Method for installing thermocouples inside the reaction tube of a tubular reactor.

Abstract

A method for installing a thermocouple (500) in a reactor tube (8) of a tubular reactor (1), comprising the steps of lowering a weighted tow line (510) through a stack of catalyst carriers (10), and using a tow line (512) to pull the thermocouple (500) through an internal channel of the stack of catalyst carriers (10), along the reactor tube, and into a desired installation location.

Description

Technical Field

[0001] The present disclosure relates to improvements in or relating to thermocouples for tubular reactors. In particular, it relates to methods of installing thermocouples within the reaction tubes of tubular reactors, as well as related components, methods, and assemblies.

Background Art

[0002] Conventional so-called fixed-bed tubular reactors are typically cylindrical and usually comprise a reactor shell containing a plurality of tubes directly filled with catalyst particles. In use, a heat transfer medium flows through the shell of the reactor outside these tubes, thereby regulating the temperature of the catalyst within the tubes by heat exchange across the tube walls. Thus, if the reaction is an exothermic reaction, the heat transfer medium enables heat to be removed from the catalyst, and if the reaction is an endothermic reaction, the heat transfer medium provides heat to the catalyst.

[0003] For some reactions, the thermal effect of the reaction is moderate such that either they do not pose a problem or they can be easily managed. In some cases, the thermal effect is sufficiently small that large-diameter tubes may be used. This has the advantage of having a large amount of catalyst present within the tubes.

[0004] However, for more exothermic or endothermic reactions, efficient heat transfer to the heat transfer medium through the tube walls is required to maintain stable operating temperatures and control the conditions within the reactor to avoid the occurrence of harmful effects. In the case of exothermic reactions, such effects can include the occurrence of side reactions, damage to the catalyst due to sintering of catalytic active sites, and in the worst case, thermal runaway. Harmful effects for endothermic reactions can include deactivation of the reaction.

[0005] To achieve the desired efficiency, the surface area of ​​the tube wall per unit length must be maximized. In the past, this has been achieved by installing a larger number of smaller diameter tubes. In some reactions, size limitations mean that the tubes have an inner diameter of only about 15-40 mm. However, the use of this large number of tubes increases the cost and complexity of the reactor.

[0006] Therefore, in attempts to mitigate these problems, alternative approaches have been developed, particularly for more exothermic or endothermic reactions, in which the catalyst is not directly packed into the reaction tube, but instead is housed in multiple catalyst carriers configured to be located within the reaction tube.

[0007] A first type of such catalyst carrier is described in International Publication No. 2011 / 048361. This arrangement seeks to optimize heat transfer in the tube wall so that larger tubes and smaller catalyst particles of a larger volume can be used for more exothermic or even endothermic reactions. The catalyst carrier described in International Publication No. 2011 / 048361 comprises an annular container for holding the catalyst when in use. The container has a perforated inner wall defining the tube, a perforated outer wall, an upper surface closing the annular container, and a bottom surface closing the annular container. The surface closing the bottom of the tube is formed by the inner wall of the annular container. The skirt portion extends upward from the perforated outer wall of the annular container to a position below the location of the seal portion, from the bottom surface of the container or a position near thereto. The seal portion is located on or near the upper surface and extends from the container by a distance that extends beyond the outer surface of the skirt portion.

[0008] A second type of such catalyst carrier is described in International Publication No. 2012 / 136971. In this arrangement, the catalyst carrier comprises a container for holding a monolithic catalyst when in use, the container having a bottom surface that closes the container and a skirt portion that extends upward from the bottom surface of the container to a position below the location of the sealing portion and is positioned at a distance therefrom, the skirt portion being positioned such that there is a space between the outer surface of the monolithic catalyst and the skirt portion, the sealing portion being located on or near the upper surface of the monolithic catalyst and extending by a distance that extends from the monolithic catalyst beyond the outer surface of the skirt portion.

[0009] A third type of such catalyst carrier is described in International Publication No. 2016 / 050520. In this configuration, the catalyst carrier comprises a container for holding the catalyst when in use. The container has a bottom surface that closes the container and an upper surface. The outer wall of the carrier extends from the bottom surface to the upper surface, and the sealing portion extends from the container by a distance that extends beyond the outer wall of the carrier. The outer wall of the carrier has an opening located below the sealing portion.

