DE102010014643A1 - Tube bundle reactor, useful for catalytic gas phase reactions, comprises bundle of vertically arranged reaction tubes, a reactor shell, deflecting plate, reverse opening, bypass openings arranged in deflecting plate and adjusting device - Google Patents

Abstract

Tube bundle reactor comprises: a bundle of vertically arranged reaction tubes, an upper and a lower tube sheet tightly connected to the upper and lower ends of the reaction tubes and lead through the reaction tubes in gas supply- and gas discharge devices; and a reactor shell enclosing tube bundle; at least one deflecting plate; a reverse opening (5) for releasing heat transfer medium, so that transfer medium flows in meander-form through tube bundle in the longitudinal direction, and bypass openings arranged in at least one deflecting plate in its piping region; and an adjusting device. Tube bundle reactor comprises: a bundle of vertically arranged reaction tubes, an upper and a lower tube sheet tightly connected to the upper and lower ends of the reaction tubes and lead through the reaction tubes in gas supply- and gas discharge devices; and a reactor shell enclosing the tube bundle, which is connected pressure tightly to the tube sheets, and together with the tube sheets, the reactor shell forms a pressure chamber (18), in which the reaction tubes are washed in the operation of a heat transfer medium (8); at least one deflecting plate, which extends across through the tube bundle and imposes a cross-flow to the heat transfer medium; a reverse opening (5) for releasing the heat transfer medium, so that the transfer medium flows in meander-form through the tube bundle in the longitudinal direction, and bypass openings arranged in at least one deflecting plate in its piping region; and an adjusting device (4) for adjusting the flow resistance in the reverse opening or at least one part of the bypass openings, where the adjusting device of a first position, in which the flow resistance allows a meander-form reverse of the flow direction of a partial flow quantity of heat transfer medium and is movable in at least one second position, where the flow resistance is increased, such that the partial flow quantity is reduced, or at least one tube-free region is formed in the pressure chamber, and at least one steam outlet opening is formed in a first deflecting plate in the tube-free region outside the reverse opening. The second deflecting plate in the tube-free region outside the reversal opening is substantially closed, and the adjusting device is formed for each steam outlet opening. The adjusting device is movable between a closed position in which it closes the steam outlet opening, and an open position in which it releases the steam outlet opening. An independent claim is also included for tempering the tube bundle reactor by the tempering gases, comprising (a) providing a tempering device, (b) shifting the tempering device into the heat transfer circuit, (c) filling the heat transfer circuit with the tempering gas (132) with a predetermined pressure, and (d) circulating the tempering gas.

Description

The invention relates to a tube reactor for catalytic gas phase reactions, comprising a bundle of vertically arranged reaction tubes, an upper and a lower tube plate, which are sealed to the upper and lower ends of the reaction tubes and through which open the reaction tubes in gas supply and Gasableitungseinrichtungen , A reactor shell, which encloses the tube bundle and is tightly connected to the tube sheets to form a pressure space with them, in which the reaction tubes are lapped in operation by a heat transfer medium, and with at least one baffle, which extends across the tube bundle and the Heat transfer forces a transverse flow and leaves a reversal opening for the heat carrier so that the heat transfer medium flows through the tube bundle in its longitudinal direction.

In such tube bundle reactors, the heat transfer medium, for example molten salt, is guided meander-shaped by the deflection plates in the forced circulation through the tube bundle in order to effect a transverse flow of the reaction tubes. The cross-flow causes a high heat transfer, which ensures sufficient heat dissipation at high reaction temperatures. Crucial for the production quality and yield is a uniform over the reactor cross-section temperature distribution, d. H. a as uniform as possible over the reactor cross section heat transfer. A significant influencing factor for the heat transfer is the flow velocity of the heat carrier. However, this varies in the case of conventional, cylindrical tube bundle reactors in the radial direction, since the flow cross-section decreases radially inwardly and therefore the flow velocity increases.

To equalize the flow velocity of the heat carrier was therefore in WO 2004/052524 A1 proposed for tube bundle reactors with annular and disc-shaped baffles, to arrange in the baffles between the reaction tubes bypass openings whose total opening cross section increases radially inwardly and flow through the subsets of the heat carrier, so that accordingly reduces its flow velocity.

The baffles may also be arranged alternately opposite, such as. In WO 2004/052776 A1 described and illustrated. There is also described and illustrated that some leakage through the through holes for the reaction tubes in the baffles occurs because due to unavoidable pipe tolerances and bore tolerances gap between tube outer wall and bore wall can not be avoided. However, these annular gaps should be sufficiently low to ensure a secure support of the reaction tubes in the holes. In addition, they vary in size relative to the tolerances relatively strong. A safe outflow of predetermined subsets of the heat carrier is therefore not given by these annular gaps.

In shell and tube reactors with forced circulation thus a considerable effort to achieve the most uniform temperature distribution is necessary. In addition, a circulation device for the heat transfer medium is required, which increases the manufacturing costs and brings additional effort for maintenance and repair.

For controlling the amount of heat transfer medium, which flows through a tube bundle, is for a tube bundle reactor with forced circulation in the US 5615738 proposed, within the reactor outside of the tube bundle on one side in all there extending baffles form a closable opening, which allows in the open state, a portion of the heat transfer stream to flow parallel to the reaction tubes at this past the heat transfer to the heat transfer outlet, ie outside the tube bundle to form a continuous from the heat transfer to the heat transfer outlet inner bypass. Furthermore, it is proposed to completely close a reversal opening ( 12 and 13 ) to completely stop the heat carrier flow through the tube bundle reactor and to direct the entire heat transfer stream via an external bypass.

In order to avoid the difficulties with respect to the homogenization of the temperature distribution in forced circulation, is therefore working in a reaction temperature range of about 150 ° C to about 280 ° C often with boiling water cooling, in which the heat carrier evaporates and as the heat transfer evaporates, liquid heat carrier is supplied. A circulation of the heat carrier adjusts itself here due to the density difference in the transition from the liquid phase to the vapor phase; this is called natural circulation. The heat transfer medium flows predominantly axially in the longitudinal direction of the reaction tubes. A good heat transfer takes place here solely by the boiling process and requires no directional flow.

For boiling water tube bundle reactors, the uniform distribution of a homogeneous water-vapor mixture in the pressure chamber is essential for a uniform temperature distribution. No or only slightly flowed through areas should be avoided to prevent local drying out and overheating of the reaction tubes. This is z. B. achieved by special holding disks or holding grid. These fulfill two tasks: on the one hand, they support the reaction tubes by spring elements and thus prevent flow-induced vibrations. On the other hand, they have flow guidance devices for generating turbulence in order to increase the heat transfer, to mix the heat transfer medium and to distribute it evenly over the flow cross section. As an example, here is the US 5303276 called.

When holding slices strikes EP 0382098 A2 to subdivide the retaining washers into different circular rings and to form the annular gaps between the reaction tubes and their through holes of circular ring to circular ring of different sizes. In this case, two mutually aligned circular rings of two adjacent retaining washers have different sized annular gaps, so that a certain cross-flow component is imposed on the axially flowing heat transfer medium to improve the heat transfer when it flows between non-aligned circular rings of adjacent retaining washers.

In the US 3147743 a steam generator with integrated superheater is described. This has perforated holding plates in the evaporation area. In the overheating part of the baffles are annular and disc-shaped, in order to give the fluid to be heated a flow direction transverse to the tubes and thereby to improve the heat transfer.

Depending on the expected range of reaction temperatures either a shell-and-tube reactor with forced circulation operation or a tube bundle reactor with boiling water operation is provided. If some of the envisaged reactions in the temperature range for forced circulation operation and other reactions in a temperature range for boiling water operation, two appropriately designed tube bundle reactors are required.

The object of the invention is to propose a tube bundle reactor with which both a forced circulation operation and a boiling water operation can be carried out.

According to the invention this object is achieved by a tube bundle reactor with the features according to claims 1, 3 or 6.

Advantageous embodiments are specified in the respective subclaims.

According to claim 1, the object is in a tube bundle reactor of the type mentioned, which has bypass openings, which are arranged in the at least one baffle in the burred area, solved by an adjusting device for adjusting the flow resistance in the reversal opening, wherein the adjusting device from a first position in which the flow resistance allows a meandering reversal of the flow direction of a predetermined partial flow of the heat carrier, in at least one second position is movable in which the flow resistance is increased so far that this amount of partial flow is reduced.

Under bypass openings in this case understood the annular gaps between the reaction tubes and their passage holes through the baffle and additional through holes between the reaction tube through holes.

By these measures according to the invention, the amount of partial flow of the heat carrier, which reaches the reversal opening as a cross-flow and then flows through them, d. H. which has not previously flowed through the bypass openings set. In other words, it is the ratio of the cross-flow component, which flows through the tube bundle meandering, adjusted to Axialstromanteil, which flows axially through the tube bundle through the bypass openings. A changeover of the operation between forced circulation, in which the cross-flow predominates on boiling water operation with natural circulation and predominantly Axialstromanteil is readily possible in this way.

In an advantageous embodiment of the invention, the adjusting device is adapted to close the reversal opening in one position. As a result, a meandering order to reverse a partial flow amount of the heat carrier in the reversal opening completely prevented and thus reduces the cross-flow component to zero. The tube bundle reactor is then operated as usual boiling water reactors exclusively with axial flow of the heat carrier.

