US3010702A

US3010702A - Heat exchange for continuous throughflow of two media

Info

Publication number: US3010702A
Application number: US561017A
Authority: US
Inventors: Mautner Mihajlo; Geric Zvonimir
Original assignee: Separator AB
Current assignee: Alfa Laval Holdings Amsterdam AB
Priority date: 1955-02-16
Filing date: 1956-01-24
Publication date: 1961-11-28
Anticipated expiration: 1978-11-28
Also published as: FR1141319A; DE1064968B; GB797962A

Description

HEAT EXCHANGE FOR CONTINUOUS THROUGHFLOW OF TWO MEDIA Filed Jan. 24, 1956 Nov. 28, 1961 M. MAUTNER ETAL 2 Sheets-Sheet 1 9 L M a U w M 8 2 I O I Y A .15 1 m w E 8 6 ,A/M I4, I I Win95 m iiflllllll In \I BY AWM W ATTORNEYS Nov. 28, 1961 MAUTNER ETAL HEAT EXCHANGE FOR CONTINUOUS THROUGHFLOW OF TWO MEDIA Filed Jan. 24, 1956 2 Sheets-Sheet 2 Fig.3

United States Patent 3,010,702 HEAT EXCHANGE FOR CONTINUOUS THROUGH- FLOW OF TWO NIEDIA Mihailo Mautner, Milenko Flego, and Zvonimir Geric, Zagreb, Yugoslavia, assiguors to Aktiebolaget Separator, StoMolm, Sweden, a corporation of Sweden Filed Jan. 24, 1956, Ser. No. 561,017 Claims priority, application Yugoslavia Feb. 16, 1955 6 Claims. (Cl. 257-241) The present invention relates to a heat exchanger adapted for continuous throughflow of two media during the heat exchange operation and which comprises a hollow, single-walled rotor provided with an inlet and an outlet for one medium, and a closed housing surrounding the rotor and having an inlet and an outlet for the other medium.

In a heat exchanger made according to the invention, the hollow of the rotor is kept separate from the hollow of the surrounding housing by means of sealing devices; the inlet of the rotor opens into the hollow of the rotor at one end of the rotor; at paring device is arranged in the outlet of the rotor at the other end of the rotor; and the inlet and outlet of the rotor are so arranged that the first medium passes through the rotor from its inlet to its outlet in a relatively .thin layer spread over the surface of the rotor wall. The latter feature involves a certain dimensioning of the inlet and outlet and also location of the paring device at a suitable distance from the center of the rotor.

The apparatus of the invention can be used for various kinds of operations, such as evaporation with or without vacuum, vaporization, deodorization of vegetable oils, redistillation of aromaticrand etherial oils, vacuum distillation of all kinds (eg partial distillation, selective distillation, etc.), and cooling.

For a better understanding of the invention, reference may be had to the accompanying drawings, in which:

FIG. 1 is a vertical sectional view of a preferred form of the new apparatus;

FIGS. 2, 3 and 4, are vertical sectional views of modifled forms of the rotor body shown in FIG. 1', and

FIG. is a vertical sectional view of a modified form of the device for supplying one of the fluid media which are passed through the heat exchanger.

Referring to FIG. 1, the heat exchanger there shown comprises a hollow rotor 1 surrounded by a housing 2. The rotor i is provided at its ends with hollow pivots or trunnions 3 and 4 by means of which it is rotatably mounted in

ball bearings

5 and 6. The upper bearing 5 is fitted in a neck-like extension 7 of the surrounding housing 2, and the lower bearing 6 is fitted in a sleeve 8 in a frame 9 supporting this housing. The hollow of the rotor i is kept separate from the surrounding housing 2 by sealing means it The latter, as illustrated in FIG. 1, comprise elastic rings 19:: closely surrounding the upper trunnion 3 and secured to metal rings which fit closely in the neck 7 above and below the bearing 5.

The rotor is provided with a central stationary feed pipe 11 which extends through the upper trunnion 3 into the interior of the rotor and forms an inlet which opens into the lower end of the rotor. The rotor also contains a stationary paring device 12, the entrance or mouth of which is located in a widened part of the hollow of the rotor at its upper end, the rotor having substantially the form of a truncated cone. The paring device 12 forms an outlet connected with a stationary discharge pipe 13 extending through the lower trunnion 4, which passes through a central opening in the lower end portion 15 of the surrounding housing 2. The clearance between the lower trunnion 4 and the edge of this central opening isclosed by a sealing device 14. The housing 2 has at although the generatrix may take other forms.

3,010,702 Patented Nov. 28, 1961 "ice its upper part an inlet 16 and at its bottom an outlet 17. The hollow of the rotor may communicate with a suction device through the channel in the upper trunnion 3 and an outlet 18.

The rotor is driven by means of a on the lower trunnion 4. The space nel in this trunnion 4 and the discharge pipe by means of a sealing device 20. The rotor is at its upper end with one or more conveyor vanes which extend generally radially of the rotor axis.

