Abstract
A heat storage device such as a hot blast stove including a heat regeneration checkerwork made of checker bricks, the checkerwork being supported by a support assembly (16). In accordance with an aspect of the present disclosure, the support assembly having a carrier structure made of refractory material and carrier floor also made of refractory material, the carrier floor resting on the carrier structure and being arranged and formed to carry the checker bricks of the checkerwork.
Claims
1. A heat storage device, in particular a hot blast stove, comprising: a support assembly; and a heat regeneration checkerwork made of checker bricks, said heat regeneration checkerwork being supported by said support assembly, wherein said support assembly comprises: a carrier structure made of refractory material; comprising a plurality of support columns, wherein said support columns are hollow columns and present at least one through-opening along a radial direction of said support columns for gas to flow through; and a carrier floor made of refractory material, said carrier floor resting on said carrier structure and being arranged and formed to carry the checker bricks of the checkerwork; wherein said support assembly does not comprise any metal support or metal carrier elements.
2. The heat storage device according to claim 1, wherein said refractory material is ceramic refractory material.
3. The heat storage device according to claim 1, wherein the carrier floor is arranged and formed to extend an upper surface area of the carrier structure to cover the whole surface area of the checkerwork.
4. The heat storage device according to claim 1, wherein said at least one through-opening of the support columns is a circular through-opening or an oblong through-opening.
5. The heat storage device according to claim 1, wherein the carrier structure further comprises a plurality of support arches.
6. The heat storage device according to claim 1, wherein the carrier structure further comprises a plurality of support walls and a plurality of transition bricks, each brick extending between at least two support walls.
7. The heat storage device according to claim 1, wherein the carrier floor comprises a plurality of rows of checker bricks, wherein successive rows of checker bricks are arranged in a staggered configuration, thereby gradually extending the upper surface area of the support columns to cover the whole surface area of the checkerwork.
8. The heat storage device according to claim 1, wherein the carrier floor comprises a widening block having two parallel surfaces and at least three other surfaces called lateral surfaces, and wherein a first parallel surface of said widening block defines a lower surface configured for resting on the carrier structure and a second parallel surface of said widening block defines an upper surface configured for supporting the checkerwork.
9. The heat storage device according to claim 8, wherein the widening block has the form of a hexagonal prism.
10. The heat storage device according to claim 8, wherein the widening block has the form of a truncated hexagonal pyramid and wherein the lower surface is the smaller of the two parallel surfaces.
11. The heat storage device according to claim 8, wherein the widening block comprises inner channels arranged in a repeating pattern, and wherein an outlet of said inner channels is positioned on the upper surface of the widening block.
12. The heat storage device according to claim 11, wherein the inner channels of the widening block have the same diameter than the channels of the checker bricks and whose outlet are positioned on the upper surface of the widening block to be in alignment with said channels of the checker bricks.
13. The heat storage device according to claim 8, wherein the widening block further comprises a central channel having on the lower surface a cross section corresponding to the inner cross section of the support columns.
14. The heat storage device according to claim 13, wherein the cross section of the central channel of the widening block widens in direction of the upper surface.
15. The heat storage device according to claim 8, wherein each of the at least three lateral surfaces of the widening block comprises at least one groove.
16. The heat storage device according to claim 15, wherein the at least one groove is a circular groove and presents a curvature radius equal to a curvature radius of the inner channels.
17. The heat storage device according to claim 15, wherein the at least one groove is a circular groove and presents a curvature radius equal to a curvature radius of the central channel.
18. The heat storage device according to claim 8, wherein the widening block is formed by a plurality of block sections.
19. The heat storage device according to claim 8, wherein the widening block is dimensioned such that a single row of widening blocks extends the upper surface area of the support columns to cover the whole surface area of the checkerwork.
20. The heat storage device according to claim 19, wherein the carrier floor comprises a plurality of rows of widening blocks staggered in quincunx.
21. The heat storage device according to claim 8, wherein the widening block is dimensioned such that a single row of widening blocks extends the upper surface area of the support columns to partially cover the surface area of the checkerwork, and wherein the carrier floor further comprises one or more rows of checker bricks to cover the whole surface area of the checkerwork.