[0010] Monitoring the temperature inside the reactor tube may be important for monitoring the operation of a tubular reactor. Publication No. 2524865 of a British Patent Application describes the use of multipoint thermocouples that can be positioned along the center of multiple catalyst carriers within a reaction tube when the flow of the reaction gas is in the "reverse direction," i.e., from the bottom of the reaction tube towards the top of the reaction tube.

[0011] However, placing thermocouples inside reaction tubes can be difficult and time-consuming. Individual reactor tubes may contain up to 60 or more catalyst carriers, which can make thermocouple installation particularly cumbersome. The cost of reactor downtime is considerable. Therefore, it is desirable to provide an improved method for installing thermocouples inside reaction tubes of tubular reactors.

[0012] Furthermore, placing thermocouples inside the reaction tube may cause disturbances in the gaseous and / or liquid flow of the reactants and products within the tube. Therefore, it is desirable to provide an improved method that at least partially mitigates such disturbances. [Overview of the project]

[0013] A first aspect of this disclosure provides a method for installing thermocouples inside the reaction tube of a tubular reactor, the method being described as follows: i) A step of providing a stack of catalyst carriers in the reaction tube of a tubular reactor, wherein each catalyst carrier has an internal channel extending from the top to the bottom of the catalyst carrier, ii) A step of providing a towing line with a weight, comprising a weight and a towing line following the weight, iii) The step of inserting a weight into the upper part of the reaction tube and into the internal channel of the catalyst carrier at the top of the stack, iv) The process of lowering the weighted traction line under gravity through the internal channels of the uppermost catalyst carriers, and then through the internal channels of each of the remaining catalyst carriers in the stack, until the weighted traction line emerges from the bottom of the reaction tube. v) The process of attaching the thermocouple to the rear end of the traction line, vi) A step of engaging a thermocouple into the upper part of the reaction tube within the internal channel of the catalyst carrier at the top of the stack, vii) The process includes pulling a traction line from the bottom of the reaction tube and pulling a thermocouple along the reaction tube through an internal channel of the catalyst carrier stack into a desired installation position for the thermocouple.

[0014] A second aspect of the present disclosure provides a thermocouple comprising one or more thermocouple assemblies, an outer sheath covering one or more thermocouple assemblies, and a tip portion configured to be attached to a traction line.

[0015] A third aspect of this disclosure provides a component kit for installing thermocouples inside the reaction tube of a tubular reactor, the component kit includes, a) A thermocouple comprising one or more thermocouple assemblies, an outer sheath covering one or more thermocouple assemblies, and a tip portion, b) A towing line with a weight, comprising a weight and a towing line following the weight.

[0016] Advantageously, the use of weighted traction lines improves the ease and speed of installing thermocouples within the reaction tube, leading to a reduction in the downtime of the tubular reactor.

[0017] In step iv) of the first embodiment, the weighted traction line may pass through each of the exhaust holes of the catalyst carrier. The exhaust holes of the catalyst carrier may be sized to simultaneously function as conduits for thermocouples and exhausts for the stack of catalyst carriers. In some embodiments, each exhaust hole has an inner diameter of 3.0 to 10.0 mm, optionally 5.0 to 6.5 mm, and optionally 5.2 to 5.8 mm. Advantageously, by using the exhaust holes to conduct thermocouples, it is not necessary to provide additional openings in the catalyst carrier. Thus, disturbances to the gas and liquid flows through the catalyst carrier can be minimized. In addition, the size of the exhaust holes may be such that they continue to function effectively as exhausts for the catalyst carrier while simultaneously providing passages for thermocouples. In this case as well, disturbances to the gas and liquid flows through the catalyst carrier can be minimized.

[0018] The catalyst carrier discharge holes may be aligned on the same axis. This axis may be a vertical axis or it may coincide with the longitudinal central axis of the reaction tube.

[0019] The weight may be configured to have a length longer than the length of one catalyst carrier, preferably longer than the length of two catalyst carriers, and preferably longer than the length of three catalyst carriers. In step iii) of the first embodiment, the weight may be inserted into the internal channel of the uppermost one catalyst carrier, preferably the uppermost two catalyst carriers, and preferably the uppermost three catalyst carriers. Advantageously, this may allow for easier alignment of the weighted traction line with the internal channel of the catalyst carrier. Furthermore, this may significantly reduce the possibility of the weighted traction line deviating from the centerline of the tubular reactor and becoming entangled on the surface of the catalyst carrier. The weight may be appropriately fabricated from a high-density material, typically a metal such as steel, so as to be heavy enough to pull the traction line through the catalyst carrier.

