A method for desalinating salt-containing water, especially water pit

The method of desalinating water of the invention consisting in that after chemical and mechanical pretreatment, saline water with a concentration of dissolved ions below 40 g/cu.dm is concentrated in a reverse osmosis installation 5 and then concentrated thermally, whereas saline water in which concentration of dissolved ions exceeds 40 g/cu.dm is concentrated directly thermally, is characterised by the fact that brine is concentrated in a single-stage evaporator 1, and during concentrating it is recycled in recirculation installation 6, while water vapour produced during brine concentrating is compressed in water vapour compressor 14 and returned to the single-stage evaporator 1 as a heating agent. Brine concentrated to more than 300 g/cu.dm of dissolved ions is directed via duct 13 to crystallizers 3 in which salts, mainly NaCl are precipitated.