According to claim 3, the object is in a tube bundle reactor of the type mentioned, which has at least two baffles which extend transversely through the tube bundle, are arranged one above the other in the longitudinal direction of the reaction tubes, impose a cross flow on the heat carrier and each release a reversal opening for the heat carrier, so that the heat transfer medium flows through the tube bundle in the longitudinal direction, achieved by forming at least one tube-free region in the pressure chamber, at least one vapor discharge opening is formed in at least one first of the baffles in the tube-free region outside the reversal opening and the second guide plate in the tube-free region outside Reverse opening is substantially closed, and that an adjusting device is formed for each steam outlet opening, wherein the adjusting device between a closed position in which it closes the steam outlet opening , and an open position in which it releases the steam outlet, is movable.

The term "substantially closed" is intended to indicate that leaks may occur, e.g. B. by closing devices due to tolerances, mounting supports, brackets, anti-rotation, supports or through inspection openings or the like.

The term "tube-free area" is understood, on the one hand, to mean any area outside the tube bundle in the pressure space, such as a tube-free outer ring between tube bundle and reactor jacket and a tube-free center, but also any interruption of the regular tube arrangement within the tube bundle, d. H. released halftone dots.

These measures according to the invention enable a boiling water operation with natural circulation in a meandering guide of the heat carrier through the tube bundle. This is based on the finding that in boiling water operation with cross-flow guidance in the cross-flow increased separation of water and steam takes place and collects a vapor cushion under the baffle. The heat transfer from the reaction tubes to the steam is significantly worse than that to the water, so that the reaction tubes in the region of the steam cushion are cooled worse. In any case, this results in an uneven temperature distribution, possibly even inadequate cooling. The inventive design of a steam discharge opening in this area, a derivative of the steam and thus a reduction of the steam cushion is achieved as far as possible. If the operation of boiling water cooling - d. H. Evaporative cooling - switched to a non-evaporating cooling, so can be closed with the adjustment the steam outlet and the axial flow are prevented therethrough, which then there are the same flow conditions as in a conventional shell-and-tube reactor for forced circulation. It is important that at least one baffle is closed in the tube-free areas in which other baffles have steam discharge openings to avoid the emergence of a bypass over the entire height of the pressure chamber with open steam discharge openings. By such a bypass, the heat transfer medium would shoot past the tube bundle in the manner of a short circuit. This would be detrimental to the cooling water content in the tube bundle.

In a favorable development of the invention, the at least one steam outlet opening of the first deflecting plate is arranged close to the reversing opening of the second deflecting plate, and the adjusting device is arranged to close the reversing opening in an open position. In this way, the number of adjusting devices in the pressure chamber can be significantly reduced.

Preferably, vapor discharge openings are arranged in the form of a row or a ring or on a compact surface. A sufficient derivation of possibly significant resulting in cross-flow amounts of steam is ensured.

According to claim 6, the object is in a tube bundle reactor of the type mentioned, which has bypass openings, which are arranged in the at least one baffle in the burred area, solved by an adjusting device for adjusting the flow resistance in at least part of the bypass openings.

By this measure, the cross sections of the bypass openings can be chosen so large that they meet the requirements of a boiling water operation when the flow resistance of the bypass openings is not adjusted. If the tube bundle reactor is to be operated with forced circulation, the flow resistance of the bypass openings can be adjusted or reduced by means of the adjustment device to the size which is suitable for forced circulation operation.

In a preferred embodiment of the invention, the adjusting device is adapted to close in one position the bypass openings in order to produce a maximum flow resistance.

Preferably, the tube bundle reactors according to the invention have an actuating device with which the respective adjusting device can be moved from one position to another position. An actuator allows easy access to the adjustment.

In this case, the actuating device is advantageously connected to a plurality of adjusting devices and actuates these simultaneously. As a result, on the one hand the time required for adjusting a plurality of adjusting devices is considerably shortened, and on the other hand, the space requirement for the actuating devices is significantly reduced.

Preferably, the actuator is disposed within the pressure chamber. This eliminates passages for the actuators, including the corresponding seals and the risk of leaks.

In this case, the pressure chamber preferably has a closable connecting piece, through which the actuating device can be actuated from outside the pressure chamber. Easy access to the actuator is guaranteed.

In a favorable embodiment of the invention, the actuating device and is / are the associated) adjusting device (s) through the neck through mounted and disassembled. Maintenance and repair work can be carried out in this way without much effort.

In a preferred embodiment of the invention, the actuating device is operable by means of a drive element having a housing which is tightly connected to the pressure chamber and has a passage opening which is aligned with an access opening to the pressure chamber and from which protrudes a movable member from the housing is connected to the actuating device. By these measures, a machine movement of the adjustment is possible. In this way, devices can be moved, which have a high weight, such as. B. an actuator, which is connected to a plurality of adjusting devices.

The drive medium of the drive element is preferably the same medium, which is used as a heat carrier. In this case, the passage opening of the housing need not be completely sealed against the access opening to the pressure chamber, as emerging from the housing drive medium can easily enter the pressure chamber, since it is the same medium as the heat carrier.

Preferred as a drive element is a lifting cylinder. This is a simple and inexpensive way to design the drive element constructive.

In a favorable embodiment of the invention, the features of at least two of the tube bundle reactors according to claims 1, 3 or 6 can be combined. The features complement each other and improve by their interaction depending on the position of the adjusting the forced circulation operation or the boiling water operation.

Preferably, a tube bundle reactor according to the invention has a steam drum which is arranged above the pressure chamber and is in flow connection via at least one riser and only one downpipe to the pressure space, the downcomer having a shut-off device and at least one closable branch before and after the shut-off device. With these measures, an external circulation device for the heat transfer medium can be switched into the heat transfer medium circulation in a simple manner for the forced circulation operation by connecting the branches to the inlet or outlet of the circulation device.

In this case, the downpipe preferably extends outside and along the pressure space. As a result, the accessibility of the branches is further improved.

In a further preferred embodiment of the invention, the steam drum is mounted on the downpipe. Separate support devices for the steam drum are no longer necessary in this case.

It is particularly advantageous if such a tube bundle reactor, in which the steam drum communicates with the pressure space via only one downpipe, is provided with supply pipes and discharge pipes for the heat transfer medium, which extend in the axial direction through the tube sheets, as this in DE 10 2007 024 934 A1 , z. B. 8th , is shown. By eliminating the loop, a particularly close arrangement of the downpipe on the reactor jacket and thus a direct support of the downpipe on the outside of the reactor shell or on the frame is possible.

In a preferred embodiment of the invention, the tube bundle reactor has a tempering device for its tempering by means of a tempering gas, wherein the temperature control device can be brought into fluid communication with a heat carrier inlet and a heat carrier outlet of the pressure chamber and the temperature gas flows through the temperature control device and the pressure chamber, with a gas supply, a heating device for the tempering gas, a conveyor for the temperature control, wherein the gas supply is a compressed gas supply.

With the help of such a tempering according to the invention, the tube bundle reactors described above, the pressure chamber is part of a heat carrier, tempered by a Temperiergases by the temperature control is switched into the heat carrier circuit, the heat transfer medium is filled with the tempering gas with a predetermined pressure and the temperature control is circulated.

In the temperature range of about 250 to 650 ° C salt melts are often used for heat dissipation. These heat carriers have a very low vapor pressure and are operated without pressure during operation. For underlying temperatures up to about 400 ° C come organic heat transfer such. B. heat transfer oils used. Tube bundle reactors for this type of heat transfer are z. B. from the DE 2 207 166 A1 or the EP 1 569 745 A1 known.

A particular problem may arise when it is necessary during commissioning or when decommissioning a tube bundle reactor and also during operation to condition the catalyst. By "conditioning" is meant to provide the catalyst with certain properties.

Thus, it may be necessary, the catalyst before or at startup of the tube bundle reactor of an inactive state, the z. B. has resulted in contact with atmospheric oxygen during transport and filling in the catalyst space to bring into an active state for production. Conversely, it may be necessary during or after the decommissioning of a tube bundle reactor to deactivate the still active catalyst for safe replacement and removal.

Furthermore, during various chemical reactions, the activity of the catalyst gradually decreases during operation, and the catalyst is likewise deactivated here, although undesirably. This can have different causes. The catalyst may, for. B. are oxidized over time or the catalyst surface is coated with carbon black or other impurities. To ensure economic production, the activity of the catalyst must be restored. A complete replacement of the catalyst is complicated and expensive, so that, if possible, a conditioning of the catalyst, which is referred to in this case as regeneration, preferred in situ. The regeneration intervals depend on the respective processes.

The conditioning takes place in that a conditioning gas is passed through the catalyst bed for a relatively short period of time of the order of several hours to a few days. This has a composition, a temperature and a pressure, which are adapted to the respective process. There are oxidation reactions or reduction reactions. Each influencing variable has corresponding constructive measures. The composition and the pressure can be changed well by switching devices in front of the reactor usually well.

The essential problem of any conditioning process is the maintenance of a certain temperature at each point of the catalyst bed. For this purpose, it is not sufficient to temper only the conditioning gas in front of the reactor, since this already assumes the temperature prevailing in the reactor after a short inlet section. In addition, the conditioning process is usually either endothermic or exothermic. A temperature of the catalyst bed from the heat carrier side is therefore essential. The difficulty lies in the fact that the respective heat transfer system for economic reasons is usually very specifically adapted to the particular production process and the required conditioning temperature is considerably higher than the reaction temperature in the production process and thus not adjusted can. For the duration of the conditioning, therefore, the production or operational heat transfer medium is replaced by one which can maintain the conditioning temperature.

