DE102020007214A1 - Process and reactor for exothermic reactions in the gas phase - Google Patents

Abstract

The invention relates to a method and reactor for exothermic reactions in the gas phase. The object of the invention is to provide a method and a reactor with which it is possible on an industrial scale to use cross-flow plate heat exchangers with slender flow channels for treating a gas loaded with undesirable constituents or for exothermic reaction between gases by changing the reaction behavior of the catalyst bed In the flow channels of the heat exchanger, the risk of blockage of the flow channels filled with catalyst and the formation of hot spots in the catalyst bed is reduced, the marginal access of the gas past the catalyst is largely avoided while at the same time increasing economy and safety Task by using at least one modified cross-flow plate heat exchanger (1) with flow channels (9) open to flow from the distribution space (3) to the collecting space (5) with a clear width (W) of at least 10 to max imal 80 mm of a flow channel (9), flow transitions (17) between adjacent flow channels (9), flow baffles (19) positioned in the flow channels (9) and flow paths (SF) for the cooling medium (K) located in the flow spaces (12) Flow guide and spacer plates (22) in the following steps: a) Simultaneous generation of turbulence in the partial flows of the mixture of process gas (G) and reaction gas (RG) within the flow channels (9) and in the cooling medium (K) within the flow spaces (12) , b) dividing the gas mixture of process gas and reaction gas into bypass flows (BS) during the catalytic reaction and introducing the bypass flows (BS) into the passage openings (18) of the flow transitions (17) directed sideways into the adjacent flow channels (9).

Description

The invention relates to a method for the exothermic reaction between gases, for example for the catalytic treatment of a gas loaded with undesirable gaseous components, in particular process gases, in which a reaction gas such as oxygen, hydrogen or carbon monoxide is added to the process gas or carbon dioxide is reacted with hydrogen on a catalyst , the gas mixture is heated to the reaction temperature in a heater and, via a supply-side distribution space of at least one plate heat exchanger, a large number of flow channels filled with a catalyst bed, which are formed by corrugated and / or profiled sheets that are mirror-inverted by webs and are combined to form pairs of corrugated or profiled sheets , flows through in parallel divided partial flows, the undesired constituents being oxidized or burned on the catalyst of the catalyst bed and the heat of reaction through a flow chamber, di e are formed between the corrugated or profiled sheet metal pairs, the cooling medium conducted to the flow channels is indirectly discharged in a cross flow, and the partial flows, after leaving the flow channels, are discharged as clean gas via a collecting space on the downstream side,

The invention further relates to a reactor for carrying out the process, with at least one plate heat exchanger, which comprises a plurality of flow channels arranged next to one another and filled with a catalyst bed and flow spaces lying perpendicular to them, which are made up of corrugated and / or corrugated sheet metal pairs, which lie on top of one another and are connected by webs. or profiled sheets are formed, the flow spaces being arranged between the pairs of corrugated sheets, and the flow channels for the passage of the partial flows separated by the process gas and reaction gas on the inflow side with a distribution space and on the outflow side with a collecting space, the inflow side distribution space with a supply line for a mixture of process gas and reaction gas and the collecting space on the downstream side is in connection with a clean gas line, and the flow spaces in a distribution space for supplying and removing a cooling medium to the indi direct cooling of the catalyst bed open to flow.

State of the art

The removal of undesired components from gases by means of catalysts has long been part of the state of the art. For example, catalysts made of platinum, palladium or their mixtures are used, which are placed in a bed through which the gas to be cleaned flows ( DE 33 18 098A1 , DE 35 05 351 A1 , DE 197 54 185 C1 , DE 198 09 200 A1 ), or in a bed arrangement of the catalyst between heat exchanger plates ( DE 103 61 515 A1 , EP 0 534 295 A1 , EP 2 718 086 B1 , EP 1 284 813 B1 , DE 603 17 545 A2 ) are available.

In the classic catalytic conversion, the gas to be cleaned flows through the reactor filled with catalyst granulate, the undesired constituents being oxidized in an exothermic reaction with the release of heat on the catalyst. A complete description of a catalyst bed includes the shape, size and size distribution of the catalyst particles. In the case of a catalyst bed in a fixed bed, there is a very large ratio of the bed dimensions to the particle size, so that the disruptive influence of the wall delimiting the bed is negligible. In a pipe with a small inner diameter, this interference is no longer negligible, because the bulk density is lowest directly on the wall and therefore results in a lower pressure loss, which leads to a higher flow velocity, the so-called edge accessibility. Experience has shown that the catalyst beds have a particle size distribution with a deviation from the mean particle size, as a result of which the particles with a smaller size fill the gaps between the larger particles, so that the bulk density in the vicinity of the wall also increases, so that the marginal accessibility is negligible . If the bulk density increases, the pressure loss also increases and the properties of the bed change with regard to the flow velocity, the mixing properties and the interaction with the catalyst or the reaction behavior as well as the heat transport ( DE 20 2006 014 118 U1 ).
In contrast to the precision tubes used in tube bundle reactors with almost constant internal diameters, which are intended to ensure largely the same properties of the catalyst bed, flow channels in cross-flow plate heat exchangers do not have a constant internal width due to production, so that the bulk density is not the same from flow channel to flow channel and the reaction behavior in the Flow channels is different.
The conversion reactions are predominantly exothermic in nature. ie the heat released during the oxidation can, due to the different reaction behavior, promote the formation of so-called hot spots in the catalyst bed, which leads to the catalyst being unusable.

In addition to the arrangement of the catalyst as a bed in the fixed bed or the arrangement of the catalyst between heat exchanger plates, the filling of an inner tube is also an option Plate heat exchanger with a catalyst or with packing known ( DE 34 11 675 A1 ). A device is proposed for heat and mass exchange between two or more flowable media or for initiating a reaction between the media with an inlet and an outlet for one medium and an inlet and outlet for the other medium and at least two enclosing pipes from where one is connected to the one and the other to the other inlet / outlet. Both ends of the inner tube are passed through the outer tube, which protrudes with its ends. The inner tube can be filled with a catalyst or with packing. A plurality of surrounding inner and outer tubes can also be arranged next to one another and the inner and outer tubes can also be formed with plates that are spaced apart and run parallel to one another.

Furthermore, from the DE 198 09 200 A1 an apparatus, in particular known for use as a chemical reactor and / or adsorber and / or regenerator, which is essentially cylinder-symmetrical about a preferred axis and contains at least two beds of particles that have a catalytic and / or adsorptive and / or heat-storing effect. The apparatus has means for supplying and removing gaseous or liquid media, which are each assigned to the ends of the beds facing away from one another and the ends facing one another.

In the EP 1 975 539 A2 discloses a heat exchanger or chemical reactor comprising a heat exchange body defining one or more fluid flow channels and having a removable insert. The insert includes a series of contact plates stacked along a common axis and press fit into one of the flow channels thereby providing secondary heat exchange surfaces in thermal contact with the primary wall surfaces.

According to this prior art, there are two basic systems for introducing a catalyst into a flow channel through which the process fluid flows. The first option is to arrange the catalyst as a supported layer in the flow channel ( EP 1 195 193 B1 , EP 1 361 919 B1 , EP 1 430 265 B1 , DE 11 2006 000 447 T5 , EP 1 434 652 B1 , WO 03/095924 A1 ). The particle size in these cases is less than 0.15 mm, so that this approach is suitable for flow channels with small cross-sections and closed flow channels of plate heat exchangers. In the second option, the catalyst or the adsorbent is introduced as a bed or packing into a relatively open, unobstructed flow passage with larger flow cross-sections ( WO 2006/075 163 A2 ). The particle sizes used here are more than 2 to 3 mm. If the catalyst packing is used up, it must be removed from the flow channels by pressing the packing through a rod inserted into the flow channel.

Both systems have serious disadvantages. Due to its complicated construction, the first system is to a certain extent a one-way system, because the catalyst or the adsorbent can only be removed after it has been used up with relatively high technical effort or the apparatus even has to be scrapped.

In the second system, a blockage of individual flow channels by the catalyst bed located in the flow channels cannot be safely ruled out, which leads to the economic efficiency of the process being adversely affected. In addition, the consumption of catalyst increases, which increases the operating costs of the process.