22. The heat storage device according to claim 1, wherein the carrier floor comprises a plurality of distribution blocks having at least three lateral surfaces.
23. The heat storage device according to claim 22, wherein the distribution blocks comprise at least one inner channel embedded therewithin, and wherein the at least three lateral surfaces comprises at least one circular groove, the at least one groove presenting a curvature radius equals to a curvature radius of said at least one inner channel.
24. The heat storage device according to claim 22 or 23, wherein the distribution blocks forming the carrier floor have the form of a hexagonal prism, having two parallel surfaces and six lateral surfaces perpendicular to said parallel surfaces.
25. The heat storage device according to claim 24, wherein at least one of the distribution blocks further comprises at least one distribution chamber, said chamber forming an opening on one of the two parallel surfaces of the distribution block, the at least one distribution chamber being a half-sphere.
26. The heat storage device according to claim 25, wherein the opening formed by the at least one distribution chamber on one of the two parallel surfaces of the distribution block and the inner diameter of the support columns presents the same size, and are aligned.
27. The heat storage device according to claim 22, wherein the distribution blocks forming the distribution floor are arches.
28. The heat storage device according to claim 22, wherein the distribution blocks are placed upon a widening block or the support layer with the parallel wall arrangement.
29. The heat storage device according to claim 1, wherein the carrier floor comprises at least three rows of checker bricks, said checker bricks being arranged to form distribution chambers above the carrier structure, said distribution chambers being localized between the second and the penultimate rows of checker bricks of said carrier floor.
30. Method for heating blast air using a heat storage device according to claim 1 as a regenerative heat exchanger.
31. Method for heating syngas using a heat storage device according to claim 1 as a regenerative heat exchanger.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0059] Further details and advantages of the present disclosure will be apparent from the following detailed description of not limiting embodiments with reference to the attached drawing, wherein:
[0060] FIG. 1 is a schematic view of a blast stove for carrying out an embodiment of the inventive support assembly;
[0061] FIG. 2 is a schematic view of a first preferred embodiment of the inventive support assembly;
[0062] FIG. 3 is a schematic view of a distribution chamber of the support assembly according to the first preferred embodiment;
[0063] FIG. 4A is a schematic view of a first version of a checker bricks arrangement on top of support columns according to the first preferred embodiment of the inventive support assembly;
[0064] FIG. 4B is a schematic view of a second version of a checker bricks arrangement on top of support columns according to the first preferred embodiment of the inventive support assembly;
[0065] FIG. 5 is a schematic view of a second preferred embodiment of the inventive support assembly;
[0066] FIG. 6 is a schematic sectional view of a first embodiment of a widening block according to the disclosure;
[0067] FIG. 7 is a schematic sectional view of a second embodiment of a widening block according to the disclosure;
[0068] FIG. 8 is a schematic view of a third preferred embodiment of the inventive support assembly;
[0069] FIG. 9 is a schematic view of a fourth preferred embodiment of the inventive support assembly;
[0070] FIG. 10 is a schematic view of a fifth preferred embodiment of the inventive support assembly;
[0071] FIG. 11 is a schematic view of a sixth preferred embodiment of the inventive support assembly;
[0072] FIG. 12 is an enlargement of the sixth preferred embodiment of the inventive support assembly of FIG. 11;
[0073] FIG. 13 is a schematic view of a seventh preferred embodiment of the inventive support assembly;
[0074] FIG. 14 is a schematic view of the seventh embodiment of FIG. 13 along a x-y plan;
[0075] FIG. 15 is a schematic view of the seventh embodiment of FIG. 13 along a x-z plan; and
[0076] FIG. 16 is a schematic view of the seventh embodiment of FIG. 13 along a y-z plan.
DETAILED DESCRIPTION
[0077] A hot blast stove 10, as represented in FIG. 1, comprises a heat exchanging part consisting of an assembly of refractory checker bricks 12 called a checkerwork 14 and a support assembly 16 on top of which the checkerwork 14 rests.
