Seawater Desalination & Brackish Water Treatment
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Reverse osmosis and thermal desalination for municipalities, hotels, and industry. Capacity planning, membranes, energy recovery, and B2B supply.
Desalination turns seawater or brackish water into process- and potable-grade supply. WorldwideTradeX designs and supplies reverse osmosis (RO) and hybrid pretreatment systems for hotels, resorts, industrial plants, and municipal projects — from containerized units to multi-train skid plants.
When Desalination Makes Sense
- Coastal hotels and islands without reliable freshwater
- Industrial processes needing consistent TDS (boilers, food, pharma)
- Brackish groundwater with high salinity
- Emergency / temporary supply during drought or infrastructure failure
Process Overview
| Stage | Function |
|---|---|
| Intake | Open sea, beach wells, or brackish wells |
| Pretreatment | Media filters, UF, antiscalant, chlorination |
| RO train | High-pressure membranes (SWRO / BWRO) |
| Post-treatment | Remineralization, pH correction, disinfection |
| Storage & distribution | Break tanks, pumps, telemetry |
Key Technical Parameters
| Parameter | Seawater RO (typical) | Brackish RO (typical) |
|---|---|---|
| Feed TDS | 30,000–45,000 mg/L | 1,500–10,000 mg/L |
| Product TDS | 200–500 mg/L | 50–300 mg/L |
| Recovery | 35–50% | 60–85% |
| Energy | 2.5–4.5 kWh/m³ (with ERI) | 0.5–1.5 kWh/m³ |
| Membranes | 8" SWRO elements | 8" BWRO elements |
Energy recovery devices (ERD) such as pressure exchangers are standard on larger SWRO trains — they can cut specific energy by 30–40%. Send the feed water salinity, the daily capacity and the site conditions and we will quote an RO train with its pretreatment package: request a quote.
Capacity Guide (B2B)
| Use case | Typical capacity |
|---|---|
| Boutique hotel / villa cluster | 5–50 m³/day |
| Resort / golf course | 50–500 m³/day |
| Light industry | 100–2,000 m³/day |
| Municipal module | 2,000–50,000+ m³/day |
Supply Scope
- Skid-mounted RO plants (containerized options)
- Pretreatment packages (UF/multimedia)
- Spare membrane elements, pumps, ERDs
- Chemical dosing kits (antiscalant, bisulfite, caustic)
- O&M manuals and remote monitoring options
Docs: GA drawings, P&ID, electrical schematics, COA for chemicals, CE where applicable
Procurement Checklist
- Feed water analysis (TDS, SDI, iron, manganese, silica, temperature)
- Required product quality and daily volume
- Power availability and footprint
- Climate and corrosion class (C5 coastal)
- Local O&M capability
FAQ
What is the difference between SWRO and BWRO?
SWRO treats seawater (~35 g/L TDS) at high pressure; BWRO treats brackish water at lower pressure and energy.
How often do membranes need replacement?
Typically 5–7 years with good pretreatment and CIP discipline; sooner if fouling is severe.
Can you supply containerized units?
Yes — 20'/40' containerized RO plants for fast deployment and mobile projects.
Is training included?
Operator training and commissioning support can be included in the supply package.
How do I get a quotation?
Send feed water analysis, target capacity, and destination via RFQ — we size the plant and issue FBO/CIF options.
Energy Consumption — The Dominant Cost Line
Energy is 40-60% of produced-water cost in RO desalination, so efficiency drives project economics:
- SWRO specific energy: modern plants with energy-recovery devices (ERI/pressure exchanger) run roughly 3-4 kWh/m3; older setups without recovery can exceed 6-8 kWh/m3.
- BWRO: lower osmotic pressure means roughly 1-2.5 kWh/m3 depending on TDS and recovery.
- Design levers: higher-efficiency pumps with VFDs, larger-membrane-area elements (fewer vessels), optimized recovery staged against feed quality, and renewable hybrid supply for off-grid sites.
Pre-Treatment — Where Most Plants Fail
Membranes are damaged or fouled by what enters them, not by the RO step itself:
- Filtration: multimedia + cartridge (5-10 micron) protection ahead of high-pressure pumps
- Antiscalant dosing: computer-modelled (e.g. against sulfate/carbonate scaling limits) per feed analysis
- Biological control: chlorination/dechlorination or UV where biofouling risk exists — chlorine must be fully removed before membranes (polyamide is chlorine-sensitive)
- Feed monitoring: online turbidity, ORP, and conductivity with automatic shutdown limits
O&M and Spare Parts
- Membrane element replacement typically staged (not full-set) at 5-7 year intervals under good pretreatment discipline
- CIP (clean-in-place) every 3-6 months depending on fouling; chemicals and procedures are standard supply items
- Routine consumables: cartridge filters, antiscalant, dechlorinant, testing reagents — annual consumption is forecastable and usually contracted
- Operator training packages and remote monitoring options are available with supply; plants with local technicians plus remote support show the best uptime record