Another disadvantage that should not be neglected is that in particular the flow channels filled with catalyst and having small cross-sectional areas tend to allow the process gas to pass the edge of the catalyst. For small cross-sections of the flow channels, cross-flow plate heat exchangers have therefore not been able to establish themselves as reactors on an industrial scale.

Task

In this prior art, the invention is based on the object of providing a method and a reactor with which it is possible to use cross-flow plate heat exchangers with slim flow channels on an industrial scale for treating a gas contaminated with undesirable constituents or for exothermic reaction between gases, by equalizing the reaction behavior of the catalyst bed in the flow channels of the heat exchanger, reducing the risk of blocking of the flow channels filled with catalyst and the formation of hot spots in the catalyst bed, largely avoiding the passage of the gas past the catalyst while at the same time increasing economy and safety becomes.

This object is achieved by a method of the type mentioned at the outset with the features of claim 1 and by a reactor with the features of claim 13.

Advantageous embodiments of the method according to the invention and of the reactor can be found in the subclaims.

The solution according to the invention is based on the knowledge to use small cross-sectional flow channels of a catalyst-filled cross-flow plate heat exchanger for the mass transfer between the gas and the catalyst and, at the same time, for the heat exchange with the catalyst in the form of cooling during the oxidation, in cross-flow or counter-flow to use the flow channels guided by the mass transfer.

1. a) gleichzeitiges Erzeugen von Turbulenzen in den Teilströmen des Gemisches aus Prozessgas und Reaktionsgas innerhalb der Strömungskanäle und im Kühlmedium innerhalb der Strömungsräume,
2. b) Aufteilen des Gasgemisches aus Prozessgas und Reaktionsgas in Bypassströme während der katalytischen Reaktion und Einleiten der Bypassströme in die Durchtrittsöffnungen der Strömungsübergänge seitwärts gerichtet in die benachbarten Strömungskanäle.

This is achieved by using at least one modified cross-flow plate heat exchanger with flow channels open to flow from the distribution chamber to the collecting chamber with a clear width of at least 10 to a maximum of 80 mm, flow transitions between adjacent flow channels, flow baffles positioned in the flow channels and flow paths for the cooling medium forming flow paths - and spacer plates in the following steps:

1. a) simultaneous generation of turbulence in the partial flows of the mixture of process gas and reaction gas within the flow channels and in the cooling medium within the flow spaces,
2. b) Dividing the gas mixture of process gas and reaction gas into bypass flows during the catalytic reaction and introducing the bypass flows into the passage openings of the flow transitions, directed sideways into the adjacent flow channels.

According to a preferred embodiment of the method according to the invention, the turbulence in the gas mixture of process gas and reaction gas is generated by flow baffles, which are formed as expressions perpendicular and / or transverse to the flow direction in the wall of the flow channel at the same time as the corrugated bending or corrugated rolling of the corrugated sheets, the expressions are aligned inwardly into the flow channel and / or outwardly into the flow space.

The flow chicanes contribute to the fact that the partial flow of the process gas entering the flow channel is also directed into the interior of the flow channel and turbulence is generated, which counteracts the formation of marginal accessibility along the wall of the flow channel. The turbulence generated also has the advantage that the cooling medium is swirled directly on the surface by the features directed outwards into the flow spaces and thus improves the heat exchange.

According to a further advantageous embodiment of the method according to the invention, the turbulence in the cooling medium is generated by flow baffles or spacer plates positioned in the flow spaces between the pairs of corrugated sheets, the cooling medium being able to be guided in cross flow to the flow channels during the catalytic reaction.

In the event that the cooling medium is to be guided in several ways, adjacent flow spaces are alternately connected to one another, as a result of which the cooling medium is diverted from flow space to flow space.

The flow guide and spacer plates in the flow spaces between the pairs of corrugated sheets force a constant deflection of the cooling medium flowing past the flow channels, so that the indirect heat exchange with the catalytic converter is highly effective. At the same time, the flow guide and spacer plates ensure a precise distance between the corrugated sheet metal pairs lying above or below one another and enable a stable and compact design.

Another preferred embodiment of the method according to the invention provides that the size of the passage opening for the bypass flow is determined by the number of flow transitions, the respective passage opening being adapted to a size and shape that is smaller than the size and shape of the smallest particle size of the catalyst bed is. The passage opening of a flow transition thus defines a cross-sectional area over which a certain amount of the partial flow divided by the process gas and entering the respective flow channel reaches the adjacent flow channel as a bypass flow, so that the size of the bypass flows with the cross-sectional area of all passage openings and their distribution along the webs determined and a uniform or uneven distribution of the bypass flows over the adsorbent in the respective adjacent flow channel can be achieved.

For example, the number of flow transitions in the webs near the supply-side distribution space can be greater than the number of flow transitions in the webs near the discharge-side distribution space, i.e. the number of flow transitions distributed along the webs can vary.

This has the extraordinary advantage that any blocking of the Gas mixture dissolves or is interrupted at the passage openings of the flow transitions.

According to a preferred embodiment of the method according to the invention, the flow transition can be formed from a recess / groove formed in the webs of the corrugated or profiled sheets during the corrugation rolling of the corrugated or profiled sheets, which when the corrugated or profiled sheets are placed on top of one another is covered by the area of the webs above or below and the one on top of the other Bars are materially connected by laser welding or brazing, with a weld seam being penetrated by the depression in the longitudinal direction of the bars and the depression being sealed gas-tight by weld seams in the transverse direction of the bars.

According to a further variant of the method according to the invention, when the corrugated or profiled sheets are loosely superposed, the flow transition is formed from a flat gap between the webs, in that the webs are materially connected by laser line welding with weld seams in such a way that the gap interrupts the weld seam in the longitudinal direction of the webs and the gap is sealed gas-tight by weld seams running parallel on both sides in the transverse direction of the webs.

In a further embodiment of the method according to the invention, the clean gas can be fed to a cooler and condensed water can be separated from the clean gas. By adding an adsorption drying system downstream, the water content in the clean gas can be further reduced to a value of less than 1 ppmv.

The further embodiment of the method according to the invention provides that loose beds are used as the catalyst, which include the following materials: palladium, platinum, vanadium, tungsten, chromium, molybdenum, titanium, manganese, cobalt, nickel, silver, copper, zinc, iron, Aluminum, silicon, magnesium, phosphorus, beryllium and its oxides, barium, ruthenium or their mixtures with a mean particle size between 0.6 and 6.0 mm can be used.
The cooling medium used is water or a water-glycol mixture or thermal oil.

1. a) die Strömungskanäle haben eine lichte Weite von mindestens 10 bis maximal 80 mm,
2. b) benachbarte Strömungskanäle sind durch in die Stege eingeformte Strömungsübergänge zum seitwärts gerichteten Einleiten von Bypassströmen aus dem jeweiligen Teilstrom des Gasgemisches in die Strömungskanäle verbunden,
3. c) in den Strömungskanälen sind Strömungsschikanen zum Erzeugen von Turbulenzen im jeweiligen Teilstrom des Gasgemisches innerhalb der Strömungskanäle angeordnet und
4. d) in den Strömungsräumen zwischen den Wellblechpaaren sind Strömungspfade bildende Strömungsleit- und Abstandsbleche zum Erzeugen von Turbulenzen im Kühlmedium angeordnet.

The object is achieved with the reactor according to the invention in that the plate heat exchanger is a modified cross-flow plate heat exchanger with flow channels that are open from the distribution chamber to the collecting chamber and have the following features:

1. a) the flow channels have a clear width of at least 10 to a maximum of 80 mm,
2. b) Adjacent flow channels are connected by flow transitions formed in the webs for the sideways introduction of bypass flows from the respective partial flow of the gas mixture into the flow channels,
3. c) flow baffles for generating turbulence in the respective partial flow of the gas mixture are arranged in the flow channels within the flow channels and
4. d) in the flow spaces between the pairs of corrugated sheets, flow guide sheets and spacer sheets that form flow paths are arranged for generating turbulence in the cooling medium.

