Abstract
The invention relates to a chemical reactor comprising at least one catalyst support system and anti-blocking means arranged around and above a reactor opening, which prevents catalyst or other reactor parts to enter or exit a reactor opening.
Claims
1. A chemical reactor holding a fixed bed catalyst, comprising a catalyst support system arranged in the lower part of the reactor for shielding at least one lower part reactor opening from said catalyst, the catalyst support system comprises flow channels to enable process fluid to flow to or from the reactor through said reactor opening, wherein the catalyst support system further comprises anti-blocking means to prevent blocking of said flow channels.
2. A chemical reactor according to claim 1, wherein said anti-blocking means comprise a geometrical flow labyrinth comprising an outer face of the catalyst support system with a larger total cross sectional flow area than the total cross sectional flow area of the flow channels.
3. A chemical reactor according to claim 2, wherein the cross sectional flow area of the outer face of the catalyst support system is between 1.1 and 4.0 or 1.1 and 2.0 or 1.2 and 1.7 times larger than the total cross sectional flow area of the flow channels.
4. A chemical reactor according to claim 1, wherein the anti-blocking means comprise ramparts.
5. A chemical reactor according to claim 1, wherein the catalyst support system comprises a plurality of bricks comprising said flow channels.
6. A chemical reactor according to claim 5, wherein said bricks are adapted to form a catalyst support system which is in the form of a cone, a dome, an arch, a cylinder, a pyramid, an inverted cone, a half doughnut or has a flat form.
7. A chemical reactor according to claim 6, wherein said bricks are adapted to be arranged in layers to form the catalyst support system.
8. A chemical reactor according to claim 6, wherein said bricks comprise one or more brick legs and brick shoulders, and said flow channels are formed between said brick legs.
9. A chemical reactor according to claim 6, wherein said bricks comprise protruding spacers, and said flow channels are formed between said protruding spacers.
10. A chemical reactor according to claim 6, wherein said bricks are hollow, and said flow channels are foored in the hollow space within the bricks.
11. A chemical reactor according to claim 1, wherein said flow channels have an even cross sectional flow area through the catalyst support system.
12. A chemical reactor according to claim 6, wherein the anti-blocking means are an integrated part of said bricks.
13. A chemical reactor according to claim 1, wherein the anti-blocking means are oblong elements arranged perpendicular to the flow channels.
14. A chemical reactor according to claim 1, wherein the anti-blocking means have a triangular cross-sectional shape and rounded corners.
15. A chemical reactor according to claim 1, wherein the anti-blocking means are independent elements arranged on the outside of said catalyst support system.
16. A chemical reactor according to claim 1, further comprising inert elements or catalyst arranged around said catalyst support system and geometrically shaped to support on said anti-blocking means, while allowing process fluid flow through said flow channels.
17. A chemical reactor according to claim 16, wherein said inert elements are spheres.
18. A chemical reactor according to claim 16 wherein said inert elements are ring shaped.
19. A chemical reactor according to claim 16 wherein said inert elements are random shaped lumps.
20. A chemical reactor according to claim 16 wherein the particles with catalytic activity are arranged around said catalyst support system.
21. A chemical reactor according to claim 17, wherein the inert particle shape is of the same size or larger than the slot width of the anti-blocking means.
22. A chemical reactor according to claim 20, wherein the catalyst particle shape is of the same size or larger than the slot width of the anti-blocking means.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Embodiments of the present invention are explained, by way of example, and with reference to the accompanying drawings. It is to be noted that the appended drawings illustrate only examples of embodiments of this invention and they are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
[0026] FIG. 1 shows a top/side view of a catalyst support system comprising anti-blocking means, ramparts,
[0027] FIG. 2 shows a cross sectional view of a catalyst support system comprising anti-blocking means, ramparts,
[0028] FIGS. 3 and 4 show a cross sectional detail side view of a bricks comprising anti-blocking means,
[0029] FIG. 5 shows a cross sectional detail side view of a bricks comprising anti-blocking means and spheres,
[0030] FIG. 6 shows a cross sectional detail side view of a bricks without anti-blocking means, and spheres,
[0031] FIG. 7 shows a cross sectional detail side view of a bricks comprising protection means, and spheres,
[0032] FIG. 8 shows a detail isometric view of a brick without anti-blocking means,
[0033] FIG. 9 shows a detail isometric view of a brick comprising a rampart, and
[0034] FIGS. 10-16 show detail views of spheres in combination with geometrical shapes.
