HK1059593B - Process and device for carrying out reactions in a reactor with slot-shaped reaction spaces - Google Patents

Description

Process and apparatus for carrying out reactions in a reactor having a trough-shaped reaction space

Technical Field

The invention relates to a process for carrying out a reaction between at least two fluid reactants using a reactor with internal wall elements, a channel-shaped reaction space and an internal space for the passage of a fluid heat carrier.

Background

From DE3342749a1, a plate reactor for chemical synthesis at high pressure is known, in which the plates are in the form of flat right parallelepipeds and are bounded by sheet metal walls, respectively forming chambers filled with catalyst, wherein the largest two walls of the chambers are gas-tight. The reaction gas flows horizontally or vertically through the granular catalyst, passing through the narrow sides of two openings or perforations of a right parallelepiped disposed opposite each other. In view of heating or cooling (exothermic or endothermic depending on the reaction), cooling channels are provided in the chamber for circulating the liquid heat carrier. These cooling channels may be formed by sheet metal members in the form of webs, corrugated metal sheets or the like, which are firmly connected to the smooth wall, for example by welding. The overall profile of the chamber accommodates the shape of the cylindrical reactor, so that a portion of the chamber changes size and is continuously filled with reactive gas, for example in groups. The structural design is very elaborate and the already low production can be increased at best by axial lengthening and/or parallel connection of a plurality of reactors.

From EP0691701a 1a stacked reforming generator is known, in which, taking into account the endothermic reactions taking place, in each case a reforming chamber, to which a heat recovery member is connected downstream, is embedded between two combustion chambers. In this case, the gas flow directions in the reforming chamber and in the combustion chamber are opposite, the semi-permeable wall being located before the heat recovery chamber, which is connected downstream in each case. For example, the heat recovery member is constituted by alumina balls. In view of improving the heat exchange, between the individual chambers are arranged horizontal heat-conducting laminas provided with openings for the passage of fuel in the heating zone. Between each of these triads, a fuel distribution chamber is provided. Said device is structurally very complex and neither satisfactory nor adaptable to exothermic reactions, since it does not have cooling channels, which goes against the meaning and purpose of said known solutions. The structural design is not suitable for operation at high pressure, for the purpose of shortening the overall length by omitting special heating zones.

From DE4444364C2, a vertical fixed bed reactor with a rectangular shell cross section is known for exothermic reactions between gases, wherein the fixed bed consisting of catalyst is vertically divided for the purpose of forming separate flow channels and plate heat exchangers. Below and above the flow channels, catalyst-free spaces are provided in each case in an alternating arrangement. The gas is discharged from some of the flow channels at the upper end of the fixed bed and is supplied to the gas outlet nozzles via the respective other flow channels again through the transverse overflow channels below the fixed bed. The device is neither satisfactory nor adaptable to endothermic reactions, since it does not have any means for supplying heat. Furthermore, due to the rectangular cross-section of the housing, the structural design is not suitable for operation at high pressures.

From EP0754492a2, a plate reactor for the reaction of fluid components is known, which is constructed in the form of a static mixer with heat exchange. For this purpose, a plurality of plates are stacked one above the other, the lowermost being closed in the outward direction and the uppermost being perforated only in the outward direction for feeding and discharging the components to be reacted or already reacted and the heat carrier component. Furthermore, the respective second plates below and above have grooves which are open on one side for changing the direction of the reactants through the stack in a meandering shape. In the plate located therebetween, there are provided an X-shaped or clover-shaped mixing chamber and a reaction chamber, which are connected to each other in the stacking direction. The heat exchanger channels also pass through the stacked plates in a curved shape. The plates are made of a material with good thermal conductivity, preferably metals and alloys, with a thickness between 0.25 and 25mm and can be made by micro-machining, etching, stamping, lithographic processes, etc. They are firmly and tightly joined to each other on the outside surface of the hole, i.e., on the outer periphery, by clamping, bolts, rivets, brazing, adhesive bonding, etc., thereby forming a laminate. The complex flow path creates a great resistance to the flowing fluid and cannot be filled with catalyst. Due to the necessary machining, the production process is very fine, since all contact surfaces have to be finely ground.

From DE19754185C1, a reactor for the catalytic conversion of fluid reaction elements is known, in which a fixed bed is composed of catalytic material supported on a sieve plate and subdivided by vertical heat fins, which are each composed of two metal sheets in the shape of cushions that have been repeatedly deformed and which are welded to one another, containing spaces for the passage of cooling or heating elements at locations distributed in the form of grids. The reaction part and the heat carrier part pass through the fixed bed column between the hot plates on the one hand and the inner cavity of the hot plates on the other hand in a countercurrent mode. The vessel of the reactor is constructed in the form of a vertical cylinder and the heat fins are adapted to the cylinder, i.e. they have changed size. Moreover, in this case, the production can be increased at best by axial lengthening and/or parallel connection of a plurality of reactors.

