Measuring device for measuring the axial temperature profile in a reactor tube

Abstract

It is proposed in the context of the present invention: - a measuring device for measuring the axial temperature distribution in a reactor tube, - a connection for connecting the reactor tube to a feed pipe which is configured as a thermal stress compensator for a reaction input stream and for laterally introducing a multi-point thermocouple into the reactor tube, - the use of the connection / measuring device for measuring the axial temperature distribution in a reformer tube for the steam reforming of hydrocarbons, and - a method for installing the measuring device.

Description

Technical Field

[0001] This invention relates to:

[0002] - A measuring device used to measure the axial temperature distribution in reactor tubes.

[0003] - A connector for connecting the reactor tubes to a feed line configured for the reactor input flow and for a thermal stress compensator that laterally introduces multi-point thermocouples into the reactor tubes.

[0004] - Connection / measuring equipment used for measuring the axial temperature distribution in reformer tubes for steam reforming of hydrocarbons, and

[0005] - A method for installing measuring equipment.

[0006] The present invention particularly relates to a measuring device for measuring the axial temperature distribution of syngas in one or more reformer tubes in a reforming apparatus for steam reforming hydrocarbons to provide a syngas product comprising hydrogen and carbon oxides. Background Technology

[0007] Measuring devices for measuring the axial temperature distribution in reactor tubes, particularly those containing solid particulate catalyst as a tilting bed, are known and described in the literature. Such measuring devices are crucial for the evaluation and control of reactor behavior, especially when the reactor is intended to perform strongly endothermic or exothermic heterogeneous catalytic reactions at high reaction temperatures.

[0008] Understanding the precise axial temperature distribution in reactor tubes, such as those in reformers used for steam reforming hydrocarbons to provide syngas, leads to a better understanding of the processes underway and results in optimized and safer control of the reformer equipment. This information is invaluable for preventing excessively high temperatures, particularly under unsteady-state conditions, thereby preventing thermal damage to the reformer tubes and limiting the risk of unwanted carbon formation within them. The axial temperature distribution measured in the reformer tubes allows for a very precise determination of the actual extent to which reaction equilibrium has been achieved. Furthermore, temperatures measured under actual conditions provide a good basis for future reactor configurations.

[0009] However, introducing thermocouples into the reformer tubes is challenging due to the high pressure and high temperature conditions. The thermocouple sensors must also be thin enough to prevent disruption of the catalyst bed's porosity, and a pressure seal must be ensured.

[0010] Several multipoint thermocouple systems have recently been commercially introduced, reportedly allowing for the measurement of internal temperature distribution within reactor tubes. These systems are configured to withstand varying, and in some cases extreme, temperature and pressure operating conditions. Such multipoint thermocouples are typically mounted such that the sensor's compression fitting is located at the upper end of the tube, for example, in the upper flange, typically used only for catalyst packing. In this arrangement, the input gas mixture is introduced into the reactor tube via a lateral short tube into the reactor. Thus, in the case of a reformer tube, a superheated carbon dioxide-vapor mixture is introduced into the reformer tube through the lateral short tube, while the multipoint thermocouple is introduced axially through the entry-side sealing flange, aligned with the longitudinal axis of the reformer tube.

[0011] The corresponding arrangement of measuring equipment and reactor tubes is in Figure 1 This is illustrated by way of example and also disclosed in U.S. Patent Application US 2016 / 0263542 A1. The multipoint thermocouples described therein are constructed as an integral system and consist of approximately ten individual thermocouples / thermocouple sensors arranged in an Inconel shell and embedded in an electrical insulator. These thermocouple sensors are arranged at different heights. The integral system is mounted along the axis of the reactor tube along with the catalyst loading section, and a damper system is used to attenuate the fall of catalyst particles during loading via the upper flange of the reactor tube, thereby preventing them from breaking. Centering of the multipoint thermocouple assembly in the reactor tube is achieved by spacers / centerers, which are successively removed upwards during the loading of the reactor tube with catalyst. The multipoint thermocouples pass axially through the inlet-side sealing flange, aligned with the longitudinal axis of the reformer tube, and are electrically connected to an accompanying signal acquisition device via a transmitter. The measured temperature can then be displayed and / or transmitted to downstream data processing equipment, such as a process control system.