In chemical production processes with reaction temperatures below 300 ° C, the z. B. can be operated in boiling water, salt melts are used as a heat carrier for the entire operation only because of short-term regeneration processes with temperatures above 400 ° C salt. However, the use of molten salt as a heat carrier is more expensive than a direct boiling water cooling.

A simpler and cheaper method is from the DE 38 19 357 A1 known. The method relates to the regeneration of a granular catalyst in the reaction tubes of a tube bundle reactor, which is designed for a pressure of 20 to 150 bar, and the reaction tubes are cooled by a cooling liquid flowing through the jacket space. In this regeneration process, the cooling liquid is first removed from the shell space, then the catalyst is heated in direct contact with hot regeneration gas to temperatures that are 100 to 400 ° C above those in production conditions. Subsequently, a gaseous or vaporous heating medium is introduced into the shell space, whereby the temperature difference between the outside of the reaction tubes and the inside of the reactor shell is kept at most 100 ° C. Prior to regeneration, the catalyst may be purged with hot nitrogen. As a heat carrier can, for. As hot nitrogen or superheated steam can be used. The changes of the operating conditions are brought about by means of valves. Information on further details of the heat transfer system used in the regeneration process are not made. In this type of tempering, however, the temperature of the gaseous or vaporous heating medium changes considerably on its way from the inlet into the shell space to the outlet, so that in the longitudinal direction of the reaction tubes, the temperature distribution is highly uneven, which is disadvantageous for a uniform regeneration of the catalyst ,

The WO2009 / 118372 A1 describes a process for in situ regeneration of a cobalt and titanium-containing catalyst deactivated in a Fischer-Tropsch process in a fixed bed by an oxidation step at a temperature between 580 ° C and 670 ° C and a subsequent reduction step with an at least partially hydrogen-containing catalyst Gas. The catalyst is preferably located in reaction tubes of a tube bundle reactor, which are cooled on the shell side during the regeneration of water and / or steam. In stationary operation, the Fischer-Tropsch process is carried out at temperatures between 100 and 600 ° C and pressures between 5-150 bar. Further information on the heat transfer system will not be made.

With the proposed tempering and the proposed method for tempering, in particular for conditioning, a tube bundle reactor, a more uniform temperature distribution and a better heat dissipation or supply can be achieved and at the same time the technical and the cost can be further reduced.

The measures according to the invention significantly increase the tempering performance and thereby significantly reduce the space required for the tempering device. Because the gas supply is a pressurized gas supply, the volume flow and thus the flow velocity are lower for the same mass flow rate. The pressure loss thus decreases approximately linearly with increasing pressure at the same mass flow rate.

Conversely, it is possible to circulate at a given flow cross sections of the reactor system, a higher mass flow rate at a constant pressure loss. A higher mass flow rate means a higher heat absorption capacity of the tempering gas and a higher heat transfer at the reaction tube walls. In this case, the temperature of the compressed gas in the tube bundle reactor increases only slightly, so that the temperature distribution is extremely uniform both over the cross section of the tube bundle reactor and in the longitudinal direction of the reaction tubes. Thus, the temperature control can be significantly increased without having to accept a disproportionately strong increase in the drive power of the circulation fan in purchasing. As a result, space and weight can be saved in the drive motor and its electrical supply facilities. At the same time, the flow cross sections of the apparatuses and inner pipes of the tempering device can be made smaller, thereby reducing their space.

Preferably, the pressurized gas supply to a compressor. The compressed gas can thus be generated in a simple and cost-effective manner.

In a favorable embodiment of the invention, the compressed gas has a pressure in the range of 3 to 100 bar, preferably in the range of 5 to 50 bar and particularly preferably in the range of 10 to 30 bar. In these pressure ranges, in particular in the range of 10 to 30 bar, a considerable increase in the temperature control is already achieved with only a relatively small increase in the drive power of the circulation fan.

In an advantageous embodiment of the invention, the temperature control device is mounted on a transportable frame. This is possible due to the very compact design of the tempering device due to the reduced installation space. This can thus be easily transported to different reactor systems. The use of a mobile temperature control device successively on several reactor systems reduces the relative investment costs per reactor system. The outer dimensions of such a transportable frame preferably correspond to the footprint of commercial cargo containers, for example, the width is 2.438 m (8 feet) at a length of 6,058 m (20 feet) or 12,192 m (40 feet).

Preferably, the temperature control device has two connecting lines for connection to the Wämreträgereinlass or the heat transfer outlet of the heat transfer chamber, of which at least one has an elastic intermediate piece. Due to these flexible connections complex adjustments to the connections of the reactor system to compensate for positional tolerances are not required. In particular, in a mobile version of the temperature control, a connection to different reactor systems is readily possible by these measures.

In this case, the elastic intermediate pieces adjustable tension relief for receiving internal pressure forces. As a result, the elastic intermediate pieces can absorb internal pressure forces in a simple manner, without burdening the subsequent pipeline parts.

Preferably, the temperature control gas contains air, nitrogen, carbon dioxide, water vapor or a mixture thereof. These gases are readily available and therefore relatively inexpensive.

In a favorable embodiment of the invention, the tempering device has a cooling device for cooling the tempering gas, which is set up to inject water directly into the tempering gas cycle. As a result, a simple and rapid adjustment of the desired temperature of the tempering gas is possible.

The tempering device preferably has regulating devices for regulating the temperature and the pressure of the tempering gas. Temperature and pressure of the tempering gas can be kept so reliable.

In an advantageous embodiment of the method according to the invention for conditioning a catalyst bed in a tube bundle reactor, the heat transfer medium is flowed through in the production phase of a liquid or teilverdampfenden heat transfer during the circulation of the tempering the temperature and optionally the pressure of the tempering gas to the starting temperature of the conditioning increases and passing the conditioning gas through the catalyst bed. The conditioning of a catalyst bed also includes the regeneration of a used catalyst bed. With these measures, in situ conditioning of a catalyst bed in a tube bundle reactor is possible in a simple manner. Because of the pressure gas, the temperature distribution of the tempering gas is extremely uniform both transversely to the reaction tubes and in their longitudinal direction, so that the conditioning process also proceeds uniformly throughout the catalyst bed, thus ensuring a uniform quality of the catalyst bed. To support the operation, in step d) of claim 29, a heating gas before the conditioning gas are passed through the catalyst bed.

In a favorable development of the invention, the tempering device is mounted on a transportable frame and is transported to the tube reactor for tempering and transported away again after completion of the tempering process. As a result, the cost of a stationary temperature control are avoided, which would otherwise be provided in each tube bundle reactor. The relative investment costs of the tempering device per tube bundle reactor are significantly reduced in this way.

The invention will be explained in more detail below with reference to the drawings by way of example. Show it:

1 a vertical section through a first embodiment of a tube bundle reactor according to the invention, with adjustable reversing opening and adjustable steam outlet opening;

2 in an enlarged view a section of a baffle 1 ;

3 a partial vertical section through a second embodiment of a tube bundle reactor according to the invention, with adjustable reversing opening, adjustable steam outlet opening and within the pressure chamber arranged actuating devices;

4a a partial cross section through a baffle of a third embodiment of a tube bundle reactor according to the invention, with adjustable bypass openings, wherein the adjusting device is axially movable;

4b one of the 4a similar partial cross-section, wherein the adjusting device is laterally movable;

5a a partial cross-section through a fourth embodiment of a tube bundle reactor according to the invention, with adjustable reversing opening, wherein the adjusting device is designed as a cylindrical rotary valve in the tube-free inner region of an annular tube bundle;

5b a horizontal section through the adjustment of 5a along line Vb-Vb;

6 a vertical section through a fifth embodiment of a tube bundle reactor according to the invention, with adjustable by lifting cylinder reversal openings and steam outlet openings, wherein the working medium of the lifting cylinder is the heat transfer medium; and

7 in a schematic representation of a tube bundle reactor according to the invention with a steam drum for the boiling water operation, wherein the steam drum is connected via only one downpipe to the pressure chamber and the downcomer has a shut-off device and branches.

8th a flow diagram for a first embodiment of a temperature control, which is connected in the heat transfer circuit of a tube bundle reactor according to the invention;

9a a schematic representation of a side view of a second embodiment of a temperature control, which is connected in the heat transfer circuit of a tube bundle reactor according to the invention; and

9b in a schematic representation of a plan view of the second embodiment 9a ,

• a) nur Verstellvorrichtungen 4 für Umkehröffnungen 5 oder
• b) nur Dampfablassöffnungen 2 mit zugehörigen Verstellvorrichtungen 3 aufweisen.

Although the in 1 . 3 and 6 illustrated embodiments of inventive tube bundle reactors 1 each with both steam outlet openings 2 and adjusting devices 3 for these as well as adjusting devices 4 for reverse openings 5 have, it is expressly understood that the invention is not limited to this combination, but according to the invention also generic tube bundle reactors for operation with forced circulation and natural circulation are suitable if they

• a) only adjusting devices 4 for reverse openings 5 or
• b) only steam discharge openings 2 with associated adjusting devices 3 exhibit.

It should also be noted that according to the invention generic tube bundle reactors 1 be suitable for operation with forced circulation and with natural circulation, if they c) only adjusting devices 6 for bypass openings 7 have, as z. Tie 4a and 4b are shown
however, the scope of the invention also includes the combination of measure c) with one or both of measures a) and b).