From DE19816296a1 by the same applicant it is known to produce an aqueous hydrogen peroxide solution from water, hydrogen and oxygen in a reactor which may be packed with fixed bed packing of particulate catalyst and planar monolithic supports provided with channels, in the form of heat exchangers, and with a coating of catalytic material. As catalysts, there are defined elements of sub-group 8 and/or 1 of the periodic Table of the elements, such as Ru, Rh, Pd, Ir, Pt and Au, with Pd and Pt being particularly preferred. As support materials, water-insoluble oxides, mixed oxides, sulfates, phosphates and silicates of activated carbon, alkaline earth metals, Al, Si, Sn and metals belonging to the 3 rd to 6 th sub-groups are defined. Oxides of silicon, aluminum, tin, titanium, zirconium, niobium and tantalum, and barium sulfate are preferred. A metal or ceramic wall having a heat exchanger function similar to a plate heat exchanger is referred to as the material of the monolithic carrier. The particular test reactor had an internal diameter of 18mm and a length of 400 mm. The temperature is in the range of 0 to 90 deg.C, preferably 20 to 70 deg.C, and the pressure is between atmospheric pressure and about 10MPa, preferably between about 0.5 and 5 MPa. Moreover, for the case of this prior art, the production can at best be increased by axial lengthening and/or parallel connection of a plurality of reactors.

The reactors according to DE19544985C1 and DE19753720a1 comprise plate-shaped heat exchangers in which a fluid heat carrier is passed through a channel formed between two plates. There is no suggestion of the function of the wide channel-shaped reaction space.

The device according to DE19741645A1 comprises a microreactor having reaction and cooling channels, wherein the depth of the reaction channels is less than 1000 μm and the minimum wall thickness b between the reaction and cooling channels is less than 1000. mu.m. This document gives no teaching about the use of reaction spaces outside the channels. DE19748481 refers to microreactors comprising a plurality of parallel channels as reaction spaces. Large volume reactors are expensive to manufacture.

Furthermore, so-called microreactors are known, in which the size of the flow channels is in the range of hundreds of micrometers (typically < 100 μm). This results in higher transport values (heat and mass transfer parameters). The fine passage serves as a fire barrier so that the explosion does not spread. Furthermore, in the case of toxic reactants, small reserves (hold-up volumes) lead to an inherently safe reactor. However, due to the small size, it is not possible to fill the channels with catalyst. Another important disadvantage is the elaborate production process. In order to prevent the clogging of the fine channels, it is necessary, in addition, to provide suitable filter protection upstream of the reactor. High throughputs can only be achieved by parallel connection of a plurality of such reactors. Furthermore, the reactor can only be operated at high pressures when the cooling means are at the same pressure level.

Disclosure of Invention

The object of the present invention is to provide a process and an apparatus which allow an endothermic and exothermic process to be carried out at will, wherein a plurality of fluid reactants are reacted with each other in the presence or absence of a catalyst, and the reaction zones of the reactor are constructed in a modular design, so that the production volume can be adapted to the requirements.

According to the invention, the object is achieved in the process described at the outset in that:

a) in each case, the channel-shaped reaction space is formed between the sides of two substantially right parallelepiped wall elements which are substantially equally large and are formed by solid plates, and which are interchangeably arranged in a substantially right parallelepiped module;

b) the reactants are introduced into the channel-shaped reaction space from the edge region on the same side of the module and pass through the reaction space in a similar direction as a reaction mixture in parallel flows; and

c) the fluid heat carrier passes through an inner cavity extending inside said wall elements.

In one aspect, the invention proposes a process for carrying out a reaction between at least two fluid reactants using a reactor in which wall elements, channel-shaped reaction spaces and an inner chamber for the passage of a fluid heat carrier are provided, characterized in that:

a) in each case, the channel-shaped reaction space is formed between the sides of two substantially right parallelepiped wall elements which are substantially equally large and are formed by solid plates, and which are interchangeably arranged in modules within a substantially right parallelepiped;

b) the reactants are introduced into the channel-shaped reaction space from the edge region on the same side of the module and pass through the reaction space in a similar direction as a reaction mixture in parallel flows;

c) said fluid heat carrier passing through a tubular lumen extending inside said wall elements; and

d) the reaction space is closed on the narrow sides of the wall elements extending parallel to the flow direction of the reactants by plates provided with openings for feeding and discharging the heat carrier into and from the wall elements;

wherein the slot width of the reaction space is between 0.05 and 5 mm.

