Deyuan Marine Offers Full Range of Marine Fresh Water Generators – Both Evaporation Type and Reverse Osmosis Type Available

DEYUAN MARINE, a professional marine equipment supplier, offers a complete range of marine fresh water generators (FWGs) covering both mainstream technologies – Vacuum Evaporation Type (Distillation Method) and Reverse Osmosis (RO) Type – to meet diverse vessel requirements for efficient, cost-effective and environmentally friendly fresh water supply.

Comparison of Two Core Technologies

Feature	Evaporation Type	Reverse Osmosis Type (RO)
Working Principle	Uses waste heat from main engine jacket water to evaporate seawater under vacuum, then condenses vapour into fresh water	Uses high-pressure pump to force seawater through RO membrane; water molecules pass through while salts are rejected
Energy Source	Waste heat (no additional fuel required)	Electrical power (drives high-pressure pump)
Energy Efficiency	Very high – utilises otherwise wasted heat	Moderate – consumes electrical power
Fresh Water Quality	Very high (≤10 ppm salinity)	Good (≤500 ppm, depends on membrane)
Sensitivity to Seawater Conditions	Low – unaffected by salinity turbidity or algae blooms	High – requires pre-treatment for turbid or high-salinity water
Footprint / Weight	Larger and heavier	Compact and lightweight
Start-up Time	Slower (needs to establish vacuum and heat)	Fast
Maintenance	Moderate – periodic cleaning of heat exchanger and ejector	Higher – membrane replacement every 3–5 years, regular filter changes
Typical Capacity Range	1 – 50 T/Day	5 – 1000 T/Day
Ideal Application	Ocean-going vessels (bulk carriers, tankers, container ships) with waste heat available	Vessels with limited space (tugboats, workboats, fishing vessels) or no waste heat source
Advantages	Low operating cost; insensitive to feed water quality; excellent water quality; uses waste heat	Small footprint; lightweight; quick start-up; no heat source required
Disadvantages	Larger installation space; requires stable waste heat source; slower start-up	Higher operating cost (electricity); membrane replacement cost; requires clean feed water
Classification Approvals	CCS, BV, DNV, ABS, etc.	CCS, BV, DNV, ABS, etc.
Automation	PLC control with salinity monitoring, auto blow-down	PLC control with salinity monitoring, auto flush

Selection Guidance

Deyuan Marine provides one-on-one technical advice to help owners choose the most suitable FWG type:

●Vacuum Evaporation Type – Recommended for ocean-going vessels with main engine or generator waste heat, especially for long voyages. Offers the lowest operating cost and highest water quality.

●Reverse Osmosis Type – Recommended for space-limited vessels or those without waste heat, where quick start-up and flexible installation are priorities.

Common Features & Certifications

Both technologies share the same high standards:

●Fully Automatic Control: PLC + touch screen with real-time salinity, temperature and pressure monitoring – automatic alarm or blow-down if limits are exceeded.

●Corrosion-Resistant Materials: Key components made of titanium alloy, duplex stainless steel or corrosion-resistant housings for long service life.

●Global Approvals: Available with class certificates from CCS, BV, DNV, ABS and other major societies.

“Fresh water supply is critical for ocean operations. Relying solely on port water is costly and constrained by port resources. Deyuan Marine offers two proven technology options, giving owners the flexibility to choose the best fit for their specific needs – achieving water self-sufficiency while cutting costs and emissions.” – Technical Manager, Deyuan Marine

Global Service Network

Deyuan Marine also provides a perfect after-sales service, including spare parts supply, remote technical support, ensuring reliable performance throughout the equipment's lifecycle.