DE20219278U1 - Annular channel for external supply and return of heat exchange medium to vertical tube reactor, has openings equipped with flow controls - Google Patents

Abstract

Opening(s) (34) are equipped with flow controls. Preferred Features: The opening height is 0.05 x to 1 x the available height, i.e. the height of the annular channel or spacing between tube bases and the adjacent deflection baffle (22). Individual openings along the reactor circumference are most preferably 0.5-0.65 times the opening interval along it. Opening (34) geometry varies around the circumference. Opening(s) near the inlet are small, becoming larger and then smaller, further away from it. Flow control is by deflection baffles. Connections for valves and a circulation pump are provided. An expansion joint runs around the reactor casing.

Description

Ring channel for the supply and removal of the heat transfer medium in a jacket tube reactor

The invention relates to an annular channel according to the preamble of patent claim 1.

A shell-and-tube reactor is a fixed bed reactor that offers the possibility of bringing about a heat exchange between the process gas mixture reacting in the fixed bed within the shell-and-tube reactor and between the shell-and-tube reactor itself and a separate heat transfer medium. In principle, the reaction can be either endothermic or exothermic. The shell-and-tube reactor - essentially a granular catalyst - is located in the tubes (reaction tubes) of a generally vertically arranged reaction tube bundle, both ends of which are sealed in tube plates and which are surrounded by the heat transfer medium within a reactor shell surrounding the tube bundle. The process gas mixture is fed to the tubes via a reactor hood spanning the relevant tube plate and is also discharged via a reactor hood spanning the other tube plate. The heat transfer medium - often a salt bath - is circulated by a circulation pump and heated or cooled by a heat exchanger depending on the type of reaction process. Nowadays, the pump and heat exchanger are usually located outside the reactor shell. Accordingly, the heat transfer medium enters the reactor shell near one tube sheet and exits it near the other tube sheet. In order to achieve a certain temperature profile along the reaction tubes that is desirable for the reaction, entry and/or exit points for the heat transfer medium can also be located in intermediate levels of the reactor shell.

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In order to obtain as uniform a temperature profile as possible for all the tubes in the reactor - a modern jacketed tube reactor can contain up to 30,000 tubes or more - in the interests of a uniform reaction process and thus a high yield and good selectivity of the reaction product, it is important to keep temperature differences in the heat transfer medium within the reactor jacket small and, above all, to create as uniform flow conditions as possible for all the tubes. For this purpose, ring channels have been created for the supply and removal of the heat transfer medium to and from the reactor jacket, which are connected to the inside of the jacket via a ring of windows. Various flow-influencing fittings, such as distributor and/or deflection plates, are usually provided inside the jacket to support this. Special designs of such fittings and other measures in the same sense form the subject of the parallel utility model application 202 19 277.6 "Jacket-and-tube reactor for catalytic gas phase reactions" by the same applicant.

In principle, temperature differences in the heat transfer medium can be kept small by maintaining a high flow velocity within the reactor, but the pumping capacity required for this sets limits.

Ring channels on jacketed tube reactors are known, for example, from DE-A-I 601 162. It is also known (cf., for example, EP 1 08 0 78 0 and EP 1 080 781) to vary the size, spacing and/or arrangement of the windows on ring channels according to the pressure profile occurring in the ring channel. DE-A-34 09 159 also teaches connecting each ring channel to several pumps distributed over the circumference of the reactor. According to DE-A-43 26 643, the ring channels can have a cross-section that decreases from the respective pump connection point in order to thus adjust the flow conditions in the ring channel with regard to the partial quantities discharged or added through the windows.

Furthermore, a ring channel on the heat transfer medium inlet side can be divided by a horizontal partition wall into two areas one above the other, each of which communicates with the interior of the reactor and is connected to one another via controllable openings. However, the measures in question can still be supplemented, both in terms of manufacturability and efficiency.

Based on this, the invention is based on the task of further improving the profitability of ring channels in shell-tube reactors.

This object is achieved according to the invention primarily with the features of patent claim 1. The subclaims specify advantageous design options and further developments based thereon.

The flow-influencing means in question give the ring channel an additional function. If they are in the form of guide surfaces, a type of guide wheel is created - in the language of turbine builders - through which the heat transfer medium flow can be optimally adjusted in vector terms, i.e. in terms of direction and size, across the entire reactor circumference. In this way, lower throttling losses can be achieved. In addition, the desired distribution of the heat transfer medium across the reactor circumference can be achieved better and more precisely.

If the flow-influencing means appear in the form of a grid on the ring channel on the heat transfer medium inlet side, a turbulent flow can be achieved for the outermost rows of tubes in the reaction tube bundle, but also an inlet of the heat transfer medium that is distributed regularly over the circumference in the desired manner. In either case, by specifically distributing the heat transfer medium over the circumference of the reaction tube bundle,

Different flow resistances can be compensated for by the different tube bundles, such as those caused by different tube coverages in different radial axial directions (tubes aligned with one another or more or less offset from one another). More details on this can be found in the aforementioned parallel utility model application 202 19 277.6 "Jacket tube reactor for catalytic gas phase reactions".