In another aspect, the invention proposes a device for carrying out a reaction between at least two fluid reactants using a reactor in which wall elements, a reaction space and an internal cavity for the passage of a fluid heat carrier are provided, characterized in that:

a) in each case, the reaction space is channel-shaped and located between the sides of two substantially right parallelepiped wall elements, substantially equally large and formed by solid plates, and which are interchangeably arranged in modules within a substantially right parallelepiped;

b) reactants can be supplied to the channel-shaped reaction space from the same side of the module and the reaction mixture can be passed through the reaction space in parallel flows in a similar direction;

c) said wall elements having tubular cavities for the passage of a fluid heat carrier through said wall elements; and

d) the reaction space is closed on the narrow sides of the wall elements extending parallel to the flow direction of the reactants by plates provided with openings for feeding and discharging the heat carrier into and from the wall elements;

wherein the slot width of the reaction space is between 0.05 and 5 mm.

Drawings

Fig. 1 is a perspective exploded view of a set of two wall elements.

Fig. 2 is a schematic perspective view of a series arrangement of a number of the wall elements of fig. 1.

Fig. 3 is a vertical sectional view of the series arrangement of fig. 2 above the bottom of the pressure-resistant reactor.

Fig. 4 is an enlarged detail view of circle a in fig. 3 supplemented in perspective.

Fig. 5 is a partial vertical side sectional view of the subject matter of fig. 3 after being rotated approximately 90 degrees.

Fig. 6 is the subject matter of fig. 2, schematically supplemented with distribution spaces and collection spaces for educts and products.

Fig. 7 is a vertical cross-sectional view of a plate and a distributing body with fluid channels for reactants and/or a heat carrier.

FIG. 8 is a partial vertical sectional view through a first embodiment of a reactor having a pressure vessel.

Fig. 9 is a bottom view of the lid of the pressure vessel of fig. 8.

FIG. 10 is a partial vertical sectional view through a second embodiment of a reactor having a pressure vessel.

Detailed Description

According to the invention, the stated objects are achieved in all cases, in particular in that the endothermic and exothermic processes can be carried out at will, with or without a catalyst, with a plurality of fluid reactants (gases and/or liquids) reacting with one another, and the reaction zones of the reactor are constructed in a modular design, with the result that the production can be adapted to the requirements. By reducing the width of the reaction space, for example from 5mm to 0.05mm, the specific gravity of the area and volume of the reaction space increases. As a result, problems caused by limited heat transfer within the gas are reduced, so that highly endothermic or exothermic reactions can be safely accomplished.

However, there are other advantages:

the advantages of simple manufacture of the micro-reaction technology and the traditional factory technology are combined;

easy replacement of individual wall elements (the term "substantially equal and substantially right parallelepiped" means that the minimum deviation due to constraints (constraints) is allowable);

the thickness of the wall elements is practically arbitrary without affecting the function;

the specific surface area is increased by profiling/coarsening;

forming the side surface into a full or partial coating of varying catalytic material by dipping, spraying, printing, etc. of varying thickness;

filling the reaction space with catalyst particles of varying size;

the possibility of gas/gas reactions, gas/liquid reactions and liquid/liquid reactions;

flow patterns and fluidic channel effects, e.g. for drainage and for outflow of liquid reaction products, simple separation;

the possibility of varying the slot width;

the reactants are only mixed in the reaction space, and the reaction is well controlled;

backflow from the reaction space is avoided;

good controllability due to high heat transfer coefficient and large surface, i.e. fast response to changes in load and/or required temperature values and uniform temperature profile, thereby extending the service life of the catalyst by avoiding "hot spots";

safety inherent in reacting other explosive reaction mixtures;

smaller dead volume ("hold up volume");

the possibility of working at high pressure, the pressure loss in the reaction space is small;

tightness of the liquid volume and operability of the tank, which allows the temperature to be controlled from the outside and allows the reaction to be terminated slowly by "quenching" and/or flushing;

to prevent secondary reactions, inhibitors can be added, ensuring the reducibility of the gas/liquid volume by filling the pressure vessel on the other side of the product outlet of the tank with materials and/or displacing agents;

the number of joints is reduced and sealing is easier for leaks (important in the case of toxic components);

the small resistance to diffusion, the high space-time yield, in particular higher yields than in known microreactors, simplifies the "scale up" from laboratory scale to production scale by multiplication ("number increase");

the simple and compact structural design reduces the investment cost and the operation cost (maintenance and energy consumption);

possibility of small factory building.

In this respect, within the scope of a further configuration of the process according to the invention, it is particularly advantageous if the following conditions-individually or in combination-are satisfied:

supplying at least one reactant through said wall elements and introducing the reactant into said reaction space through at least one side of said wall elements;

distribution means on at least one side of the module for providing reactants to the reaction space from the distribution means,

as a distribution part, a solid body with a plurality of sets of channels is used, the channel cross-section being chosen to be small so that the flame cannot spread when reactants forming an explosive mixture are supplied;

as the distribution member, a filler material is used whose particle size and gap are selected to be small so that the flame is unlikely to spread when the reactants forming the explosive mixture are supplied;

preferably, the slot width of the reaction space is between 0.05 and 5mm, more preferably 0.05 to 0.2mm；

In the case of explosive reaction mixtures, the width of the slot is small, so that flame propagation is not possible;

filling a reaction space with a granular catalyst;

the sides of the wall elements facing the reaction space are covered with catalyst material at least in places;

the side surface of the wall element facing the reaction space is provided with a forming structure for increasing the surface area;

said wall elements being at least partially immersed in water or an organic solvent or a mixture of solvents;

as solvent, water is used, optionally with at least an inhibitor to prevent decomposition and/or degradation of the reaction product; and/or, if

The process is used to produce hydrogen peroxide from water (steam), hydrogen and air, which may be oxygen-enriched, or oxygen.

