IMPROVEMENTS IN OR RELATING TO CATALYST CARRIERS FOR TUBULAR REACTORS AND ASSOCATED METHODS

Abstract

A catalyst carrier for insertion into a reactor tube of a tubular reactor comprises a container for holding catalyst and a seal for sealing between the container and the reactor tube. The seal comprises at least a first seal layer and a second seal layer each comprising a plurality of deflectable tongues separated by notches. The second seal layer is rotationally offset relative to the first seal layer such that the notches of the second seal layer are aligned with the deflectable tongues of the first seal layer.

Claims

1. A catalyst carrier for insertion into a reactor tube of a tubular reactor, the catalyst carrier comprising a container for holding catalyst in use and a seal for sealing between the container and an inner surface of the reactor tube; the catalyst carrier having a longitudinal axis that in use can be aligned with a longitudinal axis of the reactor tube to facilitate installation of the catalyst carrier into the reactor tube; wherein the seal comprises at least a first seal layer and a second seal layer; the first seal layer and the second seal layer each comprising a plurality of deflectable tongues separated by notches; the second seal layer being rotationally offset about the longitudinal axis of the catalyst carrier relative to the first seal layer such that the notches of the second seal layer are aligned with the deflectable tongues of the first seal layer.

2. The catalyst carrier of claim 1, wherein the first seal layer and the second seal layer overlie each other; optionally in face-to-face contact.

3. The catalyst carrier of claim 1, wherein the first seal layer and the second seal layer comprise separate sealing elements.

4. The catalyst carrier of claim 1, wherein the first seal layer and the second seal layer comprise first and second portions of an integral sealing element; and optionally wherein the integral sealing element is a helical element.

5. The catalyst carrier of claim 1, wherein each of the first seal layer and the second seal layer comprise a notched outer edge forming its plurality of deflectable tongues.

6. The catalyst carrier of claim 1, wherein the notches comprise side walls that are parallel or diverge towards an outer edge of the respective seal layer; and optionally wherein the notches are U-shaped or V-shaped.

7. The catalyst carrier of claim 1, wherein the first seal layer and the second seal layer extend perpendicularly from the container.

8. The catalyst carrier of claim 1, wherein at least a distal end of the tongues of the first seal layer and the second seal layer are angled towards an end of the container.

9. The catalyst carrier of claim 1, wherein each of the first seal layer and the second seal layer comprise an annular element.

10. The catalyst carrier of claim 1, comprising three or more seal layers each comprising a plurality of deflectable tongues separated by notches; each seal layer being rotationally offset about the longitudinal axis of the catalyst carrier relative to at least one of the other seal layers such that the notches of each seal layer are aligned with the deflectable tongues of at least one of the other seal layers; and optionally wherein the notches of each seal layer are aligned with the deflectable tongues of one or both adjacent seal layers.

11. The catalyst carrier of claim 10, wherein the catalyst carrier comprises four, five or six seal layers.

12. The catalyst carrier of claim 1, wherein an inner edge of the one or more seal layers are attached together.

13. The catalyst carrier of claim 1, wherein each seal layer comprises a key or keyway for engaging a complementary keyway or key on the container for maintaining relative rotational alignment of the seal layers with each other.

14. The catalyst carrier of claim 1, wherein each container comprises a bottom surface at the lower end, a top surface at the upper end, and a carrier outer wall extending between the bottom surface to the top surface.

15. The catalyst carrier of claim 14, wherein the seal layers are attached to the carrier outer wall and or the top surface.

16. The catalyst carrier of claim 14, wherein the carrier outer wall comprises a plurality of apertures and the seal layers are attached to the carrier wall above the plurality of apertures.

17. The catalyst carrier of claim 1, wherein each container further comprises an annular chamber for holding catalyst in use, said annular chamber having a perforated inner chamber wall defining an inner channel, a perforated outer chamber wall, a top surface closing the annular chamber and a bottom surface closing the annular chamber.

18. The catalyst carrier of claim 1, wherein the thickness of the first seal layer and the second seal layer are different.

19. The catalyst carrier of claim 1, wherein the material of the first seal layer and the second seal layer are different.

20. The catalyst carrier of claim 1, wherein the shape of the notches of the first seal layer and the second seal layer are different.

21. A method of installing a catalyst carrier into a reactor tube of a tubular reactor, the method comprising the steps of: i) providing an installation tool comprising a movable ram configured for pushing the catalyst carrier into the reactor tube; ii) using the movable ram to push the catalyst carrier into the reactor tube such that a container of the catalyst carrier is received within the reactor tube; and iii) pushing the catalyst carrier into the reactor tube causes a seal of the catalyst carrier to contact and be deformed by an inner surface of the reactor tube and at least a first seal layer and a second seal layer of the seal are deformed by the contact of the seal with the inner surface.