[0020] The towing line may be any flexible wire or cable. The towing line may be made from any suitable material that has the strength necessary to support the weight and to pull the thermocouple through the catalyst carrier without breaking under tension. For example, the towing wire may be a steel wire.

[0021] The thermocouple may be configured to have a tip portion for insertion assistance. The tip portion may have a length longer than the length of one catalyst carrier, optionally longer than the length of two catalyst carriers, and optionally longer than the length of three catalyst carriers. In step vi) of the first embodiment, the tip portion of the thermocouple may be supplied into the internal channels of the uppermost one catalyst carrier, optionally the uppermost two catalyst carriers, and optionally the uppermost three catalyst carriers.

[0022] The tip portion may include a solid member, a hollow tubular member, or a mixture thereof. The tip portion may be formed from a metal such as carbon steel, aluminum, stainless steel, or other suitable alloy that can withstand the reaction conditions.

[0023] The distal portion may extend distally from the distal end of the thermocouple, for example, from one or more thermocouple assemblies.

[0024] The distal portion may be rigid.

[0025] The distal portion may comprise a tapered tip and a straight section.

[0026] The thermocouple may be attached to the rear end of the traction line by joining the rear end portion to the distal portion of the thermocouple.

[0027] The distal portion may comprise a tubular portion, and the rear end portion of the traction line may be attached into the tubular portion. The traction line may be attached by any suitable means including, but not limited to, adhesives, soldering, welding, crimping / expanding of tubular components, plugging of tubular components with plugs for capturing the rear end portion, etc.

[0028] In step vii) of the first aspect, the method may further comprise attaching the traction line to a winding device and pulling the traction line by winding up the winding device. The winding device may be an electric or manual winding device.

[0029] In step v) of the first aspect, the thermocouple may be attached to the rear end portion of the traction line before the weighted traction line is inserted into the reaction tube or after the weighted traction line emerges from the bottom of the reaction tube.

[0030] After the weighted traction line emerges from the bottom of the reaction tube, the weight may be removed from the traction line. The weight may be removed, for example, by cutting the traction line.

[0031] After the thermocouple reaches its desired installation position, the traction line may be removed from the thermocouple. The traction line may be removed from the thermocouple, for example, by cutting the traction line.

[0032] The parts kit may further include a winding device for winding up the tow line.

[0033] The component kit may further comprise multiple catalyst carriers, each of which may have an internal channel extending from the top to the bottom of the catalyst carrier.

[0034] Each catalyst carrier may be provided with a discharge hole at its bottom, and the size of the discharge hole may be determined to accommodate the passage of weights, traction lines, and thermocouples.

[0035] The discharge holes may be located on the central axis of the internal channels of each catalyst carrier.

[0036] Each catalyst carrier's internal channel may be equipped with a funnel portion for guiding a weight and thermocouple toward the discharge port.

[0037] A fourth aspect of this disclosure includes an assembly comprising a tubular reactor, a catalyst carrier, and a plurality of multipoint thermocouples. A tubular reactor equipped with multiple reaction tubes, Each of the multiple reaction tubes containing multiple catalyst carriers, and the first reaction tube among the multiple reaction tubes, further comprising a first multipoint thermocouple connected and passed through the inside of the catalyst carriers housed in the first reaction tube, A second reaction tube is provided, which is one of a plurality of reaction tubes, and further comprises a second multipoint thermocouple connected to and passed through the interior of a catalyst carrier housed within the second reaction tube. The temperature sensor of the first multipoint thermocouple is positioned to read the temperature within a first portion of the length of the tubular reactor, and the temperature sensor of the second multipoint thermocouple is positioned to read the temperature within a second portion of the length of the tubular reactor.

[0038] The first and second parts do not have to overlap, or do not have to overlap significantly. For example, the first part may be the upper 50% to 60% of the length of the reaction tube, and the second part may be the lower 50% to 60% of the length of the reaction tube.

[0039] The assembly may further comprise a third reaction tube among a plurality of reaction tubes, and further comprise a third multipoint thermocouple connected and passed through the inside of a catalyst carrier housed in the third reaction tube. A third multi-point thermocouple temperature sensor is positioned to read the temperature within a third portion of the length of the tubular reactor.