The invention also relates to a device for carrying out a reaction between at least two fluid reactants using a reactor, wherein wall elements, channel-shaped reaction spaces and an inner space for the passage of a fluid heat carrier are provided in the reactor.

In view of the above object, according to the present invention, such a device is characterized in that:

a) in each case, the channel-shaped reaction space is formed between the sides of two substantially right parallelepiped wall elements which are substantially equally large and are formed by solid plates, and which are interchangeably arranged in modules within a substantially right parallelepiped;

b) the reactants are introduced into the channel-shaped reaction space from the same side of the module and the reaction mixture passes through the reaction space in a parallel flow in a similar direction; and

c) the wall elements each have a tubular inner cavity for the passage of the fluid heat carrier through the wall elements.

The process and the apparatus are suitable for the following processes (examples):

selective hydrogenation and oxidation;

acrolein is produced, for example, by subjecting propylene to catalytic oxidation with an oxygen-containing gas having an increased oxygen content compared with air, in the presence of a catalyst containing Mo at a temperature of 350 to 500 ℃, under a pressure of o.1 to 5Mpa, with an increase in selectivity;

for example, acrylic acid is produced by catalytic oxidation of propylene in the presence of a Mo-containing catalyst and a promoter at 250 to 350 ℃ and O.1 to 0.5 MPa;

ethylene oxide or propylene oxide is produced from ethylene or propylene and gaseous hydrogen peroxide, respectively, in the presence of an oxidizing or siliceous catalyst, such as titanium silicate, at a temperature of 60 to 200 ℃ and at a pressure of O.1 to 0.5MPa,

from H in the presence of a noble metal catalyst and water or steam₂And O₂Or direct synthesis of hydrogen peroxide from oxygen-containing gases, for example according to the processes disclosed in DE-A19816296 and according to those disclosed in the other documents cited herein. As catalysts in this respect, elements from sub-group 8 and/or 1 of the periodic Table of the elements, such as Ru, Rh, Pd, Ir, Pt and Au, are used, with Pd and Pt being particularly preferred. The catalysts themselves may take the form of, for example, suspended catalysts, or supported catalysts as packing in a channel space, or they may be fixed to the wall elements directly or via an intermediate forming a layer of support material. As the support material, activated carbon, alkaline earth metal, Al, Si, Sn, and water-insoluble oxides, mixed oxides, sulfates, phosphates, and silicates of metals belonging to the 3 rd to 6 th sub-groups are used. Oxides of silicon, aluminum, tin, titanium, zirconium, niobium and tantalum, and barium sulfate are preferred. In the case of the direct synthesis of hydrogen peroxide, the reaction temperature is, for example, within the range from 0 to 90 deg.C, preferably from 20 to 70 deg.C, and the pressure is between atmospheric pressure and about 10MPa, preferably between 0.5 and 5 MPa.

In this respect, within the scope of a further configuration of the device according to the invention, it is particularly advantageous if the following conditions, individually or in combination, are satisfied:

at the wall elements, in each case at least one transfer channel is provided which opens into the reaction space via one of the at least one side faces of the wall elements;

a distribution member is provided on at least one side of the module, and reactants are provided to the reaction space through the distribution member;

the distribution member is a solid body with a plurality of sets of channels, the channel cross-section being chosen small so that flame propagation is not possible when reactants forming an explosive mixture are supplied;

the distribution member is a filler material with particle size and gap selected to be small so that flame propagation is not possible when reactants forming an explosive mixture are supplied;

preferably, the slot width of the reaction space is between 0.05 and 5mm, more preferably 0.05 to 0.2 mm;

the reaction space is filled with a particulate catalyst;

the sides of the wall elements facing the reaction space are covered with catalyst material at least in places;

the side surface of the wall element facing the reaction space is provided with a forming structure for increasing the surface area;

the above-mentionedThe wall element is partially or completely housed in the container;

the reaction space is closed on the narrow sides of the wall elements extending parallel to the flow direction of the reactants by plates provided with openings for feeding and discharging the heat carrier into and from the wall elements;

further openings are provided in the plate for feeding at least one of the reactants into the wall elements, and the wall elements are each provided with at least one conveying channel which in each case leads via a discharge opening to one of the reaction spaces;

said wall elements are each provided with a set of tubular cavities extending parallel to the sides of the wall elements and closed at their ends by plates mounted on the narrow sides of the wall elements and provided with openings for the heat carrier aligned with the cavities on the plates;

