WO2016055452A1

WO2016055452A1 - Reactor for carrying out gas phase reactions using a heterogeneous catalytic converter

Info

Publication number: WO2016055452A1
Application number: PCT/EP2015/073015
Authority: WO
Inventors: Gerhard Olbert; Carlos TELLAECHE HERRANZ; Roland Bauer
Original assignee: Basf Se
Priority date: 2014-10-07
Filing date: 2015-10-06
Publication date: 2016-04-14

Abstract

The invention relates to a cylindrical reactor (R) with a vertical longitudinal axis for carrying out heterogeneous catalyzed gas phase reactions by converting a gaseous educt stream into a product gas mixture, having a cylindrical reactor jacket (RM) and a concentric inner cylinder (I), which divides the inner area of the reactor into an outer annular chamber (RR) and a central inner chamber (IR). In-built heterogeneous catalytic converters are contained in the outer annular chamber (RR), comprising a supply line (1) for the gaseous educt stream in an intake segment (ES) of the outer annular chamber (RR) and a discharge line (2) for the product gas mixture from an outlet segment (AS) of the outer annular chamber (RR). The intake segment (ES) and the outlet segment (AS) are separated from each other is a gas-tight manner and a heat exchanger (W) is arranged in the central inner chamber (I), wherein the gaseous educt stream is prewarmed prior to being guided into the intake segment (ES).

Description

Reactor for carrying out gas phase reactions using a heterogeneous catalyst

description

The invention relates to a reactor for carrying out gas phase reactions using a heterogeneous catalyst, which is preferably formed as a monolith, and a use of the reactor.

Ceramic or metallic monoliths as catalyst supports in exhaust gas purification or in chemical production engineering are known, and are present as parallelepiped blocks with a plurality of through channels arranged parallel to one another, with a narrow cross section, in the range of about 0.5 to 4 mm. The channels have a low flow resistance at the same time uniform accessibility of the outer catalyst surface for gaseous reaction media. This is advantageous over random heaps, in which a large pressure loss is created by countless deflections in the flow around the particles and the catalyst surface may not be used evenly. Furthermore, there are dead spaces in beds where the gas lingers longer. As a result, by-products and coking are increasingly generated, which deactivate active catalyst areas by deposition and lead to reduced sales and selectivity.

In reactors or in emission control systems, for. As in Denox systems, the parallelepiped monoliths are usually installed in such a way that the Monolithkanäle are arranged in the longitudinal direction of the cylindrical or prismatic reactor shell. Such, equipped with monoliths reactor is z. As described in WO2013 / 017609.

It was accordingly an object of the invention to further improve a reactor with internals containing a heterogeneous catalyst, wherein the internals are in particular monoliths. To be provided is an improved reactor for carrying out heterogeneously catalyzed gas phase reactions, which is structurally simple manufacturable, has a high compressive strength and easy accessibility of the internals that carry the catalyst, a simple supply and optionally intermediate feed of educts and easy accessibility Measuring sensors and analytics enabled.

In particular, an efficient preheating of the educts, preferably by recovering the heat from the product gas mixture, is to be ensured. The object is achieved by a cylindrical reactor having a vertical longitudinal axis for carrying out heterogeneously catalyzed gas phase reactions by reacting a gaseous reactant stream to a product gas mixture, with a cylindrical reactor jacket and a concentric inner cylinder, which divides the reactor interior into an outer annular space and a central inner space, wherein outer annulus internals are provided, which contain the heterogeneous catalyst, with a feed line for the gaseous reactant stream in an inlet segment of the outer annulus and with a discharge line for the product gas mixture from an exit segment of the outer annulus, wherein the inlet segment and the exit segment are gas-tightly separated from each other, and wherein a heat exchanger is arranged in the central interior, wherein the gaseous reactant stream is preheated prior to feeding it into the inlet segment.

It has been found that by the above particular formation of the space for receiving the heterogeneous catalyst, as an outer annular space bounded by two concentric cylinders, the cylindrical reactor shell and the concentric inner cylinder, excellent pressure stability of the reactor is ensured that reactions under high pressure can be carried out without the need for extremely thick reactor walls.

The inventive arrangement of a heat exchanger in the central interior of the reactor, it is possible to preheat the reactants with high efficiency, in particular with the product gas mixture, whereby a heat recovery is ensured.

The reactor of the present invention is a cylindrical, upright apparatus, preferably with a greater degree of slimming, i. a ratio of height of the reactor to the inner diameter in the range of 0.5 to 3.0, in particular in the range of 0.7 to 1.2. The greater degree of slimming has the advantage of greater compressive strength with the same wall thickness.