Advantageous embodiments and developments of the invention are described in more detail below with reference to the figures. These show:

Fig. 1 shows a somewhat schematic longitudinal section through a jacketed tube reactor with ring channels,

Fig. 2 a cross-section through the shell of a shell-tube reactor at the level of the heat transfer medium inlet side ring channel including circulation pump and heat exchanger,

Fig. 3 and Fig. 4 each show a cross-section similar to Fig. 2, but with guide surfaces in the form of blades on or between the casing windows of an annular channel,

Fig. 5, Fig. 6 and Fig. 7 different blade shapes on the casing windows of a ring channel,

Fig. 8 a cross-section through a heat transfer medium inlet side ring channel with built-in mixer,

Fig. 9 shows a cross-section through a ring channel with a mixer on the heat transfer medium inlet side, the ring channel being divided into two sections running one above the other by a substantially horizontal wall,

Fig. 10 a cross-section through a similarly divided ring channel with mixer, but the mixer is arranged inside the reactor,

Fig. 11, Fig. 12 and Fig. 13 each show a diagram of a jacketed tube reactor with two circulation pumps connected to it,

Fig. 14 is a cross-section similar to that of Fig. 2, but with the annular channel tapered away from the heat transfer medium inlet point by an eccentric circular cylindrical wall,

Fig. 15 is a cross-section similar to that of Fig. 14, but with the annular channel itself arranged eccentrically with respect to the reactor shell,

Fig. 16 a detail of a cross-section similar to that of Fig. 15 in the inlet area of the heat transfer medium,

Fig. 17 a detail of a cross-section similar to Fig. 16, but with a differently designed heat transfer fluid inlet area,

Fig. 18 a cross-section similar to Fig. 2 with an asymmetrically divided ring channel,

Fig. 19 a detail of a longitudinal section of a double-walled reactor shell with an annular channel arranged between its two walls,

Fig. 20 a detail of a longitudinal section of a reactor shell with internal ring channel,

Fig. 21 is a view similar to Fig. 1 of the upper section of a jacketed tube reactor with an annular pipe feeding an internal ring channel from the outside via a distribution channel,

Fig. 22a) and b) a cross-section and a detail of a longitudinal section of an annular channel with a continuous window forming an expansion joint,

Fig. 23a) and b) a cross-section and a detail of a longitudinal section of a ring channel with an expansion joint running through individual windows,

Fig. 24a) and b) a cross-section and a detail of a longitudinal section of a ring channel with an expansion joint running below the windows,

Fig. 25 a cross-section of a ring channel with expansion joint, which is divided by a partition plate into two superimposed, quasi-independent ring channels, and

Fig. 2 6 shows a broken-off reactor longitudinal section showing the support of a jacketed tube reactor by means of struts penetrating ring channels.

Fig. 1 shows a jacketed tube reactor 2 with an upright, ring-shaped reaction tube bundle 6 surrounded by a cylindrical reactor jacket 4, the tubes (reaction tubes) 8 of which are held in a sealing manner at both ends in tube plates 10 and 12. Reactor hoods 14 and 16 extend over both tube plates to facilitate the inlet and outlet of the process gas reacting in the tubes 8.

Each of the tubes 8 is essentially filled with a granular catalyst (not shown) and is surrounded by a heat transfer medium (also not shown) - usually a molten salt, but sometimes also water or another liquid heat transfer medium - which is circulated by a circulation pump (not shown) arranged outside the reactor jacket 4 through

is circulated through the reactor jacket 4 and passes through a heat exchanger (heater or cooler) in the main or bypass connection to the circulation pump.

The heat transfer medium is fed to and removed from the reactor shell 4 via ring channels 18 and 20 near the tube sheets 10 and 12. In order to give the heat transfer medium a substantially transverse, i.e. radial, flow path with respect to the tube bundle 6, which is preferable in most cases for reasons of better heat exchange between the heat transfer medium and the tubes 8, there are alternating ring and disk-shaped deflection plates 22 and 24 within the reactor shell 4 in planes between the ring channels 18 and 20, through which the tubes 8 at least mostly pass. The deflection plates 22 and 24 can, as shown, have partial flow openings 26 through which partial flows of the heat transfer medium pass, in order to create as equal as possible flow conditions on all tubes 8.

Overall, in the example shown, the heat transfer medium flows through the reactor 2 from bottom to top, i.e. in the opposite direction to the reaction gas, but a flow in the same direction is also conceivable and sometimes appropriate, just as the reaction gas can flow through the reactor from top to bottom or from bottom to top.

Fig. 2 shows a horizontal cross section through the reactor shell 4 within a ring channel 30 on the heat transfer medium inlet side, similar to the ring channel 20 from Fig. 1. The inner wall 32 of the ring channel 30 is formed by the reactor shell 4, which has a ring of windows 34 for the passage of the heat transfer medium. In the example shown, the ring channel 30 is divided at the heat transfer medium inlet by a vertical separating plate 36, and both sections 38 and 40 thus formed are connected via a branched line 42 to a line outside the reactor.