[0040] The first, second, and third parts do not have to overlap, or do not have to overlap significantly. For example, the first part may be the upper 33% to 40% of the length of the reaction tube, the second part may be the middle 33% to 40% of the length of the reaction tube, and the third part may be the lower 33% to 40% of the length of the reaction tube.

[0041] Each catalyst carrier in the reaction tube without a multi-point thermocouple may have an outlet with a first inner diameter, and each catalyst carrier in the reaction tube with a multi-point thermocouple may have an outlet with a second inner diameter larger than the first diameter.

[0042] For example, the first diameter may be 2.5 to 3.5 mm, or 3.0 mm if desired, and the second diameter may be 3.0 to 10.0 mm, or 5.0 to 6.5 mm, or 5.2 to 5.8 mm if desired.

[0043] A fifth aspect of this disclosure includes an assembly comprising a tubular reactor, a catalyst carrier, and one or more thermocouples. A tubular reactor equipped with multiple reaction tubes, Each of the multiple reaction tubes containing multiple catalyst carriers, A reaction tube is provided, comprising one or more selected reaction tubes from a plurality of reaction tubes, further comprising thermocouples connected and passed through the interior of catalyst carriers housed within the reaction tubes. Each catalyst carrier in the reaction tube without a thermocouple is provided with a discharge port of a first inner diameter, and each catalyst carrier in the reaction tube with a thermocouple is provided with a discharge port of a second inner diameter larger than the first diameter.

[0044] The first diameter is 2.5 to 3.5 mm, and may be 3.0 mm if desired, and the second diameter is 3.0 to 10.0 mm, and may be 5.0 to 6.5 mm, 5.2 to 5.8 mm, or 5.6 mm if desired.

[0045] This method and related components and assemblies may be usefully used in a wide range of processes. Examples of preferred applications include processes and reactors for exothermic reactions such as reactions for the production of methanol, reactions for the production of ammonia, methanation reactions, shift reactions, oxidation reactions such as the formation of maleic anhydride, and ethylene oxide reactions. Particularly preferred applications are processes and reactors for carrying out the Fischer-Tropsch reaction.

[0046] Endothermic reactions such as pre-reforming and dehydrogenation may also be carried out in conjunction with this method and related components and assemblies.

[0047] The catalyst carrier of this disclosure may be filled or partially filled with any catalyst suitable for the intended reaction. For example, a Fischer-Tropsch catalyst may be used in a Fischer-Tropsch reaction. A cobalt-containing Fischer-Tropsch catalyst is preferred. The catalyst may be provided as catalyst particles or a catalyst monolith. The catalyst may be provided as a single catalyst bed or as a plurality of catalyst beds. The catalyst carrier may be configured to promote axial and / or radial flow through the catalyst. In some embodiments, the catalyst carrier may be configured to preferentially promote radial flow through the catalyst.

[0048] The catalyst carriers of this disclosure may be formed from any suitable material. Such materials are generally selected to withstand the operating conditions of a tubular reactor. The catalyst carriers may be made from carbon steel, aluminum, stainless steel, other alloys, or any material that can withstand the reaction conditions. [Brief explanation of the drawing]

[0049] Next, embodiments of the present disclosure will be described only as examples with reference to the attached drawings.

[0050] [Figure 1] This is a schematic diagram of a tubular reactor. [Figure 2] This is an enlarged view of Figure 1. [Figure 3] This is another enlarged section of Figure 1. [Figure 4] This is a schematic diagram of an assembly consisting of a weighted traction line and a thermocouple. [Figure 5] Figure 4 is a side view of the weight in the weighted towing line. [Figure 6] Figure 4 is a perspective view of a portion of the assembly showing the mounting between the weight and the tow line. [Figure 7] Figure 4 is a perspective view of a portion of the assembly showing the mounting between the traction line and the thermocouple. [Figure 8] This is a cross-sectional view of the catalyst carrier. [Figure 9] Figure 8 is a perspective view of the decomposed catalyst carriers. [Figure 10] Figure 8 is a perspective view of the catalyst carrier. [Modes for carrying out the invention]

[0051] In the following, aspects and embodiments of the present disclosure will be described only as examples, with reference to a vertically oriented tubular reactor having a plurality of vertical reaction tubes extending between an upper tube sheet and a lower tube sheet. However, it will be understood that the present disclosure may also apply to other configurations of tubular reactors that may employ other orientations.