[0078] FIG. 2 shows a detailed view of the support assembly 16 according to a first embodiment of the disclosure. The support assembly 16 is entirely made of refractory material and consists of a carrier structure 20 and carrier floor resting on the carrier structure 20. According to the present embodiment presented FIG. 2-FIG. 4, the carrier floor is a widening structure 30. The carrier structure 20 comprises a plurality of support columns 20a. The widening structure 30 is arranged and formed to gradually extend an upper surface area 26 of the support structure 20 to cover the whole surface area of the checkerwork 14.
[0079] The support columns 20a have the shape of hollow cylinders, forming an inner channel 24 therein. In two particularly preferred embodiments, the diameter of the inner channel 24 of the columns corresponds to either 44% or 50% of the outer diameter of the hollow cylinder. The support columns 20a further present a through-opening 22 along their radial direction, for gas to flow through. It enables gas flow to circulate inside the inner channel 24 of the columns and be distributed inside the channels 32 of the checker bricks 12 forming the checkerwork 14 placed above the upper surface of the support columns 20a.
[0080] In one first preferred embodiment, as seen in FIG. 2-3, twenty-two support columns 20a having an inner diameter of 220 mm and an outer diameter of 500 mm are evenly arranged on the ground of the hot blast stove 10. Each support column further presents a circular through-opening 22 positioned so as not to weaken the support assembly. In the illustrated example, the widening structure (i.e. carrier floor) consists of eight rows of conventional checker bricks 34.1-34.8, i.e. the checker bricks forming the widening structure are of the same type as the checker bricks forming the checkerwork. In other words, only one kind of bricks is used in such a preferred embodiment. The number of checker bricks per row 34.i and percentage of checkerwork surface coverage are presented in Table 1, but any skilled person would know how to adapt these values to any hot blast stove.
TABLE-US-00001 TABLE 1 Row Number of checker bricks Checkerwork surface coverage 1 132 15% 2 264 31% 3 396 46% 4 516 61% 5 624 73% 6 743 87% 7 821 96% 8 851 100%
[0081] The checker bricks 12 forming the first row are evenly distributed on top of each support column, so that six checker bricks 12 rest on top of each support column. As illustrated in FIG. 4A, these six checker bricks 12 are arranged to form a hollow hexagonal prism, each brick contacting neighboring bricks by two non-adjacent sides. Checker bricks 12 forming the upper rows are arranged following the same pattern, thereby gradually extending the upper surface area 26 of the carrier structure to cover the whole surface area of the checkerwork 14. Furthermore, checker bricks 12 are arranged so that gas distribution chambers 40 are formed above the support columns 20a, extending between the 3.sup.rd row 34.3 and the 7.sup.th row 34.7. The purpose of such a chamber is to redistribute the gas into the channels covered by the column and in particular in the channels that were completely obstructed, such as e.g. channels 32.
[0082] Alternatively, in another version of the first preferred embodiment, thirty-one support columns 20a having an inner diameter of 200 mm and an outer diameter of 400 mm are evenly arranged on the ground of the hot blast stove 10. Each support column further presents a through-opening 22 positioned so as not to weaken the support assembly and the widening structure 30 consists of rows of conventional checker bricks 34.i. The first row 34.1 is formed by 186 checker bricks arranged so that six bricks rest on top of each support columns. As illustrated in FIG. 4B, these six checker bricks 12 are arranged to form a roughly triangular shape. Checker bricks of the second row 34.2 are arranged on top of the first row 34.1 in order to expand the surface coverage of the first row of checker bricks 34.1 while maintaining a roughly triangular shape of the checker bricks arrangement above the support column. Checker bricks 12 forming the upper rows are arranged following the same pattern until the surface coverage of the uppermost row corresponds to 100% of the checkerwork surface area. Furthermore, checker bricks 12 are arranged so that gas distribution chambers 40 are formed above the support columns 20a, extending between the 4th row 34.4 and the 5th row 34.5, with a maximal width corresponding to the outer diameter of the support columns.
