MULTI-STAGE DESALINATION OF LOW ENTHALPY

摘要

A multi-stage system for low-enthalpy desalination which consists of serially connected evaporators (lv) consisting of condensers (cv) arranged on a single level at the top of a tower (40), their respective evaporation chambers (ev) being arranged at progressively lower levels and connected to the condensers (cv) via vertical air ducts (2v) of progressively increasing height. The system is based on the violent/flash boiling of seawater which has been heated to a temperature slightly lower than the boiling point, and introduced in an environment of lower pressure. Passive vacuum is employed, which is generated by applying atmospheric pressure and gravity. Pressure stepping-up (pv) is achieved by progressive increase in the volume of the evaporators. Air removal is achieved by the dynamic vacuum generated in ejectors (12, 13a, 13b) which employ the produced desalinated water and the discharged brine as auxiliary medium.