[0052] Furthermore, in this specification, references to orientations such as top, bottom, upper side, lower side, upward, downward, etc., are used in relation to the orientation of parts as shown in the referenced drawings, but should not be considered to limit the potential orientation of such parts in actual use.

[0053] Figure 1 shows a typical layout of a tubular reactor 1 of the present disclosure. The tubular reactor 1 includes a housing 2. The interior of the housing may be divided into a head space 3, a heat exchange compartment 4, and a footer space 5 by two tube sheets, namely an upper tube sheet 6 and a lower tube sheet 7. The upper tube sheet 6 separates the head space 3 from the heat exchange compartment 4. The lower tube sheet 7 separates the footer space 5 from the heat exchange compartment 4.

[0054] Multiple reaction tubes 8 extend between the upper tube sheet 6 and the lower tube sheet 7. A large number of reaction tubes 8 may be provided, for example, 20 to 5000 reaction tubes 8 may be present. Each reaction tube 8 may have an inner diameter of, for example, 20 to 150 mm. In some embodiments, the inner diameter may be approximately 85 mm.

[0055] Each reaction tube 8 is intended to be filled, or substantially filled, with a stacked arrangement of catalyst carriers 10. Examples of preferred catalyst carriers 10 are shown in Figures 8-10. In particular, it is typically desirable that the catalyst carriers 10 cover all or substantially all of the length of the reaction tube 8 between the upper tube sheet 6 and the lower tube sheet 7, i.e., all or substantially all of the length of the heat exchange compartment 4. Each catalyst carrier 10 has internal channels (not shown).

[0056] The head space 3 may provide access to the upper end of the reaction tube 8 to allow loading of the catalyst carrier 10 into the reaction tube 8. The footer space 5 may provide access to the lower end of the reaction tube 8 to allow removal of the catalyst carrier 10 from the reaction tube 8.

[0057] The tubular reactor 1 may be equipped with one or more thermocouples 500, as shown in Figures 1 to 3. Each thermocouple 500 may be a multi-point thermocouple. For example, each thermocouple 500 may be equipped with one or more thermocouple assemblies 501 and an outer sheath 502 covering one or more thermocouple assemblies 501, as shown in Figure 7. Each thermocouple assembly 501 may be equipped with at least one temperature sensing point 503.

[0058] A weighted traction line 510 may be provided to install each thermocouple 500 into the tubular reactor 1. The weighted traction line 510 may include a weight 511 and a traction line 512 following the weight 511, as shown in Figure 4.

[0059] As shown in Figures 5 and 6, the weight 511 may have an elongated body 515 that may be linear. The elongated body 515 may have a tapered tip 516 at its distal end. The elongated body 515 may have a tubular section 513 at its proximal end opposite the tapered tip 516. In addition to the tubular section 513, the weight 511 may be solid. The weight 511 may be rigid and may be made of, for example, stainless steel.

[0060] The weight 511 may have a length longer than the length of one catalyst carrier 10, and optionally longer than the length of two or three catalyst carriers 10. The weight 511 may have a length greater than 200 mm, optionally greater than 300 mm, and optionally greater than 400 mm. The tapered tip portion 516 may have a length of about 50 mm.

[0061] As shown in Figure 6, the tubular section 513 may define a hole 514 for receiving the end of the traction line 512. The traction line 512 may be attached to the weight 511, for example, by crimping / stretching the tubular section 513 to grip the traction line 512. Other attachment methods may be used, for example, adhesive, soldering, or screw fastening or push-fit.

[0062] As shown in Figure 7, the thermocouple 500 may also include a tip portion 520 configured to be attached to a traction line 512. The tip portion 520 may extend distally from the distal end of one or more thermocouple assemblies 501. The tip portion 520 may include a tubular section 521 that can define a hole 522 for receiving the end of the traction line 512. The traction line 512 may be attached to the thermocouple by, for example, crimping / stretching the tubular section 521 to grip the traction line 512. Other attachment means may be used, for example, adhesive, soldering, or screw or push-fit attachment.

[0063] The tip portion 520 may have a tapered tip portion 523.

[0064] The tip portion 520 may have a length longer than the length of one catalyst carrier 10, and optionally, a length longer than the length of two or three catalyst carriers 10. The tapered tip portion 523 may have a length of approximately 50 mm.