The ring channel 30 is connected to a circulation pump 44 for the heat transfer medium located outside the reactor, while the opposite side of the ring channel 30 is connected via a common line 46 to a heat exchanger 48, e.g. cooler, for the heat transfer medium, also located outside the reactor. There too, a separating plate similar to the separating plate 36 can be advantageous in order to stabilize the flow.

As explained in EP 1 080 780 A1, the windows within one and the same annular channel can vary in many ways in order to take account of the optimal flow conditions at each point when passing through the reactor shell. For example, the windows can appear in one or more rows, whereby their size, contour and/or spacing can vary from row to row as well as over the circumference of the reactor.

As can be seen, the heat transfer medium from the ring channel 30, where it is forced to take a substantially tangential course with respect to the reactor shell 4, enters the reactor shell through the windows 34 with a necessarily strong radial component. The same applies if the heat exchanger, as used in some cases, is arranged in parallel to the circulation pump 44 and as a result there is no outlet for the heat transfer medium on the side of the ring channel opposite the pump. Since the heat transfer medium in the tube bundle 6 of the reactor 2 is to take a substantially radial course, it would be expedient to give the heat transfer medium flow a radially directed course with respect to the reactor center axis as soon as it exits the windows 34. In the ring channel on the heat transfer medium outlet side, such as the ring channel 18 according to Fig. 1, similar conditions exist with the flow direction reversed. Either way, the windows 34 represent throttling points for the heat transfer medium. In any case, this creates an energy loss with regard to the flow of the heat transfer medium.

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which has to be compensated by the performance of the circulation pump 44.

According to the invention, flow guide means in the form of blades 50, 52 and 54 forming guide surfaces are now provided on the windows 34 according to Figures 3 and 4 on the inside and/or outside of the reactor shell 4, which support the deflection of the flow and make it less loss-intensive. On the outside, within the respective ring channel, the respective blades 50 and 54 assume a position inclined in the flow direction of the heat transfer medium, while the inside blades 52 according to Figure 3 are directed essentially radially.

Figures 5-7 show, greatly enlarged, various practical designs of the blades described above for the ring channel 30 on the heat transfer medium inlet side. While the blades 56 according to Fig. 5 have an ideal shape which, together with the side walls 58 and 60 of the windows 34, form continuously expanding nozzle-like channels 62, Fig. 6 represents an approximate solution with angled blades 64 made of sheet metal. Finally, Fig. 7 shows, in addition to the blades 64 from Fig. 6, a plurality of blades 66 running through the respective window 34, which, in addition to a more or less continuous deflection, cause a spreading of the heat transfer medium flow entering the reactor shell 4. The blades 64, like the blades 66, can be part of a sheet 68 which is welded onto the reactor shell 4 and, in the case of perforations, can even extend beyond the windows 34. Such "grids" will be discussed in more detail later.

Fig. 8 shows a blade such as 64 or 66 inside a heat transfer medium inlet-side ring channel 70, which on the one hand rests against the lower channel wall 72, on the other hand, possibly together

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men with further blades, is covered on the upper side by a cover plate 74 in order to form a closed flow channel.

Preferably, the window height is 0.05 to 1.0 times the available height, such as the annular channel height or the distance between the tube sheet and the adjacent baffle, and the window width is 0.1 to 0.9 times the window pitch, whereby the window pitch will be < 600 mm.

Generally, the window cross-section and geometry of the flow-influencing means according to the invention, such as blades or grids, are already determined when dimensioning an annular channel. In general, the attempt is made to make the window cross-section as large as possible. However, all or just some of the parameters just mentioned can be varied over the reactor circumference.

Fig. 9 shows a mixer 78 within an annular channel 80, which is divided into two overlapping sections 84 and 86 by a spirally inclined partition wall 82, approximately as shown in Fig. 13. Of course, an arrangement similar to that shown in Fig. 9 can also be used when using a horizontal partition wall 82 located approximately halfway up the wall, as shown in Figs. 11 and 12. The mixer 78 is fed from the two sections 84 and 86 through openings 88 on the top and bottom, and has a perforated wall 90 in the area of the windows 34 of the annular channel, which serves as a mixing, flow distribution and/or turbulence grid and can be multi-layered if desired. While a flow distribution grid can bring about a desired flow distribution or orientation in the axial and, above all, tangential direction of the reactor, a turbulence grid primarily serves to give the heat transfer medium a turbulent flow as soon as it enters the reactor.

More details on this can be found in the already mentioned parallel utility model application 202 19 277.6 "Jacket tube reactor for catalytic gas phase reactions", to which reference is made in this regard. In the simplest case, the perforated wall 90 can consist of a standardized perforated sheet.

