Separating device for coiled heat exchangers for separating a gaseous phase from a liquid phase of a two-phase medium conveyed on the jacket side

Abstract

Helically coiled heat exchanger for the indirect exchange of heat between a two-phase first medium and a second medium has a shell surrounding a shell space, which extends along a longitudinal axis, an inlet for the admission of the two-phase first medium into the shell space, a tube bundle arranged in the shell space and having multiple helically coiled tubes for accommodating the second medium and a separating device for separating a gaseous phase from a liquid phase. The separating device has a tray arranged above the tube bundle which serves for collecting the liquid phase. The tray has a plurality of chimneys for separating the two phases. Each chimney projects from the tray from a side of the tray facing away from the tube bundle and is covered by a roof. An opening in the tray between the roof and an upper end of the respective chimney, there is provided an inlet opening via which the gaseous phase can flow into the respective chimney.

Claims

1. A helically coiled heat exchanger for the indirect exchange of heat between a two-phase first medium and a second medium, comprising: a shell which surrounds a shell space and which extends along a longitudinal axis, an inlet for admission of the two-phase first medium into the shell space, a tube bundle which is arranged in the shell space and which has multiple tubes for accommodating the second medium, which tubes are helically coiled about the longitudinal axis, and a separating device for separating a gaseous phase from a liquid phase of the two-phase first medium, wherein the separating device which is arranged above the tube bundle and which serves for collecting the liquid phase, wherein the tray has a plurality of chimneys for the purpose of separating the liquid phase and the gaseous phase, wherein each chimney projects from a side of the tray facing away from the tube bundle, is covered by a respective roof, and opens into a passage opening in the tray, wherein, between each respective roof and an upper end of the respective chimney, there is provided an inlet opening via which the gaseous phase can flow into the respective chimney.

2. The helically coiled heat exchanger as claimed in claim 1, wherein the tray has, in addition to the passage openings, a plurality of openings for uniform distribution of the liquid phase over the tube bundle.

3. The helically coiled heat exchanger as claimed in claim 1, further comprising a liquid distributor below the tray for distributing the liquid phase over the tube bundle, wherein the tray is in flow connection with the liquid distributor, situated therebelow, such that the liquid phase can pass from the tray into the liquid distributor.

4. The heat exchanger as claimed in claim 1, wherein the roof of each chimney has an encircling edge region with a bottom edge which runs at the height of or below an encircling end side of the chimney, which end side bounds the inlet opening of the chimney.

5. The heat exchanger as claimed in claim 1, wherein each of the chimneys extends along a respective axis which runs perpendicular to the tray.

6. The heat exchanger as claimed in claim 4, wherein the roof of each chimney projects, with the encircling edge region, beyond the chimney perpendicular to the axis of the chimney.

7. The heat exchanger as claimed in claim 1, wherein at least one chimney is formed as an outer chimney, wherein an inner chimney is arranged in the outer chimney, and the inner chimney extends upward through the roof of the outer chimney and extends, with an upper portion, beyond the roof of the outer chimney, wherein the upper portion of the inner chimney has an inlet opening which is in turn covered by a roof of the inner chimney such that the liquid phase can flow off the roof of the inner chimney past the inlet opening of the inner chimney onto the roof of the outer chimney and, from there, onto the tray, and such that the gaseous phase is additionally able to be conducted via the inlet opening of the inner chimney, situated below the roof of the inner chimney, into the inner chimney and, from there, to the tube bundle.

8. The heat exchanger as claimed in claim 7, wherein the roof of the inner chimney has an encircling edge region with a bottom edge which runs at the height of or below an encircling end side of the upper portion of the inner chimney, which end side bounds the inlet opening of the inner chimney.

9. The heat exchanger as claimed in claim 7, wherein the outer chimney extends along a respective axis which runs perpendicular to the tray, and the inner chimney extends along the axis of the outer chimney.

10. The heat exchanger as claimed in claim 8, wherein the inner chimney extends along a respective axis which runs perpendicular to the tray, and the roof of the inner chimney projects, with the encircling edge region, beyond the inner chimney perpendicular to the axis of the inner chimney.

11. The heat exchanger as claimed in claim 7, wherein the inner chimney is arranged coaxially with respect to the outer chimney.

12. The heat exchanger as claimed in claim 5, wherein the chimneys form a group of first chimneys and a group of second chimneys, wherein the second chimneys have, along their respective axis, a larger height above the tray than the first chimneys.