The reactor has a cylindrical reactor jacket, in which a concentric inner cylinder is inserted, which divides the interior of the reactor into an outer annular space and a central inner space.

Preferably, a ratio of the inner radius of the reactor shell to the outer radius of the concentric inner cylinder in the range of 1, 1 to 2.0, preferably between 1, 3 and 1, 6. The outer annulus is the same at both ends, ie, top and bottom, closed by covers. The covers are preferably designed such that they can be easily assembled and disassembled.

It is also possible to form the lower and / or upper cover in such a way that they can only be opened in partial areas through which the internals containing the heterogeneous catalyst can be installed and removed in the outer annular space.

The reactant stream is fed via a thermally compensated supply line via the inlet segment, preferably in the lower region thereof, to the heat exchanger arranged in the central interior and preheated therein by indirect heat exchange, preferably with the product gas mixture.

The heat exchanger may advantageously be designed as a plate heat exchanger.

In a further preferred embodiment, the heat exchanger is designed as a tube bundle heat exchanger. This is advantageously designed so that it does not occupy the entire height of the central interior, but that the tubesheets, in which the heat exchanger tubes are welded in the longitudinal direction of the reactor, are spaced from the respective reactor end, so that in each case a free cylindrical space, a kind of hood , remains.

The reactant stream is advantageously fed via a thermally compensated supply line to the lower region of the jacket space of the heat exchanger arranged in the central interior, flows through the same around the tubes of the tube bundle heat exchanger, and leaves the heat exchanger from preheated educt current at the upper end thereof via an opening in the inlet segment.

The preheating of the reactant stream in the heat exchanger, which is arranged in the central interior, is preferably carried out by the heat of the product gas mixture, the same from the outlet segment via an opening in the upper region, in the upper hood of the central interior, above the heat exchanger, flows and the tubes flows through it. The product gas mixture leaves the heat exchanger in the central interior via the lower hood and a thermally compensated discharge line via the outlet segment.

The inlet segment is free of internals and is a subspace (a chamber), which acts as a pre-distributor, that is, which distributes the gaseous reactant stream over the entire reactor height and thus causes a coarse flow distribution of the same over the reactor height. A further homogenization of the gaseous educt current can preferably be achieved by a rectifier, which is advantageously arranged immediately after the entry segment in the annular space over the entire height thereof.

The gaseous reactant stream flows through the complete outer annular space, wherein the gas phase reaction takes place on the heterogeneous catalyst, and the product gas mixture exits the outer annular space via the outlet segment, which closes the outer annular space to the inlet segment and is separated from it gas-tight. The exit segment is, like the entry segment, a subspace (a chamber) in the outer annulus and is a collection device for the product gas mixture over the entire height of the outer annulus.

The separation between the inlet segment and the outlet segment can be carried out by means of a partition, which can also be advantageously profiled.

In a further preferred embodiment, the separation between the inlet segment and the outlet segment can be carried out by means of a separation segment, that is to say a separation chamber, with the advantage that feed lines can be laid from outside the reactor directly into the central interior of the reactor via the separation segment, and / or the accessibility of the central interior is made possible from outside the reactor.

In the outer annulus internals are arranged, containing the heterogeneous catalyst.

As internals containing the heterogeneous catalyst, monolith modules are preferably used.

As a monolith is in a known manner, a one-piece, parallelepipedic block with a plurality of mutually parallel, continuous channels with a narrow cross-section, in the range of about 0.36 to 9 mm ² , understood. The channels are preferably formed with a square cross section, in particular with a side length of the square in the range of 0.6 to 3 mm, particularly preferably from 1, 0 to 1, 5 mm.

The monoliths are preferably formed from a ceramic material as a carrier material, whereupon a catalytically active layer, preferably by the so-called wash-coating method, is applied.

The most common material for monolithic structures is cordierite (a ceramic material consisting of magnesium oxide, silica and alumina in the ratio 2: 5: 2). Other materials whose monolith structures are commercially available are metals, Mullite (mixed oxide of silica and alumina, ratio 2: 3) and silicon carbide. Similar to cordierite, these materials have a low specific BET surface area (BET = Brunauer, Emmet and Teller) (eg for cordierite typically 0.7 m ² / g).

Monolithic ceramic elements are available with cell densities of 25 - 1600 cpsi (cells per square inch, corresponding to a cell size of 5 - 0.6 mm). By using a higher cell density, the geometric surface area increases, so that the catalyst can be used more efficiently. Disadvantages of higher cell densities are a somewhat more difficult manufacturing process, a more difficult washcoat coating and a higher pressure drop across the reactor. Furthermore, as a rule, the webs are also thinner at high cell densities, which reduces the mechanical stability of the monoliths. In cylindrical reactors, the monoliths in the edge area must be adapted by appropriate cutting. However, the pressure loss remains very low for monoliths with high cell density compared to a packed reactor (usually lower by a factor of 10), which is due to the straight Monolithkanäle.