1 schematically shows a single-tone and the heat transfer medium 8th in the case shown in the forced circulation radially flowed tube bundle reactor 1 with adjustable flow resistance in the area of baffles 26a + b, 27 so that the tube bundle reactor 1 Also suitable for exothermic reactions involving reaction tubes 9 by a partially evaporating heat transfer medium 8th be cooled on the shell side in natural circulation. Not shown are the individual components of the heat transfer system, such. B. Umwälzeinrichtung, cooling device, steam drum, heater.

The tube bundle reactor 1 has a plurality of vertically extending reaction tubes 9 on that in an annular tube bundle 10 with an outer tube circle 11 and an inner tube circle 12 arranged and by a cylindrical reactor jacket 13 are enclosed. The tube bundle 10 has a tube-free center 14 on. Between tube bundles 10 and reactor jacket 13 is a tube-free outer ring 15 educated. The ends of the reaction tubes 14 are sealing in an upper tube sheet 16 and in a lower tube sheet 17 attached. The tube sheets 16 . 17 are at their outside area with the reactor shell 13 tightly connected. tube sheets 16 . 17 and reactor jacket 13 together form a pressure room 18 for the heat carrier. The upper tube sheet 16 is through an upper flange 19 with an upper gas inlet hood 20 connected, which has a gas inlet nozzle 21 and in which the upper ends of the reaction tubes 9 lead. The bottom tube sheet 17 is through a lower flange 22 with a lower gas outlet hood 23 connected, which has a gas outlet 24 and in which the lower ends of the reaction tubes 9 lead. The reaction gas 25 enters via the gas inlet nozzle 21 in the gas inlet hood 20 one, there is on the upper tube sheet 16 distributed, flows through the reaction tubes 9 and through the gas outlet 24 the gas outlet hood 23 from the reactor 1 out again.

The tube bundle 10 is through two annular baffles 26 and a disc-shaped baffle 27 in four tube bundle sections 28 . 29 . 30 . 31 subdivided in the following from bottom to top as the first 28 second 29 , third 30 and fourth or last 31 be designated. Preferably, the baffles 26a + b, 27 to the ends of the tube bundle 10 zoom in, ie the pipes 9 on the inner tube circle 12 Be sure on the inner diameter of the annular baffles 26a + b supports and the pipes 9 on the outer pipe circuit 11 Be sure on the outer diameter of the disc-shaped baffle 27 supported.

At the height of the first tube bundle section 28 runs on the outside of the reactor shell 13 in the circumferential direction, a lower annular channel 32 who has an entrance neck 33 for the heat carrier 8th has and a variety of suitably shaped jacket window 34 , which are distributed over the entire reactor circumference, with the pressure chamber 18 is in flow communication. The heat carrier 8th is in the lower ring channel 32 distributed over the circumference and passes through the jacket window 34 evenly distributed over the reactor circumference in the pressure chamber 18 one.

At the height of the last tube bundle section 31 runs on the outside of the reactor shell 13 in the circumferential direction an upper annular channel 35 , who has an outlet nozzle 36 for the heat carrier 8th and how the lower ring channel 32 over a variety of suitably designed, over the entire reactor circumference distributed jacket window 37 with the pressure room 18 is in flow communication. The heat carrier 8th comes out of the pressure room 18 through the jacket window 37 in the upper ring channel 35 in and out of this through the outlet nozzle 36 out.

The central opening 38 in each annular baffle 26a + b and the opening 39 between the outer edge disc-shaped baffles 27 and the reactor jacket 13 will also be referred to as reversal opening 5 referred to as there in forced circulation, the flow direction of the heat carrier 8th meandering reversed, as will be explained in more detail below.

In the tube-free center 14 is a first adjustment 4 for adjusting the flow resistance in the reversing opening 5 of the lower annular baffle 26a educated. The first adjusting device 4 is formed in the illustrated embodiment as a lid, which by means of a first actuating rod 40 vertically from a position in which the lid 4 near the bottom of the adjacent baffle 27 is and the flow resistance of the reversal opening 5 the lower baffle 26a not adjusted, is movable to a position in which the lid 4 on the reverse opening 5 rests and essentially closes them. The term "substantially" is intended to mean that leaks z. B. are possible due to bumps.

The first operating rod 40 passes through the middle disk-shaped deflection plate 27 and the upper tube sheet 16 , against which it is sealed, and protrudes into the gas inlet hood 20 into it.

In the tube-free outer ring 15 are in the upper annular baffle 26b openings 2 formed, which are hereinafter referred to as steam discharge openings. In boiling water mode can through the steam outlet openings 2 Passing through steam, as will be explained in more detail below.

Steam discharge openings may also be in tube-free areas within the tube bundle 10 be arranged. In this case, the shape of the tube-free region or the arrangement of the steam outlet opening 2 arbitrarily, z. B. alley, compact or annular.

With second adjusting devices 3 can the steam outlet openings 2 be substantially closed to force a meandering cross flow in forced circulation there. These second adjusting devices 3 are also formed in the illustrated embodiment as a lid and in each case by means of a second actuating rod 41 between the closed position, in which the lid 3 on the steam outlet 2 rests, and an open position movable, in which the lid 3 the steam outlet opening 2 releases.

The second actuating rods 41 go through the upper tube sheet 16 and the gas inlet hood 20 , against which they are respectively sealed, and protrude out of this outward, so they from outside the tube bundle reactor 1 are operable.

The confirmation bars 40 . 41 are operated either purely mechanically directly or via a gearbox manually or with mechanical help.

The adjusting devices 3 . 4 However, they are usually operated only at longer intervals to change the operating conditions. It may therefore also be useful to the actuators 40 . 41 to be arranged completely inside the reactor.

In all baffles 26a + b, 27 are in the drilled area between the reaction tubes 9 Main Bypassöffungen 42 formed by the subsets of the heat carrier 8th flow through.

Furthermore, flow through subsets of the heat carrier 8th also ring gaps 43 ( 2 . 4a . 4b ) between the outer diameters of the reaction tubes 9 and the pipe bores 44 in which the reaction tubes 9 the baffles 26a + b, 27 run through. This ring gap 43 are unavoidable due to the tolerances and can only be sealed with considerable effort. In the context of this application, the term "bypass openings" 7 also such annular gaps 43 Understood; they are referred to as "by-pass ports."

In the case of a first operating state with a guided in forced circulation heat transfer 8th in the purely liquid state or in the purely gaseous state, the first adjusting device 4 in the position in which they have the flow resistance in the reverse opening 5 not adjusted, ie the reversal opening 5 releases, and close the second adjustment 3 the steam outlet openings 2 , The heat carrier 8th flows in the first tube bundle section 28 radially inward. A subset of the heat carrier 8th flows over the main bypass openings 42 in the annular baffle 26a in the adjacent tube bundle section 29 , Thus, the flow rate of the radially inwardly flowing heat carrier 8th is not too large due to the constantly decreasing flow cross section. Preferably, the main bypass openings 42 in the baffles 26a + b, the heat carrier 8th radially inward, radially larger from outside to inside.

In 2 becomes a section of a baffle 26a + b, 27 shown with the passage of the reaction tubes 9 through the pipe bores 44 in the baffle 26a + b, 27 , The pipe bores 44 have - as mentioned above - always a constructive gap 43 to the reaction tubes 9 , This is due to the manufacturing tolerances both in the outer diameter of the reaction tubes 9 as well as the bore diameters. One for all pipes 9 well-defined gap 43 with a cross-section for the determination of certain partial flows from one tube bundle section to another can not be determined due to the tolerances. In addition, the goal is usually the gap 43 make small, so that the reaction tubes 9 to avoid flow-induced vibrations safely from the baffle 26a + b, 27 being held.

One solution to this problem is provided by the main bypass openings 42 between the pipe bores 44 , These can be easily done in the course of making the pipe bores 44 are manufactured and are well controlled in their size. The flow resistance of such main bypass openings 42 is also very predictable and reproducible.

After the heat transfer 8th the first tube bundle section 28 on the inner tube circle 12 he has left in the reverse opening 5 of the annular baffle 26a initially axially upwards and then in the second tube bundle section 29 guided from the inside to the outside. Here, too, flow subsets of the heat carrier 8th via main bypass openings 42 in the disk-shaped deflecting plate 27 in the adjacent, third tube bundle section 30 , However, this is not necessary with forced circulation, but with natural circulation of gaseous and liquid heat transfer medium 8th can flow axially, as will be explained in more detail below for the second operating state. The main bypass openings 42 in the disk-shaped deflecting plate 27 have a minimum size to avoid clogging and are preferably the same large. After leaving the second tube bundle section 29 on the outer pipe circuit 11 becomes the heat carrier 8th in the reversal opening 5 in the tube-free area 15 between the outer diameter of the disc-shaped deflecting plate 27 and the reactor inner wall 45 initially guided axially upwards, then in the third tube bundle section 30 radially again from outside to inside as in the passage through the first tube bundle section 28 and after axial flow through the reversing opening 5 in the upper annular baffle 26b again from the inside to the outside as in the passage through the second tube bundle section 29 after which he enters the upper ring channel 35 exit. The arrangement and the openings of the baffles 26a + b, 27 thus cause a prevailing Queranströmung the reaction tubes 9 with a correspondingly high heat transfer.

