METHOD AND PLANT FOR CONCENTRATING AQUEOUS SALT SOLUTIONS Russian patent published in 1999 - IPC

FIELD: recovery of liquid radioactive wastes. SUBSTANCE: method involves heating of solution and evaporation of water from it under vacuum built up by speeding up water and condensed steam flow, steam concentration, and production of concentrated still bottoms. Steam is condensed by flow of water and condensed steam whose pressure is raised to atmospheric value; solution is heated by indirect heat transfer from hot water and condensed steam flow. Condensing plant has water solution evaporation chamber with liquid and steam spaces and sprayer in steam space, steam-liquid ejector, condensed steam collector, condensate and solution pump, and heat-transfer apparatus. In addition, it is provided with surge tank and pump used to force condensate through double-section heat-transfer apparatus; surge tank communicates through its inlet with outlet of liquid-steam ejector and through its outlet, with pump forcing condensate through double-section heat- transfer apparatus; the latter is mounted in liquid space of evaporation chamber. EFFECT: improved efficiency of method and reduced power requirement. 4 cl, 1 dwg