Patent GB-757085-A (GB)
Title: Improvements in or relating to compression stills and method of continuous distillation
IPC: B01D1/28
Filed: 1953-06-12
Abstract: <PICT:0757085/III/1> <PICT:0757085/III/2> <PICT:0757085/III/3> A still of the vapour-compression type comprises a hollow member, made of material of high thermal conductivity, mounted for rotation, means for supplying distilland to one surface (the inner or the outer) of the rotating member over which surface the liquid flows by centrifugal force as a very thin film and is subjected to partial evaporation, means for collecting undistilled residue from this evaporating surface, and means for compressing the vapours and for conducting the compressed vapours into contact with the reverse side of the rotating member; the compressed vapours condense on this reverse side and give up heat (via the wall of the member) to the film of distilland flowing over the evaporating surface.  In Fig. 5, a pair of cones 370 is mounted in a casing 367 on bearings 376 378. The cones are connected by a spider 402 to a shaft 404 which passes through bearing 376 to a suitable driving means (not shown).  A centrifugal compressor 372 and an electric motor 374 for driving it are supported on cover 368.  Distilland is supplied through pipe 380, valve 382, degasser 384, pipe 386 and nozzles 388 to the centre of the interior surfaces 390 of the cones 370 which are rotated at such a speed as to cause the distilland to flow on the surfaces as thin films.  The vapour evolved from the flowing films on surfaces 390 is withdrawn through conduit 392 by compressor 372.  The compressed vapour is discharged through conduit 394 into casing 367 where it contacts the outer surfaces of heat-exchange barrier 370, and is condensed thereon as a flowing film.  The condensate is withdrawn from the casing through pipe 393 and pump 394. Undistilled residue is collected in gutters 396 and removed therefrom by pipes 398 which pass out through bearing 376.  The degasser 384 and the casing 367 may be evacuated by suction pumps 400.  In Figs. 8 and 9, heat exchange barrier 504 is mounted for rotation on shaft 506 which is journalled on bearings in casing 508.  The barrier is provided with curved volutes 500, and is rotated by directing powerful jets of distilland, supplied to pipe 502 by a pump (not shown), against one of these volutes. Compressor 510 withdraws vapour from evaporating chamber 512 through conduit 514; and discharges the compressed vapour into the interior of the barrier 504 where it condenses on the inner surfaces thereof.  The condensate is collected in an annular trough formed in the end plate 518, and is withdrawn through pipe 516.  This embodiment is particularly adapted for the concentration of slurries and fruit juices, since any suspended matter in the feed is flung off the rotating barrier.  Also the construction is partly self-pumping as regards vapour and may be made entirely so (i.e. compressor 510 may be dispensed with) by driving the barrier at high speed with an external driving means. The distillation of brackish waters, sea water petroleum distillates, alcohols ethers and esters, is also referred to. Specification 163.793 [Class 32], is referred to.