According to a preferred embodiment of the reactor according to the invention, the flow guide and spacer sheet comprises a thin corrugated sheet with spacer profiles which are formed into the wave crests and exceed the height of the wave crests and are arranged offset to one another from wave crest to wave crest, with the spacer profiles in the areas of the webs Above and below one another, corrugated sheet metal pairs intervene in a supporting manner and the respective spacer profile is fixed in a materially bonded manner at each end on the associated corrugated sheet metal pair.

This has the advantage that the flow guide and spacer plates not only generate the turbulence in the cooling medium, but at the same time also keep the corrugated iron pairs formed from the mirror-inverted corrugated iron sheets at a distance from one another, so that the cooling medium flows in cross-flow to the flow channels during the catalytic reaction. or can be guided through the flow spaces in several ways without hindrance.

Furthermore, the flow guide and spacer plates contribute to a compact design of the reactor according to the invention.

In order to largely prevent the partial flows of the gas mixture from passing along the edge of the catalyst, it is essential that the flow chicanes are formed by shapes that are transverse and / or parallel to the flow direction of the respective partial flow of the gas mixture into the wall of the flow channels inwards and / or from the wall are molded facing outwards.

The flow baffles make it possible to direct the partial flow of the process gas entering the respective flow channel into the interior of the channel and to generate turbulence that causes the To counteract marginal accessibility, especially in flow channels with a small cross-section.

In a further preferred embodiment of the reactor according to the invention, the flow transition is arranged transversely to the longitudinal direction of the webs, the passage openings of which open into the adjacent flow channels, the flow transition being formed from at least one indentation / groove formed in the web, which is from the area above or below of the laterally arranged web is covered, wherein the webs are cohesively connected in the longitudinal and transverse directions.
The material connection can comprise weld seams or brazed connections produced by laser line welding.

In a further expedient embodiment of the invention, the flow transition can consist of at least one flat gap with passage openings between the webs which are materially and gas-tightly connected in the longitudinal direction with a weld seam, the webs being sealed gas-tight in the transverse direction by welds running parallel to the gap.

The passage openings associated with the depression or the gap have a geometry or shape that is smaller than the dimensions and shape of the smallest particle size of the catalyst bed, so that catalyst particles cannot get from one flow channel into the other.

According to a particularly preferred embodiment of the reactor according to the invention, the passage opening of the flow transition has a cross-sectional area via which a certain amount of the partial flow of the gas mixture that has entered the flow channel reaches the respective adjacent flow channel as a bypass flow, the respective passage opening being adapted to a size and shape that is smaller than the size and shape of the smallest particle size of the catalyst bed. This ensures that the particles of the catalyst bed cannot get into adjacent flow channels via the passage opening.

According to a further preferred feature of the reactor according to the invention, the flow transitions are arranged vertically uniformly or at different lengths from one another and distributed in the longitudinal direction of the respective web. This arrangement has the advantage that the bypass flows separated by the passage openings can be distributed over the entire length of the flow channel into the catalyst bed.

In a particularly advantageous embodiment of the reactor according to the invention, the flow channels on the inflow and outflow side are covered with a sieve that can be flowed through and dismantled by process gas, reaction gas and clean gas, the mesh size of which is smaller than the smallest particle size of the catalyst bed. If it becomes necessary to replace the catalyst, the sieve can be dismantled from the flow channels and the used catalyst bed can be easily removed via the distribution chamber on the feed side. The flow channels are filled with new catalyst after removing the outflow-side screen and reassembling the inflow-side screen vertically into the open flow channels via the outflow-side distribution space.

According to a further development of the reactor according to the invention, a reaction gas line for admixing reaction gas in the flow direction upstream of the heater is incorporated into the supply line for the process gas.

Another embodiment of the reactor according to the invention provides that a cooler with a condensate drain for condensed water is integrated into the clean gas line. Of course, an economizer can also be used for heat recovery.

It is of particular importance for the reactor according to the invention that the cooling circuit assigned to the flow spaces for the heat exchange in the cross-flow ensures that the heat of reaction can be dissipated directly at the point where it is generated, thereby smoothing out the reaction behavior on the catalyst and at the same time avoiding overheating of the catalyst bed.

According to a further feature of the reactor according to the invention, the catalyst consists of a loose bed of particles, which comprises the following materials: palladium, platinum, vanadium, tungsten, chromium, molybdenum, titanium, manganese, cobalt, nickel, silver, copper, zinc, iron, Aluminum, silicon, magnesium, phosphorus, beryllium and its oxides, barium, ruthenium or their mixtures with a mean particle size between 0.6 and 6.0 mm.

According to a further feature of the invention, the particle size is matched to the dimensions, the cross section and the shape of the flow channels in such a way that the particles are at a small distance from the wall of the flow channel for high heat conduction.

A particularly preferred embodiment of the reactor according to the invention provides that the modified cross-flow plate heat exchanger forms a rectangular structural unit, which is arranged in the interior of a rectangular or cylindrical housing, the distribution space being designed as a foot part, the collecting space being designed as a head part and the distribution space for the cooling medium enclosing all flow spaces with open flow.

According to a further development of the invention, the structural unit has an inflow-side base and an outflow-side base, the respective base consisting either of a single molded part or of several molded parts adapted to the contour of the flow channels, which are firmly connected to each other and to the corrugated sheet metal bar.

In a further embodiment of the reactor according to the invention, several structural units are arranged vertically one above the other in a common housing, each structural unit being provided with an inflow-side distribution space, an outflow-side collection space and a distribution space for the cooling medium and the distribution spaces and collection spaces being flow-connected to one another through the flow channels.

The modified cross-flow plate heat exchangers consist of thin stainless steel sheet, carbon steel sheet, copper or aluminum sheet with a thickness of 0.1 mm to 1.0 mm, which is formed into corrugated or profiled sheet with different profile shapes by corrugated rolling. The corrugated sheets can have a semicircular, oval, triangular, trapezoidal or square profile, so that when the profiled or corrugated sheets are placed on top of one another, the resulting flow channels have a tubular, wave-like, rhombic, rectangular or polygonal cross-section.

Further advantages and details emerge from the following description with reference to the accompanying drawings.

Figure list

The invention is to be explained in more detail below using two exemplary embodiments.

• 1a eine perspektivische Explosionsdarstellung von zwei zueinander versetzte, spiegelbildlich übereinander angeordnete Wellblechpaare, in deren aufeinanderliegenden stoffschlüssig verbundenen Stegen mindestens ein Strömungsübergang aus Einsenkungen eingeformt ist,
• 1b einen Schnitt entlang der Linie A-A der 1a
• 1c einen Schnitt entlang der Linie B-B der 1b,
• 1d einen Schnitt entlang der Linie C-C der 1b
• 2 einen Ausschnitt in Draufsicht der 1a,
• 3 eine perspektivische Darstellung des in den Strömungsräumen zwischen den Wellblechpaaren eingesetzten Strömungsleit- und Abstandsbleches.
• 4a eine perspektivische Darstellung einer aus mehreren Wellblechpaaren zusammengesetzten Baueinheit mit kopf- und fußseitigem Boden,
• 4b den Aufbau des Bodens in einer Explosionsdarstellung,
• 5 ein Beispiel von Strömungsschikanen in der Wandung eines Strömungskanals in perspektivischer Darstellung,
• 6 eine Seitenansicht eines modifizierten Kreuzstrom-Plattenwärmeaustauschers mit zuführseitigem Verteilraum für das Gasgemisch aus Prozessgas und Reaktionsgas und abführseitigem Sammelraum für das Reingas in einem viereckigen Gehäuse,
• 7 eine Seitenansicht eines modifizierten Kreuzstrom-Plattenwärmeaustauschers im Innenraum eines zylindrischen Gehäuses,
• 8 eine Seitenansicht eines modifizierten Kreuzstrom-Plattenwärmeaustauschers aus beispielsweise zwei übereinander angeordneten Ba ueinheiten,
• 9 eine Explosionsdarstellung von zwei zueinander versetzte, im Steg in Längsrichtung stoffschlüssig verbundene Wellblechpaare mit Strömungsübergang, der durch einen Spalt gebildet ist,
• 9a einen Schnitt entlang der Linie D-D der 9,
• 9b einen Schnitt entlang der Linie E-E der 9a und
• 10 eine schematische Darstellung des erfindungsgemäßen Verfahrens.