The tube bundle reactor 1 is also suitable for a second operating state, in which a heat transfer medium 8th in the liquid state in the tube bundle reactor 1 is introduced and in the course of the flow path under the influence of the reaction tubes 9 Partly evaporated reaction heat. Since the heat transfer is ensured here primarily by the evaporation process itself, is a Queranströmung the reaction tubes 9 no longer necessary, even undesirable because of the risk of water-steam separation.

For such a second operating state, the first adjusting device 4 , as in 1 shown, moved down to the reversal opening 5 of the lower annular baffle 26a at least partially closed. The first adjusting device 4 is in the first operating state (forced circulation) close to the bottom of the disc-shaped baffle 27 , In the second operating state (natural circulation), it is moved downwards into the area of the reversal opening 5 of the lower annular baffle 26a guided. The adjusting device 4 closes the reverse opening 5 preferably not completely, but leaves a free flow area in the range of 1 to 20%. The heat carrier 8th now flows increasingly over the bypass openings 7 of the annular baffle 26a in the second tube bundle section 29 , whereby the cross-flow component is greatly reduced.

About the bypass openings 7 in the overlying baffles 27 . 26b the heat transfer medium flows 8th now also axially reinforced in the following tube bundle sections 29 . 30 . 31 , so that here, too, the Axialstromanteil increases significantly. Preferably, all baffles 26a + b, 27 Main bypass openings 42 with a minimum size to always ensure the passage of a gas-liquid mixture.

In the upper annular baffle 26b are located in the tube-free outer ring 15 the steam outlet openings 2 which, in the case of the second operating state, in which there is a steam-water mixture with a predominant vapor volume fraction in the upper region, are open. In this way, in particular, the gaseous portion of the heat carrier 8th better escape to the top. Thus, at the bottom of the baffle 26b Areas with high vapor content, which hinders the heat transfer, are avoided. The 3 shows two embodiments of within the pressure space 18 located first and second adjusting devices 4 . 3 for reverse openings 5 and steam discharge openings 2 in a reactor design with alternating opposite baffles 46 , The first adjusting device 4 is designed as a flap, which on the inner wall 45 the reactor shell is hinged and from an open position in which it the deflection 5 releases, is pivotable to a closed position in which they the reverse opening 5 essentially closes. The second adjusting device 3 is designed as a lid, which by means of an actuating device designed as a lever 41 from a closed position, in which the lid 3 the steam outlet opening 2 essentially closes, can be brought into an open position in which the lid 3 the steam outlet opening 2 releases.

The first adjusting device 4 for a reversal opening 5 is in the first operating state (forced circulation) open to the tube bundle 10 transversely flowing liquid heat transfer medium 8th to allow a free passage in the next tube bundle section. In a second operating state (natural circulation) with partially evaporating heat transfer medium 8th the heat transfer from the reaction tube outer wall to the heat carrier 8th achieved primarily by the formation of bubbles. The guide of the heat carrier 8th transverse to the reaction tubes 9 is no longer necessary or undesirable in this case. The primary goal is now the gas content of the heat carrier 8th as quickly as possible without dead zones over the entire reactor cross section in Rohrachsrichtung from the pressure chamber 18 of the reactor 1 to lead out. By moving the first adjustment 4 in the direction of the closed position, the flow resistance through the reversal opening 5 clearly increased. The heat carrier 8th is forced, primarily directly over the bypass openings 7 the baffles 46 to flow into the next tube bundle section. Through a Restöffnungsquerschnitt the reverse opening 5 next to the tube bundle 10 can primarily the gas content of the heat carrier 8th escape slightly upwards.

In contrast to the reversal opening 5 is the steam outlet 2 closed in the first operating state, so that the liquid heat carrier 8th there is forced into the cross flow and across the tube bundle 10 flows through. In the second operating state, however, the steam discharge opening 2 at least partially open so that there is a flow cross-section is created, which is preferably as large as the Restöffnungsquerschnitt the reversal opening 5 in the second operating state. The heat carrier 8th so on the one hand over the entire drilled area over the bypass openings 7 flow into the subsequent tube bundle section, on the other hand, the gas content of the heat carrier 8th slightly above the tube bundle 10 located steam outlet openings 2 escape to the next tube bundle section. The flow area of the return and the steam outlet openings 5 . 2 is not particularly limited in its shape and size. From a flow perspective, a continuous porous flow cross-section along the tube bundle outside is advantageous, such. B. a perforated plate. This makes a corresponding large-scale adjustment required. Several smaller flow cross sections simplify the adjustment construction.

The actuators 41 for the adjusting devices 4 . 3 are in the embodiments shown within the pressure chamber 18 arranged. You can look through the reactor jacket 13 extend through, for example by means of a small opening 47 , on the one hand so large that a perfect function is possible, on the other hand so small that a flow influencing the heat carrier 8th in the pressure room 18 of the reactor 1 is minimized.

Because the adjusting devices 4 . 3 be actuated only in the course of changes in the operating condition, which usually also simultaneously the heat transfer medium 8th from the reactor 1 is removed, so there are simple nozzles 48 at the reactor jacket 13 as a wrapper for the actuators 41 at. The pillars 48 be through blind cover 49 locked. An elaborate pressure-tight lead out of the actuators 41 from the pressure room 18 can be omitted.

As explained above, the requirements for the bypass openings 7 in forced circulation and in natural circulation significantly different. So should z. B. forced circulation in the radial flow, the baffles 27 that the heat carrier 8th lead radially outwards, free of bypass openings 7 be so that the flow rate is not reduced even with increasing flow cross section. By contrast, all baffles should be in natural circulation 26a + b, 27 as many and large bypass openings 7 to allow unimpeded axial flow without water-vapor separation. It has been found that solely by adjusting the flow resistance in at least part of the bypass openings 7 a generic tube bundle reactor 1 from one operating state to the other operating state is convertible.

4a and 4b show two examples of adjusting 6 for changing flow resistances in or flow cross sections of main bypass openings 42 , The 4a shows a section of a baffle 26a + b, 27 similar to in 2 , The flow through the main bypass openings 42 can here with the help of a rake-like adjustment 6a , which is movable in Rohrachsrichtung be changed. In the illustrated open position, the heat transfer medium flows 8th between the ridges of the rake 6a and the reaction tubes 9 from one tube bundle section to the next. Another example of adjusting devices 6 for adjusting the flow resistance in bypass openings 7 is in 4b shown. Here is a plate-shaped adjustment 6b right on the with main bypass openings 42 provided deflector 26a + b, 27 on. In open position leaves the plate 6b from the main bypass openings 42 emerging heat carrier 8th through appropriate openings 50 pass freely. By moving the plate 6b normal to the reaction tubes 9 Can the main bypass openings 42 of the baffle 26a + b, 27 be completely or partially closed.

The flow resistance of reverse openings 5 not only in the axial direction of the reactor 1 be changed, as in 1 and 3 represented, but also achsnormal, like 5a and 5b demonstrate. Here is one with windows 51 provided cylinder 52 behind the outlet of the heat carrier 8th from a tube bundle section on the inner tube circle 12 arranged, with the webs 53 between the windows 51 have at least the same opening angle as the windows 51 , In this cylinder 52 there is a second concentric cylinder 54 with projection-like windows 55 and jetties 56 , The second, inner cylinder 54 is via a perforated conical connecting structure 57 for a z. B. with a rotatable rod located in the reactor axis 58 connected and rotatable by this 59 and on the other with the flow direction of the heat carrier 8th next tube bundle section in flow communication. By the rotation of the inner cylinder 54 the flow cross-section is reduced and increases the flow resistance. An analogous construction is - not shown here - on the outer tube circuit 11 possible. The drive of the moving, with windows 55 provided cylinder 54 , z. B. with a Gear transmission. The window sizes of the inner cylinder 54 For example, can also be changed with an axially movable cylinder slide, not shown here with appropriate design of the window.

The 6 shows a variant of in 1 respectively. 3 described adjusting devices 4 . 3 for reverse openings 5 and for steam outlet openings 2 in a tube bundle reactor 1 with alternating opposite baffles 46 . 46a . 46b , In this embodiment, an adjusting device 60 (in 6 the right) are arranged to have a reversal opening in one position 5 and in another position a steam discharge opening 2 essentially to close or to adjust their flow resistance. In the in 6 shown position closes the right adjustment 60 the local steam outlet openings 2 and gives the reverse openings 5 in the adjacent baffles 46 free, so that operation with meandering forced circulation of the heat carrier 8th is possible. The middle and the left adjustment lock 3a . 3b centric or in the tube-free outer ring 15 arranged steam discharge openings 2a . 2 B , In contrast to 1 , in which the centric opening is the reversal opening of an annular baffle, is in 6 the centric opening the steam outlet opening 2a a - in the illustrated position of the right adjustment 60 - On one side of the right reactor wall 45 from extending baffle 46 ,

As in 6 shown, several (here: three or two superimposed) adjusting devices 60 . 3a . 3b with the same actuator 61 . 41a . 41b (Here: an actuating rod) and be moved in this way simultaneously.

The right and the middle adjustment devices 60 . 3a are not designed here as resting on an opening lid, but as used in an opening adjusting devices. This training makes increased demands on the manufacturing accuracy, since here the tolerance dimensions are smaller than in the execution of the adjustment as a lid. The left adjusting device 3b is against it like in 1 designed as a lid.