To prepare monolithic ceramic elements, a mixture of talc, clay and alumina-providing components and silica may be prepared, the mixture mixed to form a molding compound, the mixture molded, the greenware dried and heated at a temperature of 1200 to 1500 ° C to obtain a ceramic that contains mainly cordierite and has a low coefficient of thermal expansion. Generally speaking, one can extrude a paste with corresponding rheological properties and corresponding rheological composition to a monolith carrier. The paste usually consists of a mixture of ceramic powders of suitable size, inorganic and / or organic additives, solvent (water), peptizer (acid) to adjust the pH and a permanent binder (colloidal solution or sol). The additives may be a plasticizer or a surfactant to adjust the viscosity of the paste or a temporary binder which may later be burned off. Sometimes glass or carbon fibers are added to increase the mechanical strength of the monolith. The permanent binder should improve the internal strength of the monolith.

Cordierite monoliths can be prepared from a batch consisting of talc, kaolin, calcined kaolin and alumina and together form a chemical compound of 45 to 55% by weight of SiO 2, 32 to 40% by weight of Al 2 O 3 and 12 to 15% by weight. - deliver% MgO. Talc is a material consisting mainly of magnesium silicate hydrate, Mg3Si4O10 (OH) 2. Depending on its source and purity, the talc may also be mixed with other minerals such as tremolite (CaMg3 (Si03) 4), serpentine (3Mg0.2Si02, 2H20), anthophyllite (Mg7 (OH) 2 (Si401 1) 2), magnesite (MgC03), mica and chlorite.

By extrusion, monoliths of other materials such as SiC, B4C, Si3N4, BN, AIN, Al2O3, ZrO2, mullite, Al titanate, ZrB2, sialon, perovskite, carbon and ΤΊO2 can also be produced.

Of importance in terms of the properties of the monolithic products in extrusion, in addition to the quality of the nozzle, the nature and properties of the materials used to make the moldable mixture, are also the additives added, the pH, the water content and the force used in the extrusion. The additives used in the extrusion are, for example, celluloses, CaCl 2, ethylene glycols, diethylene glycols, alcohols, wax, paraffin, acids and heat-resistant inorganic fibers. In addition to water, other solvents can be used, such as ketones, alcohols and ethers. The addition of additives can lead to improved monolithic properties, such as the formation of microcracks, which improves thermal shock resistance, better porosity and absorbency and increased mechanical strength or low thermal expansion.

The bare monolithic structure is coated with a catalyst support layer comprising one or more ceramic oxides, or a catalyst layer which already supports the catalytically active metals and the optional further (promoter) elements on the ceramic oxide support material, the coating following a Washcoat coating method is produced.

The macroporous structure of ceramic monoliths facilitates the anchoring of the washcoat layer. The manner of washcoat coating can be divided into two methods: one can (partially) fill the macroporous support with the high surface area washcoat material or deposit a washcoat as a layer in the pores of the ceramic carrier. Pore filling leads to the strongest interaction between monolith and washcoat, since most of the washcoat layer is actually fixed in the pores of the carrier and is not bound only to the outer surface of the monolith channels. This type of coating is carried out with a solution (or a sol) of the material to be deposited or with a solution containing very small colloidal particles. The disadvantage of coating by means of pore filling is that the amount of depositable coating is limited, since the pores will eventually be completely filled and the washcoat will become inaccessible.

Monoliths offer favorable conditions especially for carrying out the autothermal dehydrogenation of hydrocarbons: in particular, are closer Reactor cross sections and higher flow rates compared to random packed fixed beds feasible, so that an effective, stepped metered addition of oxygen into the hydrocarbon-containing main stream is possible. Due to the fact, compared to randomly packed fixed beds, smaller reactor cross-section, both the distributor and the fixed internals of the mixing zones are mechanically less heavily loaded, ie they hang less because of the lower anchoring length. Moreover, the main flow direction through the reactor is not limited to downflow, as in the case of randomly packed fixed beds.

After a prolonged service life, the presently recommended catalysts can normally be regenerated in a simple manner, for example by initially air in first regeneration stages, which is (preferably) diluted with nitrogen and / or water vapor, at an inlet temperature of 300 to 600 ° C. (in extreme cases up to 750 ° C), often from 500 to 600 ° C, passes through the fixed catalyst bed. The catalyst loading with regeneration gas may be, for example, 50 to 10,000 h-1 (based on the total amount of regenerated catalyst), and the oxygen content of the regeneration gas may be 0.5 to 20% by volume.