[0083] FIG. 5 shows a detailed view of the support assembly 16 according to a second embodiment of the disclosure. In this embodiment, thirty-five support columns 20a having an inner diameter of 250 mm and an outer diameter of 500 mm are evenly arranged on the ground of the hot blast stove 10. Each support column further presents a through-opening 22 positioned so as not to weaken the support assembly and the widening structure 30 consists of widening blocks 50.
[0084] A widening block 50, as seen in FIG. 6 or FIG. 7, may have the form of a truncated hexagonal pyramid with two parallel surfaces 56-58 and inner channels 52 arranged in a regular pattern. The inner channels may be straight (FIG. 6) or curved (FIG. 7) with regard to the upper of the two parallel surfaces. The widening block rests on top of a support column 20a by its smaller and lower parallel surface 56, while the upper and larger parallel surface 58 is configured for supporting the checkerwork 14. Widening blocks 50 are dimensioned such that a single row of widening blocks extends the upper surface area 26 of the carrier structure to cover the whole surface area of the checkerwork 14. In order to ensure a smoother flow of gas inside the whole structure of the hot blast stove 10, the inner channels 52 of the widening block 50 preferably have the same diameter than the channels 32 of the conventional checker bricks 12 forming the checkerwork 14 and their outlets are positioned on the upper surface 58 to be in alignment therewith. The widening block 50 further comprises a central channel 54 having on the lower surface 56 a cross section corresponding to the diameter of the support columns inner channel 22, and a larger cross section on the upper surface 58.
[0085] Other possible embodiments of widening blocks 50 may be used by those skilled in the art. In particular, widening blocks 50 may present only one inner channel, preferably described as central channel 54, as represented on FIG. 8. The central channel presents the same diameter than the inner channel 24 of the support columns to ensure a smooth gas flow for gas penetrating inside said support columns 20 through a slot opening 22 on their side. The lateral surfaces of the truncated hexagonal pyramid present a circular groove, with a curvature radius (or diameter) equals to the curvature radius (or diameter) of the central channel. When widening blocks 50 are dimensioned so that a single row of widening blocks is sufficient to cover the whole surface of the above checkerwork 14 (such as represented in embodiments of FIG. 8 or FIG. 9), the widening blocks contact each other. The circular groove on one lateral surface of a first widening block thus faces the circular groove on one lateral surface of a second widening block. The two grooves when assembled will delimit a channel, called a contact channel 66 as it is form by the contact of two blocks. The contact channels 66 actively participate in the uniform gas flow distribution inside the channels of checker bricks placed above, the checker bricks being part of the carrier floor or of the checkerwork. The widening blocks 50, arranged in abutment with each other, are building a single floor for which the flatness is easier to adjust than for separated pillars.
[0086] Furthermore, distribution blocks 62 may be arranged on top of the widening blocks 50 to form a distribution floor 60. The distribution floor is to be considered a part of the carrier floor just as the widening structure formed by the widening blocks. Each of the widening structure 30 and the distribution floor 60 should be considered as a layer of the carrier floor.
[0087] The distribution blocks 62 can be hexagonal prism (as in FIG. 8) or arches (as in FIG. 9) made of refractory material. The main purpose of the distribution blocks is to ensure a smoother and more uniform flow of gas inside the whole structure of the hot blast stove 10, so that distribution blocks 62 may be called smoothing distribution blocks 62a. In the particular embodiments of FIG. 8 and FIG. 9, the distribution blocks 62a present inner channels 64. In preferred embodiments, channels 64 of the distribution blocks 62a are curved, thus ensuring a gas distribution to all channels of the checkerwork placed upon. Lateral surfaces of the distribution blocks 62a present a regular arrangement of circular grooves, so that when two distribution blocks are positioned against each other, new and additional distribution channels are formed for gas to flow through. These channels between two distribution blocks can be described as contact channels 66′ as they are formed by two distribution blocks adjacent to each other.
[0088] Alternatively to what is described on FIG. 9, the carrier structure 20 may comprise a plurality of arches 20b instead of hollow columns 20a. The arches could be described as support arches. In this preferred embodiment, the distribution floor 60 is positioned directly above said support arches (see FIG. 10). The distribution blocks 62a are dimensioned so as to spread between two support arches, thus extending the upper surface area 26 of the carrier structure.