Show it

• 1a a perspective exploded view of two mutually offset, mirror-inverted pairs of corrugated sheet metal, in whose mutually cohesively connected webs at least one flow transition is formed from depressions,
• 1b a section along the line AA of 1a
• 1c a section along the line BB of 1b ,
• 1d a section along the line CC of the 1b
• 2 a detail in plan view of the 1a ,
• 3 a perspective view of the flow guide and spacer plate used in the flow spaces between the pairs of corrugated sheets.
• 4a a perspective view of a structural unit composed of several pairs of corrugated iron with a bottom at the top and bottom,
• 4b the structure of the floor in an exploded view,
• 5 an example of flow chicanes in the wall of a flow channel in a perspective view,
• 6th a side view of a modified cross-flow plate heat exchanger with a feed-side distribution space for the gas mixture of process gas and reaction gas and a discharge-side collection space for the clean gas in a square housing,
• 7th a side view of a modified cross-flow plate heat exchanger in the interior of a cylindrical housing,
• 8th a side view of a modified cross-flow plate heat exchanger from, for example, two building units arranged one above the other,
• 9 an exploded view of two mutually offset corrugated sheet metal pairs that are cohesively connected in the web in the longitudinal direction with a flow transition formed by a gap,
• 9a a section along the line DD of 9 ,
• 9b a section along the line EE of the 9a and
• 10 a schematic representation of the method according to the invention.

The 1a shows the basic structure of pairs of corrugated iron 7c made from mirror-inverted corrugated sheets 7a and 7b consist of stainless steel with a thickness of 0.3 mm. The corrugated iron 7a and 7b form with their corrugated profiles 8th vertical flow channels lying parallel next to one another 9 , their webs 10a or. 10b facing each other.
In the jetty 10a or. 10b is transverse to the longitudinal direction LR over the entire width B of the web 10a or. 10b at least one depression 14a or. 14b formed in the corrugated rolling of the corrugated or profiled sheets 7a or. 7b is introduced.
The depressions 14a or. 14b come when the corrugated or profiled sheets are mirrored on top of each other 7a or. 7b to lie upside down and be removed from the jetty 10a or. 10b of the corrugated or profiled sheet metal above and below 7a or. 7b covered. The flat areas of the webs facing one another 10a or. 10b lie on top of each other and support each other. The webs are used for gas-tight connections 10a or. 10b mechanically pressed together, fixed and by laser welding or brazing in the longitudinal direction LR gas-tight connected.
The depressions 14a or. 14b thus penetrate in the longitudinal direction LR running material connection / weld seam 16a in the transverse direction QR . The gas-tight connection between webs on top of each other 10a or. 10b takes place through parallel to the respective depression 14a or. 14b running further weld seams 16b like from the 1b and 1c can be found.
Because the depressions 14a or. 14b Depressions in the webs 10a or. 10b represent, the webs touch in the area of the depressions 14a or 14 do not and remain unwelded, so that a flow transition 17th with openings 18th arises, which in the respective adjacent flow channels 9 flow out.

The depressions 14a or. 14b have a depth T that are smaller than the smallest grain size of the catalyst of the catalyst bed KS so that no catalyst particle can get from one flow channel into the other flow channel.

Through the flow transition 17th a sideways bypass flow arrives during the catalytic reaction BS from the partial flow TG of the gas mixture from process gas G and reaction gas RG into the adjacent flow channels 9 . This makes it possible to counteract an incipient blockage in the flow channels.
One recognizes from the 1b that the cross-sectional area QF the passage opening 18th on the geometry and shape of the depression 14a or. 14b depends. The dimension of the passage opening 18th is chosen so that the smallest grains of the catalyst particles cannot pass through the passage opening.

The mirror-inverted corrugated or profiled sheets 7a and 7b form a layer of a pair of corrugated iron 7c out. The corrugated iron pairs 7c are arranged above or below one another and are offset from one another 24 on, with the corrugated iron pairs lying above or below one another 7c are spaced apart and flow spaces between them 12th form in which a cooling medium K in cross flow to the flow channel 9 catchy, ie through all flow spaces at the same time 12th can be performed. But it is also possible to use the cooling medium K multi-thread, ie one after the other through the flow spaces 12th respectively. In such a case, there are adjacent flow spaces 12th connected to each other, creating the cooling medium K is diverted from flow space to flow space.
The corrugated or profiled sheets 7a or. 7b have a semicircular, oval, triangular, trapezoidal or square profile 8th so that when the corrugated or profiled sheets are placed on top of each other 7a or. 7b the resulting flow channels 9 can have a tubular, wave-like, rhombic, rectangular or polygonal cross-section.

In the flow spaces 12th between the pairs of corrugated iron 7c is -as also 2 shows a flow guide and spacer plate shaped like a corrugated sheet 22nd used. In the wave crests WB of the flow guide and spacer plate 22nd are spacer profiles at regular intervals from one another 23 molded, each reciprocally in the by the offset 24 formed area of the corrugated iron pairs arranged one above the other 7c engage in a supporting manner, the spacer profile 12th on the respective pair of corrugated iron 7c at the beginning and end is firmly attached, so that a displacement of the flow guide and spacer plate 22nd in the flow space 12th is excluded. The flow guide and spacer plates 22nd contribute to the stiffening of the corrugated iron pairs arranged above or below one another 7c at.

To 3 are the spacer profiles 23 in the adjacent wave crests WB of the flow guide and spacer plate 2 to each other on gap 25th staggered so that flow paths SF arise that the cooling medium conducted in cross-flow K force to deflect and generate turbulence in the process. An example of a flow path SF is indicated by arrows in the 3 marked.

The 4a and 4b illustrate the structure of one of several pairs of corrugated iron 7c composite structural unit 1a . The corrugated iron pairs 7c penetrate with their open-ended flow channels 9 a head-side floor 26th and a downstream floor 27 .
The floors 26th and 27 are composed of molded parts 26 to 26.n or 27.1 to 27.n, the contour of which is based on the shape and dimensions of the corrugated sheet metal pairs 7c , expediently by laser cutting. The molded parts are made with the inserted pairs of corrugated iron 7c Assembled along the contour and materially connected by laser welding or brazing, so that an essentially rectangular structural unit is created, which can optionally be in a rectangular or cylindrical housing 2 can be used. The joining direction is indicated by an arrow in the 4b marked.

It is known that slender columns with a ratio of bulk and particle diameter <20 tend to pass the edges ( K.Salem, dissertation “Unsteady temperature and concentration fields in highly loaded fixed bed adsorbers”, Cuvillier-Verlag Göttingen, 2006 ). BAKER ET AL ("The Course of Liquor Flow in Packed Towers", Trans AIChE 31 (1935), pp. 296-315 ) indicate that the tendency towards edge penetration increases significantly with a ratio of column diameter to packing diameter of 8: 1.
In order to counteract the marginal accessibility, the flow channels have 9 -as in 5 shown- flow chicanes 19th that are in the corrugated profile 8th the corrugated iron 7a or. 7b with corrugated rolling in the form of characteristics 21 be molded and from the wall 20th into the interior of the flow channels 9 protrude into and / or from the wall 20th into the flow space 12th for the cooling medium K stepping out. The manifestations 21 are transverse and parallel to the direction of flow SRR of the partial flow TG of the gas mixture on the wall 20th the flow channels 9 arranged distributed. The flow chicanes 19th cause the gas located near the wall to enter the interior of the flow channel 9 is steered and thus turbulence are generated, which largely prevent the edge accessibility.