13. The heat exchanger as claimed in claim 12, wherein a spacing of a second chimney to the roof of an adjacent first chimney perpendicular to the axis of the second chimney is smaller than a protrusion of the roof of the adjacent first chimney beyond said first chimney perpendicular to the axis of said first chimney.

14. The heat exchanger as claimed in claim 12, wherein the first and second chimneys are arranged alternately along the tray.

15. A method for separating a gaseous phase from a liquid phase of a two-phase first medium and for exchanging heat between the first medium and a second medium using the helically coiled heat exchanger as claimed in claim 1, said method comprising: feeding the first medium, having the liquid and the gaseous phases into the shell space via the inlet, wherein the liquid phase, when impinging on a roof during the feeding, flows off past the inlet opening of the respective chimney onto the tray, and wherein the liquid phase is collected on the tray and subsequently distributed over the tube bundle and the gaseous phase is introduced via the inlet opening of the respective chimney, situated below the respective roof, into the respective chimney and, from there, is conducted via the associated passage opening through the tray to the tube bundle.

16. The heat exchanger as claimed in claim 12, wherein the first and second chimneys are arranged alternately along the tray such that a second chimney is in, each case, arranged between two adjacent first chimneys.

17. The heat exchanger as claimed in claim 12, wherein the first and second chimneys are arranged alternately along the tray such that a first chimney is arranged, in each case, between two adjacent second chimneys.

18. The helically coiled heat exchanger as claimed in claim 1, further comprising a core tube wherein the tubes of the tube bundle are coiled around or onto a core tube, and wherein the core tube extends in the shell space along the longitudinal axis of the shell.

19. The helically coiled heat exchanger as claimed in claim 18, further comprising a liquid distributor below the tray for distributing the liquid phase over the tube bundle below the tray, wherein the tray is in flow connection with the liquid distributor which is situated below the tray such that the liquid phase can pass from the tray into the liquid distributor.

20. The helically coiled heat exchanger as claimed in claim 19, wherein the flow connection between the tray and the liquid distributor includes the tray being connected to the core tube, such that the liquid phase which has been collected on the tray can pass into the core tube, and the liquid distributor having a plurality of arms in flow connection with the core tube which are designed to distribute the liquid phase over the tube bundle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the invention will be discussed by way of the following figure description of an exemplary embodiment on the basis of the figures.

(2) In the figures:

(3) FIG. 1 shows a schematic illustration of the separation of a liquid phase from a gaseous phase of a two-phase medium to be distributed over a tube bundle;

(4) FIG. 2 shows a schematic sectional illustration of an embodiment of a helically coiled heat exchanger according to the invention;

(5) FIG. 3 shows a schematic sectional illustration of a further embodiment of a helically coiled heat exchanger according to the invention;

(6) FIG. 4 shows a schematic sectional illustration of a further embodiment of a helically coiled heat exchanger according to the invention; and

(7) FIG. 5 shows, by way of example, a liquid distributor which may be used for distributing the liquid phase separated by a separating device according to the invention.

(8) FIG. 1 illustrates, in a schematic sectional view, the basic task of the distribution of a two-phase first medium M in a helically coiled heat exchanger 1. For this purpose, use is made according to the invention of a separating device 2 which separates a gaseous phase G from a liquid phase F of the first medium M. Thereafter, it is consequently possible for the liquid phase F and the gaseous phase G to be applied to the tube bundle 3 of the helically coiled heat exchanger 1 in each case separately and so as to be evenly distributed, which tube bundle is arranged beneath the separating device 2 and in which tube bundle a second medium M′ is conducted, with the result that the two media M, M′ are able to exchange heat indirectly. As already set out above, multiple medium may also be conducted separately on the tube side, which are then able to exchange heat indirectly with the first medium M.

(9) In the embodiments as per FIGS. 2 to 4, the helically coiled heat exchanger 1 has in each case a shell 5, which is preferably at least portionally cylindrical and which surrounds a shell space 6 of the heat exchanger 1, and a tube bundle 3, which is arranged in the shell space 6 and which may have multiple tubes 30 which may be helically coiled onto a core tube 300, wherein the core tube 300 is arranged in particular coaxially with respect to a longitudinal axis z of the heat exchanger 1 or of the shell 5, along which longitudinal axis the shell 5 extends. Said longitudinal axis z preferably runs parallel to the vertical. Furthermore, the helically coiled heat exchanger 1 as per FIGS. 2 to 4 has in each case an inlet 7 for the admission of the two-phase first medium M into the shell space 6 above a tray 4 of a separating device 2 which is configured for separating the gaseous and the liquid phases G, F of the first medium M such that the two phases F, G are able to be distributed over the tube bundle 3 separately. Here, the tray 4 runs horizontally or perpendicular to the longitudinal axis z and is arranged above the tube bundle 3, wherein said tray preferably extends over the entire cross-sectional area of the shell space 6 perpendicular to the longitudinal axis z and in this case subdivides the shell space 6 into two portions.