[0089] Another preferred embodiment of the support assembly according to the disclosure is presented on FIG. 11. Support columns 20a are hollow columns presenting a through opening 22 for gas to flow through, but they could as well be full columns, i.e. not hollow. Widening blocks 50 are positioned upon the support columns 20a but without contact between said blocks, so that gas can flow between them. In this particular embodiment, the widening blocks 50 are full, i.e. they do not present any channels. It is therefore necessary to ensure a gas distribution through the inner channels 32 of the checker bricks placed above said widening blocks, so that distribution blocks 62b are employed. The main goal being to feed said channels 32, the distribution blocks 62 may be considered as feeding distribution blocks 62b. They are placed upon the widening blocks 50 along the edges of said blocks thus leaving an unoccupied surface above the center of each of the widening blocks 50, and have the form of arches. This particular arrangement of the distribution blocks 62b combined with their shape ensures that gas will flow through the arches to the free region and will then be distributed to the inner channels of the checker bricks arranged above the widening blocks 50. Arranging distribution blocks on top of widening blocks thus allows the use of full columns and less complex widening blocks 50 which are easier to manufacture, and increases the solidity of the support assembly 16.
[0090] The carrier floor in the illustrated example of FIG. 11 comprises, further to a widening structure 30 made of widening blocks 32 and a distribution floor made of distribution blocks 62, four rows 34.i of checker bricks 12 positioned in a staggered arrangement to gradually extend the upper surface of the distribution blocks, and thus the upper surface of the support columns 20a, to cover a surface corresponding to the whole surface of the checkerwork 14. Rows 34.1 to 34.4 of checker bricks 12 are arranged so as to form a distribution chamber 40 (FIG. 12) above support columns 20a to further optimize the gas flow distribution inside the channels of the checker bricks forming the checkerwork 14.
[0091] Yet, another preferred embodiment of the support assembly according to the disclosure is presented on FIG. 13 to FIG. 16. The carrier structure comprises a plurality of support walls 20c disposed adjacent to one another so as to form rows. The rows are parallel to one another and may be connected by means of connecting cylinders 72, e.g. to enhance stability of the carrier structure. Connecting cylinders may be replaced by rectangular connecting bricks (not shown). The carrier structure may comprise several layers of such rows, arranged in a rectangular (as shown in FIG. 13) or hexagonal manner, thereby forming a grid of support walls. The carrier structure further comprises a plurality of transition bricks 70, which may be arranged in multiple layers, e.g. two layers as shown on FIG. 13. Transition bricks 70 of the lowermost layer are disposed so as to span between two or more parallel support walls 20c. The transition bricks 70 may be provided to reinforce the carrier floor supporting the checkerwork 14.
[0092] In the present embodiment of FIG. 13 to FIG. 16, the carrier floor is made of a plurality of bricks 74. The bricks 74 of the carrier floor may present a cross-section narrowing in the direction of the checker bricks and grooves on their outer surface to ensure and/or improve the gas flow distribution in the channels of the checker bricks forming the checkerwork.
[0093] The support walls 20c and/or the transition bricks 70 may be identical or similar to the burner bricks and support structure used in a burner of a metallurgical furnace. Existing bricks and/or walls may be reused to avoid unnecessary production costs or to avoid having to manufacture complex refractory shapes.
[0094] As one can see on FIG. 15, it is also possible to combine support walls 20c with arches 76 to form the carrier structure, which may ensure a better gas distribution and/or create pathways for operators during maintenance. In some embodiments, support arches 20b may be used as arches 76, but it is not mandatory.
[0095] The arches 76 may be made by a plurality of arch sections 78 as shown in FIG. 16, and bricks 80 forming the support walls 20c may be arranged on top of the arches 76 so as to extend the support wall 20c above the arch 76 to support the transition bricks 70 (see FIG. 16).
[0096] It should be noted that the above embodiments are purely for illustrative purposes. The indicated numbers, sizes and shapes may easily be revised by the skilled person to adapt the support structure to the particular design and operating conditions of the stove in question.