[0012] The described arrangement of multi-point thermocouples has certain drawbacks when used in reformer tubes for steam reforming of hydrocarbons. The high reactor temperatures that occur during steam reforming cause the reformer tubes to become significantly longer relative to ambient conditions during operation. To reduce the resulting thermal stress, the inlet side and, typically, the outlet side of the reformer tubes are connected to the inlet / outlet gas distributor system via thermal stress compensators in the form of elbows or coils, described in the art as “pigtails.” These are connected between the reformer tubes and the feed line to the superheated hydrocarbon-steam mixture, and are joined thereto by welded or flanged connections. The lateral arrangement of the feed line means that thermal stresses still act on the already highly thermally stressed reformer tubes, acting perpendicular to the longitudinal axis of the reformer tubes and thus potentially causing deformation. Furthermore, from a flow engineering perspective, it is disadvantageous for the input gas to flow from the input pipe at an angle of up to 90° to the reformer tube, as this can lead to the formation of relatively high-temperature zones where the cracking of introduced hydrocarbons increases, resulting in localized coke deposition. For example, a low-flow zone (dead zone) forms above the connection point of the feed pipe in the reformer tube, which is subject to localized overheating and therefore carries a particular risk of undesirable localized coke formation and deposition. Therefore, in the steam reforming of hydrocarbons, it would be advantageous to supply the hydrocarbon-steam mixture via a feed pipe arranged aligned with the longitudinal axis of the reformer tube, and would at least mitigate the aforementioned disadvantages. Figure 1 The multipoint thermocouples shown or described in US 2016 / 0263542A1 may no longer be used in the manner described. Therefore, there is a need for a device that can easily introduce multipoint thermocouples into the reformer tubes even when the reformer tubes and feed lines are axially aligned. Summary of the Invention

[0013] Therefore, the object of the present invention is to enable the use of multi-point thermocouples inside the reformer tube for catalytic steam reforming of hydrocarbons in a configuration in which input gas is vertically introduced into the reformer tube through the upper or lower end of the reformer tube using a feed pipe. In this configuration, the feed pipe, configured as a thermal stress compensator or a feed pipe equipped with a thermal stress compensator, and the reformer tube are arranged such that their longitudinal axes are aligned and they are hermetically connected, for example, by means of a flange on the inlet side end of the reformer tube.

[0014] In one aspect, this objective is achieved by the connector of the present invention, in another aspect by the measuring device of the present invention, and in yet another aspect by the method of the present invention for mounting the measuring device. Further embodiments of the invention are apparent in this disclosure. The invention further relates to the use of the aforementioned connector and / or measuring device for measuring the axial temperature distribution in a reformer tube for steam reforming of hydrocarbons.

[0015] Thermal stress compensators should be understood as flexible elements used to compensate for pipe movement, particularly due to thermal variations in the length of, for example, reactor tubes. This compensation is achieved mechanically, for example through flexible bellows or through elbows, loops, or coils, which can elastically deform in the direction of compensation while continuing to perform their primary function as conduits that are fluidly sealed relative to the environment. For example, the high reactor temperatures that occur during steam reforming cause the reformer tubes to become significantly longer relative to environmental conditions during operation. To reduce the resulting thermal stress, the inlet side (feed pipe) and typically the outlet side of the reformer tubes are connected to the inlet / outlet gas distributor system via thermal stress compensators in the form of elbows or coils, described in the art as “pigtails.” They are connected between the reformer tubes and the inlet pipe of the superheated hydrocarbon-steam mixture and / or between the reformer tubes and the outlet pipe for the produced crude synthesis gas, and are connected thereto by welded or flanged connections.

[0016] Transition or reduction parts should be understood as fittings or conical pipe fittings that can be arranged inside a pipe to form a transition between two different nominal pipe widths.

[0017] References to the inlet and outlet of a pipe or reactor refer to the direction of flow of fluid (e.g., gas) through the pipe or reactor during its intended use.

[0018] Multipoint thermocouples, acting as multipoint temperature distribution sensors, measure the temperature at various points along their length. Their configuration includes ungrounded (insulated) connections to multiple measurement points arranged along the sensor's length. Commercially available multipoint thermocouples allow for the measurement of temperatures up to 1000°C over lengths of tens of meters. These temperature sensors are commonly used in the chemical and petrochemical industries because their use facilitates the acquisition of temperature profiles from chemical reactors.