[0065] The traction line 512 may be formed from a suitable material. It may be, for example, a steel wire. The wire may have a thickness of, for example, about 1.2 mm.

[0066] When in use, the thermocouple 500 may first be installed in the reaction tube of the tubular reactor 1 by inserting the weight 511 of the weighted traction line 510 into the upper part of the reaction tube 8 and into the internal channel of the uppermost catalyst carrier 10. The weighted traction line 510 may be lowered, descended, or otherwise supplied under gravity through the internal channel of the uppermost catalyst carrier 10 until the weighted traction line 510 emerges from the bottom of the reaction tube 8, and then through the internal channels of each of the remaining catalyst carriers 10 in the stack.

[0067] At this point, if necessary, the weight 511 may be removed from the tow line 512, for example, by cutting it.

[0068] The thermocouple 500 is attached to the rear end of the traction line 512. The attachment may be performed after or before the traction line 512 is supplied through the reaction tube 8.

[0069] Next, the thermocouple 500 is engaged with the top of the reaction tube 8 in the internal channel of the catalyst carrier 10 at the top of the stack, and the traction line 512 is pulled from below the reaction tube 8, pulling the thermocouple 500 along the reaction tube 8 through the internal channel of the stack of catalyst carrier 10.

[0070] The traction line 512 may be pulled manually or mechanically, and preferably it may be wound up by a winding device to be pulled along the reaction tube 8.

[0071] Once the thermocouple 500 is positioned in the desired location, the traction line 512 may be removed from the thermocouple 500, for example, by cutting it.

[0072] During installation, the weighted towing line 510 may pass through discharge holes communicating with each internal channel of the catalyst carrier 10. In some embodiments, each discharge hole has an inner diameter of 3.0 to 10.0 mm, optionally 5.0 to 6.5 mm, and optionally 5.2 to 5.8 mm. The outer sheath 502 may have an outer diameter of 1.0 to 6.4 mm.

[0073] The discharge holes may be located at the bottom of the catalyst carrier 10 and may be sized to accommodate the passage of the weight 511, the traction line 512, and the thermocouple 500.

[0074] The discharge holes may be located on the central axis of the internal channels of each catalyst carrier 10.

[0075] The internal channels of each catalyst carrier 10 may be provided with a funnel portion for guiding the weight 511 and thermocouple 500 toward the discharge port.

[0076] The tubular reactor 1 may be equipped with multiple thermocouples 500. Each thermocouple 500 may be installed in a different reaction tube 8. Two or more sets of thermocouples 500 may be used to monitor the temperature of different sections of the tubular reactor 1. For example, as shown in Figures 2 and 3, three thermocouples 500a, 500b, and 500c may be installed in three different reaction tubes 8. Thermocouple 500a may be used to monitor the temperature of the bottom portion of the tubular reactor 1, for example, the bottom third of the tubular reactor 1. Thermocouple 500b may be used to monitor the temperature of the middle portion of the tubular reactor 1, for example, the middle third of the tubular reactor 1. Thermocouple 500c may be used to monitor the temperature of the upper portion of the tubular reactor 1, for example, the upper third of the tubular reactor 1. The catalyst carrier positions may overlap along the tubes monitored by thermocouples 500a to 500c.

[0077] Beneficially, using a set of thermocouples 500 to monitor the overall length of the tubular reactor 1 allows for a reduction in the outer diameter of each individual thermocouple 500 (by limiting the number of thermocouple assemblies 501 within each outer sheath 502). This may improve the loading rate through the internal channels and discharge holes of each catalyst carrier 10.

[0078] Examples of the catalyst carrier 10 according to this disclosure, which may be used with thermocouple 500, are shown in Figures 8 to 10 as an example. However, it will be understood from this disclosure that the catalyst carrier 10 can take various forms. For example, as with the examples described herein, the catalyst carrier 10 may take other forms, including but not limited to those disclosed in International Publication Nos. 2011 / 048361, 2012 / 136971, and 2016 / 050520, the contents of which are incorporated herein by reference in their entirety.

[0079] The catalyst carrier 10 may include a container sized to be smaller than the internal dimensions of the reaction tube 8 in which it is placed during use. Typically, the sealing portion is sized to interact with the inner wall of the reaction tube 8 when the catalyst carrier 10 is in a predetermined position within the reaction tube 8. Parameters such as the length and diameter of the carrier may be selected to suit different reactions and configurations of the reaction tube 8.