When the heat exchanger is used for evaporation purposes, for example, the heat-emitting medium, which may consist of steam, is supplied through the inlet 16. The heat-absorbing medium is introduced through the pipe 11 into the lower part of the rotor 1 and is spread in a relatively thin layer over the conical wall of the rotor. Under the influence of the centrifugal force resulting from the rotation of the rotor, the heat-absorbing medium passes towards the upper part of the hollow of the rotor and is there pared out by the paring device 12. The heat-emitting medium may be condensed by contact with the outside of the rotor, and the resulting condensate is immediately thrown away from the rotor wall by the influence of the centrifugal force. This condensate is collected at the bottom of the housing 2 and is discharged through the outlet 17, which may be connected with a condensate pump (not shown) or consist of a steam trap. As a result of the rotation of the rotor, there is thus obtained a high heat transfer coefiicient between the heatemitting medium and the rotor wall, partly because of the velocity gradient in the heat-emitting medium and partly because, as previously mentioned, any condensate formed on the rotor wall is the rotor Wall. In a similar manner, a high heat-transfer coefficient is obtained on the inside of the rotor between the rotor wall and the heat-absorbing medium, since by adjusting the speed of rotation of the rotor and the throughflow rate, the velocity of this medium can be kept relatively high on the inside of the rotor wall, and any gases or vapors which may be present in the heat-absorbing medium and which are released, for instance, by evaporation, can be rapidly separated out or be removed through the influence of the centrifugal force. These gases or vapors are discharged through the channel in the trunnion 3 and the outlet 18, which form a suction line leading from the interior of the rotor 1. It is evident that by connecting the outlet 18 with a vacuum pump, or the like, it is possible to obtain a sub-atmospheric pressure in the hollow rotor, whereby the evaporation can take place at the temperature most suitable to each individual case.

The rotor 1 of the heat exchanger shown in FIG. 1 has substantially the form of a truncated cone, the lateral surface of which is formed by a rectilinear generatrix,

According to FIG. 2, the generatrix is bent so that the diameter of the rotor 1 increases slowly at the lower end 1a of the rotor, where the material which passes through the hollow of the rotor is introduced, but increases more rapidly at the opposite end 1b where the material is discharged. This can be of advantage in the treatment of certain kinds of material, since it enables control of the axial flow velocity of the medium so that this velocity is either changed or is kept constant in spite of the fact that the viscosity increases through the evaporation of the medium. In certain cases it is desirable that the diameter of the rotor vary as shown in FIG. 3, where the diameter at the two ends 1a and 1b of the rotor changes relatively slowly in the longitudinal direction of the rotor, while between the ends of the rotor there is a zone 1c where the diameter of the rotor changes more rapidly.

An enlargement of the heat-transmitting area can be pulley 19 arranged between the chan- 13 is closed provided 21,

immediately thrown out from dium, the rotor wall forming a surface rounding the rotor, in the form of jets directed straight toward the outside of the rotor or in jets which are more or less tangential to the rotor. The distributing tubes 22 may be connected to a common feed pipe 25 vided with a connecting flange 2'4.

. We claim: 1. In aheat exchanger adapted for continuous throughduring heat exchange operation, the

suitably pr-' through the 7 said pipes forming an inlet for theheat-absorbing medium 7 and opening-into the rotor at said small end thereof, a

paring device located in said large end of the rotor at the outer part thereof and forming an outlet from which the other pipe leads to discharge the heat-absorbing meover which the a screw or spiral. Such heat-absorbing medium passes in a thin layer through the rotor from said small inlet end to the large outlet end thereof, one of said trunnions forming with the corresponding pipe an annular passage leading from the rotor, and a suction line leading from said annular passage for evacuating gases emitted from said thin layer of the heatabsorbing medium.

2. The combination according to claim 1, in which said inlets and outlets of said space and the rotor are positioned for counter-current flow of said two media. a

3. The combination according to claim 1, in which the rotor wall is corrugated.

4. The combination according to claim 1, in which said space inlet for the heat-emitting medium includes nozzles opening into the housing adjacent the rotor and arranged to direct jets of said heat-emitting medium against the outside of the rotor.

5. The combination according to claim 1, in which said space inlet for the heat-emitting medium includes nozzles opening into the housing adjacent the rotor and arranged to direct'jets of said heat-emitting medium against the outside of the rotor, and distribution tubes to which the nozzles are connected. V

6. The combination according to claim 1, comprising also a seal between the other of said trunnions and the communication between the interior of the rotor and atmosphere through said trun- References Cited in the file of this patent ITED STATES PATENTS 570,737 Sharples Nov. 3, 825,721 Hartmann July 10, 1906 879,490 Rasmussen Feb. 18, 1908 1,004,760 Fetz'er Oct. 3, 1911 1,093,500 Todt Apr. 14, 1914 1,701,777 Jensen Feb. 12, 1929 1,930,479 Jones Oct. 17, 1933 2,067,273 Knowles et al. Jan. 12, 1937 2,119,907 Dunlap June 7, 1938 2,169,601 Cornelius et a1 Aug. 5, 1939 2,318,293 Cornell May 4, 1943 FOREIGN PATENTS 146,391 Australia Sept. 6, 1951