Support assembly for thermal storage device

Abstract

The present invention proposes a heat storage device, such as a hot air stove (10), comprising a heat-regenerating refractory grid (14) formed from checker bricks (12), the refractory grid (14) being supported by a support assembly (16). According to one aspect of the invention, the support assembly (16) comprises a carrier structure (20) formed from a refractory material and a carrier bed, also formed from a refractory material, the carrier bed resting on the carrier structure (20) and positioned to support the checker bricks of the refractory grid (14).

Description

[Technical Field]

[0001] The present invention relates generally to heat storage devices, particularly hot blast stoves used to generate hot blast, and more particularly to an improved support assembly for supporting heat-regenerating grid refractory bricks designed for use in such heat storage devices. [Background technology]

[0002] Blast furnace operation requires large volumes of hot air (also known as hot blast). Cool air is preheated in large heat storage devices called hot blast stoves and injected into the lower part of the blast furnace as hot blast. Each blast furnace is typically equipped with three hot blast stoves, although other configurations are possible.

[0003] Each hot blast stove is a large regenerative heat exchanger, typically cylindrical with a dome at the top, containing a burner section and a regenerative heat exchange section. The heat exchange section is usually made of an assembly of refractory checkered bricks called a refractory shell. The shell is a welded steel cylinder, typically 6 to 10 meters in diameter and 30 to 50 meters high. The shell is designed to withstand the blast pressure during operation and is insulated to minimize heat loss and prevent structural damage to the shell caused by high thermal stresses.

[0004] The operating cycle of such a hot blast stove essentially comprises two stages: "on gas" and "on air".

[0005] In the "on-gas" stove, combustible gases, primarily blast furnace gas and coke oven gas, and combustion air are mixed and burned in the stove's burner section. The hot flue gas is used to heat the refractory grid by directing it from the top down through the refractory grid. The temperature at the top of the refractory grid, or dome temperature, can reach approximately 1400°C. The temperature of the hot flue gas decreases as it descends toward the bottom of the refractory grid. The bottom of the refractory grid rests on a support assembly, which typically includes a cast iron grid mounted on a cast iron beam resting on the top of a vertical cast iron column called a support post. This creates a cavity below the refractory grid. This cavity is typically approximately 2 to 4 meters high in conventional stoves. While conventional support assemblies have demonstrated long life in stoves, they are limited in the temperatures they can withstand. In practice, the maximum temperature of the hot flue gases at the location of such a support assembly is limited by the hot strength of cast iron, typically to about 400°C.

[0006] When this maximum temperature of the hot flue gases is reached at the support assembly, combustion, and therefore the flow of flue gases, ceases. In other words, the amount of heat that can be stored in the grid refractory bricks is limited by the maximum temperature that can be withstood by the support assembly.

[0007] The hot blast stove is then placed in an "on-air" state. Cold air is introduced into the hot blast stove through the cavity below the checker bricks and directed upward through the high-temperature checker bricks. As the cold air passes through the checker bricks, heat is transferred from the checker bricks to the cold air, converting it to hot air. The hot air is then fed into the blast furnace. To maintain a constant hot air temperature before entering the blast furnace, a certain amount of cold air is bypassed around the stove and introduced into the hot air via a mixer valve before entering the blast furnace. A drop in the hot air outlet temperature below a temperature threshold of approximately 1250°C traditionally dictates a change to another stove. The hot blast stove is then placed in an "on-gas" state again. During normal blast furnace operation, three stoves are used so that at least one stove is always "on-air." However, it should be noted that the number of stoves can be more or less than three, depending on the layout of the manufacturing operation and the type and configuration of the hot blast stoves. For example, it is not uncommon to have two or four stoves per blast furnace, or five stoves per two blast furnaces.

[0008] In integrated steel plants, hot blast stoves account for 10-15% of the total energy requirements. It is known that the efficiency of hot blast stove systems can be improved by increasing the maximum temperature of the hot flue gases, which is currently around 400°C.

[0009] Patent Document 1 discloses the use of a support assembly including a support grid and support posts made of a metal, such as a specific cast iron material, containing a ferrite matrix and a dispersion of vermicular or spherical graphite particles. The use of a common metal and this specific cast iron allows for the use of high-temperature flue gases at a maximum temperature of approximately 600°C. However, cast iron can be nitrided by ammonia contained in blast furnace gas used as the combustible gas when the combustible gas temperature exceeds 500°C, thereby shortening the life of the support assembly in the stove. Summary of the Invention [Problem to be solved by the invention]

[0010] The object of the present invention is to provide a heat storage device, such as a hot blast stove, with an improved support assembly for supporting a heat regenerating grate refractory brick that can withstand the higher temperatures and temperature fluctuations of the hot gases, as well as chemical attack from said gases, while ensuring as uniform a gas distribution within the hot blast stove as possible. [Means for solving the problem]

[0011] The present invention proposes a heat storage device, in particular a hot air stove, comprising a support assembly and a heat-regenerating refractory grid brick formed from checker bricks, the refractory grid bricks being supported by the support assembly. According to one aspect of the invention, the support assembly comprises a carrier structure formed from a refractory material and a carrier bed also formed from a refractory material, the carrier bed being placed on the carrier structure and arranged to support the checker bricks of the refractory grid bricks.