For a boiling water operation, ie natural circulation operation, the in 6 right adjusting device 60 shifted downwards by a tube bundle section, so that the adjusting devices 60 , before the steam outlet openings 2 in baffles 46a had closed, now the reverse openings 5 the adjacent (alternately arranged) baffles 46b close and the heat carrier 8th in an axial flow through (not shown) by-pass openings 7 in the baffles 46 is forced. Here are the middle and the left adjustment 3a . 3b moved to a position in which they have the appropriate steam discharge openings 2a . 2 B release.

The actuators 61 . 41a . 41b for the adjusting devices 60 . 3a . 3b do not lead in this variant through the reactor jacket 13 but through the upper tubesheet 16 , They are each with a lifting cylinder 62 connected, all in the gas inlet space of the upper gas inlet hood 20 are arranged. The lifting cylinders 62 For example, can be configured as a hydraulic lifting device with the existing heat transfer medium as the working medium. So no special demands on the seals of the push rods 63 the lifting cylinder 62 be placed because any leaks easily in the heat transfer space 18 can be directed. The housing 64 the lifting cylinder 62 are with the tubesheet 16 ie with the pressure chamber 18 , tightly connected and each have a passage opening 65 on that with an access opening 66 to the pressure room 18 flees. Through the passage opening 65 protrudes a push rod 63 the lifting cylinder 62 protruding, with the associated operating rod 61 . 3a . 3b connected is. In a further preferred embodiment, in the gas inlet hood 20 a neck 67 be arranged with an actuating rod 61 Aligns and through the entire associated adjustment 60 can be pulled out for maintenance and repair work. Alternatively, all adjusting devices 60 . 3a . 3b simultaneously actuated and removable when the entire upper hood is released from the reactor.

If a plurality of adjusting devices designed as covers are fastened to the same actuating device and if they are to be removable from the pressure chamber together with them, it is advantageous if these covers become smaller from top to bottom in the manner of an inverted Christmas tree, so that the covers are replaced by the respective ones Overlying openings are easily passed.

In 7 is an embodiment of a tube bundle reactor according to the invention 1 shown, which has a heat transfer circuit, which is particularly easy to switch from boiling water operation to forced circulation operation and vice versa. As already explained above, the cooling concept in boiling-water operation is based on that in the reaction tubes 9 Resulting heat of reaction by the evaporation process of a heat carrier 8th is dissipated. The vapor pressures of commonly used Boiling temperatures are quite high, so that the reactor 1 is designed as a pressure vessel with correspondingly large wall thicknesses. To limit the wall thickness of the ring lines 32 . 35 for the even distribution of the heat carrier 8th on the circumference of the reactor 1 These are performed as well as the feeding and discharging pipes in the illustrated embodiment with a round cross-section. The connection of the ring lines 32 . 35 with the pressure room 18 of the reactor 1 takes place over a multiplicity of short connection lines 68 , That in the pressure room 18 of the reactor 1 resulting water-vapor mixture 69 rises due to its lower density by at least one riser 70 in a steam drum 71 where it is separated into its constituents vapor and liquid phase. The steam 72 is over an upper neck 73 fed to another use. The liquid phase 74 is according to the invention via only one down pipe 75 back to the lower part of the reactor 1 via a lower ring channel 32 recycled. The as steam 72 the steam drum 71 and thus the heat transfer circuit leaving water quantity is added as feed water to the heat transfer circuit at suitable - not shown in the figure - body again. The reactor 1 is isolated in the usual manner (not shown here) against heat losses so as not to reduce the vapor yield.

The only downfall 75 also has in its vertical part of an upper closable branch pipe 76 and a lower closable branch pipe 77 , between which there is a shut-off valve 78 located. At the upper and lower branches 76 . 77 in the downpipe 75 can, for. B. when changing the operating condition, in a simple manner, a system for another liquid or gaseous heat transfer medium can be connected, which can be performed in forced circulation, if that between the branch pipe 76 . 77 lying shut-off valve 78 is closed. Instead of the shut-off valve 78 can z. B. also a plug-in disk for closing the down pipe 75 be used. At least one of the branch pipes 76 . 77 can also be used to supply additional feed water or devices for measuring pressure and / or temperature.

The steam drum 71 is on the down pipe 75 stored, in turn, a vertical fixed point 79 with a level 80 owns which at the level 81 the bedding 82 of the main reactor part 83 lies. In both operating states, the heat transfer system has almost the same temperature at each point. As usually the main reactor part 83 and the piping 70 . 75 consist of materials with the same coefficient of thermal expansion, stretch the main reactor part 83 and the piping 70 . 75 in the transition from cold to warm state when starting (and vice versa also when driving off) in the same way and thermal stresses are largely avoided due to this constructive action. This can be costly measures to compensate for the thermal expansion omitted and is a compact design allows.

The features of the invention are not limited to the illustrated examples. For example, they can be combined with each other in any suitable way. Forced circulation operation with a purely gaseous heat transfer medium is also possible.

In particular, the adjusting devices are not limited to the illustrated embodiments. So z. B. adjusting conceivable that use the buoyancy.

Furthermore, it is also thought to arrange the baffles to the steam discharge openings upwards inclined or form with an upwardly inclined bottom. The steam is guided by the inclined surfaces to the steam discharge openings and thus improves the steam discharge.

8th schematically shows a flow diagram with a tube bundle reactor 100 and the components of an embodiment of a temperature control device according to the invention 102 ,

The tube bundle reactor shown here 100 is executed in a single-tone He has a variety of catalyst-filled reaction tubes 103 on that in a tube bundle 104 are arranged. The reaction tubes 103 are sealing in an upper tube sheet 105 and in a lower tube sheet 106 attached. The tube sheets 105 . 106 are on their exterior with a cylindrical reactor shell 107 connected to the tube bundle 104 encloses. tube sheets 105 . 106 and reactor jacket 107 together form a pressure room 108 in which a normal heat transfer medium 109 the reaction tubes 103 lapped. The tube bundle 104 can z. B. be drilled over a full-area cross-section or executed in a ring-shaped with a tube-free interior. It is also common between an annular tube bundle 104 and the reactor jacket 107 a tubular outer ring formed. The upper tube sheet 105 can through an upper flange with an upper gas inlet hood 110 be connected, the bottom tube sheet 106 through a lower flange with a lower gas outlet hood 111 , At high operating pressures on the reaction gas side and / or the Heat transfer side, it may be advantageous to replace the flange by welded joints, as in 8th shown. The reaction tubes 103 open into the gas inlet hood 110 and in the gas outlet hood 111 , The gas inlet hood 110 has a gas inlet nozzle 112 , the gas outlet hood 111 a gas outlet 113 on. The heat carrier 109 is through suitable flow guides through the pressure chamber 108 of the tube bundle reactor 100 guided. He is in the illustrated reactor 100 over an upper and lower ring line 114 . 115 and respective upper and lower connecting lines 116 . 117 on the circumference of the reactor 100 distributed or collected. The associated, not shown here, heat transfer system, with a circulation device, temperature control devices and possibly other components, is at first (in 8th right) neck 118 the ring lines 114 . 115 connected. Otherwise, the tube bundle reactor 100 in the 8th . 9a and 9b not shown adjusting devices 4 . 51 - 56 for adjusting the flow resistance in reverse openings 5 and / or steam discharge openings 2 . 2a . 2 B with associated adjusting devices 3 . 3a . 3b and / or adjusting devices 6 . 6a . 6b for adjusting the flow resistance in bypass openings 7 . 42 on, as stated earlier for the tube bundle reactors 1 are described. To avoid repetition, reference is hereby made.

The tempering device 102 has a first circulating fan 119 on, that to the lower ring line 115 connected. To the upper ring line 114 is a cooler 120 connected, which is a heat exchange part 121 and a second blower 122 comprising the ambient air through the heat exchange part 121 promotes. In the flow direction behind the radiator 120 is a heater 123 arranged. Preference is given to an electric heater, because electrical power is usually readily available and the heating power is variable over a wide range. The heating power is via a control device 124 adjustable. Between heaters 123 and first circulating fan 119 is a pressurized gas supply 125 connected. This is designed as a compressor, which has a check valve 126 Promotes ambient air. The compressor 125 is part of a pressure regulator 127 that also has a pressure transducer 128 and a relaxation valve 129 having.

Hereinafter, the operation for a first operation state and a second operation state will be described. Under a first operating state here is the normal operation of the tube bundle reactor 100 understood, in the reaction gases 130 in the reactor 100 be in it, in this chemically react and be led out of this again, wherein the pressure in the room 108 of the tube bundle reactor 100 circulating heat transfer medium 109 the reaction temperature is controlled. A second operating state is understood below to mean a conditioning process in which the reactor 100 on the tube side with a gas 131 is flowed through, which has a different composition than that used in the first operating state. In addition, in this second operating state of the heat transfer medium 132 other properties than those in the first operating state. In particular, it is a compressed gas and also has z. Example, a different composition, a different temperature, or a combination of these properties. The temperature control device according to the invention 102 preferably finds application for this second operating state. In this operating state, for example, a gas for regeneration of the catalyst through the reaction tubes 103 guided and the temperature of the heat carrier 132 significantly increased over that of the first operating state using a gaseous heat carrier.

In the first operating state, the reaction gas occurs 130 over the upper gas inlet nozzle 112 in the upper gas inlet hood 110 one, there is on the upper tube sheet 105 distributed, flows through the reaction tubes 103 and through the lower gas outlet 113 the lower gas outlet hood 111 from the reactor 100 out again. Likewise, it is possible the reaction gas 130 from the bottom up through the reactor 100 respectively.

