A distillation system is provided for recovering water from sea water and other polluted water source. The system has a heat engine embodying Carnot cycle and a Rankine cycle formed by heat exchangers, flash evaporator and condenser. Burnt gases from the engine such as a jet engine no longer fit for flying are directed into a duct where the exchangers are located. Sea water is pumped into the heat exchanger for preheating by residue heat in the duct and then into the exchanger for further heating. A recirculating pump raises water pressure in the exchanger for increasing boiling point to about 165 C. The heated water is fed into the evaporator where it changes into vapour and condensed into water by the condenser. The jet air stream is used to create Venturi effect for maintaining sub-atmospheric pressure in the evaporator. Any solid left in the evaporator is removed by a transfer mechanism.