Thereafter, it is generally advisable to regenerate under otherwise identical conditions with pure molecular hydrogen or with molecular hydrogen diluted with inert gas (preferably water vapor and / or nitrogen) (the hydrogen content should be> 1% by volume).

In addition, it is also possible to extrude monoliths as Vollkatalysatormasse.

In particular, as internals containing the heterogeneous catalyst, monolith modules are provided, which are formed of monoliths with horizontally arranged substantially along concentric circles channels, which are arranged in each case to two, three or more, along each reactor radius adjacent to a row and wherein two, three or more rows of monoliths are stacked on top of each other, each monolithic module being circumferentially encased in one or more fibrous mats, and over the same in a metal sheath, leaving the end faces free of entrance or exit openings of the channels in which each monolith module (MM) completely fills the outer annulus in the radial direction, wherein in each case two or more monolith modules are combined one above the other to form planar packing units arranged radially in the annulus of the reactor, and one, two or more packing units each fill a segment in the outer annulus of the reactor over its entire height and form a catalytically active zone. Monoliths are more preferably provided as internals containing the heterogeneous catalyst, which are formed of monoliths having horizontally arranged substantially along concentric circles channels, each of which is arranged to four or more, along a respective reactor radius side by side to a row and wherein four or more rows of monoliths are stacked on top of each other, wherein each monolithic module is encased in one or more fibrous mats and over the same in a metal sheath over the periphery thereof, leaving the end faces containing the entrance or exit openings of the channels, each one Monolith module completely fills the outer annulus in the radial direction, wherein in each case two or more monolith modules are summarized one above the other to planar packing units, which are arranged radially in the outer annulus of the reactor, and wherein one, two or more packing units each fill a segment in the annular space of the reactor over its entire height and form a catalytically active zone.

In a further embodiment, as internals containing the heterogeneous catalyst, monolith modules are provided, which are formed of monoliths with horizontally arranged substantially along concentric circles channels, each of eight or more, are arranged side by side along each reactor radius and eight or more rows of monoliths are stacked on top of each other, wherein each monolith module is enclosed in the circumference of the same, leaving the end faces, the inlet or outlet openings of the channels in one or more fibrous mats and the same in a metal shell, wherein each monolith module the outer annular space in the radial direction completely fills, wherein in each case two or more monolith modules are summarized one above the other to planar packing units, which are arranged radially in the outer annulus of the reactor, and wherein one, two or more flat Packu ngseinheiten each fill a segment in the annular space of the reactor over the entire height thereof and form a catalytically active zone.

Each monolith module fills the outer annulus in the radial direction of the same completely.

Depending on the task, the individual monoliths in the respective monolith modules are to be protected from damage by thermal expansion parallel to the flow direction with fibrous mats.

Advantageously, each monolithic module, over the circumference of the same, leaving free the end faces, the inlet and outlet openings of the channels included, enclosed in one or more fibrous mat and above in a metal shell. In order to meet the corresponding thermal expansions, must with larger Modules also be laid, if necessary, several layers of fibrous mats for a layer on top of each other.

The fiber-containing mats used in the present case are sheets with two opposing large surfaces and two end faces arranged perpendicular thereto.

The fibrous mats may preferably be flattening, d. H. Inflatable mats, which expand (swell) at high temperatures. Blähmatten are usually made of silicates, z. For example, aluminum silicate, - or Aluminiumoxidsilikatfasern a Blähschiefer, z. As vermiculite, and an organic binder. Blähmatten be marketed for example by the company 3M under the trade name INTERAM®. Furthermore, 3M mats are still made of polycrystalline fibers suitable for high temperature applications.

However, the organic binders have a number of disadvantageous properties under the first temperature control up to the operating temperature, in particular they lead to the odor nuisance by evaporation of volatile components, such as for the poisoning of catalysts. Therefore, it is particularly important that the Blähmatten or fiber mats are brought quickly, preferably in a separate process step in the use state. In particular, inflatable mats are increasingly having a lower content of organic binders, from previously about 12 to 14 wt .-%, to now about 2 to 5 wt .-%, in particular 3 to 4 wt .-% organic binder, based on the Total weight of the inflatable mat, required. Due to the lower content of organic binder, the Blähmatten be crumbly, but less consistent plastically deformable in the consistency and less manageable and difficult to process during cold processing. In addition, the lateral scanning of the mats between the monoliths is added to the rectangular scanning.

By the Blähmatten are enveloped on all sides with a plastic film and the interior is vacuumed, these disadvantages are resolved and also mats with the required lower binder contents and otherwise crumbly consistency can be handled in a simple manner and in the cavities, filling the same, introduced.