[0012] The use of refractory materials alone prevents degradation of the support assembly even at temperatures as high as approximately 900°C and provides the support assembly with higher resistance to nitriding or stress corrosion cracking. Therefore, since the support assembly according to the present invention does not include a metal support or carrier (structural) element, such as a cast iron part, it can withstand higher temperatures than conventional ones, and using the hot blast stove object of the present invention, air can be heated to higher temperatures than using conventional hot blast stoves. The expression "formed from refractory materials" generally refers to a carrier structure and / or a carrier bed, each of which essentially consists of a refractory material, such as a ceramic refractory material. In other words, the carrier structure and / or the carrier bed are preferably formed solely from refractory materials.

[0013] Because the support assembly can withstand higher temperatures, the thermal storage device can be used to heat gases other than air; for example, the thermal storage device can be used to heat syngas. For simplicity, this application has generally described the heating of air. However, it should be noted that other gases may be heated. Thus, the term "air" may be substituted for "gas" herein.

[0014] Preferably, the refractory material used in the support assembly is a ceramic refractory material. Preferably, the refractory material is the same as that used in the lower part of the refractory grid, such as, but not limited to, a high alumina refractory material. The use of a single material type is beneficial because it reduces the risk of failure of the support assembly in the absence of refractory grid failure.

[0015] The carrier bed may suitably be arranged and configured to extend, preferably gradually, the top surface area of ​​the carrier structure to cover the entire surface area of ​​the refractory checkerboard. By (gradually) extending the top surface area of ​​the carrier structure, the surface area available for supporting the refractory checkerboard is (gradually) increased, i.e. the footprint of the support assembly is (gradually) increased.

[0016] It should be noted that the term "extending" should be understood in the broadest possible way: a carrier bed extending the upper surface area of ​​the carrier structure simply means that possible large holes inherent in the formation of the carrier structure are reduced or covered by the carrier bed, and should naturally not be limited to embodiments in which the carrier structure does not cover the bottom section of the hot blast stove.

[0017] According to one embodiment of the present invention, the support structure may comprise a plurality of support columns made of a refractory material. To ensure gas flow through the majority of the channels of the checker bricks forming the refractory grid, the support columns may be hollow and preferably have at least one through-opening along their radial direction for gas flow. In this embodiment, the at least one opening may be either a circular or elliptical opening, and those skilled in the art will know how to adapt the position, size, and aspect ratio of the opening to ensure satisfactory stability of the support columns.

[0018] The inner diameter of the hollow struts preferably corresponds to 25 to 75% of the outer diameter of these struts, more preferably to a ratio of 40 to 60%, and even more preferably the inner diameter is half the outer diameter.

[0019] The supports are distributed evenly over the hot blast stove's surface to ensure as uniform a gas flow distribution as possible. Preferably, the supports are arranged to cover 5-40%, more preferably 15-30%, even more preferably 20-25% of the hot blast stove's surface to ensure a compromise between the need for stability of the support assembly (e.g., by using larger supports) and sufficient gas flow and distribution.

[0020] According to another embodiment of the invention, the support structure may comprise a plurality of support arches made of refractory material. Each arch may be formed by a plurality of arch sections, preferably designed to be assembled such that the joint areas are along the radial cross section of the global arch. The support arches may be arranged radially relative to the central axis of the thermal storage device or parallel to the central axis of the thermal storage device.

[0021] According to another embodiment of the present invention, the support structure can include a plurality of support walls formed from a refractory material, preferably a ceramic refractory material. The walls can be arranged in parallel, transverse, or hexagonal configurations. The support structure can also include a plurality of transition bricks designed to advantageously extend between at least two of the support walls. According to one embodiment, the transition bricks can form the carrier bed. Alternatively, the transition bricks can support the carrier bed. Thus, in either case, the transition bricks support (directly or indirectly) the checker bricks forming the grid refractory bricks while simultaneously improving the gas flow distribution in all channels of the checker bricks.

[0022] Preferably, in such embodiments using support walls, the carrier bed comprises carrier bricks which may be identical to the bricks forming the refractory checkerboard, so that the refractory checkerboard bricks resting on the carrier bed appear to rest directly on the support wall. In other words, in such embodiments, the carrier bed is formed by the refractory checkerboard bricks. Alternatively, the carrier bricks may be similar to the transition bricks of the support structure.

[0023] In embodiments where the support walls are arranged in a parallel or transverse configuration, it may be advantageous to use rectangular or square bricks as transition bricks in the carrier structure and / or to form the carrier floor.