[0019] For the purposes of this invention, the fluid connection between the two regions of the device of this invention is any type of connection that allows fluid (e.g., a gas flow) to flow from one region to the other, regardless of any region or component located between them. Specifically, a direct fluid connection should be understood to mean any type of connection that allows fluid (e.g., a gas flow) to flow directly from one region to the other without the insertion of another region or component, with exceptions for purely transport operations and the means required for this purpose, such as pipes, valves, pumps, compressors, and reservoirs. An example is a pipe that provides direct access from one region to the other.

[0020] For the purposes of this invention, an apparatus is something that enables or facilitates the achievement of an objective. Specifically, a fixing device should be understood as a physical article that a person skilled in the art would consider for forming a preferably hermetically tight connection between two equipment components. Fixing devices that allow multi-point thermocouples to feed through and be hermetically secured in a feed line are particularly configured in the form of compression fittings, extrusion fittings, or cut-ring fittings, and are commercially available. Some of the listed fixing devices are detachable and reusable connections, while others are suitable for reuse.

[0021] Data processing equipment should be understood to refer to a computer or any other measuring or control device suitable for generating manipulated variables for specific process parameters of a reactor apparatus from measured individual temperatures / measured temperature distributions according to a defined algorithm. This could be, for example, the flow rate of the reactor feed or the burner output in a reformer furnace.

[0022] This invention is based on the finding that aligning tube elements equipped with thermal stress compensators with the reactor tubes themselves is advantageous for reducing mechanical stress caused by the elongation of the reactor tubes due to thermal expansion. This elongation is particularly pronounced in reformer tubes used for steam reforming hydrocarbons, as the tubes are heated from ambient temperature to reaction temperatures approaching 1000°C during online operation. Lateral arrangements of feed pipes, as known in the art, generate thermal stresses acting perpendicular to the longitudinal axis of the reformer tubes, which can thus cause deformation. Furthermore, deflecting the input gas flow direction 90° from the input pipe into the reformer tubes is disadvantageous, as this can lead to the formation of relatively high-temperature regions where increased cracking of introduced hydrocarbons occurs, resulting in localized coke deposition.

[0023] Therefore, in the steam reforming of hydrocarbons, supplying the hydrocarbon-steam mixture via a feed pipe arranged aligned with the longitudinal axis of the reformer tubes would be advantageous and would at least reduce the aforementioned disadvantages, but Figure 1The multipoint thermocouples shown or described in US 2016 / 0263542 A1 may no longer be used in the manner described.

[0024] The present invention solves these problems when a connection is provided between the inlet end (inlet end) of the reactor tube and the feed pipe, which is intended to introduce the reactor input flow into the reactor tube and is configured as a thermal stress compensator; if the inlet end of the reactor tube and the feed pipe have different nominal widths / inner diameters or different flange dimensions, or if an insulating material of pipe shape has been introduced into the inlet end of the reactor tube, this also serves as a reduction or transition piece.

[0025] According to the invention, the first end of the connector has the same inner diameter as the inlet end of the reactor tube or the tubular insulation introduced into the inlet end of the reactor tube. This is particularly beneficial in the case of reformer tubes, as it reduces localized coking by avoiding dead zones or flow separation edges at the inlet end of the reactor tube.

[0026] Insulation elements of the type described can be introduced into the inlet of the reactor tube, particularly the reformer tube, to achieve greater insulation for this tube. Since the gas mixture entering the reactor tube via the feed pipe exhibits its highest temperature during steam reforming, insulation in this area helps minimize heat transfer to the pipe and supporting steel structure. The insulation elements used for this purpose are in the shape of pipe sections or hollow cylinders and are made, for example, of a material with a lower thermal conductivity than the reactor tube. The insulation elements are introduced into the inlet of the reactor tube before the installation of the connectors and secured there using methods known to those skilled in the art. Furthermore, when using such insulation elements, the connectors according to the invention also facilitate the installation and removal of the feed pipe configured as a thermal stress compensator (pigtail pipe), because the installation / removal of the feed pipe is now carried out in the longitudinal axis direction of the reactor tube, instead of perpendicular to the longitudinal axis as in the case of a feed pipe with a thermal stress compensator according to the prior art.