22. The method of claim 21, wherein the first seal layer and the second seal layer both comprise a plurality of notches and pushing the catalyst carrier into the reactor tube causes the notches to at least partially close.

23. The method of claim 21, wherein the first seal layer and the second seal layer both comprise a plurality of deflectable tongues separated by notches and pushing the catalyst carrier into the reactor tube causes the plurality of deflectable tongues of one of the first seal layer and the second seal layer to at least partially seal off the notches of the other of the first seal layer and the second seal layer.

24. The method of claim 21, wherein the seal provides a resistance to insertion of greater than the weight of the catalyst carrier containing catalyst and less than 100 N.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0056] FIG. 1 is a perspective view of a catalyst carrier;

[0057] FIG. 2 is a cross-sectional view of the catalyst carrier of FIG. 1;

[0058] FIG. 3 is an exploded perspective view of the catalyst carrier of FIG. 1;

[0059] FIG. 4 is a plan view of a seal layer for a catalyst carrier;

[0060] FIG. 5 is a schematic side view showing an arrangement of a plurality of seal layers; and

[0061] FIG. 6 is a plan view of first and second seal layers for a catalyst carrier.

DETAILED DESCRIPTION

[0062] In the following, aspects and embodiments of the present disclosure will be described, by way of example only, with reference to example configurations of catalyst carrier. However, it will be understood that according to the present disclosure the catalyst carriers may take various general forms. For example, as well as the examples described herein the catalyst carriers 10 may take other general forms including but not limited to those disclosed in WO2011/048361, WO2012/136971 and WO2016/050520, the contents of which are herein incorporated by reference in their entirety.

[0063] Additionally, in this specification any reference to orientation, for example terms such as top, bottom, upper, lower, above, below and the like have, is used with regard to the orientation of the parts as illustrated in the drawings being referenced but is not to be seen as restrictive on the potential orientation of such parts in actual use. For example, a part described as being orientated vertically may also be orientated horizontally.

[0064] An example of a catalyst carrier 10 according to the present disclosure is shown, by way of example, in FIGS. 1 to 3.

[0065] The catalyst carrier 10 may generally comprise a container that is sized such that it is of a smaller dimension than the internal dimension of a reactor tube into which it is to be placed in use. Typically, a seal will be provided (discussed further below) that is sized such that it interacts with the inner wall of the reactor tube when the catalyst carrier 10 is in position within the reactor tube. Parameters such as carrier length and diameter may be selected to accommodate different reactions and configurations of reactor tube.

[0066] As shown in FIGS. 1 to 3, the catalyst carrier 10 may comprise a container 100 for holding particles of catalyst in use. The container 100 may generally have a bottom surface 101 that closes a lower end of the container 100 and a top surface 102 at an upper end of the container 100. A carrier outer wall 103 may extend from the bottom surface 101 to the top surface 102. A seal 104 may extend from the container 100 by a distance which extends beyond the carrier outer wall 103. The carrier outer wall 103 may have apertures 105 located below the seal 104.

[0067] As shown in FIG. 2, in at least some embodiments the catalyst carrier 10 may more particularly comprise an annular container 110 for holding catalyst in use. The annular container 110 may comprise a perforated inner container wall 111 that defines an inner channel 112 and a perforated outer container wall 113 that may be concentrically arranged about the perforated inner container wall 111. An annular top surface 114 may close an upper end of the annular container 110 and an annular bottom surface 115 may close a lower end of the annular container 110. A lower end of the inner channel 112 may be closed off by a channel end surface 116 except for one or more drain apertures (not shown) that may be provided in the lower end of the inner channel 112. The channel end surface 116 may be formed integrally or separately to the inner container wall 111.

[0068] As shown in the exploded view of FIG. 3, the catalyst carrier 10 may be formed from a number of individual components that may be assembled together by any suitable means, including for example welding. 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 top ring 124, a top cap 125 and one or more annular seal layers 126, 127.

[0069] The catalyst carrier 10 may be formed of any suitable material. Such material will generally be selected to withstand the operating conditions of the reactor. Generally, the catalyst carrier will be fabricated from carbon steel, aluminium, stainless steel, other alloys or any material able to withstand the reaction conditions.

[0070] Suitable thicknesses for the components (other than the annular seal layers 126, 127) will be of the order of about 0.1 mm to about 1.0 mm, preferably of the order of about 0.3 mm to about 1.0 mm.