In general, a perforated wall or plate, such as a perforated sheet, can be used to increase the window cross-section in a manner that is often desirable, thus making the inflow to the interior of the reactor shell more uniform. In addition, this always promotes, i.e. accelerates, the formation of a turbulent flow, which should be used without exception for the pipe flow to achieve good heat transfer. Under certain circumstances, the perforation can also be provided in place of individual windows in the reactor shell 4. By selecting the hole size, the hole spacing and, if necessary, the hole direction, it is possible to create different inflow conditions, especially along the circumference of the reactor, if desired, as is explained in more detail in the parallel utility model application 202 19 277.6 "Jacket tube reactor for catalytic gas phase reactions" mentioned above. Otherwise, the same hole sizes, hole spacing, etc., as well as the same window sizes, window spacing, etc. can be used if the variation of the ring channel cross-section ensures that the same flow speeds prevail in all cross-sections of the ring channel. Otherwise, pressure differences (static and dynamic) along the ring channel can be compensated not only by the choice of window geometry but also by the choice of grid parameters, if grids such as perforated walls are present, or by the choice of blade geometry, such as dimensions, spacing, inclination, curvature or profile.

According to Fig. 10, in an embodiment with overlapping ring channel sections 84 and 86, a mixer 92 in the form of a ring channel is attached to the inside of the reactor shell 4, overlapping the respective windows 34. Here again, the outlet of the mixer can be formed by a grid similar to the perforated wall 90. However, blades similar to the blades 64 and/or 66 from Fig. can also be provided.

Fig. 11 shows an example of a jacketed tube reactor 2 with overlapping ring channel sections 84 and 86 on the heat transfer medium inlet side and on the heat transfer medium outlet side ring channel 20 and 18, respectively. Here, the two ring channels are connected to two circulation pumps 44 at diametrically opposite points, but in between to a common heat exchanger 48, which feeds into the two overlapping sections 84 and 86 of the heat transfer medium outlet side ring channel 18 via a conveniently continuously adjustable three-way valve 98. The valve 98 can have the shape of a flap. The two ring channel sections 84 and 86 can, as shown, be separated by means of an exactly horizontal partition 82 and two vertical partitions 94 and 96 and have consistently identical cross-sections.

Fig. 12 shows an example, otherwise like that of Fig. 11, in which only the ring channel on the heat transfer medium inlet side is divided by horizontal and vertical partitions 82, 94 and 96, but the other one according to Fig. 2 has a simple vertical partition 36 in the feed area. According to Fig. 13, the ring channel on the heat transfer medium inlet side can have two ring channel sections 84 and 86 separated from each other by a spirally inclined partition 82 - as described in DE-A-43 26 643, but for both ring channels - and possibly running one above the other over half the reactor circumference. Note-

It is noteworthy that such a design only offers advantages in terms of flow technology in the ring channel on the heat transfer medium inlet side. In addition, the valve 98 in this example can usually be omitted without any disadvantage, since the two heat transfer medium flows fed into the reaction vessel via the ring channel sections 84 and 86 mix sufficiently.

Otherwise, the two ring channel sections 84 and 86 and/or 38 and 40 can have temperature sensors (not shown) which automatically control the amount of heat transfer medium fed into the ring channel sections via the three-way valve 98 according to the temperature difference determined thereby.

Even when using a single circulation pump 44, it may be expedient to reduce the cross-section of the ring channel, if possible already away from its feed point, in order to obtain as constant a flow velocity as possible within the ring channel. In this case, it may even be unnecessary to vary the size, distance, etc. of the windows 34 over the circumference of the reactor. Rational solutions for such a change in cross-section are shown in Figures 14 and 15. According to Figure 14, an essentially circular-cylindrical, upright partition wall 104 is mounted eccentrically within a conventional ring channel 102 of constant rectangular cross-section. In this way, too, two overlapping ring channel sections similar to sections 84 and 86 from Figure 13 could be created when using two diametrically opposed circulation pumps. According to Fig. 15, a circular cylindrical ring channel 108 with a rectangular cross-section is arranged eccentrically to the reactor shell 4. In addition, the heat transfer medium supply to the ring channel 108 according to Fig. 15 is designed to be flow-optimized by rounding.

Similar heat transfer medium feeds are shown in Figures 16 and 17. According to Fig. 16, a tongue 114 with passage openings 116 for the passage of a partial flow of the supplied heat transfer medium is arranged at the heat transfer medium inlet 110 on the ring channel, which thus also finds access to the interior of the reactor shell 4 through the windows 34 in the area of the tongue 114. In addition, there are suitably curved guide plates 118 on both sides of the tongue 114 and, on the inflow side in front of the tongue 114, a mixing grid 120. Instead of equipping the tongue 114 with passage openings such as 116, it could also be made correspondingly narrow, as indicated by dashed lines in Fig. 16, in order to find space between the first two ring channel windows 34 as seen from the central axis 122 of the heat transfer medium inlet 110.

According to Fig. 17, instead of a tongue, there is a channel 124 which is open on the inflow side and widens like a trumpet towards the reactor shell 4 for receiving a partial flow of the supplied heat transfer medium.

Fig. 18 shows how, in an otherwise conventional ring channel 130, two ring channel sections 134 and 136 of unequal length can be formed by a vertical separating plate 132 similar to the separating plate 36 from Fig. 2 in order to take into account the partial flow discharged from the ring channel section 134 to the heat exchanger 48 in this example.