(10) In all the embodiments as per FIGS. 2 to 4, the tray 4 preferably serves for collecting the liquid phase F and is preferably flow-connected to a liquid distributor 4a via a suitable flow connection S, wherein the liquid distributor 4a is configured to distribute the liquid phase F over the tube bundle 3, wherein the liquid phase F acts on the tube bundle for example from above.

(11) As liquid distributor 4a, use may be made of the devices already described above. Of the various possibilities, FIG. 5 shows, by way of example, an embodiment of a liquid distributor 4a which may be used with all the embodiments of the separating device 2 according to the invention (for example according to FIGS. 2 to 4). As per FIG. 5, the tray 4 of the separating device 2 is connected to the core tube 300 of the heat exchanger 1 by means of a suitable flow connection S such that liquid phase F which has been collected on the tray 4 can pass into the core tube 300. The chimneys 50, 60, 70 of the respective embodiment (as shown in FIGS. 2 to 4, see below) are provided on the tray 4 as per FIG. 5, wherein the chimneys are not shown here for the sake of clarity. The liquid distributor 4a as per FIG. 5 then has, below the tray 4a of the separating device 2 and above the tube bundle 3, a plurality of arms 4b which are in flow connection with the core tube 300 and are designed to distribute the liquid phase F over the tube bundle 3 which is arranged below the arms 4b. Proceeding from the core tube 300, the arms 4b extend in particular in each case radially outward to the shell 5, wherein, between adjacent arms 4b, there are provided gaps through which the tubes 30 of the tube bundle 3, gathered in so-called clusters 31, are led upward past the arms 4b, wherein they open for example below the tray 4 into connecting pieces 32 provided laterally on the shell 5.

(12) As an alternative to a separate liquid distributor 4a (for example in the manner of FIG. 5 or as indicated in FIGS. 2 to 4), it is also possible in all the embodiments for the separating device 2 itself to function as a liquid distributor. For this purpose, the tray 4 may have a multiplicity of openings 40a which are distributed in particular uniformly over the tray 4 and via which the liquid phase F is then in each case applied to the tube bundle 3. A separate liquid distributor 4a may then be omitted.

(13) As per the exemplary embodiment of the present invention shown in FIG. 2, the tray 4 has, for the purpose of separating the two phases F, G of the first medium M, a plurality of passage openings 40 through which the gaseous phase G is distributable over the tube bundle 3. For this purpose, the passage openings 40 are in flow connection with in each case one associated chimney 50, wherein the respective chimney 50 is preferably formed by an encircling cylindrical wall 50, which is preferably a closed wall having no apertures and projecting from an encircling edge region of the respective passage opening 40 upward in the direction of an axis L of the respective chimney 50, from a side of the tray 4 facing away from the tube bundle 3, such that the respective passage opening 40 forms a downward directed outlet opening 40, facing the tube bundle 3, of the respective chimney 50. The axes L of the chimneys 50 are preferably cylinder axes L which run parallel to the longitudinal axis z of the heat exchanger 1 or of the shell 5.

(14) The respective chimney 50 furthermore has, at an upper end, an inlet opening 51 which is opposite the respective outlet opening 40 in the direction of the respective axis L and which, at the same time, is in each case covered by a roof 52 such that an encircling gap is formed between the respective roof 52 and the chimney 50 arranged therebelow. The liquid phase F, which is applied to the tray 4 or the separating device 2 from above, can then flow off the respective roof 52 past the respective inlet opening 51 or respective encircling gap onto the tray 4, where it is collected in order then to be distributed over the tube bundle 3 separately from the gaseous phase G, for example by means of the liquid distributor 4a which, more specifically, may be formed for example as per FIG. 5, while the gaseous phase G enter the associated chimney 50 via the respective gap, or the inlet opening 51 situated below the respective roof 52, and, from there, is able to be conducted via the associated passage opening or outlet opening 40 through the tray 4 to the tube bundle 3. As set out already, it is also possible to omit a liquid distributor 4a. In this case, the liquid phase F can be distributed over the tube bundle 3 via openings 40a in the tray 4.

