Frederick E Pitcher

US Patent:

42670225, May 12, 1981

Filed:

Apr 26, 1978

Appl. No.:

5/900079

Inventors:

Frederick L. Pitcher - Beverly MA

International Classification:

C02F 116
B01D 100

US Classification:

203 11

Abstract:

Method and apparatus for desalinizing water. Salt water in an evaporation zone is provided with heat of vaporization by a heat pump which transfers heat to the water from a thermal sink. The evaporation zone is maintained at subatmospheric pressure so that the salt water boils at a temperature at least about 10 degrees above the ambient dew point. The pressure in the evaporation zone is maintained at a low level by a vacuum pump and by condensing the vapor in a condensation zone from which fresh water is collected. The heat of condensation is dissipated into a "cold" sink if available or by a heat dissipating means such as an evaporative cooling apparatus. Energy efficiency results from the ability of the heat pump or pumps in the system to operate at a high coefficient of performance.