The metal shell is advantageously formed from a material which is mechanically and chemically stable at the high temperature of the reaction temperature, often in the range of about 400 to 700 ° C, and has no catalytic activity for the heterogeneously catalyzed gas phase reaction, that is no reaction initiated with the reaction gas. The metal shell is preferably formed of a material which has a low coefficient of thermal expansion and is heat-resistant.

For selective gas-phase reactions on monolith catalysts encased in metal housings, however, it is preferable to use materials made of stainless steel with the material numbers 1 .4541, 1 .4919 or 1.4841. To give the monolith module a better cohesion, the respective opposite sides are stiffened with thin rods or the like.

Preferably, two or more monolith modules are grouped together to form planar packing units, which are arranged radially in the outer annular space of the reactor and extend over the entire height thereof. A packing unit thus has the shape of a flat cuboid whose length corresponds to the height of the outer annular space whose width corresponds to the radial extent of the outer annular space and whose thickness corresponds to the extent of a single monolith in the direction of the channels thereof.

One, two or more packing units each fill a segment in the outer annulus of the reactor and form a catalytically active zone.

Advantageously, spacers may be provided between each two successive flat packing units.

Two or more flat packing units are advantageously each inserted into preferably U-shaped guide rails, and thus can be exchanged in a simple manner by removing the corresponding upper and / or lower cover of the outer annular space.

Preferably, in the flow direction of the reaction mixture before each catalytically active zone in each case a supply line for an additional gas and a mixing device is provided.

Alternatively, the internals containing the heterogeneous catalyst may be formed as screen baskets filled with particulate heterogeneous catalyst.

In addition to the internals containing the heterogeneous catalyst, depending on the course of the reaction, suitable sites, bays for receiving inert material and / or heat exchange devices can be provided in the outer annulus.

Through the reactor jacket can be, in a simple manner, at any required location, facilities for measuring sensors and analysis in the outer annulus introduce and monitor the reaction processes precisely, in a simple manner.

In particular, measuring elements for determining temperatures and / or concentrations, which are introduced into the outer annular space from outside the reactor, can be provided between each two packing units.

The reactor can be easily isolated from the inside with respect to the central interior and from the outside by its simple form.

Preferably, the outer annulus, both to the reactor shell and to the central interior, provided with a thermal insulation. The thermal insulation can be carried out in one or more layers, preferably the thermal insulation which faces the outer annular space, namely both the thermal insulation applied to the inner wall of the reactor jacket and the inner cylinder, is formed from a microporous material. In addition, a further layer can preferably be provided, which isolates to the outside in the reactor jacket, as well as a layer which insulates the inner cylinder toward the central inner space. For this purpose, for example, rock wool can be used. Due to the thermal insulation of the outer annulus, the wall temperature of both cylinders defining the same, i.e., the both the reactor shell and the inner cylinder, reduced, so that this smaller wall thicknesses are required for the same strength. In particular, due to the smaller wall thickness, the thermal inertia of the cylinder bounding the outer annular space is lower, so that a faster switching between process sections with different temperature levels, as occur, for example, in autothermal gas phase dehydrogenations, for example in butane dehydrogenation, are advantageous.

The microporous insulation material may be mounted in cassettes, for example; The individual cassettes are assembled and gas-tight sealed by a thin sheet against the outer annulus, so that the hot reaction gases are not to the two, the outer annulus limiting cylinder, d. H. the reactor jacket and the inner cylinder, can pass.

The arranged in the central interior heat exchanger is in a preferred embodiment, a plate heat exchanger.

In a further preferred embodiment, the heat exchanger arranged in the central interior is a tube bundle heat exchanger. The shell-and-tube heat exchanger is arranged in the central interior, preferably in such a way that it does not assume its entire height, but that Above and below the tubesheets, in which the tubes of the tube bundle heat exchanger are welded, each free cylindrical spaces, the type of hoods, remain free.

Preferably, the reactant stream to be heated is introduced into the shell space of the tube bundle heat exchanger and flows through it from bottom to top, in cross-countercurrent to a heat carrier, which is passed through the tubes of the tube bundle heat exchanger from top to bottom. The hot product gas mixture is preferably used as the heat carrier.

In a further preferred embodiment, the cylindrical reactor shell is integrated in a pressure-bearing cylindrical housing, wherein a gap is preferably provided between the cylindrical reactor shell and the pressure-bearing cylindrical housing. The thus an outer housing, which encloses the actual reactor, the cylindrical pressure-bearing housing can be made with a smaller wall thickness. This is particularly advantageous in a reaction regime in which capacitive influences play a role, for example in autothermal gas phase dehydrogenations, which comprise process steps at different temperature levels. By the outer, pressure-bearing cylindrical shell can be designed with lower wall thickness and yet meets the required strength values, their thermal inertia is lower, which leads to corresponding advantages, in particular time saving, in a process management with different temperature levels.