[0027] The inlet end of the reactor tube, the connector, and the outlet end of the feed pipe, such as the cylindrical outlet end of a feed pipe with a circular cross-section, are arranged back-to-back with their longitudinal axes aligned during installation and are airtightly connected, for example by welding or preferably by flange connection, since flange connection is non-destructive, detachable, and therefore reusable. According to the invention, the connector is attached with an airtight guide tube leading to the connector and having a fixing device at its end opposite to the connector. The fixing device may include, for example, an external thread attached to the end of the guide tube and a corresponding compression fitting, extrusion fitting, or cutting ring fitting, which allows for feedthrough and airtight fixation of multi-point thermocouples. Importantly, the angle between the common longitudinal axis of the reactor tube, connector, and feed pipe outlet end on one hand, and the longitudinal axis of the guide tube on the other hand, is between 15° and 60°, preferably between 20° and 45°, and this angle points in the direction of the feed pipe, i.e., away from the reactor tube. This allows for the use of guide tubes to introduce multi-point thermocouples into the reactor tube without requiring excessive force and simultaneously avoiding excessive deformation of the multi-point thermocouples. Compared to individual thermocouples, the bending radius of multi-point thermocouples is more limited because a corresponding thermocouple must be provided for each temperature measurement point, and typically all thermocouples and their power leads are embedded in a common shell tube. While multi-point thermocouples are flexible, their flexibility is limited due to the greater thickness of the arrangement compared to individual thermocouples.

[0028] Preferred embodiments of the present invention

[0029] A second aspect of the connector according to the invention is characterized in that the first section, the second section, the at least one transition member, and the guide tube, or a combination of these elements, are single-piece or multi-piece but can be hermetically connected, such that all elements in the connected state are fluidly connected to each other. Thus, for example, the first section, the second section, and a transition member, or a combination of two or more transition members (e.g., cylindrical straight pipe sections arranged between the transition members) can be configured as a common assembly and produced by metal casting, by 3D printing, by welding two or more turned parts together, or alternatively by machining from solid materials. The guide tube is then advantageously hermetically connected to the common assembly by welding.

[0030] A third aspect of the connector according to the invention is characterized in that, in this connected state, the common longitudinal axis of the connector coincides with the center point of the inlet end of the reactor tube and the center point of the outlet end of the feed pipe. In this way, the occurrence of thermal stress is effectively reduced, especially the thermal stress occurring perpendicular to the longitudinal axis of the reactor tube. Furthermore, since dead zones are avoided, localized coke deposition due to the undesirable thermal cracking of introduced hydrocarbons is reduced.

[0031] A fourth aspect of the connector according to the invention is characterized in that the first section and / or the second section includes a flange capable of being hermetically connected to a flange mating member at the inlet end of the reactor tube and / or the outlet end of the feed pipe. The flange connection provides the possibility of a hermetically tight connection and is non-destructively removable, thus allowing for reuse.

[0032] A fifth aspect of the connector according to the invention is characterized in that the end of the guide tube facing away from the connector includes external thread and pipe thread connectors, extrusion fittings, compression fittings, or cutting ring fittings as fixing devices. Such fixing devices, which allow for feedthrough and airtight fixing of multi-point thermocouples in the feed line, are commercially available. Some of the listed fixing devices provide detachable and reusable connections and are therefore suitable for reuse. This is important because typically evacuating the reactor tube requires removing the multi-point thermocouples, and subsequently reinstalling them when filling the reactor tube with fresh catalyst.

[0033] A sixth aspect of the present invention relates to a measuring device for measuring the axial temperature distribution in a reactor tube, the measuring device comprising:

[0034] (a) The aforementioned connector,

[0035] (b) Multi-point thermocouples,

[0036] (c) At least one centering body for centering the multi-point thermocouple in the reactor tube, wherein the centering body comprises:

[0037] (c1) Inner ring, which allows the feedthrough of the multi-point thermocouple.

[0038] (c2) A plurality of spacers arranged radially relative to the inner ring and equidistantly along the outer side of the inner ring, wherein the spacers have the same length, and the length is selected such that when the centering body is introduced into the reactor tube, the center point of the inner ring coincides with the longitudinal axis of the reactor tube, and the plane formed by the spacers is arranged perpendicular to the longitudinal axis of the reactor tube. Centering bodies of this type are known in themselves and are described, for example, in U.S. Patent Application US 2016 / 0263542 A1. However, the use of a centering body in connection with this invention is particularly important because the low maximum bending radius of multipoint thermocouples makes their safe guidance and centering particularly important.

[0039] In a seventh aspect of the invention, a measuring device for measuring the axial temperature distribution is disposed in a reactor tube containing a tilted bed of solid particulate catalyst, characterized in that the average distance between two adjacent spacers is greater than the average length of the catalyst particles. This ensures that the catalyst particles fall past the centering body during the filling of the reactor tube and are not thus prevented from doing so, as this would hinder the formation of a compact tilted bed of catalyst.