[0080] As shown in Figures 8 to 10, the catalyst carrier 10 may include a container 100 for holding the catalyst during use. The container 100 may generally have a bottom surface 101 that closes the lower end of the container 100 and an upper surface 102 at the upper end of the container 100. The carrier outer wall 103 may extend from the bottom surface 101 to the upper surface 102. The sealing portion 104 may extend from the container 100 by a distance beyond the carrier outer wall 103. The carrier outer wall 103 may have an opening 105 located below the sealing portion 104.

[0081] As shown in Figure 8, in at least some embodiments, the catalyst carrier 10 may more specifically include an annular container 110 for holding the catalyst during use. The annular container 110 may include a perforated inner container wall 111 defining an internal channel 112, and a perforated outer container wall 113 which may be arranged concentrically around the perforated inner container wall 111. An annular upper surface 114 may close the upper end of the annular container 110, and an annular bottom surface 115 may close the lower end of the annular container 110. The lower end of the internal channel 112 may be closed by a channel end surface 116, except for one or more discharge openings (not shown) which may be provided at the lower end of the internal channel 112. The channel end surface 116 may be formed integrally with or separately from the inner container wall 111.

[0082] As shown in the exploded view of Figure 9, the catalyst carrier 10 may be formed from a number of individual components that can be assembled together by any preferred means, including welding, for example. In some embodiments, such components may include a perforated inner tube 120, a perforated intermediate tube 121, an outer tube 122, a bottom cap 123, an annular upper ring 124, an upper cap 125, and an annular sealing ring 126.

[0083] The catalyst carrier 10 may be formed from any suitable material. Such materials are generally selected to withstand the operating conditions of the reactor. Generally, the catalyst carrier is made from carbon steel, aluminum, stainless steel, other alloys, or any material that can withstand the reaction conditions.

[0084] The appropriate thickness of the components is approximately 0.1 mm to 1.0 mm, preferably approximately 0.3 mm to 1.0 mm.

[0085] The perforated inner tube 120 may include a perforated inner container wall 111. The perforated intermediate tube 121 may include a perforated outer container wall 113. The outer tube 122 may include a carrier outer wall 103 and define an opening 105. The bottom cap 123 may include a bottom surface 101 and / or an annular bottom surface 115. The bottom cap 123 may also extend across the perforated inner tube 120 to include a channel end surface 116. The annular upper ring 124 and upper cap 125 may include an annular upper surface 114 and at least a portion of the upper surface 102. The annular sealing ring 126 may include a sealing portion 104.

[0086] The size of the perforations in the perforated inner tube 120 and the perforated intermediate tube 121 is selected to allow a uniform flow of reactants and products through the catalyst while keeping the catalyst within the annular vessel 110. Therefore, it will be understood that their sizes depend on the size of the catalyst particles used. Alternatively, the perforations may be larger, but with a filter mesh covering the perforations to ensure the catalyst is kept within the annular vessel 110.

[0087] It will be understood that the perforation may be of any preferred configuration. In fact, when it is stated that a wall or tube is perforated, the only requirement is that there are means to allow the reactants and products to pass through the wall or tube.

[0088] The bottom surface 101, for example, the bottom cap 123, may be molded to engage with the upper end of another catalyst carrier 10. Advantageously, engagement of adjacent catalyst carriers 10 may facilitate precise alignment of the catalyst carriers 10. In particular, it may help ensure that the longitudinal axes of the catalyst carriers 10 substantially coincide, which may advantageously facilitate the passage of the weighted traction line 510 and / or thermocouple 500 through the internal channel 112 and exhaust hole of the catalyst carrier 10. For example, the bottom surface 101 may have an annular recess 130 around a perforated inner tube 120. The top cap 125 may be molded to engage with the annular recess 130 of another catalyst carrier 10. For example, the top cap 125 may have an annular ring 131 erected from an annular plug body 132. The annular ring 131 may be shaped and sized to be received within the annular recess 130.

[0089] The bottom surface 101, for example, the bottom cap 123 and / or the channel end surface 116, may include one or more discharge holes.

[0090] The annular upper ring 124 may be shaped and sized to engage with the upper end of the outer tube 122. The annular plug body 132 of the upper cap 125 may have an outer diameter configured to engage with the central opening of the annular upper ring 124. The engagement between the upper cap 125 and the annular upper ring 124 may function to hold the annular sealing ring 126 in place.

