DEAERATING METHOD OF FLASH EVAPORATION TYPE SEA WATER DESALTING DEVICE

摘要

PURPOSE:To deaerate efficiently the dissolved oxygen in make-up sea water by providing a make-up sea water preheater in a make-up sea water line to a final stage evaporating chamber, and deaerating the make-up sea water in the evaporator after increasing the temp. thereof to the temp. in the evaporator or above. CONSTITUTION:A make-up water preheater 8 is provided before make-up sea water flows into a final stage evaporator, and the temp. of said water is increased by as much as the temp. at which flash evaporation is possible in the above-described final stage evapoator (for example, 1-2 deg.C) so that the rate- determining factor of deaeration is changed from the gas-liquid contact area and residence time to flash evaporation. The make-up sea water passing through a sea water line 6 is subjected to heat exchange with a heating fluid such as steam, hot water or the like in the preheater 8 by which the make-up sea water is heated to the temp. higher by 1-2 deg.C from the temp. in the final stage evaporator. The heated make-up water flows into the evaporator where the water is deaerated under flash evaporation and the temp. thereof is decreased to the brine temp. admitted therein from the previous stage.