(15) As is furthermore shown in FIG. 2, the roofs 52 are preferably arranged at the same height in the direction of the longitudinal axis z of the helically coiled heat exchanger 1 or of the shell 5 and each have an encircling edge region 52a with an encircling annular bottom edge 52b which, in relation to the longitudinal axis z, runs at the height of or below an encircling end side 50a of the respective chimney 50, which end side bounds the inlet opening 51 of the respective chimney 50. In this case, it is furthermore provided that the roof 52 of the respective chimney 50 projects, with the encircling edge region 52a, beyond the associated chimney 50 perpendicular to the axis L of the respective chimney 50. This ensure that, where possible, no liquid fraction F of the first medium M can pass into the respective chimney 50. This furthermore results in the gaseous phase G being diverted multiple times along its flow path in the direction toward the tube bundle 3, which improves the separation of the liquid phase F from the gaseous phase G.

(16) FIG. 3 shows a further embodiment of a helically coiled heat exchanger 1 according to the invention, in which the individual chimneys 50, 70 are basically formed in the manner of FIG. 2, wherein now, in contrast to FIG. 2, there are provided first chimneys 50 which, along the respective axis L, have a smaller height above the tray 4 than second chimneys 70. In this case, the first and second chimneys 50, 70 are arranged alternately, with the result that, owing to the different height of the respective roofs 52, 72, a larger number of chimneys 50, 70 are arrangeable on the tray 4 per unit area. This becomes clear in particular in that, with this arrangement of chimneys 50, 70 of different length, the spacing A of a second chimney 70 to the roof 52 of an adjacent first chimney 50 perpendicular to the axis L of the second chimney 70 is smaller than the protrusion A′ of the roof 52 of the adjacent first chimney 50 beyond said first chimney 50. In the case of roofs 52, 72 of the same height, the spacing between two adjacent chimneys 50, 70 perpendicular to their axes L would accordingly be larger. Apart from the different length, the first and second chimneys 50, 70 are specifically formed according to the exemplary embodiment in FIG. 2.

(17) Finally, FIG. 4 shows a further exemplary embodiment of a helically coiled heat exchanger 1 according to the invention, in which the chimneys 50 are formed in the manner of FIG. 2, wherein now, in addition, an inner chimney 60 is arranged in the respective chimney 50, formed here as an outer chimney, which inner chimney extends through the roof 52 of the respective outer chimney 50 and projects, with an upper portion 63, from the respective roof 52, wherein the upper portion 63 of the respective inner chimney 60 has an inlet opening 61 which is in turn covered by a roof 62 of the respective inner chimney 60 such that an encircling gap between the respective roof 62 and the inner chimney 60 arranged therebelow is again obtained.

(18) It is also possible for each of the inner chimneys 60 to be formed by an encircling cylindrical wall 60 which may, in the in each case surrounding outer chimney 50, extend downward to the height of the respective passage opening 40 of the tray 4, with the result that a lower outlet opening 41 of the respective inner chimney 60, which outlet opening faces the tube bundle 3, is situated in the opening plane of the respective passage opening 40.

(19) Correspondingly, the liquid phase F of a first medium M which is applied to the separating device 2 or the tray 4 from above can then flow off the roof 62 of the respective inner chimney 60 past the gap or the inlet opening 61 of the respective inner chimney 60 onto the roof 52 of the respectively associated outer chimney 50 and, from there, onto the tray 4, where it can be collected and further distributed over the tube bundle 3. By contrast, the gaseous phase G can further be conducted via the annular inlet openings 51 in the respective outer chimney 50 along the coaxial inner chimney 60 via the respective passage or outlet opening 40 to the tube bundle 3, wherein, owing to the inner chimneys 60, one additional flow path for the gaseous phase G is then present per outer chimney 50 since the gaseous phase G is then also able to be conducted via the inlet opening 61 of the respective inner chimney 60, situated below the roof 62 of the respective inner chimney 60, into the respective inner chimney 60 and, from there, via the outlet opening 41 of the respective inner chimney to the tube bundle 3.

(20) As already set out further above, the roof 62 of the respective inner chimney 60 preferably also has an encircling edge region 62a with an annular, downward pointing bottom edge 62b which runs at the height of or below an encircling, upward pointing end side 60a of the upper portion 63 of the respective inner chimney 60, which end side bounds the inlet opening 61 of the respective inner chimney 60.

(21) Owing to the coaxial arrangement of outer chimneys 50 and inner chimneys 60, it is, as per FIG. 4, advantageously possible for the separating device 2 to also be housed in shell portions 5a of the shell 5, the diameter or circumference of which shell portions continuously decreases toward the top in the direction of the longitudinal axis z.