The 6th shows the structure of the reactor according to the invention in a side view in section. The modified cross-flow plate heat exchanger 1 is as a unit 1a in one housing 2 made of stainless steel. The case 2 consists of a rectangular casing 2a , in the interior of which the structural unit 1 is arranged. The bottom at the head 26th is together with one to the housing 2 belonging headboard 28 at the front on the wall 29 of the housing jacket 2a flanged so that a distribution space on the inflow side 3 for the gas mixture of process gas G and reaction gas GR arises, in which the gas mixture over one with the head part 28 connected supply line 4th entry.
The bottom at the foot 27 the unit 1a and one on the wall 29 of the housing jacket 2a Foot part flanged on the front 30th form a collecting space 5 for which the flow channels 9 leaving clean gas RG , the one with the footboard 30th connected discharge line 6th is fed to a consumer, not shown, or released into the atmosphere as exhaust air.
The upstream distribution space 3 is located at the top of the cross-flow plate heat exchanger 1 , making the current direction SRR of the gas mixture from process gas G and reaction gas GR vertically downward through the assembly 1a runs. Of course, the gas mixture can be the structural unit 1a also flow vertically upwards.

The flow channels filled with a catalyst 9 are preferably aligned vertically and connect the distribution space with an open flow 3 with the collecting room 5 .
The flow channels are upstream and downstream 9 each end with a removable, gas-permeable sieve 11 covered. The sieve 11 has a mesh size that is selected to be smaller than the smallest grain size in the flow channels 9 Filled particles of the catalyst bed KS so that the catalyst cannot get out of the flow channels.
The flow channels 9 have a clear width ( W. ) of at least 10 to a maximum of 80 mm. For example, the length of the flow channels 1 to 2 m and the mean particle size of the catalyst are 0.6 to 6 mm.

The process gas contaminated with an undesirable gaseous component G occurs together with a reaction gas GR via the feed line 4th in the distribution room 3 and divides into partial flows TG on, each of which has a flow channel filled with a catalyst, for example palladium or platinum 9 flows through and is catalytically converted on the catalyst. The modified cross-flow plate heat exchanger has on the downstream side 1 a collection room 5 for the clean gas RG that has a drainage pipe 6th is fed to a consumer not shown further.
The inside of the case 2 arranged structural unit 1a is for the supply and discharge of a cooling medium K from a distribution room 13th surrounded, the one between the wall 29 of the housing jacket 2a and the assembly 1a is trained. The flow spaces 12th between the pairs of corrugated iron 7c open to flow into the distribution area 13th a.

To 7th is the modified cross-flow plate heat exchanger 1 in the interior of a cylindrical housing 2 arranged. The bottom at the head 26th the unit 1a rests on the wall 29 of the housing jacket 2a of the housing 2 on and is together with the headboard 28 in the form of a dished bottom and the bottom at the foot 27 the unit 1a with the foot part 30th forehead or. at the foot of the wall 29 of the cylindrical housing jacket 2a flanged. The distribution room 3 and the collecting room 5 are through the headboard 28 and the foot part 30th with the corresponding floors 26th or. 27 the unit 1a educated.
The modified cross-flow plate heat exchanger 1 consists of thin stainless steel, copper or aluminum corrugated sheet with a thickness between 0.1 and 3.0 mm,

In 8th a reactor is shown which consists of two structural units arranged one above the other 1a consists, the two structural units in a common housing 2 are housed.

The 9 , 9a and 9b shows a second embodiment of a flow transition 17th between adjacent flow channels 9 .

The flow transition 17th is through a shallow gap 15th when laying the corrugated or profiled sheets loosely on top of each other between the webs 10a and 10b educated. The bridges 10a or. 10b are interconnected by a lengthways LR running weld seam 16a gas-tight connected by at least one gap 15th is interrupted. The gap 15th represents a flow transition 17th with openings 18th represents the adjacent flow channels 9 Connect with each other so that there is no flow. The gap 15th is in the transverse direction QR the footbridges 10a or. 10b through welds 16b sealed gas-tight (see 9b) .

By the number, geometry and shape of the flow transitions 17th can be the size or amount of in the flow channels 9 arriving bypass flows BS will affect. For example, depending on the design, the number of flow transitions 17th between adjacent flow channels 9 be increased or decreased so that the cross-sectional area QF depending on the type of process gases and the catalyst KS can be adjusted and a blockage of the flow channels 9 due to an even or uneven distribution of the bypass flows BS can be counteracted via the catalyst column.

The method according to the invention is described below with a modified cross-flow plate heat exchanger 1 for the catalytic gas cleaning of a process gas loaded with undesired gaseous components, for example process gas loaded with hydrogen, oxygen, carbon monoxide or hydrocarbons.

The 9 shows the schematic representation of the method according to the invention.

In the upstream distribution room 3 of cross-flow plate heat exchange 1 leads the supply line 4th for the process gas G that through a to the feed line 4th connected fan 31 in the distribution room 3 is promoted. In the feed line 4th is an electrically operated heater 32 involved. A reaction gas line 33 for admixing the reaction gas GR , for example hydrogen, oxygen or carbon monoxide, into the process gas G , leads upstream of the heater in the direction of flow 32 into the feed line 4th . Mixing in the reaction gas GR into the process gas G takes place in a stoichiometric ratio tailored to the catalyst and the component to be removed with a certain excess of, for example, 0.1%.

At the discharge line 6th directly at the exit of the collecting room 5 there is a first measuring probe 34 and downstream of this first measuring probe 34 a second measuring probe 35 showing the concentrations of the reaction gas GR in the clean gas RG measure up. The measuring probes 34 and 35 belong to an automatic controlled system 36 which one of the measuring probe 34 assigned butterfly valve 37 with switching valve 38 , which is the reaction gas line 33 opens or closes, and one of the measuring probe 35 assigned control valve 39 comprises that the amount of reaction gas GR keeps constant at a minimum value, so that only the absolutely necessary amount of reaction gas, even in the case of strongly fluctuating operating conditions GR is consumed.
The measuring probes 34 and 35 , the switching valve 38 and control valve 39 are via control lines 31 with a control unit 41 connected, which is the amount of the admixed reaction gas GR supervised.

In the heater 32 is the gas mixture of reaction gas GR and process gas G heated to a temperature at which the following reactions take place on the catalyst, depending on the presence of the gas components in the process gas: 2H ₂ + O ₂ = 2H ₂ O 2 CO + O ₂ = 2 CO ₂ KWST + ... O ₂ = ... CO ₂ + ... H ₂ O. On the one in the flow channels 9 If the palladium or platinum catalyst is present, the oxygen and hydrogen are converted to water or carbon monoxide to carbon dioxide. These reactions are very exothermic. The heat of reaction is generated by a cooling medium where it is generated K , here water, continuously dissipated in indirect heat exchange.

Immediately above the distribution area 3 of the cross-flow plate heat exchanger 1 one opens through a shut-off valve 42 openable and closable feed line 43 for the cooling medium K into the flow spaces 12th one that is in cross flow to the flow channels 9 vertically ascending into the flow space 12th below the collecting area 5 into one through a shut-off valve 44 openable and closable drainage line 45 for the cooling medium to be discharged K leads. The direction of flow of the cooling medium K runs horizontally ascending in the direction of flow of the divided partial flows TG of the gas mixture from process gas G and reaction gas GR . The direction of flow is indicated by arrows.
The distribution room 13th assigned flow spaces 12th are simultaneously with a shut-off valve 46 openable and closable Drain line 47 for draining the cooling medium K connected.
The heater 32 who have favourited shut-off valves 42 , 44 and 46 are via the control lines 40 with the control unit 41 electrically connected, which are the control commands for the shut-off valves 42 and 44 depending on the heater 32 set reaction temperature outputs.

The the flow channels 9 leaving cleaned substreams TG from process gas G and reaction gas GR are in the collecting room 5 merged and via the discharge line 6th as clean gas RG discharged.

For any condensed water in the clean gas RG is the discharge line 6th with a cooler 48 connected to the water via a condensate drain 49 ejected.

The shut-off valve is during the oxidation 50 in the feed line 4th for the process gas G open. The shut-off valves belonging to the cooling circuit are also included 42 and 44 open, but the shut-off valve 46 the drain line 47 closed.

The process gas heated to the reaction temperature G with admixed reaction gas GR thus reaches the distribution room 3 , divides into partial flows TG on that directed vertically upwards in those with catalyst KS filled flow channels 9 pour in.