[0040] An eighth aspect of the invention relates to a method for installing a measuring device according to the invention in a reactor tube for performing an endothermic or exothermic heterogeneous catalytic chemical reaction, the method comprising the steps of:

[0041] (a) Provide the reactor tube, the measuring device, the feed pipe for the reactor input flow, and the solid particulate catalyst as a loose solid.

[0042] (b) Pass the multi-point thermocouple through the feed pipe and through the inner rings of at least two, preferably at least three, centering bodies.

[0043] (c) Using these centering bodies, the multi-point thermocouple is introduced into the interior of the reactor tube through the inlet end of the reactor tube.

[0044] (d) The solid particulate catalyst is packed to the specified filling height.

[0045] (e) Connect the connector airtightly to the inlet end of the reactor tube.

[0046] (f) Connect the connector airtightly to the discharge end of the feed pipe.

[0047] (g) The multi-point thermocouple is hermetically fixed in the guide tube using the fixing device.

[0048] This method can be used advantageously, especially when the centrifugal body does not interfere with the reaction process and can be retained in the reactor tubes during reactor operation.

[0049] When performing the method for installing the measuring device according to the invention in the reactor tube, it must be ensured that the multi-point thermocouples ideally do not contact the inner wall of the reformer tube, as this may lead to measurement errors in subsequent temperature measurements.

[0050] In a ninth aspect of the invention, the method for installing a measuring device is characterized in that...

[0051] (h) Perform the packing of the solid particulate catalyst up to the lower edge of the lowest centering body.

[0052] (i) Raise the lowest centering body by a specified length along the longitudinal axis of the reactor tube.

[0053] (j) Repeat steps (h) and (i) until the specified fill height is reached.

[0054] (k) Remove at least one centering body before connecting the connector to the reactor tube.

[0055] This method represents an alternative to the aforementioned aspects of the invention, wherein the centering element interferes with the reaction / reactor operation and therefore must be removed before the reactor tubes are connected. For this purpose, it is necessary to remove the centering element(s) before the connectors are attached to the reactor tubes, according to step (d). This is possible, for example, when the centering element is cut along its side, allowing removal from the side of the multi-point thermocouple, although this results in the destruction of the centering element. Therefore, it is advantageous when the centering element is multi-piece and two or more parts are connected, for example, by threaded connections, as this allows the centering element to be reused in the next filling operation.

[0056] In a tenth aspect of the invention, the method for installing a measuring device is characterized by using a flange connection and / or a welded connection to perform an airtight connection between the connector and the inlet end of the reactor tube and / or an airtight connection between the connector and the outlet end of the feed pipe. If performed correctly, both connection types can provide an airtight connection and withstand high pressure. Furthermore, the flange connection offers the advantages of reversibility, disassembly, and reusability.

[0057] The eleventh aspect of the invention relates to the use of connectors and / or measuring devices for measuring the axial temperature distribution in reformer tubes of a hydrocarbon vapor reforming process. The connectors and measuring devices according to the invention are particularly suitable for this application because the elongation of the reformer tubes is particularly large during the heating of the reformer equipment from ambient temperature to the reaction temperature. The length of the reformer tubes is typically 10 meters or longer, and the elongation caused by thermal expansion may be several decimeters.

[0058] Work Example

[0059] The development, advantages, and possible applications of this invention are also apparent from the following description of the work, numerical examples, and accompanying drawings. All features described and / or depicted constitute the invention on their own or in any combination thereof, regardless of how they are combined in the claims or in reverse reference therein. Attached Figure Description

[0060] In these diagrams:

[0061] Figure 1 An example of a reactor tube for catalytic steam reforming of hydrocarbons, having a measuring device for measuring axial temperature distribution, is shown, according to prior art (e.g., US 2016 / 0263542 A1).

[0062] Figure 2 An example of a connector according to the invention is shown, which is used to connect a reactor tube for catalytic steam reforming of hydrocarbons to a feed line configured for the reactor inlet flow and for laterally introducing a multi-point thermocouple into a thermal stress compensator within the reactor tube.

[0063] Figure 3 An example of a reactor tube for catalytic steam reforming of hydrocarbons is shown, the reactor tube having a measuring device for measuring the axial temperature distribution, the measuring device having an installed connector according to the invention.