said plate being provided, on its outer side and in front of said openings, with fluid channels extending at right angles to said wall elements for at least one of said reactants and/or a heat carrier;

said plate being covered on its outer side remote from said wall elements with a distributing body provided with fluid channels, the openings in said plate opening into said channels;

the wall element is formed by two sub-elements having a semi-cylindrical or other shaped groove, so that a tubular lumen is formed by the two respective sub-elements pressed together;

the wall elements are housed in the pressure vessel in the form of modules;

the pressure vessel can be at least partially filled with a solvent;

the pressure vessel has a lid with a diaphragm that can be mounted on the dispensing part and two connecting sleeves for the delivery of two reactants;

the slot width of the reaction space can be varied by varying the thickness of the partition.

Embodiments of the subject matter of the invention are explained in more detail below on the basis of fig. 1 to 10.

In fig. 1, two wall elements 1 with sides 2 are shown in exploded view, comprising a reaction space 3 between them, through which a reactant flows in the direction of arrow 4. In each wall element there is an inner cavity 5 in the form of a through hole, parallel to said side surface 2 and ending in a narrow side surface 6 of the wall element. Another scheme is given below.

The wall element 1 is in the form of a flat right parallelepiped, the largest face of which is the side face 2. These side faces 2 may have a profiled structure as shown, i.e. they may be roughened, for example in order to increase the effective surface area. The side 2 may also have, in whole or in part, a surface deposition layer of catalyst material, but this is not separately shown in the figure. Other features are more apparent in fig. 4. Alternatively or in addition, it is also possible to arrange a particulate catalyst in the reaction space 3, which is dimensioned to the slot width "s" (fig. 4).

Fig. 2 shows the combination of thirteen wall elements 1 of the same size to form a right parallelepiped module 24; this number can be varied, wherein one of the main objects of the invention is the possibility to adapt to yield and process variations. Mass transfer in the form of a unidirectional parallel flow-here from above in the downward direction-is only indicated by arrows.

Fig. 3 shows a vertical section through the series arrangement of fig. 2 above the pressure-resistant reactor bottom 7, wherein the lower flange joint 8 is shown. Optionally with regard to cleaning, liquid solvent is supplied via line 9, residual gas is removed via line 10, the final product is removed via line 11, and the contents of the reservoir are removed via line 12.

Fig. 4 shows in perspective an additional detail on an enlarged scale of circle a in fig. 3, i.e. on both sides of the reaction space 3. The slot width "s" of the reaction space 3 is maintained at a predetermined measurement value, for example, between 0.05 and 5mm, by the partition 13. However, this range may be decreased or exceeded. In the case of highly exothermic and endothermic reactions, in particular involving explosive gas mixtures, the slot width is reduced until any flame propagation is avoided. The optimum slot width depends on the component and the type of reaction and is determined experimentally. As can be seen from fig. 4 and 6, the slot width "s" of the device of the invention is significantly smaller than the thickness of the wall elements. In the tubular wall element, an inner cavity 5 is provided, as already described, for the passage of the fluid heat carrier. Depending on the temperature control, heat may be dissipated in the case of an exothermic process or supplied in the case of an endothermic process. As heat carrier, water, oil, gas and also the product itself are used.

On said wall elements 1 there are also semi-cylindrical recesses 14, complementary to form substantially cylindrical delivery channels 15 for the first reactant. Further transport channels 16 are provided in the wall elements for at least one further reactant. The transfer channels 16 are connected to the respective reaction spaces 3 through discharge openings 17, and the discharge openings 17 open into the side faces 2 of the wall elements, so that the reactants can be mixed in the reaction spaces 3. Said cavities 5, delivery channels 15 and 16 and rows of discharge openings 17 are parallel to each other and to the side 2 of the wall element 1 and extend over its entire length-seen in the horizontal direction.

The cooling channel (tubular lumen (5)) can also be constructed in a similar manner to the feed channel 15 of fig. 4, in that each wall element 1 is divided parallel to the side face 2 into two sub-elements, on the surface of which a semi-cylindrical or otherwise shaped groove is located. As a result of the respective two corresponding sub-elements being pressed together, an inner cavity 5 is formed, through which a fluidic hot carrier can flow. The term "tubular" encompasses circular or square channels or tubes.

The slot width "s" is chosen such that in the case of an explosive reaction mixture the flame cannot spread within the reaction space 3. In special cases, it is also permissible for partial explosions to form in the reaction space, in which case it is merely structurally ensured that these explosions do not pass to adjacent reaction spaces.

In this connection it is important that the transfer channels 15 and 16 extend in the (upper) edge area of said wall elements 1 or reaction spaces 3, so that practically the entire (vertical) length of the reaction spaces 3 is available for the reaction. Further details and alternatives of the supply and removal of reactants and heat carrier will be described in more detail below on the basis of the following figures.