In general, heat exchangers such as heaters, coolers or superheaters can be connected to the annular channel at any circumferential point in relation to the heat transfer medium inlet or outlet. It is always advisable to use guide plates such as guide plates 18 and/or tongues such as tongue 114 from Fig. 16 or a trumpet-like channel such as channel 124 from Fig. 17, at least as far as the heat transfer medium return from the heat exchanger is concerned.

It is understood that each ring channel has means for emptying the heat transfer medium contained therein at its lowest point, such as holes or gaps in the reaction jacket in addition to the windows 34.

Fig. 19 shows how an otherwise conventional ring channel, which can of course be equipped with all possible features, as described above, can be implemented in a double-walled reactor shell 138. Here, outside the usual reactor shell 4, a thinner wall 140 is located coaxially with it. Between them, an annular channel 142 is divided by annular upper and lower limiting plates 144 and 146, which is connected to the reactor interior in the usual way via windows 34 in the shell 4. The space 148 between the shell 4 and wall 140 above or below the limiting plates 144 and 146 can be used to accommodate the usual thermal insulation but also for possible bypass channels, as shown in the parallel utility model application 202 19 277.6 "Jacket tube reactor for catalytic gas phase reactions" already mentioned several times. If such bypass channels are to be connected directly to the ring channel 142, one of the limiting plates can be interrupted, as shown in the example of the limiting plate 146.

Fig. 20 shows how an annular channel 150 can be arranged inside the reactor shell 4 between the latter and the tube bundle 6. In this case, the annular channel can be designed to be particularly light, since it will not be exposed to any significant pressure difference. Accordingly, the radially inner wall 152 of the annular channel 150 can, if desired, be completely perforated similarly to the wall 90 in Fig. 9, e.g. in the form of a perforated plate, and thus designed as a grid.

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An internal ring channel, such as ring channel 150, is particularly suitable where the heat transfer medium is under high pressure, as is often the case in the case of water as a heat transfer medium, which is pressurized to achieve a higher boiling temperature.

Figure 21 shows how such an internal ring channel 150 can be fed for optimum distribution of the heat transfer medium via a pipe 152 running in a ring around the reactor shell and from this connecting pipe sockets 154 distributed over the reactor circumference, whereby an annular distribution channel 156, also located within the reactor shell 4, can also be connected upstream of the ring channel. In this case, the two channels 150 and 156 are connected via throttle openings 158 distributed all around, just as throttle openings 159 can also be provided in the connecting pipe sockets 154. Due to the high heat transfer medium overpressure outside the reactor shell 4, the annular pipe 152 and the connecting connecting pipe sockets 154 expediently have circular cross-sections, as shown. Moreover, their cross-sections, as well as those of the throttle openings such as 158, can vary according to flow distribution considerations. Otherwise, the throttle openings 158 can also vary in their mutual distance.

A similar arrangement can of course also be used in conjunction with a ring channel on the heat transfer medium outlet side. At lower heat transfer medium pressures, an essentially conventional ring channel on the outside can be used instead of a ring-shaped outside pipe with connecting pipe sockets, which communicates with an inside ring channel such as 150 directly or indirectly via a distribution channel such as 156.

Figures 22 - 25 show an additional use of an annular channel, namely to efficiently implement an expansion compensator to compensate for different thermal expansions of the tube bundle 6 and the reactor shell 4. In the cases shown here, such an expansion compensator is designed as a circumferential interruption of the reactor shell 4 - hereinafter referred to as an expansion joint - within an annular channel 160, the comparatively thin walls 162, 164 and 166 of which absorb the expansion in question predominantly in the form of bending.

According to Fig. 22, such an expansion joint 168 itself forms a single window 34 that runs through the reactor periphery and can vary in height. According to Fig. 23, the expansion joint can be covered by a cover plate 170 that is welded on only on one side. Otherwise - with the exception of Fig. 22 - it is expediently provided at a location where it has as little impact as possible on the desired flow pattern. For example, the expansion joint 168 can be arranged immediately adjacent to a tube sheet or a separating plate that divides the reactor into superimposed zones.

Insofar as the expansion joint 168 according to Fig. 23 runs through the annular channel windows 34 or forms one itself according to Fig. 22, flow guide means such as blades or grids or even tongues such as the tongue 114 may of course only be welded to the reactor shell 4 on one side - above or below the expansion joint.

Fig. 25 shows an expansion joint 168 located outside the relevant windows 34 in an annular channel 176 consisting of two sections 172 and 174 lying one above the other, which basically form independent annular channels. In this case, the edge of a separating plate 178 protrudes through the expansion joint 168 with play to the outside, where it is inserted into the outer wall 180 of the

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ring channel 176. In this way, the separating plate 178 is supported largely stress-free in both the axial and radial directions, since the relatively thin ring channel wall can deform sufficiently. In addition, it can have a reduced wall thickness in the same edge area, as shown.

As can also be seen in Fig. 25, the separating plate can carry a thermal insulation layer 182 on one or both sides up to the annular channel 176, which can also extend partially over the outer wall 180. In principle, a tube sheet such as e.g. or 12 can also take the place of the separating plate 178.

