SHELL-AND-TUBE HEAT EXCHANGER AND METHOD FOR CHANGING THE TEMPERATURE OF A MEDIUM

Abstract

The invention relates to a shell-and-tube heat exchanger for changing the temperature of a medium, having a plurality of channels of the tubes, an inlet chamber, an outlet chamber, and at least one channel of the shell for a further medium, wherein the medium can be conveyed into the inlet chamber and, from there, through at least a portion of the channels of the tubes into the outlet chamber, and having a closure means arranged on the outlet chamber and designed and adjustable in such a way that outlet openings of each subset of a plurality of different subsets of the channels of the tubes can be closed off. The invention also relates to a method for changing the temperature of a medium by means of a shell-and-tube heat exchanger.

Claims

1. A shell-and-tube heat exchanger for changing the temperature of a medium, having a plurality of channels of the tubes, an inlet chamber, an outlet chamber, and at least one channel of the shell for a further medium, wherein the medium can be conveyed into the inlet chamber and, from there, through at least a portion of the channels of the tubes into the outlet chamber, wherein a closure means arranged on the outlet chamber and designed and adjustable in such a way that outlet openings of each subset of a plurality of different subsets of the channels of the tubes can be closed off.

2. The shell-and-tube heat exchanger according to claim 1, wherein the outlet openings of all channels of the tubes are formed in an outlet plate with a planar surface, and wherein the closure means has at least one planar closure surface which rests on the surface of the outlet plate and is movable in a plane of the surface.

3. The shell-and-tube heat exchanger according to claim 2, wherein the at least one planar closure surface can be positioned over the outlet openings of the channels of the tubes to be closed off, in accordance with the channels of the tubes to be closed off.

4. The shell-and-tube heat exchanger according to claim 2, wherein the at least one planar closure surface is designed as one or more circular sectors.

5. The shell-and-tube heat exchanger according to claim 2, wherein a contour of the closure surface is adapted to a grid of the channels of the tubes.

6. The shell-and-tube heat exchanger according to claim 1, wherein the closure means comprises a plurality of closure pins, each of which can be introduced into one of the outlet openings.

7. The shell-and-tube heat exchanger according to claim 6, wherein the plurality of closure pins is designed in such a way that, according to the channels of the tubes to be closed off, it is possible to therewith close off only the outlet openings of the channels of the tubes to be closed off.

8. The shell-and-tube heat exchanger according to claim 6, wherein the outlet openings of all channels of the tubes are formed in an outlet plate with a planar surface, and wherein the plurality of closure pins is arranged on a closure plate which is arranged parallel to the planar surface and is movable relative to this surface.

9. The shell-and-tube heat exchanger according to claim 8, wherein the plurality of closure pins is divided into different subsets so that the closure pins of one subset each have the same length and the closure pins of different subsets each have a different length relative to the closure plate.

10. A method for changing the temperature of a medium by means of a shell-and-tube heat exchanger having a plurality of channels of the tubes, an inlet chamber, an outlet chamber, and at least one channel of the shell for a further medium, wherein the medium is conveyed into the inlet chamber and from there through at least a portion of the channels of the tubes into the outlet chamber, wherein a closure means arranged on the outlet chamber is adjusted according to the change in temperature in such a way that outlet openings of each subset of a plurality of different subsets of channels of the tubes are closed off therewith.

11. The method according to claim 10, wherein a shell-and-tube heat exchanger is used, the shell-and-tube heat exchanger for changing the temperature of a medium, having a plurality of channels of the tubes, an inlet chamber, an outlet chamber, and at least one channel of the shell for a further medium, wherein the medium can be conveyed into the inlet chamber and, from there, through at least a portion of the channels of the tubes into the outlet chamber, wherein a closure means arranged on the outlet chamber and designed and adjustable in such a way that outlet openings of each subset of a plurality of different subsets of the channels of the tubes can be closed off.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0017] FIG. 1 schematically shows a shell-and-tube heat exchanger according to the invention in a preferred embodiment.

[0018] FIGS. 2a, 2b, 2c and 2d show a portion of a shell-and-tube heat exchanger according to the invention in a preferred embodiment in different views.

[0019] FIGS. 3a and 3b show a portion of a shell-and-tube heat exchanger according to the invention in a further, preferred embodiment.

DETAILED DESCRIPTION OF THE DRAWING

[0020] In FIG. 1, a shell-and-tube heat exchanger 100 according to the invention is schematically shown in a sectional view in a preferred embodiment, which can be used for changing the temperature of a medium a, such as a synthesis gas which is supplied to the shell-and-tube heat exchanger 100, in particular, for cooling it. The basic principle of the shell-and-tube heat exchanger 100 here corresponds to a traditional shell-and-tube heat exchanger, as is also described in principle in the document cited at the outset.