[0091] The upper cap 125 may have a central inlet 134 within the annular plug body 132 to allow liquids and gases to enter the upper end of the internal channel 112. The annular ring 131 may have a lateral opening 133 to allow liquids and gases to reach the central inlet 134.

[0092] The carrier outer wall 103 may be smooth or molded. Preferred shapes include pleated or wavy shapes.

[0093] The opening 105 in the carrier outer wall 103 may have any configuration. In some embodiments, the opening 105 may be a hole or a slot.

[0094] The sealing portion 104 may be formed in any preferred manner. However, it is generally sufficiently compressible to accommodate the minimum diameter of the reaction tube 8. The sealing portion 104 is generally a flexible sliding seal. In some embodiments, the sealing portion 104 may include a deformable flange 140 extending from the carrier outer wall 103 or the upper surface 102 of the catalyst carrier 10. The flange 140 may be larger than the inner diameter of the reaction tube 8 so as to deform to fit inside the reaction tube 8 and interact with the reaction tube 8 when the catalyst carrier 10 is inserted into the reaction tube 8.

[0095] In the illustrated embodiment of Figure 8, the deformable flange 140 includes the outer portion of the annular sealing ring 126. The inner portion 141 of the annular sealing ring 126 may define a clamping surface that is held between the upper cap 125 and the annular upper ring 124. The deformable flange 140 may be angled relative to the inner portion 141. The deformable flange 140 may be angled toward the upper end of the catalyst carrier 10.

[0096] The carrier outer wall 103 may extend above the sealing portion 104. Therefore, the sealing portion 104 may be located on the upper part of the catalyst carrier 10, optionally as part of the upper surface 102, or at a suitable point on the carrier outer wall 103 if it is located above the opening 105 of the carrier outer wall 103.

Claims

1. A method for installing thermocouples inside the reaction tube of a tubular reactor, The method described above is i) A step of providing a stack of catalyst carriers in the reaction tube of the tubular reactor, wherein each catalyst carrier has an internal channel extending from the top to the bottom of the catalyst carrier; ii) A step of providing a weighted traction line comprising a weight and a traction line following the weight, wherein the weight is configured to have a length longer than the length of one catalyst carrier. iii) The step of inserting the weight into the upper part of the reaction tube and into the internal channel of the catalyst carrier at the top of the stack, iv) The step of lowering the weighted traction line under gravity through the internal channels of the uppermost catalyst carrier, and then through the internal channels of each of the remaining catalyst carriers in the stack, until the weighted traction line emerges from the bottom of the reaction tube. v) The step of attaching the thermocouple to the rear end of the traction line, vi) The step of inserting the thermocouple into the upper part of the reaction tube and into the internal channel of the uppermost catalyst carrier of the stack, vii) A step of pulling the traction line from below the reaction tube to pull the thermocouple through the internal channel of the stack of catalyst carriers along the reaction tube into a desired installation position for the thermocouple, A method that includes performing the following in this order.

2. The method according to claim 1, wherein in step iv), the weighted traction line passes through each of the discharge holes of the catalyst carrier.

3. The method according to claim 1 or 2, wherein the weight is configured to have a length longer than the length of the two catalyst carriers, and in step iii), the weight is inserted into the internal channels of the two uppermost catalyst carriers.

4. The method according to any one of claims 1 to 3, wherein the thermocouple is configured to have a tip portion having a length longer than the length of one catalyst carrier, and in step vi), the tip portion of the thermocouple is supplied into the internal channel of the uppermost catalyst carrier.

5. The method according to claim 4, wherein the tip portion includes a tapered tip portion and a linear portion.

6. The method according to claim 4 or 5, wherein the thermocouple is attached to the rear end of the traction line by joining its rear end to the front end of the thermocouple.

7. The method according to any one of claims 1 to 6, wherein in step v), the thermocouple is attached to the rear end of the traction line before the weighted traction line is inserted into the reaction tube, or after the weighted traction line emerges from the bottom of the reaction tube.

8. The method according to any one of claims 1 to 7, wherein the weight is removed from the traction line after the weighted traction line has emerged from the bottom of the reaction tube, or the traction line is removed from the thermocouple after the thermocouple has reached its desired installation position.

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