The reactions occurring in the first operating state are compared to those in the pressure chamber 108 circulating heat transfer medium 109 controlled. In this case, the heat carrier 109 either in the lower or in the upper loop 115 . 114 be introduced and from the other ring line 114 . 115 be led out again. In the case of cooling an exothermic reaction with the aid of an evaporating heat carrier, preferably water, the liquid heat carrier 109 in the lower ring channel 115 introduced and distributed over the circumference. Over a variety of lower connecting lines 117 he will be in the pressure room 108 of the reactor 100 led in and there with suitable, not shown here, Strömungsleiteinrichtungen evenly over the cross-sectional area of the reactor 100 distributed. That in the reactor 100 resulting liquid-vapor mixture is through a variety of upper connecting lines 116 in the upper ring channel 114 passed and from this through an upper port from the reactor 100 led out.

The temperature control device according to the invention 102 preferably finds application for the second operating state. Here, the reaction gas 130 replaced by a conditioning gas 131 , whose composition, pressure and temperature depends on the type of catalyst used. In this second Operating state, the heat carrier system of the first operating state is replaced or supplemented by the temperature control device according to the invention 102 , For this purpose, in the case of regeneration, first the liquid heat carrier 109 from the mantle room 108 of the tube bundle reactor 100 away. The of the ring lines 114 . 115 wegführenden heat transfer conduits of the heat transfer system for the first operating state can be shut off to avoid unwanted bypasses. The temperature control device according to the invention 102 is via two connecting cables 133 . 134 with flange connections 135 . 136 preferably on separate nozzles 137 . 138 at the upper ring line 114 and at the lower loop 115 of the tube bundle reactor 100 connected. Alternatively, the connection can be made at other locations of the heat carrier lines, preferably close to the tube bundle reactor 100 ,

As a heat carrier 132 the second operating condition compressed gas is guided in a closed circuit. The compressed gas 132 contains air, nitrogen, carbon dioxide, water vapor or a mixture of these. It will be with the first circulating fan 119 in the tube bundle reactor 100 promoted. To ensure a good heat transfer, the compressed gas 132 with Strömungsleiteinrichtungen preferably across the tube bundle 104 guided, if necessary using special devices. The compressed gas 132 occurs over the upper connecting lines 116 from the reactor 100 out, in the upper ring channel 114 collected and emerges from this from an upper nozzle 137 out. Depending on the nature of the conditioning process is the reaction tubes 103 either heat supplied or heat dissipated by these. Accordingly, the compressed gas 132 either cooled or heated. In the case of cooling flows through the upper ring channel 114 upcoming compressed gas 132 a cooler 120 , which is preferably designed as an air cooler. Alternatively or additionally, the compressed gas 132 through an in 1 not shown mixing device are cooled, in which the compressed gas 132 is cooled by direct injection of water.

If the conditioning process is endothermic, so absorbs heat, so the compressed gas 132 in the heater 123 heated. Subsequently, the compressed gas 132 over the first circulating fan 119 back into the tube bundle reactor 100 promoted. The series-connected components of the temperature control 102 can also be changed in their order. So it may be useful to arrange the heater only in the flow direction behind the first rotary fan or parallel to this. To maintain the operating pressure in the heat transfer system is the pressure control system 127 intended. The pressure transducer measures 128 the pressure. If the pressure is too low, this will be through the compressor 125 increased, which is connected to a suitable location in the heat transfer system. If the pressure is too high, an expansion valve will be activated 129 open.

As an example of the efficiency of the temperature control device according to the invention 102 and the process according to the invention, the activation of a new catalyst bed in a tube bundle reactor 100 calculated with radial guidance of the heat carrier for the subsequent normal operation. For comparison, the activation in case 1 was calculated with air at ambient pressure and in case 2 with compressed air.

Technical specifications:

• 13300 reaction tubes with outer diameter 30 mm and length 8 m.
• Sheath diameter 4900 mm.
• Inlet and outlet connection of the heat transfer medium nominal diameter DN800.

The activation should be carried out at about 300 ° C and a heat of 200 KW are discharged from the reactor.

Case 1: Circulation of air at 300 ° C inlet temperature at ambient pressure through a tempering device with 50000 m ³ / h flow rate.

Case 2: Circulation of air with 300 ° C inlet temperature at 20 bar absolute pressure by a tempering device according to the invention with 19000 m ³ / h flow rate. Table 1: Comparison calculation case 1 Case 2 mass flow kg / h 30400 231000 Pressure loss of the circulation Pa 5830 15420 Theoretically required circulation capacity kW 81 81.4 Temperature increase of the air in the reactor K 22.7 3.0 Average heat transfer coefficient air / tubes W / m2K 60 190

As can be seen from the results given in Table 1, the increase in the air temperature in the reactor in case 1 is 22.7 K and in case 2 only 3.0 K. The average heat transfer coefficient air / reaction tubes in case 1 is 60 W / m2K and in the case of 2 190 W / m2K. In case 2, a much better degree of temperature control can be achieved, ie the temperature equality and the heat transfer to the reaction tube 103 achieve, with approximately the same required circulation capacity.

In the 9a and 9b is a tempering device according to the invention 102 as compact on a transportable frame 139 mounted unit shown. The frame 139 can, as shown here, with lifting lugs 140 lifted and lifted by a dolly to the site. There are also other constructions possible. For example, the frame can be designed as a container with skids and a lifting connection to which a towing hook of a truck can begin to pull the container onto its bed. After installation, the connection is made via a connecting cable 134 the pressure side and a connecting cable 133 the suction side. The of the ring lines 114 . 115 of the reactor 100 upcoming reactor connections must be connected to the connection positions of the temperature control 102 match as well as possible. However, the connection positions can be practically only limited adhered to, for example due to tolerances or local conditions that cause a positional offset. At least one of the connecting cables 133 . 134 therefore has a flange connection 135 . 136 with elastic intermediate piece 141 . 142 , As a result, misalignments of connections in a certain range can be compensated. Are the lines connected to each other, so are the joints with the elastic spacers 141 . 142 through adjustable strain reliefs 143 . 144 fixed in position for absorbing the internal pressure forces.

The individual components of the temperature control 102 are on the transportable frame 139 arranged in a compact, space-saving unit. The connection cable 133 the suction side leads to the cooler 120 which is designed here as an air cooler. From there leads a compressed gas line 145 in the electric heater 123 and from there into the first circulating fan 119 from where they have an elastic intermediate piece 142 to the reactor 100 leads. The pressure is by one beside the electric heater 123 arranged compressor 125 maintained. The pressure line 146 from the compressor 125 leads above the electric heater 123 to the supply line to the first blower 119 , However, the connection can also be made elsewhere, for. B. via a short connecting line from the compressor 125 to the pipeline 145 between cooler 120 and electric heaters 123 , The control devices are not shown in this embodiment.

The features of the invention are not limited to the illustrated examples. For example, they can be suitably combined with each other. The device is further applicable mutatis mutandis in Mehrzonigen tube bundle reactors, as they are for. In EP 1 590 076 A1 are described, with connection to the heat carrier side of one or more zones. The device is particularly suitable for use in non-operational conditions and processes. It can be used for. As for the activation and regeneration of the catalyst, also for the targeted deactivation of the catalyst by an oxidation process, when a highly reactive catalyst is to be removed from the interior of the reactor, or for calcination processes.

The temperature control device can be particularly simple 102 be switched into the heat transfer circuit when the tube bundle reactor 1 . 100 only one down pipe 74 has, according to the in 7 illustrated embodiment. It is irrelevant whether the heat transfer medium via ring lines through the reactor shell (as in 7 shown) or is guided over supply and discharge pipes, which extend axially through the tube sheets. Both embodiments are in combination with the tempering device 102 of the invention. The connecting cables 134 . 133 the tempering device 102 be in the embodiment according to 7 to the branch pipe 76 . 77 and in the embodiments according to 8th . 9a . 9b to the neck 137 . 138 connected. The branch pipes 76 . 77 and the neck 137 . 138 thus correspond to each other.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2004/052524 A1 [0003]
• WO 2004/052776 A1 [0004]
• US 5615738 [0006]
• US 5303276 [0008]
• EP 0382098 A2 [0009]
• US 3147743 [0010]
• DE 102007024934 A1 [0040]
• DE 2207166 A1 [0043]
• EP 1569745 A1 [0043]
• DE 3819357 A1 [0050]
• WO 2009/118372 A1 [0051]
• EP 1590076 A1 [0137]

Claims (31)

