MEJORAS INTRODUCIDAS EN UN SISTEMA EVAPORADOR DE EFECTO MULTIPLE.

摘要

1433207 Multiple-effect evaporation AEROJET-GENERAL CORP 4 Oct 1973 [6 Oct 1972] 46466/73 Heading B1B Multiple-effect evaporation of a liquor such as brine is carried out in a cylindrical housing divided by barriers into effects each containing vertical bundles of heat transfer tubes whereby concentrate from the bundles is transferred to the evaporating side of the next adjacent effect to obtain a still further concentrate and the vapour is transferred to the condensing side of the next lower pressure effect to form a condensate characterised by the division of the flow of feed stream into two preheating internally disposed longitudinally-extending bundles of tubes located along opposite inside walls of the housing with preheater sections being divided into compartments each of which is associated with the condensing side of a single effect from which uncondensed vapour can be used to heat the corresponding section of the tubes in the compartment. A feed stream 11 is split and fed to the two bundles of tubes 42 and 44 which are split into preheater compartments 26 and 27 alternatively associated with the different effects 1-8. The preheated streams are reunited and fed to the vertical tubes of effect No. 1. Steam from line 14 passes into vapour chest 15 (1) and flows through the vapour space of the condensing side of the tube bundle. Steam condensate is removed via line 24 (1) to the associated preheater section 27 (1). The uncondensed vapour is passed by internal line 31 (1) to condense on that part of the tube bundle 44. in the associated section 27 (1) and passes to the condensate pool. The concentrate from the vertical tube bundle of effect No. 1 collects in a sump from whence the brine vapour passes via filter 20 (2) and enters the condensing side of effect 2 where it provides the heating medium for the vertical tube bundle of effect 2. The concentrate from the sump of effect 1 is passed via concentration chest 22 (2) to be heated in tube bundle 12 (2). The exhaust vapours from the condensing side of effect 2 pass via line 30 (2) to the associated preheater section 26 (2) while the condensate passes via line 24 (2) to the same section. This procedure is repeated in the following six effects until the concentrate to be discharged is removed from sump No. 8 in line 50. The condensate products of the preheater compartments are removed in lines 52 and 54 combined and introduced to a final condenser 56 and the product is removed at line 60.