The undesired gas components, here hydrogen, oxygen, carbon monoxide or hydrocarbons, oxidize with the reaction gas on the catalyst GR to water and carbon dioxide.

The heat of reaction generated during the oxidation is transferred to the flow channels in a cross flow 9 in the flow spaces 12th guided cooling medium K , here water, constantly discharged. This has the extraordinary advantage that the reaction conditions in the individual flow channels are made more uniform.

The process according to the invention will be explained in more detail below using two examples.

Example A.

A process gas contaminated with oxygen G is to be cleaned with the method according to the invention.

• Katalysator: 0,3% Platin oder Palladium auf Aluminiumoxid-Gel
• Katalysatorgröße: 1,0 bis 2,5 mm
• Länge der Strömungskanäle: 1.000 mm
• Weite der Strömungskanäle: 20 mm
• Eintrittskonzentration: 2,0 Vol.% O₂
• Austrittskonzentration: < 10 ppmv O₂
• Durchsatz: 660 m³/h
• Druck: 1,1 bara
• Wassergehalt am Eintritt: ca. 1 g/Nm³
• Temperaturerhöhung ohne Kühlung: ca. 340°C
• Abzuführende Reaktionswärme: ca. 80 kW
• Kühlmedium: Wasser Eintritt 35°C
• Reaktionsgas: H₂
• Reaktionsgasverbrauch: ca. 28 m³/h
• Reaktionsprodukt: H₂O ca. 21,1 kg/h

The following operating data are based on:

• Catalyst: 0.3% platinum or palladium on alumina gel
• Catalyst size: 1.0 to 2.5 mm
• Length of the flow channels: 1,000 mm
• Width of the flow channels: 20 mm
• Inlet concentration: 2.0% by volume O ₂
• Exit concentration: <10 ppmv O ₂
• Throughput: 660 m ³ / h
• Pressure: 1.1 bara
• Water content at the inlet: approx. 1 g / Nm ³
• Temperature increase without cooling: approx. 340 ° C
• Heat of reaction to be dissipated: approx. 80 kW
• Cooling medium: water inlet 35 ° C
• Reaction gas: H ₂
• Reaction gas consumption: approx. 28 m ³ / h
• Reaction product: H ₂ O approx. 21.1 kg / h

A residual content of less than 10 ppmv oxygen was achieved in the cleaned process gas.

In the present example, the method according to the invention proceeds as follows. The mixture of process gas G and reaction gas GR is in the distribution room 3 of the cross-flow plate heat exchanger 1 via the feed line 4th and the fan or compressor 31 fed.

The reactor consists of a package of 10 pairs of stainless steel corrugated iron 7c each with a dimension of 1,000 x 2,000 mm, the one facing vertically upwards with a catalyst KS filled flow channels 9 each with a diameter of 20 mm, which are interconnected by flow transitions 17th stay in contact. The vertical flow channels 9 are by one in flow spaces 12th guided cooling medium K flows around in a cross flow, whereby the in the flow channel 9 on the catalyst KS The mass transfer that takes place in the heat exchange with the cooling medium K so that the resulting reaction heat of approx. 80kW is dissipated where it is generated.
As a catalyst KS platinum or palladium on an aluminum oxide gel with a particle size of 1.0 to 2.5 mm is used, which is inserted into the flow channels 9 is poured.

Example B.

• Katalysator: Nickel, Zirkoniumdioxid stabilisiert
• Katalysatorgröße: 1,0 bis 3,0 mm
• Länge der Strömungskanäle: 1.000 mm
• Weite der Strömungskanäle: 20 mm
• Eintrittskonzentration: 80 Vol.% H₂, 20 Vol.% CO₂
• Eintrittstemperatur: ca. 120 bis 150°C (Kompressionswärme vom Verdichter)
• Durchsatz: 699 m³/h
• Druck: 13,0 bis 18,0 bar
• Reaktionstemperatur am Katalysator: 20 bis 350°C
• Abzuführende Reaktionswärme: ca. 260 kW
• Kühlmedium: Thermalöl bei 2,0 bis 4,0 bar

With the method according to the invention, a hydrogen produced regeneratively with an electrolyser is intended to react catalytically with carbon dioxide to form methane (sebating process). This reaction is strongly exothermic and requires intensive cooling of the reactor. Sebating reaction: 4H ₂ + CO ₂ → CH ₄ + 2 H ₂ O The following operating data are based on:

• Catalyst: nickel, zirconium dioxide stabilized
• Catalyst size: 1.0 to 3.0 mm
• Length of the flow channels: 1,000 mm
• Width of the flow channels: 20 mm
• Inlet concentration: 80% by volume H ₂ , 20% by volume CO ₂
• Inlet temperature: approx. 120 to 150 ° C (compression heat from the compressor)
• Throughput: 699 m ³ / h
• Pressure: 13.0 to 18.0 bar
• Reaction temperature on the catalyst: 20 to 350 ° C
• Heat of reaction to be dissipated: approx. 260 kW
• Cooling medium: thermal oil at 2.0 to 4.0 bar

The reactor described in Example A is used. That in the cross flow in the flow spaces 12th as a cooling medium K guided thermal oil ensures an exactly adjustable reaction temperature over the entire area of the flow channels 9 , which leads to low by-product formation and thus to a very good methane yield. The resulting reaction heat of approx. 260 kW can be dissipated very well both radially and axially and decoupled with the thermal oil and used well for further energetic use. Local overheating of the catalytic converter is avoided by the uniform dissipation of heat.
In the compact, easily scalable reactor according to the invention, inexpensive bulk catalysts can be used which, in contrast to coated tubular, honeycomb or multiphase catalysts, can be easily exchanged.

The one between the flow channels 9 existing flow transitions 17th allow at least one bypass flow BS into the adjacent flow channels 9 . This enables an incipient blockage of the flow channels to be resolved and, at the same time, the reaction conditions in the individual flow channels despite the tolerance differences in the internal dimensions of the flow channels 9 and thus not to equalize the same bulk quantities of catalyst. The
in the flow channels 9 arranged flow chicanes 19th also act through the generation of turbulence of the edge accessibility in the flow channels 9 opposite.