A shell-and-tube reactor for catalytic gas phase reactions, comprising a bundle of vertically arranged reaction tubes, upper and lower tubesheets tightly connected to the upper and lower ends of the reaction tubes, respectively, through which the reaction tubes terminate in gas supply and gas discharge means, a reactor shell containing the Tubular bundle encloses and is tightly connected to the tube sheets to form a pressure chamber with them, in which the reaction tubes are lapped by a heat transfer during operation, at least one baffle which extends transversely through the tube bundle and the heat transfer medium imposes a transverse flow and a reversal opening for leaves the heat carrier free, so that the heat transfer medium flows through the tube bundle in its longitudinal direction, and with bypass openings, which are arranged in the at least one deflecting plate in its drilled region, characterized by an adjusting device ( 4 . 51 - 56 ) for adjusting the flow resistance in the reversal opening ( 5 ), wherein the adjusting device ( 4 . 51 - 56 ) from a first position in which the flow resistance is a meandering inversion of the flow direction of a predetermined Teilstommenge of the heat carrier ( 8th ), in which at least a second position is movable, in which the flow resistance is increased so far that this amount of partial flow is reduced. Tube bundle reactor according to claim 1, characterized in that the adjusting device ( 4 ) is arranged in one position, the reversal opening ( 5 ) close. A shell-and-tube reactor for catalytic gas phase reactions, comprising a bundle of vertically arranged reaction tubes, upper and lower tubesheets tightly connected to the upper and lower ends of the reaction tubes, respectively, through which the reaction tubes terminate in gas supply and gas discharge means, a reactor jacket containing the Tubular bundle encloses and is tightly connected to the tube sheets to form a pressure chamber with them, in which the reaction tubes are immersed in operation by a heat transfer medium, at least two baffles which extend transversely through the tube bundle, are arranged one above the other in the longitudinal direction of the reaction tubes, the Heat transfer forces a transverse flow and each leave a reversal opening for the heat carrier, so that the heat transfer medium flows through the tube bundle in the longitudinal direction, characterized in that in the pressure chamber ( 18 ) at least one pipe-free area ( 14 . 15 ) is formed, in a first of the baffles ( 26b . 46a ) in the tube-free area ( 14 . 15 ) outside the reversal opening ( 5 ) at least one steam discharge opening ( 2 . 2a . 2 B ) is formed and the second baffle ( 26a . 46b ) in the tube-free area ( 14 . 15 ) outside the reversal opening ( 5 ) is substantially closed, and that an adjusting device ( 3 . 3a . 3b ) for each steam outlet ( 2 . 2a . 2 B ) is formed, wherein the adjusting device ( 3 . 3a . 3b ) between a closed position in which the steam outlet ( 2 . 2a . 2 B ) and an open position in which the steam outlet ( 2 . 2a . 2 B ), is movable. Tube bundle reactor according to claim 2 and 3, characterized in that the at least one vapor discharge opening ( 2 ) of the first deflection plate ( 46a ) near the reversal opening ( 5 ) of the second deflection plate ( 46b ) is arranged, and that the adjusting device ( 60 ) is adapted to, in an open position, the reversal opening ( 5 ) close. A tube bundle reactor according to claim 3, characterized in that steam discharge openings ( 2 . 2a . 2 B ) are arranged in the form of a row or a ring or on a compact surface. A shell-and-tube reactor for catalytic gas phase reactions, comprising a bundle of vertically arranged reaction tubes, upper and lower tubesheet, which are tightly connected to the upper and lower ends of the reaction tubes and through which the reaction tubes open into gas supply and gas discharge means, a reactor jacket, which encloses the tube bundle and is tightly connected to the tubesheets in order to form a pressure space with them, in which the reaction tubes are surrounded by a heat carrier during operation, at least one baffle extending transversely through the tube bundle and the heat transfer medium is cross-flow forces and leaves open a reversal opening for the heat carrier, so that the heat carrier flows through the tube bundle in its longitudinal direction in a meandering manner, and with bypass openings, which are arranged in the at least one deflecting plate in its drilled region, characterized by an adjusting device ( 6 . 6a . 6b ) for adjusting the flow resistance in at least part of the bypass openings ( 7 . 42 ). Tube bundle reactor according to claim 6, characterized in that the adjusting device ( 6 . 6a . 6b ) is adapted to in one position the bypass openings ( 7 . 42 ) to close. Tube bundle reactor according to one of claims 1 to 7, characterized by an actuating device ( 40 . 41 . 41a . 41b . 58 . 61 ), with which the adjusting device ( 3 . 3a . 3b . 4 . 51 - 56 . 60 ) is movable from one position to another position. Tube bundle reactor according to claim 8, characterized in that the actuating device ( 41a . 41b . 61 ) with several adjusting devices ( 3a . 3b . 60 ) is connected and these operated simultaneously. Tube bundle reactor according to one of the preceding claims, characterized in that the actuating device ( 41 ) within the pressure chamber ( 18 ) is arranged. Tube bundle reactor according to claim 10, characterized in that the pressure chamber ( 18 ) a closable neck ( 48 ), through which the actuating device ( 41 ) from outside the pressure chamber ( 18 ) is operable. Tube bundle reactor according to claim 11, characterized in that the actuating device ( 41 ) and the associated) adjusting device (s) ( 3 ) through the neck ( 48 ) Can be mounted and disassembled. Tube bundle reactor according to one of claims 10 to 12, characterized in that the actuating device ( 41a . 41b . 60 ) by means of a drive element ( 62 ) is a housing ( 64 ), which communicates with the pressure chamber ( 18 ) is tightly connected and a passage opening ( 65 ) having an access opening ( 66 ) to the pressure room ( 18 ) and from which a movable element ( 63 ) out of the housing ( 64 ) protruding with the actuating device ( 41a . 41b . 60 ) connected is. Tube bundle reactor according to claim 13, characterized in that the drive medium of the drive element is the same medium which serves as heat carrier ( 8th ) is used. Tube bundle reactor according to claim 13 or 14, characterized in that the drive element ( 62 ) is a lifting cylinder. Tube bundle reactor according to one of the preceding claims, characterized by a combination of the features of at least two of claims 1, 3 and 6. Tube bundle reactor according to one of the preceding claims, characterized by a steam drum ( 71 ), which are above the pressure chamber ( 18 ) is arranged and via at least one riser ( 70 ) and only one down pipe ( 75 ) with the pressure chamber ( 18 ) is in fluid communication with the down pipe ( 75 ) a shut-off device ( 78 ) and before and after the shut-off device ( 78 ) at least one closable branch ( 76 . 77 ) having. Tube bundle reactor according to claim 17, characterized in that the downpipe ( 75 ) outside and along the pressure chamber ( 18 ) runs. Tube bundle reactor according to claim 17 or 18, characterized in that the steam drum ( 71 ) on the downpipe ( 75 ) is stored. Tube bundle reactor according to one of the preceding claims, characterized by a tempering device ( 102 ) to its tempering by means of a tempering gas ( 132 ), wherein the tempering device ( 102 ) with a heat transfer inlet ( 77 . 138 ) and a heat transfer outlet ( 76 . 137 ) of the pressure chamber ( 18 . 108 ) can be brought into flow connection and the temperature control gas ( 132 ) the tempering device ( 102 ) and the pressure chamber ( 18 . 108 ) flows through the circuit, with a gas supply ( 125 ), a heating device ( 123 ) for the tempering gas ( 132 ), a conveyor ( 119 ) for the tempering gas ( 132 ), wherein the gas supply a compressed gas supply ( 125 ). Tube bundle reactor according to claim 20, characterized in that the pressurized gas supply is a compressor ( 125 ) having. Tube bundle reactor according to claim 20 or 21, characterized in that the compressed gas ( 132 ) has a pressure in the range of 3 to 100 bar, preferably in the range of 5 to 50 bar and particularly preferably in the range of 10 to 30 bar. Tube bundle reactor according to one of claims 20 to 22, characterized in that it is mounted on a transportable frame ( 139 ) is mounted. Tube bundle reactor according to one of claims 20 to 23, characterized by two connection lines ( 134 . 133 ) for connection to the heat transfer inlet ( 77 . 138 ) or the heat carrier outlet ( 76 . 137 ) of the pressure chamber ( 18 . 108 ), of which at least one is an elastic intermediate piece ( 141 . 142 ) having. Tube bundle reactor according to claim 24, characterized in that the elastic intermediate pieces ( 141 . 142 ) adjustable strain reliefs ( 143 . 144 ) for receiving internal pressure forces. Tube bundle reactor according to one of claims 20 to 25, characterized in that the temperature control gas ( 132 ) Contains air, nitrogen, carbon dioxide, water vapor or a mixture thereof. Tube bundle reactor according to one of claims 20 to 26, characterized by a cooling device for cooling the tempering gas ( 132 ), which is designed to inject water directly into the temperature control circuit. Tube bundle reactor according to one of claims 20 to 27, characterized by regulating devices ( 124 . 127 ) for controlling the temperature and the pressure of the tempering gas ( 132 ). Method for tempering a tube bundle reactor ( 1 . 100 ) according to one of the preceding claims, by means of a tempering gas ( 132 ), wherein the pressure chamber ( 18 . 108 ) Is part of a heat carrier circuit, in which the temperature control gas ( 132 ), comprising the following steps: a) providing a temperature control device ( 102 ) according to any one of claims 20 to 28; b) switching the temperature control device ( 102 ) in the heat transfer circuit; c) filling the heat transfer medium circuit with the tempering gas ( 132 ) with a predetermined pressure; and d) circulating the tempering gas ( 132 ). A method according to claim 29, characterized in that for conditioning a catalyst bed in a tube bundle reactor ( 1 . 100 ), whose heat transfer circuit in the production phase of a liquid or teilverdampfenden heat transfer ( 8th . 109 ) is passed through, while step d) the following steps are carried out: e) increasing the temperature and optionally the pressure of the tempering gas ( 132 ) to the starting temperature of the conditioning process; and f) passing the conditioning gas ( 131 ) through the catalyst bed. A method according to claim 29 or 30, in each case in conjunction with a temperature control device according to claim 23, characterized in that the step a) transporting the temperature control device ( 102 ) to the tube bundle reactor ( 1 . 100 ) and after completion of the tempering process, the temperature control device ( 102 ) is transported away.

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