The invention relates to a
seawater desalination method and device of natural vacuum and low temperature
distillation, which is characterized in that the
system must be airtight before operation, the water injection valve on the
system top is switched on to fill up the
system with
seawater; the drain valves of all drainage pipes connected with the
evaporation chamber are switched on, then the
seawater is flowed out under the influence of the gravity; the air in the system is discharged to make the system vacuum; the heat source can be conveyed to the
evaporation chamber now; when the temperature of heat source is higher than the
condensation temperature, the
evaporation pressure of the heated seawater is higher than the
condensation temperature of
fresh water, the evaporated vapor is condensed by the condenser under the action of
pressure difference between the evaporation pressure and the condensing pressure and finally the desalinated water can be obtained. The invention has the advantages that a sleeve regenerator is arranged on the connection section of the
water supply pipe of seawater and the
evaporation chamber, the heat of the strong brine discharged by the
evaporator is partially adopted to preheat the seawater in the
evaporator, the liquid in the system can flow freely due to the
pressure difference, thus the method can economize
energy source and the device can be used to desalinate the seawater on any sea island, water-deficient area or
brackish water area.