List of reference symbols

1

Plattenwärmeaustauscher

1a

Baueinheit

2

Gehäuse

2a

Gehäusemantel von 2

3

zuflussseitiger Verteilraum von 1

4

Zuführleitung für Prozessgas G

5

abströmseitiger Sammelraum von 1

6

Abführleitung für Reingas RG

7a, 7b

Wellblech

7c

Wellblechpaar

8

Wellprofil von 7a, 7b

9

Vertikale Strömungskanäle in 1

10a, 10b

Stege von 7a, 7b

11

Sieb

12

Strömungsräume zwischen Wellblechpaaren 7c

13

Peripherer Verteilraum für Kühlmedium

14a, 14b

Einsenkung/Rille

15

Spalt

16a

Schweißnaht in LR

16b

Schweißnaht in QR

16c

Hartlötverbindung in QR und LR

17

Strömungsübergänge

18

Durchtrittsöffnungen von 17

19

Strömungsschikanen

20

Wandung von 9

21

Ausprägungen

22

Strömungsleit- und Abstandsblech

23

Abstandshalterprofil

24

Versatz der Wellblechpaare 7c

25

Lücken zwischen WB von 22

26

Kopfseitiger Boden von 1a

26.1-26.n

Formteile von 26

27

Fußseitiger Boden von 1a

27.1-27.n

Formteile von 27

28

Kopfteil von 1

29

Wandung von 2a

30

Fußteil von 1

31

Gebläse bzw. Verdichter

32

Erhitzer

33

Reaktionsgasleitung

34

Erste Messsonde

35

Zweite Messsonde

36

Regelstrecke

37

Absperrklappe

38

Schaltventil

39

Regelventil

40

Steuerleitungen

41

Steuereinheit

42

Absperrarmatur in 43

43

Zuführleitung für Kühlmedium

44

Absperrarmatur in 45

45

Abführleitung für Kühlmedium

46

Absperrarmatur in 47

47

Entleerungsleitung

48

Kühler

49

Kondensatablass

50

Absperrarmatur in 4

BS

Bypassstrom

G

Prozessgas

GR

Reaktionsgas

K

Kühlung/Kühlmedium

KS

Katalysator/Katalysatorschüttung

LR

Längsrichtung von 10a, 10b

QR

Querrichtung von 10a, 10b

QF

Querschnittsfläche von 18

RG

Reingas

SF

Strömungspfade für Kühlmedium

SRR

Strömungsrichtung der Teilströme TG von G und GR

T

Tiefe von 14a, 14b

TG

Teilströme von G und GR

W

Lichte Weite von 9

Modified cross flow

1

Plate heat exchangers

1a

Unit

2

casing

2a

Housing jacket of 2

3

Inflow-side distribution space from 1

4th

Feed line for process gas G

5

Downstream collecting space from 1

6th

Discharge line for clean gas RG

7a, 7b

Corrugated iron

7c

Corrugated iron pair

8th

Corrugated profile of 7a, 7b

9

Vertical flow channels in 1

10a, 10b

Ridges of 7a, 7b

11

Sieve

12th

Flow spaces between pairs of corrugated iron 7c

13th

Peripheral distribution space for cooling medium

14a, 14b

Recess / groove

15th

gap

16a

Weld in LR

16b

Weld in QR

16c

Brazed joint in QR and LR

17th

Flow transitions

18th

Passages from 17

19th

Flow chicanes

20th

Wall of 9

21

Expressions

22nd

Flow guide and spacer plate

23

Spacer profile

24

Offset of the corrugated iron pairs 7c

25th

Gaps between WB from 22

26th

Head-side bottom of 1a

26.1-26.n

Molded parts from 26

27

Bottom floor of 1a

27.1-27.n

Molded parts from 27

28

Headboard of 1

29

Wall of 2a

30th

Foot part of 1

31

Blower or compressor

32

Heater

33

Reaction gas line

34

First measuring probe

35

Second measuring probe

36

Controlled system

37

Butterfly valve

38

Switching valve

39

Control valve

40

Control lines

41

Control unit

42

Shut-off valve in 43

43

Supply line for cooling medium

44

Shut-off valve in 45

45

Discharge line for cooling medium

46

Shut-off valve in 47

47

Drain line

48

cooler

49

Condensate drain

50

Shut-off valve in 4

BS

Bypass flow

G

Process gas

GR

Reaction gas

K

Cooling / cooling medium

KS

Catalyst / catalyst bed

LR

Longitudinal direction of 10a, 10b

QR

Cross direction of 10a, 10b

QF

Cross-sectional area of 18

RG

Clean gas

SF

Flow paths for cooling medium

SRR

Direction of flow of the partial flows TG from G and GR

T

Depth of 14a, 14b

TG

Partial flows of G and GR

W.

Clear width of 9

QUOTES INCLUDED IN THE DESCRIPTION

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

Patent literature cited

• DE 3318098 A1 [0003]
• DE 3505351 A1 [0003]
• DE 19754185 C1 [0003]
• DE 19809200 A1 [0003, 0006]
• DE 10361515 A1 [0003]
• EP 0534295 A1 [0003]
• EP 2718086 B1 [0003]
• EP 1284813 B1 [0003]
• DE 60317545 A2 [0003]
• DE 202006014118 U1 [0004]
• DE 3411675 A1 [0005]
• EP 1975539 A2 [0007]
• EP 1195193 B1 [0008]
• EP 1361919 B1 [0008]
• EP 1430265 B1 [0008]
• DE 112006000447 T5 [0008]
• EP 1434652 B1 [0008]
• WO 03/095924 A1 [0008]
• WO 2006/075163 A2 [0008]

Non-patent literature cited

• K.Salem, dissertation "Unsteady temperature and concentration fields in highly loaded fixed bed adsorbers", Cuvillier-Verlag Göttingen, 2006 [0060]
• BAKER ET AL ("The Course of Liquor Flow in Packed Towers", Trans AIChE 31 (1935), pp. 296-315 [0060]

Claims (29)