[0071] The perforated inner tube 120 may comprise the perforated inner container wall 111. The perforated intermediate tube 121 may comprise the perforated outer container wall 113. The outer tube 122 may comprise the carrier outer wall 103 and define the apertures 105. The bottom cap 123 may comprise the bottom surface 101 and or the annular bottom surface 115. The bottom cap 123 may also extend across the perforated inner tube 120 to comprise the channel end surface 116. The annular top ring 124 and the top cap 125 may comprise the annular top surface 114 and may comprise at least part of the top surface 102.

[0072] The size of the perforations in the perforated inner tube 120 and the perforated intermediate tube 121 will be selected such as to allow uniform flow of reactant(s) and product(s) through the catalyst while maintaining the catalyst within the annular container 110. It will therefore be understood that their size will depend on the size of the catalyst particles being used. In an alternative arrangement the perforations may be sized such that they are larger but have a filter mesh covering the perforations to ensure catalyst is maintained within the annular container 110.

[0073] It will be understood that the perforations may be of any suitable configuration. Indeed, where a wall or tube is described as perforated all that is required is that there is means to allow the reactants and products to pass through the walls or tubes.

[0074] The seal 104 may comprise at least a first seal layer 126 and a second seal layer 127. The seal 104 may comprise more than two seal layers 126, 127. For example, it may comprise four, five or six seal layers.

[0075] FIG. 4 illustrates an example of one seal layer 126. FIG. 5 illustrates how a plurality of seal layers 126a to 126f may be provided to form the seal 104. FIG. 6 illustrates another example of seal 104 formed from two seal layers 126, 127.

[0076] The seal layers 126, 127 may comprise portions of an integral sealing element, for example a helical element. Alternatively, and as illustrated in FIGS. 4 to 6, each seal layer 126, 127 may comprise a separate sealing element.

[0077] The first seal layer 126 and the second seal layer 127 overlie each other. Preferably, the layers 126, 127 are in face-to-face contact.

[0078] Each seal layer 126, 127 may comprise a separate seal ring.

[0079] Each seal layer 126, 127 may be flexible.

[0080] Each seal layer 126, 127 may comprise an annular element. An outer edge of each annular element may generally be configured to match the shape of the inner surface of the reactor tube.

[0081] The annular element may be circular. In some examples the outer diameter may be from 80 to 90 mm, optionally about 85 mm. The annular element may have a central aperture 162 for receiving the container of the catalyst carrier 10. The central aperture 162 may have a diameter from 55 to 65 mm, optionally about 60 mm.

[0082] The outer diameter may be chosen to achieve a desired insertion force of the catalyst carrier 10 taking into account the inner diameter of the reactor tube in which the catalyst carrier 10 is to be installed. Preferably an insertion resistance of more than the weight of the catalyst carrier containing catalyst and less than 100 N is desired.

[0083] Each seal layer 126, 127 comprises a plurality of deflectable tongues 160 separated by notches 161. Thus, each of the first seal layer 126 and the second seal layer 127 (and any additional seal layers) may comprise a notched outer edge 163.

[0084] Each seal layer 126, 127 may comprise from 5 to 80 deflectable tongues 160, optionally from 8 to 60 deflectable tongues 160, optionally about 40 deflectable tongues 160.

[0085] Each pair of deflectable tongues 160 may be separated by one notch 161.

[0086] Each seal layer 126, 127 may be formed from a single piece of sheet material. The notched outer edge 163 may be formed by a suitable means such as cutting, stamping, etc.

[0087] The material of each seal layer 126, 127 may be the same or may be different. Each seal layer 126, 127 may be formed from carbon steel, aluminium, stainless steel, other alloys or any material able to withstand the reaction conditions.

[0088] The thickness of each seal layer 126, 127 may be the same or may be different. Different thicknesses may be used to configure different seal layers with different characteristics, including, for example, flexibility, stiffness, compressibility, etc. Each seal layer 126, 127 may have a thickness that is selected to achieve the required insertion force and flexibility of the deflectable tongues 160. In some examples the thickness of each seal layer 126, 127 may be from 15 micron to 500 microns (0.015 mm to 0.5 mm).

[0089] The notches 161 may vary in width from relatively narrow, as in the example of FIGS. 4, to relatively wide, as in the example of FIG. 6.

[0090] The notches 161 may comprise side walls 164 (as most clearly seen in FIG. 6) that are parallel or diverge towards an outer edge of the respective seal layer 126, 127. The notches 161 may be U-shaped or V-shaped.

[0091] The second seal layer 127 is preferably rotationally offset about the longitudinal axis of the catalyst carrier 10 relative to the first seal layer 126 such that the notches 161 of the second seal layer 127 are aligned with the deflectable tongues 160 of the first seal layer 126.