Fig. 5 shows a partial side sectional view of the subject of fig. 3 after a 90 degree rotation about a vertical axis. Two reactants are supplied to the system via delivery conduits 18 and 19: in the case of hydrogen peroxide production, air is supplied via the delivery conduit 18 and hydrogen is supplied via the delivery conduit 19. The transport of the fluid heat carrier through the interior 5 is described in more detail below on the basis of fig. 5: the narrow sides 6 of the wall elements 1 are closed by a mounted plate 20, which is provided with U-shaped channels 21 for connecting in each case two inner chambers 5. However, only shown on the left side of the module. The heat carrier is supplied through a transfer pipe 22 and removed through a discharge pipe 23.

For the wall elements, substantially right parallelepiped plates are used, which are sufficiently thermally conductive, preferably metallic. The wall element 1, preferably made of metal, for example stainless steel, can be constituted by a solid plate with suitable holes (inner cavity 5 and delivery channel 16) and grooves 14. Alternatively, the cavities 5 can be combined into groups at will, wherein guide means for guiding the heat carrier, such as ribs, are located in the subsequently enlarged cavity. The wall element 1 may also be formed by two plate-like sub-elements which are connected to each other in a sealed manner, for example bolted together. The only important point is that they are in some cases subjected to considerable pressure differences (up to 10Mpa or 100 bar) between the heat carrier and the reactants.

Fig. 6 shows the subject matter of fig. 2, schematically showing in bold lines a (upper) distribution space 48 with a central conveying conduit 49 for educt and a (lower) collection space 50 with a discharge tube 51 for product. One of the reactants or a mixture of reactants R1 and R2 may be supplied through the distribution space 48. In the case of a mixture, the delivery ducts 15 and 16 (in fig. 4) can be dispensed with if the partition 13 is interrupted. In the case of an explosive reaction mixture, the processes of the configurations of fig. 8 to 10 may be employed in addition to the process according to the configuration in fig. 2.

The open narrow sides 6 of the wall elements 1 can be covered by a plate combination consisting of a plate 41 and a distribution body 47, which is designed to be continuous over the width and height of all wall elements 1 and is shown on an enlarged scale in fig. 7. Fig. 7 shows a vertical section through the upper edge region of such a plate combination 41/47, with a flow channel 45 for one of the reactants and a flow channel 46 for the heat carrier. For feeding and/or discharging, openings 42 and 43 are provided in the plate 41 which are connected to the fluid channels 45 and 46 of the distributing body 47.

Fluid channels 45 and 46 extending perpendicular to the plane of the drawing are formed, for example, by slots in a distributing body 47. The slots may be formed by metal cutting, casting or forging. This provides greater stability to the shape subjected to the required pressure differential. This plate combination 41/47-with openings 42 and 43 aligned with the corresponding channels on the wall element 1-is now screwed in a sealing manner on the narrow side 6 of the wall element 1 of said module 24 by means of a gasket 54. Only some of the plurality of bolted joints 52 are shown. In this way the wall elements 1 are arranged in correspondence with the arrows 53 of fig. 6. By means of dashed lines 55 it is shown that a plurality of fluid channels 46 may also be combined to form a common fluid channel or distribution space.

Panel assembly 41/47 may also be redesigned to be suitable for forming the wall elements shown in fig. 4.

Fig. 8 now shows a schematic representation of the entire reactor in partial vertical section, for example for the production of hydrogen peroxide. A right parallelepiped block 24, made up of a plurality of wall elements 1 as shown in fig. 1 and 2, is suspended from above in a pressure vessel 25 filled with a solvent, for example water, up to a liquid level 26. The trough-shaped reaction space 3 extends parallel to the plane of the drawing.

The pressure vessel 25 has at the top a lid 28 which is divided into two chambers 30 and 31 by a partition 29, the partition 29 being mounted in a sealed manner on a distribution member 37 made of a solid body, preferably metal, with two separate sets of narrow channels 39 and 40. The channel 39 extends in a solid body from the chamber 30 to the upper end of the reaction space 3 and the channel 40 extends from the chamber 31 to the upper end of the reaction space 3. In these channels 39 and 40, the reactants cannot mix, but even if mixing occurs, the flame cannot spread in the channels 39 and 40. Mixing of the reactants takes place only in the reaction space 3, in which the flame similarly cannot spread if the reaction mixture is explosive. The explosiveness of the reaction mixture is material and reaction dependent and must be determined in certain cases.

The first reactant "R1" is supplied to the chamber 30 through the connecting sleeve 34, and the second reactant "R2" is supplied to the chamber 31 through the other connecting sleeve 35. The unwanted exhaust gases are led away as indicated by arrow 32 and the product is drawn off as indicated by arrow 33, and the storage tank can be emptied via line 12. In addition, fig. 8 shows another connection sleeve 36 for a third reactant "R3" and/or a solvent such as water. The plates 41 applied to both ends are only very schematically shown.

