Osmotic transfer
Water moves into the draw; the feed concentrates.
Draw Solution Recovery · Low-Grade Heat
Thermal FO Draw
& regenerationTrevi's retrograde thermolytic draw, AquaDraw™, creates the osmotic driving force, separates with low-grade heat, and returns to the loop.
Membrane · Separation · Heat Recovery · Polishing
Draw Regeneration in the FO Loop
Transferred water dilutes Trevi's patented draw. Heat then separates a water-rich phase and restores concentrated draw.
Thermal conditioning
Recuperated and fresh low-grade heat warms the diluted draw.
Phase separation
The stream separates into water-rich and re-concentrated draw phases.
Polish
The water-rich phase moves through the finishing train.
- Draw role
- Create the osmotic driving force
- Intermediate
- Diluted draw · not finished water
- Thermal role
- Separate water-rich and draw-rich phases
- Complete duty
- Heat · pumping · rejection · polishing · draw management
Draw identity is proprietary; performance depends on the feed, heat source, and project design.
Review the Draw Design BasisThermal FO in the field · NELHA, Hawaii
Membrane, Heat, and Finishing in One Demonstration
- PublishedEvidence
- Site-specific solar-thermal FO demonstration U.S. Department of Energy
- DesignStated capacity
- 500 m³/day Trevi · Toyobo
- PublishedFeed
- Seawater at NELHA's Keahole Point facility
- PublishedThermal source
- Concentrating solar thermal (~2 MW array)
The report establishes recovery, thermal and electrical consumption, water quality, and opex/capex savings for this installation.
Feed assay · Heat profile · Product specification
Bring the feed, heat source, and water target. We'll define the test.