POSITION NUMBERS
[0035] 01. Catalyst support system [0036] 02. Brick [0037] 03. Brick leg [0038] 04. Brick shoulder [0039] 05. Flow channel [0040] 06. Anti-blocking means [0041] 07. Mono block [0042] 08. Brick layer [0043] 09. Sphere
DETAILED DESCRIPTION
[0044] FIG. 1 shows a catalyst support system 01 to be arranged in the lower part of a chemical reactor (not shown) above and around an opening (not shown) of the reactor. The reactor is partly filled with catalyst (not shown), which is arranged above and possibly also around the catalyst support system. The catalyst support system guards the reactor opening from catalyst entering or exiting the reactor opening. In the embodiment shown, the catalyst support system comprises a plurality of bricks 02 arranged in layers with circular shape. The layers are arranged on top of each other, each circular layer has a smaller diameter than the layer it is arranged on top of, whereby the total catalyst support system obtains a cone-like shape. As shown, the top of the catalyst support system may comprise a flat mono block 07, to close the top of the cone, so no catalyst may enter. Depending on the design demands for the catalyst support system, the cone height may be varied by varying the diameter of the flat mono block. The bricks each comprise brick legs 03 and brick shoulders 04 which form process fluid flow channels 05 between them, and anti-blocking means 06 in the form of ramparts, which can be seen and will be explained in more detail in the following. As best shown on this figure however, is that the flow channels in this embodiment runs radially in the circular brick layers, whereas the distance between each layer of ramparts forms circular gaps for the process flow to flow through, outside the flow channels. In some of the top layers of the catalyst support system, the bricks may not have flow channels, which only slightly affects the total cross sectional flow area of the catalyst support system, since the top layers have relative small diameters compared to the lower layers.
[0045] A cross sectional view of the catalyst support system of FIG. 1 is shown on FIG. 2. Here it is shown how the inner part of the cone shaped catalyst support system is hollow, which allows for the reactor opening to be positioned beneath the cone. As the layers of bricks are circular and the rampart partly interlocks them to prevent an upper layer to slide outwards relative to the layer beneath it, the cone can be assembled layer by layer without the risk of collapsing inwards.
[0046] A cut sectional view (A) of the catalyst support system shown in FIGS. 2 (and 1) is seen in more detail in FIG. 3. The anti-blocking means 06 is in cross sectional shape of a triangle with rounded corners. A strong and crack resistant shape, protecting the brick legs 03 and flow channels against process fluid flow blocking and against mechanical damage from contact with catalyst or other reactor parts (not shown). Also seen is the slight step, the 90 corner between the top of the brick and the rampart. The next brick layered on top of a brick will rest against this step, which prevents it from sliding outwards relative to the brick(s) in the layer below, which is also seen in the detail cross sectional view of FIG. 4.
[0047] In FIG. 5 an embodiment is shown, where the construction of the bricks and ramparts in the catalyst support system is similar to the foregoing figures, but it is shown how catalyst or inert particles in the reactor, in this case in the form of spheres 09 rests upon the outer surface of the catalyst support system. As can be seen, the distance between the ramparts is smaller than the diameter of the spheres, which therefore rest upon the rampart which hence protects the more fragile brick legs from contact with the spheres, contrary to known art as shown in FIG. 6, where the spheres have direct contact with the brick legs. Because of the sturdy construction and geometry of the rampart, there is less risk of breakage and damage by contact with the spheres with the load of the whole catalyst bed above. The reactor may comprise a bed of catalyst as well as inert particles of different shape. For instance, the bed may comprise inert spheres in contact with the catalyst support system in the bottom of the bed and catalyst particles which may have a different geometrical shape and size than the spheres in the upper part of the bed, on top of the spheres. The spheres may also comprise catalytic active material.
[0048] In the embodiments discussed above, the anti-blocking members are integrated with the bricks. A further embodiment as shown in FIG. 7 has anti-blocking means which are not integrated with the bricks, but arranged on the outside of the bricks. This enables the anti-blocking means to be replaced without replacing the inner bricks.
[0049] In the embodiment where the catalyst support system is cone shaped, the bricks may be slightly wedge-shaped as seen in FIG. 8, whereby the shoulders of the bricks are able to contact adjacent brick shoulders on the entire shoulder side area when the circle shaped brick layer is formed. As the layer diameter decreases upwards in the cone shaped catalyst support system, the wedge-angle of each brick will be increased to maintain this tight geometrical fit of the brick shoulders. The brick legs shown in FIG. 8 refers to known art catalyst support system, where it was necessary to have a larger cross sectional area of the flow channels in the bricks outwards facing side, to compensate for the partly blocking of the flow channel by reactor particles such as catalyst or inert particles. But according to this invention, as shown in FIG. 9, it is possible to maintain an even cross sectional area of the flow channels in the bricks, since the outer located ramparts protects the flow channels against damage as well as process fluid flow blockage. This in turn leaves the outer part of the brick legs more sturdy as the dimensions are larger, and thus again minimizes the risk of damage to the bricks.
[0050] The above Figures are only some possible embodiments of the invention. Several other geometrical constructions of anti-blocking means are possible according to the invention, whereas some are shown in FIGS. 10-16. The overall principle is to protect the catalyst support system against both damage and flow blockage, which is possible with anti-blocking means arranged on the outside of the catalyst support system with a sturdy construction and in some embodiments a larger process flow cross sectional area than the cross sectional flow area than the flow channels. In some embodiments, where spheres are chosen to be in contact with the anti-blocking means, the blocked area can be calculated as shown in FIG. 12. As mentioned before bricks and anti-blocking means of several designs can be chosen as best suited for the given task, including but not limited to bricks with one or several flow channels and with internal (bore) or external flow channels, as well as catalyst support systems of different shapes as described.