Fig. 9 shows a bottom view of the lid 28 of the pressure vessel 25 of fig. 8. The holes 28a are for bolting.

Fig. 10 differs from fig. 8 in that as the distribution member 38, a filling substance consisting of heat-conducting particles, such as sand, sand grains, metal shavings, metal fibres, etc., is arranged above the modules 24 of the wall element 1, which are located on a not shown screening deck. In such a distribution member 38, the reactants R1 and R2 have been mixed in a random distribution before they enter the reaction space 3. However, the distribution members form such a narrow gap, and similarly, no flame propagation with explosive consequences can occur between them.

The spatial position of the wall element 1 is arbitrary: according to the figures, they can be arranged horizontally in series, but they can also be stacked vertically. The direction of the parallel flow can also be adapted to the actual need: the parallel flows may be directed vertically from the top down as shown, but they may also be directed from the bottom up in another way. The parallel flow may also be horizontal. As a result, the module 24 with the plate 41 and the connectors can be "rotated" to various spatial positions.

List of reference numerals

1-wall element

2 side surface

3 reaction space

4 arrow head

5 inner cavity

6 narrow side

7 bottom

8 flange joint

9 pipeline

10 pipeline

11 pipeline

12 pipeline

13 separating element

14 groove

15 conveying channel

16 conveying channel

17 discharge port

18 conveying pipeline

19 conveying pipeline

20 board

21 channel

22 conveying pipeline

23 discharge pipe

24 module

25 pressure vessel

26 liquid level

27 solvent

28 cover

28a hole

29 baffle plate

30 chamber

31 chamber

32 arrow head

33 arrow head

34 connecting sleeve

35 connecting sleeve

36 connecting sleeve

37 dispensing member

38 dispensing member

39 channel

40 channels

41 plate

42 opening

43 opening

44 outside

45 fluid channel

46 fluid passage

47 distributing body

48 distribution space

49 conveying pipeline

50 collecting space

51 discharge pipe

52 threaded joint

53 arrow head

54 washer

55 line

R1 reactant

R2 reactant

R3 reactant

Width of S slot

A detail (fig. 3)

Claims (32)

1. A process for carrying out a reaction between at least two fluid reactants (R1, R2) using a reactor in which wall elements (1), channel-shaped reaction spaces (3) and an inner cavity (5) for the passage of a fluid heat carrier are provided, characterized in that:

a) in each case, the channel-shaped reaction space (3) is formed between the sides (2) of two substantially right parallelepiped wall elements (1) that are substantially equally large and formed of solid plates, and the wall elements (1) are interchangeably arranged in modules (24) that are substantially right parallelepiped;

b) the reactants (R1, R2) are introduced into the trough-shaped reaction space (3) from the edge region on the same side of the module (24) and pass through the reaction space (3) in a similar direction as a reaction mixture in parallel flows;

c) said fluid heat carrier passing through a tubular inner cavity (5) extending inside said wall element (1); and

d) the reaction space (3) is closed on the narrow sides of the wall elements extending parallel to the flow direction of the reactants by plates provided with openings for feeding the heat carrier into the wall elements (1) and for discharging it from the wall elements (1);

wherein the slot width(s) of the reaction space (3) is between 0.05 and 5 mm.

2. Process according to claim 1, characterized in that at least one reactant is supplied through the wall elements (1) and the reactant is introduced into the reaction space (3) through at least one side (2) of the wall elements (1).

3. Process according to claim 1, characterized in that on at least one side of the module (24) there is provided a distribution member (37, 38) from which the reaction space (3) is supplied with reactants (R1, R2).

4. A process according to claim 3, characterised in that as the distribution member (37) a solid body is used having a plurality of sets of channels (39, 40), the cross-section of the channels being chosen small so that the flame cannot spread when reactants (R1, R2) forming an explosive mixture are supplied.

5. A process according to claim 3, characterized in that as distributing member (38) a filling material is used, the particle size and the gap of which are chosen to be small so that the flame cannot spread when reactants (R1, R2) forming an explosive mixture are supplied.

6. The process as claimed in claim 1, characterized in that the slot width(s) of the reaction space is selected to be so small that no flame propagation occurs in the case of explosive reaction mixtures.

7. The process as claimed in claim 1, characterized in that the reaction space (3) is filled with a particulate catalyst.

8. Process according to claim 1, characterized in that the sides (2) of the wall elements (1) facing the reaction space (3) are covered with catalyst material at least in places.

9. Process according to claim 1, characterized in that the side (2) of the wall elements (1) facing the reaction space (3) is provided with a profiled structure for increasing the surface area.

10. Process according to claim 1, characterized in that said wall elements (1) are at least partially immersed in a solvent (27).

11. The process as claimed in claim 10, wherein the solvent (27) is water.

12. The process as claimed in claim 10, characterized in that at least one stabilizing additive for preventing decomposition or degradation of the reaction products is added to the solvent (27).