As can be seen from Fig. 25, the ring channel 176 - and the same applies to each ring channel in question here - can have gas extraction elements at suitable locations in order to be able to remove gas accumulating in the heat transfer medium or carried along by it and thus ensure the desired flow of the heat transfer medium. The gas extraction elements 184 in question can, if desired, also be connected to a common gas discharge line 186, possibly together with those within the reactor shell and, if necessary, via throttle elements (not shown). On the other hand, gas extraction elements such as the gas extraction element 184 shown in dashed lines in Fig. 25 can also be connected to the interior of the shell via through holes 188 or can be formed by such.

It is understood that at least many of the measures described above individually using various embodiments can also be implemented together in order to create an annular channel that is optimal in every respect. Such a channel can be used to advantage in a wide variety of jacketed tube reactors and sometimes also coolers, including

Shell-and-tube reactors with more than two ring channels and multi-zone reactors, and independent of the type of reaction process, the flow direction and the type of heat transfer medium.

Fig. 26 shows how a jacketed tube reactor 2, in this example a two-zone reactor with immediately adjacent ring channels 18 and 20 for both zones, can be supported radially outside the reactor shell 4. In this case, the force is introduced into the reactor shell 4 via struts 190 which pass through the ring channels 18 and 20 of the upper zone and which in turn are supported on support columns 194 outside the ring channels 18 and 20 of the lower zone via vertical intermediate members 192. Such a support of the reactor has the advantage that the lower reactor hood can be removed without hindrance, for example to change the catalyst. The struts 190 have the shape of metal sheets which, if they are wider, follow the curvature of the ring channel and can also have a flow-optimized profile. They are taken into account when calculating the ring channel cross-section, etc. In principle, such struts can also be used advantageously in single-zone reactors and those with ring channels that are not directly adjacent to one another, whereby the struts 190 can also run partially outside of a ring channel.

Claims (62)

1. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) for the external supply and removal of the heat transfer medium in a jacket tube reactor ( 2 ) with a reaction tube bundle ( 6 ) surrounded by the heat transfer medium within a reactor jacket ( 4 ; 138 ), the annular channel having at least one window ( 34 ) radially on the inside along the jacket circumference for the passage of the heat transfer medium, characterized in that the window or windows ( 34 ) is or are equipped with flow-influencing means ( 50-56 ; 64 ; 66 ; 68 ; 78 ; 90 ; 92 ). 2. Ring channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to claim 1, characterized in that the window height is 0.05 to 1.0 times the available height - ring channel height or distance between tube sheet ( 10 , 12 ) and adjacent baffle plate ( 22 ). 3. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to claim 1 or 2 with individual windows ( 34 ) along the reactor circumference, characterized in that the window width is 0.1 to 0.9 times, preferably 0.3 to 0.7 times and most suitably 0.5 to 0.65 times the window pitch in the reactor circumferential direction. 4. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to one of the preceding claims, characterized in that the geometry of the window or windows ( 32 ) and/or the flow-influencing means ( 50-56 ; 64 ; 66 ; 68 ; 78 ; 90 ; 92 ) varies over the reactor circumference. 5. Heat carrier inlet-side annular channel ( 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to claim 4, characterized in that the first or two first windows ( 32 ) in the region of the heat carrier inlet into the annular channel are relatively small, followed by a series of initially larger windows which become smaller away from the heat carrier inlet point. 6. Annular channel ( 30 ) according to one of the preceding claims, characterized in that the flow-influencing means consist at least partially of guide surfaces guiding the flow through the window or windows ( 34 ). 7. Annular channel ( 30 ) according to claim 6, characterized in that the guide surfaces are at least partially formed by blades ( 50-56 ; 64 ; 66 ) arranged on or in the window ( 34 ). 8. Annular channel ( 30 ) according to claim 7, characterized in that the blades ( 56 ) are at least partially aerodynamically profiled. 9. Annular channel ( 30 ) according to claim 7 or 8, characterized in that the blades ( 50 ; 54 ; 56 ; 64 ) are at least partially connected to the window or windows ( 34 ) on the outside. 10. Annular channel ( 30 ) according to one of claims 7 to 9, characterized in that the blades ( 52 ) at least partially adjoin the window or windows ( 34 ) on the inside. 11. Annular channel ( 30 ) according to one of claims 7 to 10, characterized in that the blades ( 66 ) at least partially penetrate the window or windows ( 34 ). 12. Annular channel ( 30 ) according to one of claims 7 to 11, characterized in that the blades ( 50 ; 54 ; 56 ; 64 ) are covered on the upper and/or lower sides by a cover plate ( 74 ) or a channel wall ( 72 ). 13. Annular channel ( 30 ) according to one of claims 6 to 11 with several windows ( 34 ), characterized in that the guide surfaces are at least partially formed by correspondingly profiled side walls (58, 60) of the windows ( 34 ). 14. Ring channel ( 30 ) according to one of claims 6 to 13, characterized in that the channels ( 62 ) between the guide surfaces vary over the reactor circumference. 15. Ring channel ( 30 ) according to one of claims 6 to 14, characterized in that the channels ( 62 ) between the guide surfaces are profiled like nozzles. 16. Annular channel ( 30 ) according to claim 15, characterized in that the channels ( 62 ) widen on the downstream side. 17. Annular channel ( 30 ; 80 ; 150 ) according to one of the preceding claims, characterized in that the flow-influencing means consist at least partially of a grid ( 68 ; 90 ; 152 ). 18. Annular channel ( 30 ; 80 ; 150 ) according to claim 17, characterized in that the grid ( 68 ; 90 ; 152 ) consists at least partially of a perforated wall. 19. Annular channel ( 30 ; 80 ; 150 ) according to claim 17 or 18, characterized in that the grid ( 68 ; 90 ; 152 ) is designed as a turbulence grid to create turbulence. 20. Annular channel ( 30 ; 80 ; 150 ) according to one of claims 17 to 19, characterized in that the grid ( 68 ; 90 ; 152 ) is at least partially designed according to flow distribution aspects. 21. Annular channel ( 30 ; 80 ; 150 ) according to claim 20, characterized in that the permeability of the grid ( 68 ; 90 ; 152 ) varies over the reactor circumference. 22. Annular channel ( 30 ; 80 ) according to one of claims 17 to 21, characterized in that the grid ( 68 ; 90 ) is at least partially formed in the reactor shell ( 4 ). 23. Annular channel ( 30 ; 80 ; 150 ) according to one of claims 17 to 22, characterized in that the grid ( 68 ; 90 ; 152 ) is multi-layered. 24. Annular channel ( 142 ) according to one of the preceding claims, characterized in that it is formed between the inner and outer walls ( 4 , 140 ) of a double-walled reactor shell ( 138 ). 25. Annular channel ( 150 ) according to one of claims 1 to 23, characterized in that it is arranged on the inside of the reactor shell ( 4 ). 26. Annular channel ( 150 ) according to claim 25, characterized in that its inner wall ( 152 ) is itself at least partially designed as a grid. 27. Annular channel ( 150 ) according to claim 25 or 26, characterized in that it communicates with a pipeline ( 152 ) running in a ring around the reactor shell ( 4 ) via a plurality of connecting pipe sockets ( 154 ) distributed all around. 28. Annular channel ( 150 ) according to claim 27, characterized in that there are pressure openings - possibly different ones - in the connecting pipe sockets ( 154 ). 29. Ring channel ( 150 ) according to claim 25 or 26, characterized in that it communicates through the reactor shell ( 4 ) with an external ring channel. 30. Ring channel ( 150 ) according to one of claims 25 to 29, characterized in that a distribution channel ( 156 ) is arranged upstream or downstream of it, which is also located in the interior of the reactor shell ( 4 ), which communicates with it via a plurality of throttle openings ( 158 ) distributed all around - possibly different or arranged at different densities to one another. 31. Annular channel ( 130 ) according to one of the preceding claims, characterized in that it has asymmetrically arranged connections for circulation pump ( 44 ) and heat exchanger ( 48 ). 32. Annular channel ( 130 ) according to claim 31, characterized in that it is divided by a separating plate ( 132 ) which, viewed from the connection of the circulation pump ( 44 ), separates a longer connection-free section ( 136 ) from a shorter section ( 134 ) having the connection for the heat exchanger ( 48 ). 33. Ring channel ( 18 , 20 ) according to one of claims 1 to 30 with two ring channel sections ( 84 , 86 ) which are essentially separate from one another and each connected to its own circulation pump ( 44 ), characterized in that the two ring channel sections overlap one another. 