[0021] The shell-and-tube heat exchanger 100 has a plurality of tubes or channels 110 of the tubes through which a medium a to be cooled is conveyed or routed. The channels 110 of the tubes are arranged in this case, by way of example, about a central axis R. For this purpose, the medium a is first supplied via an inlet opening 122 to an inlet chamber 120 and, from there, is conveyed through the channels 110 of the tubes into an outlet chamber 130. Via the outlet chamber 130, the medium can then be conveyed out of the shell-and-tube heat exchanger 100 again via an outlet opening 132. On the inlet chamber 120, the channels 110 of the tubes, or the tubes, are held in position by means of an inlet plate 124; on the outlet chamber 130, they are held by means of an outlet plate 134. In the inlet plate 124, the individual channels 110 of the tubes, or the tubes, have inlet openings or inlet orifices 126; in the outlet plate 134, they have corresponding outlet openings or outlet orifices 136.

[0022] The channels 110 of the tubes are surrounded by a shell 140. In the shell 140, a channel 142 of the shell is formed, through which a (further) medium b, in particular a cooling medium such as water, can be conveyed. For this purpose, the medium b can be introduced into the channel 142 of the shell through one or more inlet openings 146, which can be formed, for example, in the form of inlet nozzles (only one inlet opening is shown here by way of example). The medium b can then flow through the channel 142 of the shell and exit through one or more outlet openings 144, which can be formed, for example, in the form of outlet nozzles, out of the channel 142 of the shell (only one outlet opening is shown here by way of example).

[0023] The inlet openings 146 are distributed, for example, over the length of the shell-and-tube heat exchanger 100. The outlet openings 144 are, for example, likewise distributed over the length of the shell-and-tube heat exchanger 100. Usually, more medium b is supplied and discharged close to the inlet chamber 120, i.e., where the medium a is still warm. However, the specific embodiment of the channel of the shell or the way in which medium is conveyed therein is not relevant to the present invention.

[0024] Furthermore, a closure means 150 is provided on the outlet chamber 130 or arranged there and can close off portions or certain subsets of the outlet openings 136 of the channels 110 of the tubes. By way of example, the outlet openings 136 situated at the bottom in the sectional view are closed off, but the outlet openings 136 at the top are not. In this way, for example, half of all channels 110 of the tubes can be closed off in order to cool the medium a less than would occur in a situation in which all channels 110 of the tubes are open.

[0025] For the closure means 150, which may, for example, be a plate or a closure plate, or which may have such a plate, an actuator 154 is provided by way of example, by means of which the closure plate can be rotated in order to close a different subset of outlet openings 136. For this purpose, the actuator 154 can be controlled, for example, by means of a control device 156. For a more detailed description of the closure means 150 and its mode of operation, also in various embodiments, reference is made to the following figures with the associated description.

[0026] In FIGS. 2a, 2b, 2c and 2d, a portion of a shell-and-tube heat exchanger according to the invention is shown in various views in a preferred embodiment. The basic structure of the shell-and-tube heat exchanger can correspond to that of FIG. 1. In FIG. 2a, a portion of the outlet plate 134 and some of the channels of the tubes or outlet openings 136 therein are shown in a sectional view comparable to FIG. 1 (see also the axis R). It should be noted that the number of channels of the tubes or outlet openings 136 deviates from that in FIG. 1; however, this is not relevant for the explanation of the invention. In addition, a closure means 250 is shown, which is basically comparable to the closure means 150 indicated in FIG. 1.

[0027] FIG. 2b shows a frontal view toward the outlet plate 134 or its surface 238, shown from the outlet opening 132 (see FIG. 1). In this case, a hatching (crossed lines) indicates two regions in which the outlet openings 136 are arranged (the individual outlet openings are not shown here). These two regions correspond to two circular sectors, each with an angle of 90?, the shared point of which lies on the axis R. The two circular sectors are opposite one another, i.e., are uniformly offset from one another, as viewed in the circumferential direction.

[0028] In FIGS. 2c and 2d, to expand upon FIG. 2b, the closure means 260 is additionally shown. The closure means 250 has a closure plate 260 which, by way of example, has two planar closure surfaces 262 facing the outlet openings 136. These two closure surfaces 262 are each designed as circular sectors, each with an angle of 90?, the shared point of which lies on the axis R. They lie on the surface 238 of the outlet plate 136 and can be rotated about their shared point or the axis R, for example by means of an actuator 254 (see FIG. 2a).