[0092] The first seal layer 126 and the second seal layer 127 may extend perpendicularly from the container 100. Alternatively, the first seal layer 126 and the second seal layer 127 may be angled towards an upper end of the container 100, e.g. towards the top surface 102.

[0093] In some embodiments, the catalyst carrier 10 may comprise three or more seal layers 126, 127 each comprising a plurality of deflectable tongues 160 separated by notches 161. Each seal layer 126, 127 may be rotationally offset about the longitudinal axis of the catalyst carrier 10 relative to at least one of the other seal layers 126, 127 such that the notches 161 of each seal layer 126, 127 may be aligned with the deflectable tongues 160 of at least one of the other seal layers 126, 127. Preferably the notches 161 of each seal layer 126, 127 may be aligned with the deflectable tongues 160 of one or both adjacent seal layers 126, 127. For example, as illustrated in FIG. 5, the notches 161 of seal layer 126c are aligned with the deflectable tongues 160 of both seal layers 126b and 126d.

[0094] An inner edge of the seal layers 126, 127 may be attached together. The attachment may be created before or after the seal layers 126, 127 are attached to the container 100, for example by welding.

[0095] Each seal layer 126, 127 may comprise a key or keyway (not shown) for engaging a complementary keyway or key on the container 100 for maintaining relative rotational alignment of the seal layers 126, 127 with each other.

[0096] An inner portion of each seal layer 126, 127 may define a clamping surface that is sandwiched and retained between the top cap 125 and the annular top ring 124.

[0097] Returning to FIGS. 1 to 3, the bottom surface 101, for example the bottom cap 123, may be shaped to engage with an upper end of another catalyst carrier 10. For example, the bottom surface 101 may comprise an annular recess 130 around the perforated inner tube 120. The top cap 125 may be shaped to engage in the annular recess 130 of another catalyst carrier 10. For example, the top cap 125 may comprise an annular ring 131 that upstands from an annular plug body 132. The annular ring 131 may be shaped and sized to be received in the annular recess 130.

[0098] The bottom surface 101, for example the bottom cap 123 and or channel end surface 116, may include one or more drain holes. Where one or more drain holes are present, they may be covered by a filter mesh.

[0099] The annular top ring 124 may be shaped and sized to engage in an upper end of the outer tube 122. The annular plug body 132 of the top cap 125 may have an outer diameter configured to engage with a central aperture of the annular top ring 124. Engagement of the top cap 125 with the annular top ring 124 may function to sandwich and retain the seal layers 126, 127 of the seal 104 in position.

[0100] The top cap 125 may comprise a central inlet 134 in the annular plug body 132 for enabling entry of liquids and gases into the upper end of the inner channel 112. The annular ring 131 may comprise lateral apertures 133 than enable liquids and gases to reach the central inlet 134.

[0101] The top cap 125 and annular top ring 124 may together comprise a lid of the catalyst carrier 10 that may be used to close off the upper end of the annular container 110. Alternatively, the lid formed from a single component may be used.

[0102] The carrier outer wall 103 may be smooth or it may be shaped. Suitable shapes include pleats, corrugations, and the like.

[0103] The apertures 105 in the carrier outer wall 103 may be of any configuration. In some embodiments, the apertures 105 may be holes or slots.

[0104] The carrier outer wall 103 may continue above the seal 104. Thus the seal 104 may be located at the top of the catalyst carrier 10, optionally as part of the top surface 102, or it may be located at a suitable point on the carrier outer wall 103 provided that it is located above the apertures 105 in the carrier outer wall 103.

[0105] In use, the catalyst carrier 10 may be installed in a reactor tube by any suitable means. The catalyst carrier 10 may be pushed into the reactor tube using a movable ram. During insertion the seal 104 of the catalyst carrier 10 will contact an inner surface of the reactor tube and be deformed. In particular, pushing the catalyst carrier 10 into the reactor tube will cause the first seal layer 126 and the second seal layer 127 of the seal 104 to be deflected into contact with one another as they are engaged by the inner surface of the reactor tube.

[0106] Deformation of the first seal layer 126 and the second seal layer 127 may cause the notches 161 of one or both layers to at least partially close. Preferably, the plurality of deflectable tongues 160 of at least one of the first seal layer 126 and the second seal layer 127 at least partially seal off the notches 161 of the other of the first seal layer 126 and the second seal layer 127.

[0107] The seal 104 may provide a resistance to insertion of greater than the weight of the catalyst carrier containing catalyst and less than 100 N.