The space between the reactor shell and the outer pressure-bearing housing is preferably purged with an inert gas, in particular with nitrogen or water vapor.

The invention also relates to the use of the reactor described above for carrying out endothermic, exothermic or adiabatic, heterogeneously catalyzed gas phase reactions. The reactions may be preferably dehydrogenations, in particular autothermal gas phase dehydrogenations, preferably of n-butane, isobutane, n-propane, butene or ethylbenzene, or else oxidations, in particular to acrolein, methacrolein, acrylic acid, methacrylic acid, phthalic anhydride or maleic anhydride or hydrogenations, in particular of maleic anhydride to Tetra hydrofu ran.

The inventive arrangement of a heat exchanger in the central interior of the reactor, a preheating of the reactants with high efficiency is possible, in particular by indirect heat exchange with the product gas mixture, whereby a heat recovery is ensured. The temperature level generated by the heat of reaction in the outer annulus leads to much higher temperatures in the central interior space than outside the reactor. By arranging the heat exchanger in the central interior according to the invention, the heat losses during the heat transfer from the product gas mixture to the educt current are significantly lower compared to a conventional arrangement. In addition, heat losses via connecting lines, which would be required for an external heat exchanger.

The same reference numerals designate identical or corresponding components to the figures.

They show in detail:

1 shows a longitudinal section through a preferred

Embodiment of a reactor R according to the invention;

Figure 2 is a longitudinal section through a further preferred

Embodiment of a reactor R according to the invention;

3 shows a cross section through a further preferred

Embodiment of a reactor R according to the invention, with a longitudinal sectional view in the plane B-B in Figure 4;

Figure 3A shows a cross section through an advantageous

Embodiment of the reactor R shown in Figure 3;

FIG. 4, see above;

Figure 5 is a cross-section through a further preferred

Embodiment of a reactor R according to the invention, with a further advantageous embodiment in Figure 5A;

FIG. 5A, see above;

Figures 6A and 6B are longitudinal sectional views through the reactor shown in Figure 5, in the plane B-B (in Figure 6A) and with illustration A-A '(in Figure 6B);

Figures 7A and 7B are longitudinal sectional views through a further preferred

Embodiment of a reactor R according to the invention, with supply of fuel gas. Figure 1 shows a section in the plane AA 'by a preferred embodiment of a reactor according to the invention R, with a cylindrical reactor shell RM and a concentric inner cylinder I, the reactor interior in an outer annulus RR and a central interior IR split, wherein in the sectional view in Figure 1 from the outer annulus RR the entry segment ES and the exit segment AS are visible.

Via a thermally compensated supply line 1, a gaseous reactant stream is introduced through the inlet segment ES into the jacket space of the heat exchanger W arranged in the central interior IR, flows through it around the tubes, is deflected by baffles, and finally leaves the heat exchanger W at the upper end thereof an opening in the inlet segment ES of the outer annular space RR, to be guided from here to the non-representable in the figure internals containing the heterogeneous catalyst.

The product gas mixture leaves the outer annular space RR via the outlet segment AS, via an opening in the upper region thereof, and enters into the hood above the heat exchanger W in the central interior IR, flows into the tubes of the heat exchanger W, heated by indirect heat exchange the educt current and finally leaves the heat exchanger W via the lower hood in the central interior IR and the thermally compensated discharge line 2 through the exit segment AS.

As can be seen from the figure, the upper and the lower cover of the central inner space IR are advantageously detachable, so that accessibility to the heat exchanger W, for example for maintenance purposes, is ensured.

Figure 2 shows a section in the plane A-A 'by another embodiment of the reactor R shown in longitudinal section in Figure 1, wherein the reactor on all sides has a thermal insulation IS to reduce heat loss.

FIG. 3 shows a cross section through the preferred embodiment of a reactor R according to the invention shown in FIG. 2, with a cylindrical reactor jacket RM and a concentric inner cylinder I which divide the reactor interior into an outer annular space RR and a central inner space IR, wherein outer annular space RR internals are provided, which are formed in the preferred embodiment shown in the figure as monoliths M, wherein in the radial direction by way of example six monoliths are arranged.

As can be seen from the longitudinal section in FIG. 4 (section BB), several rows of monoliths M are stacked one above the other in each case for a monolith module MM and by way of example, 7 monolith modules MM are stacked on top of each other, forming a flat packing unit P in each case.

