ES321260A1 - Improvements in evaporators for the distillation of sea water - Google Patents

Abstract

Liquid, e.g. sea water, is distilled in a multiple effect evaporator comprising a series of metal plates 1 arranged face to face with spaces between them forming a series of cells 2, the whole series being disposed between a steam chest 23 and a condenser chamber 26. The cells are maintained under reduced pressure by pump 39. Sea water supplied through pipe 13, is distributed through pipes 11 and slots (not shown) so that it flows as a film down the right-hand side of each plate 1. The left-hand side of the first plate is heated by steam chest 23, and the vapour given off from the waterfilm on the other side of the plate flows across the cell 2 and condenses on the opposite plate and thus supplies heat through this second plate to the water-film flowing down its righthand side in the second cell. This same process of evaporation and condensation takes place in the following cells, but in the last cell the vapour condenses on the plate bounding the condenser chamber 26. The bottom of each cell is divided into two adjacent troughs by a vertical plate (not shown). Unevaporated water is withdrawn from the left-hand troughs through pipes 15 which lead to a common pipe 20. Distilled water is withdrawn from the righthand troughs through pipes 17 which lead to a common pipe 22. The unevaporated water and the distillate are withdrawn from the system via pipes 43 and 44, respectively, which pass through heat exchanger 38. The sea water to be distilled is pumped through heat exchanger 38, and is thereby preheated before it reaches to tops of plates 1. The distillation of ethyl alcohol, acetone and toluene is referred to. The recovery of butyl acetate from water is mentioned.