Process for the exothermic reaction between gases, for example for the catalytic treatment of a gas contaminated with undesired gaseous components, in particular process gases, in which a reaction gas (GR) such as oxygen, hydrogen or carbon monoxide is added to the process gas (G) or carbon dioxide is mixed with hydrogen on a catalyst for reaction is brought, the gas mixture is heated in a heater (23) to reaction temperature and via a supply-side distribution space (3) of at least one plate heat exchanger (1) a large number of flow channels (9) filled with a catalyst bed (KS), which are mirror-inverted through Strips (10a, 10b) connected, corrugated and / or profiled sheets (7a, 7b) combined to form pairs of corrugated or profiled sheets (7c) are formed, flows through in parallel divided partial flows (TG), the undesired constituents on the catalyst of the catalyst bed (KS ) are oxidized or burned and the reaction s heat is indirectly removed by a cooling medium (K) conducted in cross-flow to the flow channels (9) in distribution spaces (13) formed between the corrugated or profiled sheet metal pairs (7c), and the partial flows (TG) after they leave the flow channels (9) are discharged as clean gas (RG) via a collecting space (5) on the downstream side, characterized by the use of at least one modified cross-flow plate heat exchanger (1) with flow channels (9) open to flow from the distribution space (3) to the collecting space (5) with a clear Width (W) of at least 10 to a maximum of 80 mm, flow transitions (17) between adjacent flow channels (9), flow baffles (19) positioned in the flow channels (9) and flow paths (SF) for the cooling medium (12) in the flow spaces (12) K) forming flow guide and spacer plates (22) in the following steps: a) simultaneous generation of turbulence in the partial flows of the mixture of process gas (G) and rea ction gas (RG) within the flow channels (9) and in the cooling medium (K) within the flow spaces (12), b) dividing the gas mixture of process gas and reaction gas into bypass flows (BS) during the catalytic reaction and introducing the bypass flows (BS) into the Passage openings (18) of the flow transitions (17) directed sideways into the adjacent flow channels (9). Procedure according to Claim 1 , characterized in that the turbulence in the gas mixture of process gas (G) and reaction gas (RG) is generated by flow baffles (19), which are designed as expressions (21) perpendicular and / or transverse to the flow direction (SRR) in the wall (20) of the Flow channel (9) are formed at the same time as the corrugated bending or corrugated rolling of the corrugated sheet metal, the embossments (21) being aligned inwards into the flow channel (9) and / or outwards into the flow space (12). Procedure according to Claim 1 , characterized in that the turbulence in the cooling medium (K) is generated by flow guide or spacer plates (22) positioned in the flow spaces (13) between the pairs of corrugated sheets (7c), the cooling medium (K) flowing into the cross-flow during the catalytic reaction Flow channels (9) is guided one or more threads. Procedure according to Claim 1 , characterized in that the size of the passage opening (18) for the bypass flows (BS) is determined by the number of flow transitions (17) in the respective flow channel (9), the respective passage opening (18) being adapted to a size and shape, which is smaller than the size and shape of the smallest particle size of the catalyst bed. Procedure according to Claim 1 , characterized in that several flow transitions (17) are evenly or differently spaced and distributed over the length of the flow channels (9). Procedure according to Claim 1 , characterized in that the passage opening (18) of a flow transition (17) defines a cross-sectional area (QF) over which a certain amount of the partial flow (TG) of the gas (G) entering the respective flow channel (9) as a bypass flow into the adjacent flow channel (19) so that the size is determined by the cross-sectional area of all passage openings (18) and their distribution results in a uniform or uneven distribution of the bypass flows (BS) over the catalyst bed (KS) in the respective adjacent flow channel (9). Procedure according to Claim 1 , characterized in that the flow transition (17) is formed from a recess / groove (14a, 14b) formed in the webs (10a, 10b) when the corrugated or profiled sheets (7a, 7b) are corrugated rolling - or profiled sheets (7a, 7b) is covered by the area of the webs (10a, 10b) above or below and the webs (7a, 7b) lying on top of one another are materially connected by laser welding or brazing, with a weld seam (16a) in the longitudinal direction of the webs ( 10a, 10b) is penetrated by the depression (14a, 14b) and the depression (14a, 14b) is sealed gas-tight by weld seams in the transverse direction of the webs (10a, 10b). Procedure according to Claim 1 , characterized in that the flow transition (17) is formed when the corrugated or profiled sheets (7a, 7b) are loosely superposed from a flat gap (15) between the webs (10a, 10b) by the webs (10a, 10b) together are connected by laser line welding with weld seams (16a, 16b) so that the gap (15) interrupts the weld seam (16a) in the longitudinal direction (LR) of the webs (10a, 10b) and the gap (15) is interrupted by weld seams running parallel on both sides ( 16b) is sealed gas-tight in the transverse direction (QR) of the webs (10a, 10b). Procedure according to Claim 1 , characterized in that the clean gas (RG) is fed to a cooler (39) and condensed water is separated from the clean gas (RG). Procedure according to Claim 1 , characterized in that the clean gas (RG) is then dried by adsorption. Procedure according to Claim 1 , characterized in that catalyst beds are used, the palladium, platinum, vanadium, tungsten, chromium, molybdenum, titanium, manganese, cobalt, nickel, silver, copper, zinc, iron, aluminum, silicon, magnesium, phosphorus, beryllium and its oxides , Barium, ruthenium or mixtures thereof with an average particle size between 0.6 and 6.0 mm. Procedure according to Claim 1 , characterized in that water or a water-glycol mixture or a thermal oil is used as the cooling medium (K). Reactor for carrying out the process according to Claim 1 , with at least one plate heat exchanger, which comprises a plurality of juxtaposed flow channels (9) filled with a catalyst bed (KS) and flow spaces (12) which are perpendicular to them and which are connected to one another by webs (10a, 10b) to form pairs of corrugated sheets ( 7c) combined corrugated and / or profiled sheets (7a, 7b) are formed, the flow spaces (12) being arranged between the pairs of corrugated sheets (7c), and the flow channels (9) for the passage of the process gas (G) and reaction gas ( GR) divided partial flows (TG) on the inflow side and outflow side of the plate heat exchanger are connected to a distribution space (3) with open flow, the inflow side distribution space (3) with a supply line (4) for a mixture of process gas (G) and reaction gas (GR) and the The collecting space (5) on the downstream side is in communication with a clean gas line (6), and the flow spaces (12) in a distribution space (13) for the inlet and outlet Discharge of a cooling medium (K) for indirect cooling of the catalyst bed (KS) open-flow, characterized in that the plate heat exchanger is a modified cross-flow plate heat exchanger (1) with flow channels (9) open to flow from the distribution space (3) to the collecting space (5) with the following features is: a) the flow channels (9) have a clear width (W) of at least 10 to 80 mm, b) adjacent flow channels (9) are through flow transitions (17) formed in the webs (10a, 10b) for the sideways introduction of Bypass flows (BS) of the gas mixture connected into the flow channels (9), c) in the flow channels (9) flow baffles (19) for generating turbulence in the gas mixture are arranged within the flow channels (9) and d) in the flow spaces (12) between the corrugated sheet metal pairs (7c) are arranged flow path (SF) forming flow guide and spacer sheets (22) for generating turbulence in the cooling medium (K). Reactor after Claim 13 , characterized in that the flow guide and spacer plate (22) comprises a thin corrugated metal sheet with spacer profiles (23) formed in the wave crests (WB) and exceeding the height of the wave crests (WB), which are spaced from wave crest to wave crest on gap (25). are arranged offset, the spacer profiles (23) engaging in a supporting manner in the offset (24) formed by the webs (10a, 10b) of the corrugated sheet metal pairs (7c) lying one above the other and the respective spacer profile (23) at each end on the associated corrugated sheet pair (7c) ) is firmly fixed. Reactor after Claim 13 , characterized in that the flow baffles (19) are formed from expressions (21) which transversely and / or parallel to the flow direction (SRR) of the partial flow (TG) of process gas (G) and reaction gas (RG) in the wall (20) of the flow channels (9) are formed inwardly and / or outwardly from the wall (20). Reactor after Claim 13 , characterized in that the flow transition (17) is arranged transversely to the longitudinal direction (LR) of the webs (10a, 10b), the passage openings (18) each opening into the adjacent flow channels (9), the flow transition (17) consisting of at least one in the web (10a, 10b) formed recess / groove) (14a, 14b) is formed, which is covered by the area above or below of the web (10a, 10b) arranged laterally reversed, the webs (10a, 10b) in longitudinal - and transverse direction (LR, QR) are firmly connected. Reactor after Claim 16 , characterized in that the cohesive connection between the webs (10a, 10b) are weld seams (16a, 16b) or brazed connections (16c). Reactor after Claim 13 , characterized in that the flow transition (17) consists of at least one flat gap (15) with passage openings (18) between the webs (10a, 10b) connected in a gas-tight manner in the longitudinal direction (LR) with a welded seam (16a), the The webs (10a, 10b) are connected in a gas-tight manner in the transverse direction (QR) by weld seams (16b) running parallel to the gap (15). Reactor after Claim 16 or 18th , characterized in that the passage openings (18) assigned to the depression / groove (14a, 14b) or the gap (15) have a geometry or shape which is smaller than the dimension and shape of the smallest particle size of the catalyst bed. Reactor after Claim 12 , characterized in that several flow transitions (17) are spaced apart from one another uniformly or of different lengths and distributed in the longitudinal direction of the web (10a, 10b), the passage opening (18) having a geometry and shape that is smaller than the smallest grain size of the adsorbent (AM) is. Reactor after Claim 16 or 18th , characterized in that the passage openings (18) of the flow transition (17) have a cross-sectional area (QF) via which a certain amount of the divided partial flow (TS) reaches the respective adjacent flow channel (9) as a bypass flow (BS). Reactor after Claim 13 , characterized in that the flow channels (9) on the inflow and outflow side are covered with a screen (11) through which the process gas (G), reaction gas (GR) and clean gas (G, RG) can flow, the mesh size of which is smaller than the smallest particle size of the Catalyst bed is. Reactor after Claim 12 , characterized in that the corrugated or profiled sheets (7a, 7b) have a semicircular, oval, triangular, trapezoidal or square profile (8), so that when the profiled or corrugated sheets (7a, 7b) are placed on top of one another, the flow channels (9 ) have a tubular, wave-like, rhombic, rectangular or polygonal cross-section. Reactor after Claim 13 , characterized in that the modified cross-flow plate heat exchanger (1) forms a rectangular structural unit (1a) which is arranged in the interior of a rectangular or cylindrical housing (2), the distribution space (3) as a head part (28), the collecting space (5) is designed as a foot part (30) and the distribution space (13) for the cooling medium (K) encloses all flow spaces (12) open to flow. Reactor after Claim 24 , characterized in that the structural unit (1a) has an inflow-side base (26) and an outflow-side base (27), the bases (26,27) each made of a single molded part or of several adapted to the contour of the corrugated sheet metal pairs (7c) Molded parts (26.1-26.n; 27.1-27.n) exist which are firmly connected to one another and to the corrugated sheet metal pairs (7c). Reactor after Claim 13 , characterized in that the catalyst (KS) has a particle size which is matched to the dimensions, the cross section and the shape of the flow channels (9) so that the catalyst particles are a small distance from the wall (20) of the flow channel (9) for have a high thermal conductivity. Reactor after Claim 13 , characterized in that the catalyst (KS) comprises a loose bed of particles, the palladium, platinum, vanadium, tungsten, chromium, molybdenum, titanium, manganese, cobalt, nickel, silver, copper, zinc, iron, aluminum, silicon, Magnesium, phosphorus, beryllium and its oxides, barium, ruthenium or their mixtures with an average particle size between 0.6 and 6.0 mm. Reactor after Claim 13 , characterized in that several structural units (1a) are arranged vertically one above the other in a common housing (2) and that each structural unit (1a) has an inflow-side distribution space (3), an outflow-side collection space (5) and a distribution space (13) for the Cooling medium (K) is provided, the distribution spaces (3) and the collecting spaces (5)) being flow-connected to one another through the flow channels (9). Reactor after Claim 13 , characterized in that the modified cross-flow plate heat exchanger (1) consists of thin stainless steel, carbon steel, copper or aluminum sheet.

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