[0064] Figure 4 An example of a reactor tube for catalytic steam reforming of hydrocarbons is shown in an alternative embodiment when a tubular insulation has been introduced into the inlet end of the reactor tube. The reactor tube has a measuring device for measuring the axial temperature distribution, which has an installed connector according to the invention. Detailed Implementation

[0065] Figure 1 This is an exemplary schematic diagram of a reactor tube 1 for catalytic steam reforming of hydrocarbons, according to prior art (e.g., US 2016 / 0263542 A1), having a measuring device for measuring the axial temperature distribution in the reactor tube. The arrangement shown includes a reactor tube 10 with an inlet side flange 12, which is sealed using a flange connection cap 14. The reactor tube is filled with a tilted bed 16 of particulate catalyst for steam reforming of hydrocarbons. The hydrocarbon to be reacted (e.g., methane, butane, or naphtha) is mixed with steam to provide a gaseous input mixture and, after heating in a heating device (not shown), introduced into the reactor tube 10 via a feed pipe 18. The flow conditions in the gaseous input mixture are indicated by flow arrows. It is evident that, after entering the reactor tube, a portion of the gaseous input mixture initially moves in the opposite direction to the main flow due to the formation of eddies. This is because a low-flow dead zone is formed in the internal volume region of the reactor tube between the inlet side flange and the feed pipe, where the longer residence time of the hot hydrocarbon-steam mixture results in undesirable coking.

[0066] The axial temperature distribution within the catalyst tilting bed is measured using a multi-point thermocouple 20, which is introduced into the reactor tube through an opening in the cap. Using a compression fitting 22, the multi-point thermocouple can be hermetically secured to the cap 14 relative to the environment, thereby preventing undesirable escape of input or product gases from the reactor tube under increased pressure. For this purpose, the opening in the cap 14 can, for example, be provided with an internal thread (not shown) that can be connected to a corresponding external thread on the compression fitting.

[0067] Multiple centering bodies 24 are used to fix multi-point thermocouples to the center of the reactor tube. These centering bodies are permeable to the gaseous input mixture and permeable to the individual catalyst particles during the filling of the reactor tube with catalyst.

[0068] The described arrangement of multi-point thermocouples has disadvantages when operating reactor tube 10 for steam reforming of hydrocarbons. During operation, the high reactor temperatures that occur during steam reforming cause the reformer tube to become significantly longer relative to ambient conditions. To reduce the associated thermal stress, the feed line is connected, for example, to a thermal stress compensator (not shown); alternatively, the feed line can also be configured as a thermal stress compensator. The lateral arrangement of the inlet line means that thermal stresses still act on the already highly thermally stressed reactor tube, acting perpendicular to the longitudinal axis of the reactor tube and thus causing deformation. Furthermore, deflecting the gas flow direction from the inlet line to the reactor tube at an angle of up to 90° is unfavorable, as this can lead to the formation of relatively high-temperature zones where increased cracking of the introduced hydrocarbons occurs, and thus localized coke deposition. For example, a low-flow zone (dead zone) forms in the reactor tube above the inlet line connection point, which is at particular risk of localized overheating and therefore undesirable localized coke formation.

[0069] therefore, Figure 2 A connector 30 according to the invention is shown, which overcomes the aforementioned problems and allows the reactor tube 10 to be connected to a feed pipe 34 configured for the reactor input flow and for a thermal stress compensator that laterally introduces multi-point thermocouples into the reactor tube. Connector 30 includes the following components:

[0070] (a) A first section 32 having, for example, a cylindrical first end pointing toward the inlet of the reactor tube 10 and having the same inner diameter as the inlet of the reactor tube and being hermetically connected thereto. In the example shown, the hermetically connected connection is achieved using a flange 33, which can be connected to the reactor tube 10 via a flange mating member 12. This is due to... Figure 2 The dashed line in the middle represents...

[0071] (b) A second section 34 having, for example, a cylindrical second end pointing toward the discharge end (shown in dashed lines) of the reactor tube 35 and having the same inner diameter as the discharge end of the feed pipe 35 and being hermetically connected thereto. Figure 2 As indicated, a connection can be created using the flange provided. An alternative connection possibility is to create a welded connection.

[0072] (c) Transition member 36, the first end of which has the inlet end of reactor tube 10 / inner diameter of the first section 32, and the opposite second end of which has the outlet end of feed pipe 35 / inner diameter of the second section 34.

[0073] (d) Components (a), (b) and (c) preferably have circular cross sections and longitudinal axes passing through the respective center points, wherein these components are arranged one after the other, their longitudinal axes are aligned, and thus coincide on a common longitudinal axis 40.