34. Annular channel ( 18 , 20 ) according to claim 33, characterized in that the overlap occurs in a range between 1% and 100%, preferably between 30% and 100% and most suitably between 50% and 100% of the reactor circumference. 35. Ring channel ( 18 , 20 ) according to claim 34, characterized in that the two ring channel sections ( 84 , 86 ) occupy the full ring channel cross-section in the remaining region. 36. Annular channel ( 18 , 20 ) according to one of claims 33 to 35, characterized in that the overlap within an annular channel of substantially constant rectangular cross-section is produced by a dividing wall ( 82 ) which is spirally inclined with respect to the reactor center axis. 37. Ring channel ( 18 , 20 ) according to one of claims 33 to 35, characterized in that the overlap within an annular channel of substantially constant rectangular cross-section is produced by a horizontal partition wall ( 82 ) arranged at half its height in conjunction with two vertical partition walls ( 94 , 96 ) adjoining it in a Z-shape. 38. Ring channel ( 18 , 20 ) according to one of claims 33 to 37, characterized in that a mixer ( 78 ) is formed within the overlap from an annular channel section covering the windows ( 34 ) there, with permeable upper and lower walls. 39. Ring channel ( 20 ) according to one of claims 33 to 38, characterized in that the relevant features are limited to the ring channel ( 20 ) on the heat transfer medium inlet side. 40. Ring channel ( 18 , 20 ) according to one of claims 1 to 39 with two ring channel sections ( 38 , 40 ; 84 , 86 ) which are essentially separate from one another and each connected to its own circulation pump ( 44 ), characterized in that the two ring channel sections are connected to a common heat exchanger ( 48 ). 41. Ring channel ( 18 , 20 ) according to claim 40 in conjunction with claim 33, characterized in that the connection of the two ring channel sections ( 84 , 86 ) with the heat exchanger ( 48 ) exists within the overlap. 42. Ring channel ( 18 , 20 ) according to claim 40 or 41, characterized in that the connection of the two ring channel sections ( 38 , 40 ; 84 , 86 ) with the heat exchanger ( 48 ) is established at least for the heat transfer medium returned from the heat exchanger via continuously controllable control means ( 98 ) which are able to divide the heat transfer medium flow to the desired extent. 43. Annular channel ( 18 , 20 ) according to claim 42, characterized in that the respective control means ( 98 ) consist of a multi-way valve, preferably in the form of a flap. 44. Annular channel ( 18 , 20 ) according to claim 42 or 43, characterized in that the respective control means ( 98 ) are automatically controlled by temperature sensors mounted at a suitable location. 45. Annular channel ( 164 ; 176 ) according to one of the preceding claims, characterized in that it covers at least one peripheral expansion joint ( 168 ) of the reactor shell ( 4 ). 46. Annular channel ( 164 ) according to claim 45, characterized in that the expansion joint ( 168 ) has a height of between 1 and 10 mm, preferably between 3 and 7 mm and most suitably of about 5 mm at about 20°C. 47. Annular channel ( 164 ) according to claim 45 or 46, characterized in that the expansion joint ( 168 ) is covered with a cover plate ( 170 ) anchored on one side only. 48. Annular channel ( 164 ; 176 ) according to one of claims 45 to 47, characterized in that the expansion joint ( 168 ) lies outside the windows ( 34 ) of the reactor shell ( 4 ) covered by the annular channel. 49. Annular channel ( 164 ) according to one of claims 45 to 47, characterized in that the expansion joint ( 168 ) extends through at least a part of the windows ( 34 ) of the reactor shell ( 4 ). 50. Annular channel ( 164 ) according to claim 45, characterized in that the expansion joint ( 168 ) itself forms a single, continuous window ( 34 ) for the passage of the heat transfer medium. 51. Annular channel ( 164 ) according to claim 50, characterized in that the expansion joint ( 168 ) varies in height in the sense of a heat transfer medium passage distributed in the desired manner over the reactor circumference. 52. Annular channel ( 164 ; 176 ) according to one of claims 45 to 49, characterized in that the expansion joint ( 168 ) is arranged at a location where it influences the intended heat transfer medium flow as little as possible. 53. Annular channel ( 164 ; 176 ) according to one of claims 45 to 52, characterized in that the expansion joint ( 168 ) consists of a gap between the reactor shell ( 4 ) and a tube sheet ( 10 , 12 ) or separating plate ( 178 ) which overlaps the latter to the outside. 54. Annular channel ( 176 ) according to claim 53 with an expansion joint ( 168 ) as a gap between the reactor shell ( 4 ) and the separating plate ( 178 ), characterized in that the separating plate passes through the gap with play and is anchored in the outer wall ( 180 ) of the annular channel. 55. Annular channel ( 176 ) according to claim 54, characterized in that it is divided by the separating plate ( 178 ) into two separate sections ( 172 , 174 ) which adjoin one another along their entire length and have their own windows ( 34 ), one for each of the two reactor sections separated from one another by the separating plate. 56. Ring channel ( 176 ) according to claim 54 or 55, characterized in that the separating plate ( 178 ) has a reduced wall thickness in the region of the ring channel. 57. Annular channel ( 76 ) according to one of claims 53 to 56, characterized in that the tube sheet ( 10 , 12 ) or the separating plate ( 178 ) is thermally insulated into the annular channel. 58. Annular channel ( 176 ) according to one of the preceding claims, characterized in that it has at least one gas extraction element ( 184 ) for degassing the heat transfer medium. 59. Ring channel ( 176 ) according to claim 58, characterized in that several gas extraction elements ( 184 ) of the ring channel, optionally together with those in the reactor interior and, if necessary, via throttle elements, are connected to a common gas discharge line ( 186 ). 60. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to one of the preceding claims with the exception of claims 27, 28 and 30, characterized in that it contains struts ( 190 ) running through it for supporting the reactor ( 2 ) on supports ( 194 ) lying radially outside the reactor shell ( 4 ) in plan view. 61. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to claim 60, characterized in that the struts ( 190 ) consist essentially of metal sheets following the curvature of the annular channel. 62. Annular channel ( 18 , 20 ; 30 ; 72 ; 80 ; 102 ; 108 ; 130 ; 142 ; 150 ; 160 ; 176 ) according to claim 60 or 61, characterized in that the struts ( 190 ) are aerodynamically profiled with respect to the heat transfer medium flow passing through the annular channel.