Engineering · Auxiliary — Fresh Water Generator
A low-pressure (vacuum) fresh-water generator (evaporator) can boil seawater at about 40-60°C because:
- ASeawater has a low boiling point naturally
- BA vacuum lowers the boiling temperature, allowing waste heat from jacket water to drive evaporation✓ Correct
- CIt uses electric heaters only
- DThe seawater is pre-heated to 100°C
Explanation
Operating under vacuum lowers water's boiling point, so low-grade waste heat (hot jacket cooling water) can evaporate seawater. The vapor is then condensed to distillate, with a salinity cell dumping the product if salt content is too high.
Authority: Modern Marine Engineer's Manual; distillers
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