[0029] In the position of the closure means 250 shown in FIG. 2c, none of the outlet openings 136 is closed off. In the position of the closure means 250 shown in FIG. 2d, the closure means is somewhat rotated and some of the outlet openings 136, i.e., a certain subset T thereof, are closed off. They are covered by the closure means or the closure surfaces 262. By rotating the closure means 250, different subsets of the outlet openings 136 can thus be covered or closed off, with different numbers of outlet openings in each case.

[0030] By means of a targeted arrangement of the channels of the tubes or the outlet openings thereof and the formation of the closure means, the subsets in this case can be selected individually. It is understood that the specific shape of the closure surfaces, and accordingly the arrangement of the outlet openings, can also be selected differently. A semicircular closure surface (i.e., a circular sector with 180?) is conceivable, for example. However, for example, (only) one closure surface as a circular sector with 90? is conceivable, with the outlet openings arranged in the form of a circular sector with 270?. Although only a maximum of one third of the outlet openings can then be closed off, this may be sufficient, for example, according to the application. Geometries of the closure surfaces deviating from circular segments, which are adapted, for example, to the grid of the channels 110 of the tubes, are also conceivable.

[0031] FIG. 3a is a portion of a shell-and-tube heat exchanger according to the invention in a further preferred embodiment. The basic structure of the shell-and-tube heat exchanger can correspond to that of FIG. 1. FIG. 3 shows only a portion of the outlet plate 134, and some of the channels of the tubes or outlet openings 136 therein, in a sectional view comparable to that of FIG. 1 (see also the axis R). It should be noted that the number of channels of the tubes or outlet openings 136 deviates from that in FIG. 1; however, this is not relevant for the explanation of the invention.

[0032] In addition, a closure means 350 is shown which has a closure plate 360 on which a plurality of closure pins 362 is arranged. The closure pins 362 are oriented parallel to the axis R and are designed, for example, with a rod shape or, where applicable, conically tapering (with slightly decreasing diameter from the right to the left as seen in FIG. 3). It should be noted here that a diameter of the closure pins can be slightly smaller than a diameter of the corresponding channels of the tubes in order to enable a displacement. Sealing due to high flow resistance is thus nevertheless possible.

[0033] Each of the closure pins is thus assigned to an outlet opening 136 and can be inserted into the latter. This is done by displacing the closure plate, for example by means of an actuator 354, along the axis R. The closure pins 362 can thus be brought into and out of the outlet openings 136 or the channels of the tubes.

[0034] As can be seen in FIG. 3a, the closure pins 362 are of different lengths, as viewed in the direction of the axis R. This makes it possible, according to the position of the closure plate along the axis R, to close off a different number or subset T of the outlet openings. In the example shown, the two outlet openings next to the axis R, and also the two outlet openings following below them, are closed off. The last four outlet openings at the bottom (in the view in FIG. 3) are not closed off.

[0035] FIG. 3b shows a frontal view toward the outlet plate 134 or its surface 238, from the outlet opening 132 (see FIG. 1). The seven rows, as seen downward from the axis R (in FIG. 3a), are seen here from the center (the two middle rows in the common center) outward. By way of example, the arrangement here is non-circular but along the edges of a hexagon.

[0036] If the closure plate 360 with the closure pins 362 is now moved further in the direction of the outlet plate 134, the fourth outlet opening from the bottom (or the fourth row of the outlet openings from the outside according to FIG. 3b) is then the next to be closed off. Thereafter, the third outlet opening from the bottom is also closed off. If, on the other hand, the closure plate 360 with the closure pins 362 is moved away from the direction of the outlet plate 134 (starting from the situation in FIG. 3), then the fifth outlet opening from the bottom, and thereafter the sixth outlet opening from the bottom, and finally all the outlet openings are opened.

[0037] In this way, certain subsets of the outlet openings, which are closed off one after the other by the displacement of the closure means 360, can thus be specified as desired. For this purpose, it is only necessary to select the length of the closure pins 362 accordingly. Closure pins with the same length close the outlet openings assigned to them, at the same time. Depending on requirements, such closure pins with the same length can be arranged, for example, rotationally symmetrically with respect to the axis R.

[0038] It is conceivable, as is also shown here, that certain outlet openings may not be closed off at all, for example because the closure plate 360 does not cover all the outlet openings. It is also conceivable that, when the closure plate 360 rests on the outlet plate 134, outlet openings are closed off without closure pins.