GB901077A - Evaporator - Google Patents

Abstract

A flash evaporator for water distillation comprises an elongated, preferably cylindrical, shell 10 (Fig. 1) divided by a central, vertical, longitudinal wall 12 and a plurality of transverse partitions 11a ... 11n into a first series of flash chambers 13a ... 13n extending along one side of the shell and a second series of flash chambers 14a ... 14n extending along the other side of the shell. A condenser tube bundle 22 (Fig. 2) extends lineally through each series of chambers and condensate is withdrawn at 24. Each chamber is also provided with anti-splash channels 20 and a demister 21. Communication between adjacent chambers is established by an opening 17 in the base of each transverse partition, and water passes from chamber to chamber via a perforated plate 19 and weir 18 (Fig. 3) the latter being of greater depth than the opening 17 and thereby effecting a liquid seal between the chambers. Feed water is passed into and through the condenser tubes in chambers 14a ... 14n, then, via a conduit 26, through the condenser tubes in chambers 13n ... 13a, then through a heater 28 and pipe 29 into the base of the first flash chamber 13a and then sequentially through flash chambers 13b ... 13n and 14n ... 14a, unflashed water being finally discharged at 32. Th vertical wall 12 (Fig. 2) is preferably of hollow insulating construction, the gap 12c if desired being packed with insulating material. <PICT:0901077/III/1> <PICT:0901077/III/2> <PICT:0901077/III/3>