13. Process according to one of claims 1 to 12, for the direct synthesis of hydrogen peroxide from hydrogen and oxygen or oxygen-containing gas in the presence of a catalyst comprising at least one element of transition group 8 and/or 1 of the periodic table of the elements and water or water vapor.

14. The process according to any one of claims 1 to 12, for producing acrolein from propylene and an oxygen-containing gas in the presence of a catalyst.

15. The process according to any one of claims 1 to 12, for producing acrylic acid from propylene and an oxygen-containing gas in the presence of a catalyst and a promoter.

16. The process as claimed in any one of claims 1 to 12, for producing ethylene oxide or propylene oxide from ethylene or propylene and gaseous hydrogen peroxide, respectively, in the presence of an oxidative or siliceous catalyst.

17. Device for carrying out a reaction between at least two fluid reactants (R1, R2) using a reactor in which wall elements (1), a reaction space (3) and an inner cavity (5) for the passage of a fluid heat carrier are provided, characterized in that:

a) in each case, the reaction space (3) is trough-shaped and located between the sides (2) of two substantially right parallelepiped wall elements (1) that are substantially equally large and formed of solid plates, and the wall elements (1) are interchangeably arranged in modules (24) that are substantially right parallelepiped;

b) reactants can be supplied to the channel-shaped reaction space (3) from the same side of the module (24) and the reaction mixture can be passed through the reaction space (3) in a parallel flow in a similar direction;

c) said wall element (1) having a tubular inner cavity (5) for the passage of a fluid heat carrier through said wall element (1); and

d) the reaction space (3) is closed on the narrow sides of the wall elements extending parallel to the flow direction of the reactants by plates provided with openings for feeding the heat carrier into the wall elements (1) and for discharging it from the wall elements (1);

wherein the slot width(s) of the reaction space (3) is between 0.05 and 5 mm.

18. Device as claimed in claim 17, characterized in that at least one supply channel (16) for at least one reactant is provided in each case on the wall elements (1), which supply channel opens into the reaction space (3) via at least one side (2) of the wall elements (1).

19. The apparatus as claimed in claim 17, characterized in that distribution means (37, 38) are provided on at least one side of the module (24), from which distribution means reactants (R1, R2) are supplied to the reaction space (3).

20. Device according to claim 19, characterized in that the distribution member (37) is a solid body with a plurality of sets of channels (39, 40), the cross-section of which is chosen to be small so that the flame cannot spread when reactants (R1, R2) forming an explosive mixture are supplied.

21. The apparatus as claimed in claim 19, characterized in that the distribution member (38) is a filling material whose particle size and gap are chosen to be small so that flame propagation is not possible when reactants (R1, R2) forming an explosive mixture are supplied.

22. The apparatus as claimed in claim 17, characterized in that the reaction space (3) is filled with a particulate catalyst.

23. Device according to claim 17, characterized in that the side (2) of the wall elements (1) facing the reaction space (3) is covered with catalyst material at least in places.

24. Device according to claim 17, characterized in that the side (2) of the wall elements (1) facing the reaction space (3) is provided with a profiled structure for increasing the surface area.

25. The device according to claim 17, characterized in that the reaction space (3) is closed on the narrow sides (6) of the wall elements (1) extending parallel to the flow direction of the reactants (R1, R2) by plates (41) provided with openings (43) for feeding heat carrier into the wall elements (1) and for discharging it from the wall elements (1).

26. Device according to claim 25, characterised in that further openings (42) for feeding at least one reactant (R1, R2) into the wall elements (1) are provided in the plate (41), and that the wall elements (1) are each provided with at least one conveying channel (16) which leads in each case via a discharge opening (17) to one of the reaction spaces (3).

27. Device according to claim 25, characterised in that the wall elements (1) are each provided with a set of tubular cavities (5) extending parallel to the sides (2) of the wall elements (1) and closed at their ends by plates (41) mounted on the narrow sides (6) of the wall elements (1) and provided with openings (43) for a heat carrier aligned with the cavities (5).

28. Device according to claim 25 or 26, characterized in that said plate (41) is provided, on its outer side (44) and in front of said openings (42, 43), with fluid channels (45, 46) extending at right angles to said wall elements (1) for at least one of said reactants (R1, R2) and/or a heat carrier.

29. Device according to claim 28, characterised in that the plate (41) is covered on its outer side (44) remote from the wall element (1) with a distribution body (47) provided with fluid channels (45, 46) to which the openings (42, 43) in the plate (41) open.

30. Device according to claim 17, characterised in that said wall element (1) is housed in the pressure vessel (25) in the form of a module (24).

31. The device according to claim 19 or 30, characterized in that the pressure vessel (25) has a lid (28) with a partition (29) and two connecting sleeves (34, 35) for the delivery of the two reactants (R1, R2), the partition (29) being mountable on the distribution member (37, 38).

32. The device according to claim 17, characterized in that the slot width(s) of the reaction space (3) can be varied by changing the thickness of the partition (13).