[0074] (e) The first section 32 has a guide tube 38 attached thereto, which is hermetically connected to and leads to the first section 32. The hermetically tight connection between the guide tube and the first section is preferably achieved by welding, and in alternative examples by flange connection. The guide tube 38 has a fixing device 22 at its end facing away from the first section, such as a pipe threaded connection, extrusion fitting, compression fitting, or cut ring fitting, wherein the fixing device allows for multi-point thermocouples ( Figure 2 Feedthrough and airtight fixing (not shown in the image).

[0075] (f) The angle α between the common longitudinal axis 40 and the longitudinal axis 42 of the guide tube is between 15° and 60°, preferably between 20° and 45°, wherein this angle points in the direction of the feed pipe. In other words, this angle is away from the reactor tube. Figure 2 In the example shown, the angle α is 45°. Studies have shown that this angle allows for the introduction of multi-point thermocouples through the inlet of the reactor tube using a guide tube without requiring excessive force or applying excessive deformation to the multi-point thermocouples. Compared to individual thermocouples, the bending radius of multi-point thermocouples is more limited because a corresponding thermocouple must be provided for each temperature measurement point, and in one example, all thermocouples are embedded together with their power leads in a common shell tube. While multi-point thermocouples are flexible, their flexibility is limited due to the greater thickness of the arrangement compared to individual thermocouples.

[0076] Figure 3 This is a schematic diagram of an example of a reactor tube 1 for catalytic steam reforming of hydrocarbons, having a measuring device 20 for measuring axial temperature distribution, wherein a connection 30 according to the invention is used to connect the reactor tube 10 to a feed pipe for an input gas containing hydrocarbons and steam. Figure 3 The measuring device 20 (not shown) is installed between [the two points]. This illustrates that the measuring device 20 (multi-point thermocouple) is introduced laterally via a guide tube and centered using a centering body 24. It should be noted that... Figure 3The configuration shown according to the invention allows for the introduction of input gas without dead zones. This reduces the degree of undesirable coke deposition in the inlet region of the reactor tubes.

[0077] Figure 4 This is a schematic diagram of an example of reactor tube 10, which is similar to Figure 3 The example configuration shown differs from the one in that the inlet end of the reactor tube is provided with a tubular insulation. Accordingly, the first section of the connector is configured with a narrowing at its first end pointing towards the inlet end of the reactor tube, for example, a truncated conical narrowing, such that the first end of the connector has the same inner diameter as the tubular insulation. The configuration of the truncated conical narrowing at the end of the first section of the connector pointing towards the inlet end of the reactor tube has a further advantage, namely, that it facilitates the introduction of multi-point thermocouples during installation; the truncated conical narrowing acts as a guiding element for the thermocouples.

[0078] List of reference numerals

[0079] [1] Reformer tube

[0080]

[10] Reactor tube

[0081]

[12] Flange

[0082]

[14] Hat

[0083]

[16] Catalyst tilting bed

[0084]

[18] Feed pipe

[0085]

[20] Measuring equipment (multi-point thermocouple)

[0086]

[22] Fixing devices (e.g., compression fittings)

[0087]

[30] Connector

[0088]

[32] Section 1

[0089]

[33] Flange

[0090]

[34] Second section

[0091]

[35] Feed pipe

[0092]

[36] Transition piece

[0093]

[38] Guide tube

[0094]

[40] Common longitudinal axis of 32, 34, and 36

[0095]

[42] Longitudinal axis of the guide tube

[0096]

[44] Thermal insulation

Claims

1. A connector for connecting a reactor tube to a feed line configured for reactor input flow and for laterally introducing multi-point thermocouples into the reactor tube as a thermal stress compensator, the connector comprising the following components: (a) A first section in the shape of a cylinder or a truncated cone, the first section having a first end pointing toward the circular inlet end of the reactor tube, wherein, The first end of the connector has the same inner diameter as the inlet end of the reactor tube or the tubular insulation introduced into the inlet end of the reactor tube, and wherein the first section of the connector is hermetically connected to the inlet end of the reactor tube. (b) A cylindrical or truncated conical second section having a second end pointing toward the circular discharge end of the feed pipe, wherein the second end of the connector has the same inner diameter as the discharge end of the feed pipe and is capable of being airtightly connected to the discharge end. (c) At least one transition member capable of being hermetically connected to the first and second sections of the connector. (d) wherein these components (a), (b), and (c) have circular cross-sections and longitudinal axes passing through their respective center points, wherein these components are arranged one after the other, their longitudinal axes are aligned and therefore coincide on a common longitudinal axis. (e) A guide tube laterally attached to one of the components (a), (b), and (c), the guide tube being hermetically connected to and leading to the component, and having a fixing device at its end opposite to the component, the fixing device allowing for feedthrough and hermetically secure fixation of the multi-point thermocouple. (f) wherein the angle between the common longitudinal axis and the longitudinal axis of the guide tube is between 15° and 60°, and the angle points in the direction of the feed pipe.