Via a supply line 1, a gaseous reactant stream is first introduced into the shell space of the heat exchanger W in the central interior IR and then flows into the inlet segment ES of the outer annulus RR is equalized via the flow rectifier G and flows through the arranged in the outer annulus RR internals, the contain heterogeneous catalyst, and which are formed in the preferred embodiment shown in Figure as monoliths M, which are summarized to monolith modules MM. The monolith modules MM are inserted into guide rails F, which are arranged on the walls of the reactor jacket RM and of the inner cylinder I facing the outer annular space RR.

The reaction gas mixture flows through the complete outer annular space RR, which in the preferred embodiment shown in FIG. 3 comprises three catalytically active zones Z, flows through an opening in the upper region as exit segment AS into the upper hood space, flows through the tubes from top to bottom into the lower hood space Dome space and leaves the same via the discharge line 2 through the exit segment AS, which, in the preferred embodiment shown in the figure by a partition T is separated from the inlet segment.

Additional feed gas is fed via three feed lines 3, whereby after each feed line 3 a mixing device EV is arranged in each case.

FIG. 3A shows a cross section through a further improved embodiment of the reactor R shown in FIG. 3, wherein additionally a fuel gas feed line BG is provided in the entry segment ES.

FIG. 4 shows a longitudinal section B-B through the preferred embodiment of a reactor R according to the invention shown in cross-section in FIG. 3. The section B-B is laid through monolith modules MM and illustrates their expansion in the longitudinal direction of the reactor, forming a flat packing unit P.

FIG. 5 shows a longitudinal section through a further improved embodiment of the reactor shown in cross-section in FIG. 3, wherein the reactor jacket RM having an insulation IS is in a pressure-bearing cylindrical jacket Housing D is wrapped, which also has an insulation IS, with a gap between the reactor jacket RM and the pressure-carrying cylindrical housing D, which is flushed by an inert gas.

FIG. 5A shows a cross section through a further improved embodiment of the reactor R shown in FIG. 5, wherein additionally a fuel gas feed line BG is provided in the inlet segment ES.

The longitudinal section in the plane BB in Figure 6A and the sectional view A-A ', wherein the section through the supply line 1, the inlet chamber ES, the outlet chamber AS and the outlet line 2 is set, illustrate the gap between the reactor shell RM and the pressure-bearing cylindrical Housing D, which, via the nozzle shown in the figures, can be purged with an inert gas.

FIGS. 7A and 7B show sectional views in the plane AA 'for the reactor R shown in cross-section in FIG. 5A, each with different embodiments for the fuel gas supply BG, this being designed as a tube with a multiplicity of openings in FIG FIG. 7B as a dip tube, followed by static mixers.

LIST OF REFERENCE NUMBERS

1 supply line for educt current

2 discharge line for product gas mixture

3 supply line for additional gas

AS exit segment

BG fuel gas supply

D pressure-bearing cylindrical housing

ES entry segment

EV mixing device

F guide rail

G flow straightener

I inner cylinder

IS thermal insulation

IR central interior

M monolith

MM monolith module

R reactor

RM reactor jacket

RR outer annulus

Flat pack unit

W heat exchanger

Z catalytically active zone

Claims

claims

1 . Cylindrical reactor (R) with vertical longitudinal axis for carrying out heterogeneously catalyzed gas phase reactions by reacting a gaseous Eduktstromes to a product gas mixture, with a cylindrical

Reactor jacket (RM) and a concentric inner cylinder (I), which divides the reactor interior into an outer annular space (RR) and a central inner space (IR),

wherein internals are provided in the outer annulus (RR) containing the heterogeneous catalyst,

with a feed line (1) for the gaseous reactant stream into an inlet segment (ES) of the outer annular space (RR) and with a discharge line (2) for the product gas mixture from an exit segment (AS) of the outer annular space (RR), wherein the entry segment (ES ) and the outlet segment (AS) are gas-tightly separated from each other,

and wherein in the central interior (I) a heat exchanger (W) is arranged, wherein the gaseous reactant stream is preheated before it is fed into the inlet segment (ES).

2. Reactor (R) according to claim 1, characterized in that the gas-tight separation of the inlet segment (ES) from the outlet segment (AS) by means of a partition wall (T) is executed.

