedwater Salinity (TDS) | 35,000 – 42,000 mg/L | 38,000 – 45,000 mg/L | 32,000 – 38,000 mg/L | Customized up to 60,000 mg/L (High-TDS) |
| Pretreatment Scheme | Gravity DMF + Microfiltration | Compact Dual-Basket + UF Skids | Ultrafiltration (UF) + DAF | Integrated Ultrafiltration with Automated CIP |
| Wetted Materials Metallurgy | Super Duplex 2507 / FRP | Hastelloy C-276 / Super Duplex | Super Duplex 2507 / 316L SS | Super Duplex 2507 (High Pressure) / 316L (Low) |
| Specific Energy Consumption | 2.8 – 3.2 kWh/m³ | 3.5 – 4.2 kWh/m³ | 3.0 – 3.5 kWh/m³ | < 2.9 kWh/m³ (Isobaric PX Energy Recovery) |
| Product Water Quality | WHO Potable TDS < 400 mg/L | TDS < 150 mg/L; Cl⁻ < 50 mg/L | Demineralized / Boiler Grade | Two-Pass / RO+EDI: Conductivity < 0.1 µS/cm |
| Factory Testing & Commissioning | Civil installation on-site | Explosion-proof modular skid | Turnkey pre-tested skids | 100% Wet FAT Pre-tested in Shanghai Factory |
Integrated Ecosystem: From Marine Extraction to Zero Liquid Discharge
Combining heavy-duty seawater desalination with advanced brine mining, zero liquid discharge (ZLD), and oilfield produced water systems.
Turnkey Containerized Plants
Fully climate-controlled 20ft and 40ft containers engineered with internal acoustic insulation, motorized ventilation, chemical dosing suites, and clean-in-place (CIP) tanks for rapid field commissioning in remote locales.
Zero Liquid Discharge (ZLD) Link
Our disc tube reverse osmosis (DTRO) and mechanical vapor recompression (MVR) crystallization units concentrate reject brine to dry commercial-grade salts, completely preventing hypersaline coastal plume contamination.
Produced Water & Frac Flowback
Cross-engineered oilfield skids merge oil-water hydrocyclones, ceramic microfiltration, and DTRO elements to recover fracturing return water to ≤5 mg/L oil content, supporting unmanned operations in Central Asian desert oil basins.
Regulatory & Marine ESG Compliance
Full CE directive compliance, ASME Section VIII pressure vessel certification, and ISO 14001 environmental frameworks ensure Tongjie systems integrate smoothly into World Bank and IFC funded environmental infrastructure projects.
Frequently Asked Questions: Seawater Treatment Process & System Procurement
Authoritative technical responses covering water chemistry, membrane longevity, energy balancing, and factory delivery protocols.
What raw water parameters are mandatory for sizing a wholesale SWRO plant?
We require comprehensive laboratory water testing: Total Dissolved Solids (TDS), conductivity, pH, water temperature variations (minimum and maximum), Silt Density Index (SDI-15), turbidity, Silica (SiO2), Boron, Iron, Manganese, Total Organic Carbon (TOC), and free chlorine content. This guarantees precise membrane projection modeling and prevents premature mineral scaling or biological membrane degradation.
How does Tongjie minimize power consumption on high-salinity seawater systems?
We integrate isobaric Energy Recovery Devices (such as ceramic rotor pressure exchangers or dual-work exchanger energy recovery systems). These devices transfer the high hydraulic pressure (up to 70 bar) of the reject brine stream directly to incoming feedwater with up to 97% transfer efficiency, decreasing the required high-pressure pump motor size and lowering total energy usage to below 3.0 kWh per cubic meter.
What metallurgy is selected for high-pressure wetted seawater piping?
Because warm seawater with chloride concentrations above 19,000 mg/L causes rapid pitting in standard 304 or 316 stainless steels, Tongjie exclusively fabricates high-pressure manifolding and pump casings from Super Duplex Stainless Steel (2507 / UNS S32750 / 1.4410) with a Pitting Resistance Equivalent Number (PREN) ≥ 42, ensuring a design lifespan exceeding 15 to 20 years.
What are the commissioning steps for containerized seawater desalination units?
Our containerized SWRO units are delivered pre-piped, pre-wired, and pre-commissioned from our Shanghai manufacturing facility. Site readiness requires only setting the container on a level foundation slab, connecting seawater intake and product lines, routing the brine outfall, and connecting the electrical power supply. Typical on-site commissioning is completed within 3 to 7 business days.
How does Tongjie achieve low boron concentrations for drinking and irrigation?
Boron (naturally occurring at 4.5–5.5 mg/L in seawater) exists as uncharged boric acid at neutral pH, passing easily through standard RO membranes. We implement a multi-pass process with inter-stage sodium hydroxide (NaOH) dosing to elevate the pH to ~9.5 in the second pass. This ionizes boric acid into charged borate ions, achieving >95% boron rejection and meeting WHO standards (<0.5 mg/L).
What is the typical membrane lifespan and recommended CIP cycle?
With proper ultrafiltration or multi-media pretreatment maintaining SDI-15 < 3.0, high-quality seawater polyamide membranes reliably achieve an operating lifespan of 3 to 5 years. Routine automated Clean-in-Place (CIP) is scheduled every 3 to 6 months depending on bio-load, utilizing targeted acid washes for mineral scale and alkaline surfactant cleans for organic fouling.
High-Spec Industrial Purification & Produced Water Equipment
Complete product line for semiconductor rinse, petrochemical flowback reuse, degasification, and off-grid containerized installations.
Global Brand Eco-Friendly ODM Skids
Turnkey contract manufacturing for global water brands, delivering custom dimensions, native PLC code, and multi-language HMI interfaces.
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Oilfield Fracturing Flowback Skids
Heavy-duty mobile treatment units engineered to clarify produced water and high-viscosity fracturing return fluids for direct reinjection.
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Semiconductor Ultrapure Water System
Multi-stage RO and Continuous Electrodeionization (CEDI) systems producing 18.2 MΩ·cm resistivity water for microelectronics wafer cleaning.
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CE-Certified OARO Brine Concentrator
Osmosis-assisted reverse osmosis hardware delivering significant volume reduction in chemical, electroplating, and marine reject streams.
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Integrated Pretreatment, UF & RO Skid
Compact, skid-mounted industrial reuse platform optimizing flux rates and reducing fouling when reclaiming secondary municipal effluent.
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Deoxygenation Membrane Degasifier
Physical hollow-fiber degassing contactors eliminating dissolved O2 and CO2 without thermal stripping, protecting downstream boiler piping.
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Multi-Stage Wastewater Reclamation
Engineered for complex organic loads, pairing biological contact oxidation with cross-flow membrane barriers for continuous zero-waste reuse.
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Instant Off-Grid SWRO Container Plant
Autonomous seawater reverse osmosis plant configured for direct solar PV or diesel generator interconnection, serving island utilities and defense bases.
View SpecificationsRequest an Engineered Seawater Treatment Proposal
Submit your raw water chemistry profile, target permeate flow rate, and local site voltage. Shanghai Tongjie’s engineering team will return a certified mass balance, membrane projection, and complete equipment budget within 48 hours.