Patent ID: 6966974

Claim:
A method of evaporating a solution, comprising feeding the solution to heat transmission surfaces ( 4 ) of parallel plate-formed heat exchanger elements ( 3 ) of an evaporator ( 1 ), from supply units ( 6 , 31 ) spreading the solution to the top of said surfaces to flow downwards, removing the part of the solution ( 10 ) remaining from the evaporation and precipitate formed in connection with the evaporation from the lower end of the evaporator, and recycling said remaining part of the solution ( 10 ) back to the heat transmission surfaces ( 4 ) for re-evaporation, said recycling comprising conducting the solution to a liquid distribution space ( 14 ) common to said heat exchanger elements ( 3 ), separating the precipitate ( 23 ) from the solution in said distribution space, the solution forming an upward flow in the distribution space, and passing the solution to said supply units ( 6 , 31 ) for being spread onto the heat transmission surfaces ( 4 ), wherein the recycled solution is fed to the liquid distribution space ( 14 ) from a downwardly curved conduit ( 11 ) as a curved flow, to separate the precipitate ( 23 ) under the combined effect of gravity and centrifugal force, and the precipitate as separated is discharged to an exhaust pipe ( 21 ) from the bottom of the liquid distribution space.