3. Reactor (R) according to claim 1 or 2, characterized in that the gas-tight separation of the inlet segment (ES) from the outlet segment (AS) by means of a

Separating segment is carried out, can be placed through the feed lines in the central interior (IR) and / or allows the accessibility of the central interior (IR) from outside the reactor. 4. Reactor (R) according to any one of claims 1 to 3, characterized in that as internals containing the heterogeneous catalyst, monolith modules (MM) are provided which

are formed of monoliths (M) with channels arranged horizontally substantially along concentric circles, which are each arranged in two, three or more rows, one row at a time along each reactor radius, and two, three or more rows of monoliths (M) stacked on top of each other, where each monolith module (MM) over the circumference of the same, leaving free the end faces, the inlet and outlet openings of the channels contained in one or more fibrous mats and the same is enclosed in a metal shell, wherein

- Each monolith module (MM), the outer annular space (RR) in the radial direction completely fills, wherein

in each case two or more monolith modules (MM) are combined one above the other into planar packing units (P) which are arranged radially in the annular space (RR) of the reactor (R), and wherein

- One, two or more packing units (P) each fill a segment in the outer annular space (RR) of the reactor (R) over the entire height thereof and form a catalytically active zone (Z).

Reactor (R) according to one of claims 1 to 3, characterized in that as internals containing the heterogeneous catalyst, monolith modules (MM) are provided which

monoliths (M) are formed with channels arranged substantially horizontally along concentric circles, each being arranged in four or more rows, one row at a time along a reactor radius, and four or more rows of monoliths (M) being stacked on top of each other, in which

each monolith module (MM) over the circumference of the same, leaving free the end faces, the inlet and outlet openings of the channels contained in one or more fibrous mats and the same is enclosed in a metal shell, wherein

each monolith module (MM) completely fills the outer annulus (RR) in the radial direction, wherein

in each case two or more monolith modules (MM) are combined one above the other into planar packing units (P) which are arranged radially in the outer annular space (RR) of the reactor (R), and wherein

one, two or more packing units (P) in each case fill a segment in the annular space (RR) of the reactor (R) over its entire height and form a catalytically active zone (Z).

Reactor (R) according to one of claims 1 to 3, characterized in that as internals containing the heterogeneous catalyst, monolith modules (MM) are provided which monoliths (M) are formed with horizontally arranged substantially along concentric circles channels, which are each arranged to eight or more, each along a reactor radius adjacent to each other and wherein

eight or more rows of monoliths (M) are stacked on top of each other, wherein

one, two or more flat packing units (P) each fill a segment in the annular space (RR) of the reactor (R) over its entire height and form a catalytically active zone (Z).

Reactor (R) according to one of Claims 1 to 6, characterized in that the outer annular space (RR) has thermal insulation (IS) both to the reactor jacket (RM) and to the central inner space (IR).

Reactor (R) according to one of claims 4 to 7, characterized in that spacers are provided between each two successive flat packing units (P).

Reactor (R) according to one of claims 4 to 8, characterized in that d one, two or more flat packing units (P) each guide rails (E) are inserted.

10. Reactor (R) according to one of claims 4 to 9, characterized in that in the flow direction of the reaction gas mixture before each catalytically active zone (Z) each have a feed line (3) for an additional gas and a mixing device (EV) is provided.

1 1. Reactor (R) according to one of claims 1 to 3, characterized in that the internals are designed as screen baskets which are filled with a particulate, heterogeneous catalyst.

12. Reactor (R) according to any one of claims 1 to 1 1, characterized in that in the outer annular space (RR) in addition to the internals containing the heterogeneous catalyst, bays are provided for receiving inert material and / or heat exchanger devices.

13. Reactor (R) according to any one of claims 4 to 12, characterized in that between each two packing units (P) measuring elements for the determination of temperatures and / or concentrations are provided, via the cylindrical reactor jacket (RM) from outside the reactor ( R) in the outer

Annular space (RR) are introduced.

14. Reactor (R) according to any one of claims 1 to 13, characterized in that the heat exchanger (W) is a tube bundle heat exchanger.

15. Reactor (R) according to any one of claims 1 to 13, characterized in that the heat exchanger (W) is a plate heat exchanger.

16. Reactor (R) according to one of claims 1 to 15, characterized in that the cylindrical reactor jacket (RM) in a pressure-bearing cylindrical

Housing (D) is integrated, wherein preferably between the cylindrical reactor jacket (RM) and the pressure-bearing cylindrical housing (D), a gap is provided, which preferably has an inert gas purging.

17. Use of the reactor (R) according to any one of claims 1 to 16 for carrying out endothermic, exothermic or adiabatic reactions.

18. Use according to claim 17, characterized in that the reactions are dehydrogenations, in particular autothermal gas phase dehydrogenations, preferably of n-butane, isobutane, n-propane, butene or ethylbenzene, oxidations, in particular to acrolein, methacrolein, acrylic acid, methacrylic acid, phthalic anhydride or Maleic anhydride or hydrogenations, in particular of maleic anhydride to tetrahydrofuran.