2. The connector according to claim 1, characterized in that, The first section, the second section, the at least one transition piece, and the guide tube, or a combination of these elements, are single-piece or multi-piece but can be airtightly connected, such that all the elements in the connected state are fluidly connected to each other.

3. The connector according to claim 1 or 2, characterized in that, In the connected state, the common longitudinal axis of the connector coincides with the center point of the inlet end of the reactor tube and the center point of the outlet end of the feed pipe.

4. The connector according to claim 1 or 2, characterized in that, The first and / or second section of the connector includes a flange that can be airtightly connected to a flange mating member at the inlet end of the reactor tube and / or the outlet end of the feed pipe.

5. The connector according to claim 1 or 2, characterized in that, The end of the guide tube facing away from the connector includes external thread and pipe thread connectors, extrusion fittings, compression fittings or cutting ring fittings as fixing devices.

6. The connector according to claim 1, characterized in that, The angle between the common longitudinal axis and the longitudinal axis of the guide tube is between 20° and 45°.

7. A measuring device for measuring the axial temperature distribution in a reactor tube, the measuring device comprising: (a) The connector according to any one of claims 1 to 6, (b) Multi-point thermocouples, (c) At least one centering body for centering the multi-point thermocouple in the reactor tube, wherein the centering body comprises: (c1) Inner ring, which allows the feedthrough of the multi-point thermocouple. (c2) A plurality of spacers arranged radially relative to the inner ring and equidistantly along the outer side of the inner ring, wherein the spacers have the same length and the length is selected such that when the centering body is introduced into the reactor tube, the center point of the inner ring coincides with the longitudinal axis of the reactor tube, and the plane formed by the spacers is arranged perpendicular to the longitudinal axis of the reactor tube.

8. The measuring device according to claim 7, used for measuring the axial temperature distribution in a reactor tube filled with a tilted bed of solid particulate catalyst, characterized in that, The average distance between two adjacent spacers is greater than the average length of these catalyst particles.

9. A method for installing the measuring device according to claim 7 or 8 in a reactor tube for performing an endothermic or exothermic multiphase catalytic chemical reaction, the method comprising the steps of: (a) Provide the reactor tube, the measuring device, the feed pipe for the reactor input flow, and the solid particulate catalyst as a loose solid. (b) Pass the multi-point thermocouple through the feed pipe and through the inner rings of at least two centering bodies. (c) Using these centering bodies, the multi-point thermocouple is introduced into the interior of the reactor tube through the inlet end of the reactor tube. (d) The solid particulate catalyst is filled into the interior of the reactor tube through the inlet end until the specified filling height is reached. (e) Connect the connector airtightly to the inlet end of the reactor tube. (f) Connect the connector airtightly to the discharge end of the feed pipe. (g) The multi-point thermocouple is hermetically fixed in the guide tube using the fixing device.

10. The method for installing measuring equipment according to claim 9, characterized in that, (h) Perform the packing of the solid particulate catalyst up to the lower edge of the lowest centering body. (i) Raise the lowest centering body by a specified length along the longitudinal axis of the reactor tube. (j) Repeat steps (h) and (i) until the specified fill height is reached. (k) Remove at least one centering body before connecting the connector to the reactor tube.

11. The method for installing measuring equipment according to claim 9 or 10, characterized in that, The airtight connection between the connector and the inlet end of the reactor tube and / or the airtight connection between the connector and the outlet end of the feed pipe is performed using flange connections and / or welded connections.

12. The method for installing measuring equipment according to claim 9, characterized in that, In step (b), the multi-point thermocouple is passed through the feed pipe and through the inner ring of at least three centering bodies.

13. Use of a connector according to any one of claims 1 to 6 and / or a measuring device according to claim 7 or 8 for measuring the axial temperature distribution in a reformer tube for steam reforming of hydrocarbons.

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