[0024] It should be noted that the above embodiments can be combined so that the carrier structure can comprise either multiple columns and multiple support arches, or multiple support arches and multiple support walls, or multiple support walls and multiple columns, or multiple columns, multiple support arches, and multiple support walls.

[0025] To distribute the heat carrier medium evenly (ie, for uniform gas distribution), an annular channel may surround the support assembly.

[0026] The annular channel is preferably defined externally by a refractory wall that protects (i.e., insulates) the steel cylinder forming the hot blast stove, for example. This refractory wall can support the cylindrical shaft wall of the hot blast stove. Furthermore, the annular channel is preferably defined internally either by the support assembly itself (e.g., by a carrier structure) or by a perforated cylindrical wall that rests on the floor of the hot blast stove. Such a perforated cylindrical wall can also preferably support the shaft brickwork above.

[0027] The annular channel can be provided in an enlarged lower section of the steel cylinder or can be integrated into the steel cylinder, which may require a reduced refractory brick diameter in this section depending on the height of the annular channel. In such an embodiment, above the annular channel, the refractory bricks can extend to cover the entire inner diameter of the hot blast stove.

[0028] It should be noted that the distribution of the gas is not limited to concentric annular channels around the support assembly: it is also possible to carry out the distribution via one or several arches located between two adjacent support walls of a row of support walls.

[0029] According to various embodiments of the present invention, the carrier bed may comprise at least one of the following two layers, or both layers in combination: - Layers described as widening structures that may be equipped with widening blocks - a layer described as a distribution bed, comprising distribution blocks

[0030] Therefore, in the context of the present invention, the expressions "spreading structure" and "distribution bed" should both be understood to refer to the carrier bed.

[0031] According to a first preferred embodiment, the carrier bed acts as a widening structure and comprises a plurality of rows of checker bricks, successive rows of which are arranged in a staggered configuration, so that the upper surface area of ​​the support columns gradually extends to cover the entire surface area of ​​the refractory grid bricks.

[0032] The arrangement of such staggered checker bricks can be inspired by Roman brickwork. In a preferred embodiment, the checker bricks have the shape of hexagonal columns, and the first row of checker bricks is formed so that 1 to 12 checker bricks are placed on each support, preferably six checker bricks on each support. Preferably, each checker brick in the first row is adjacent to at least two other checker bricks in the same row. The checker bricks contact adjacent bricks on at least two consecutive sides to form the most compact assembly possible, preferably a triangular shape. The checker bricks forming the upper row of the widening structure can be arranged so that each row maintains a generally triangular shape above each support, while increasing the surface area of ​​the triangle in each row.

[0033] Alternatively, a checker brick may contact two adjacent bricks on two non-adjacent sides to form a hexagonal assembly. The checker bricks forming the upper rows of the spreading structure may be arranged so that each row maintains a generally hexagonal shape above each support column while increasing the surface area of ​​the hexagon in each row.

[0034] Preferably, the checker bricks arranged in a staggered configuration to form the carrier bed considered as a widening structure are conventional checker bricks, more preferably the checker bricks are the same as those used for the checker bricks. Existing checker bricks can be reused to avoid unnecessary manufacturing costs or the need to manufacture complex refractory shapes.

[0035] Alternatively, some special bricks can be designed to form the carrier bed. According to a second preferred embodiment, the carrier bed comprises at least one widening block having two parallel sides and at least three other sides, generally six other sides. The at least three other sides are called side faces. A first parallel side of the widening block defines a lower side intended / configured to rest on a carrier structure, preferably on a support, and a second parallel side of the widening block defines an upper side intended / configured to support a refractory grid brick. In other words, the first parallel side of the widening block defines a lower side that rests on the carrier structure, and the second parallel side of the widening block defines an upper side that supports a refractory grid brick.

[0036] The expressions "intended to support refractory grid bricks" or "configured to support refractory grid bricks" should be understood broadly, and the refractory grid bricks are not limited to being in direct contact with the widening blocks, but are arranged above the widening blocks.

[0037] The widening block according to the present invention may have the shape of a hexagonal prism or a hexagonal truncated pyramid.

[0038] The widening block having the shape of a hexagonal pillar may be considered as a large block, a large hexagonal checker brick, or simply a large checker brick. Such a shape of the widening block facilitates its manufacture and installation. It may be easier to extend the upper surface area of ​​the pillar downward to the inner wall of the hot air stove.

[0039] In embodiments where the widening block has the form of a hexagonal truncated pyramid, the smaller of the two parallel faces is considered the lower face, and the widening block can be considered to have an elephant foot shape.

[0040] Regardless of its shape, the widening block intervenes between the support column on which it rests and the load of the lattice refractory bricks that are pressed directly or indirectly down onto it, thereby increasing the area of ​​the support surface of the support column and therefore allowing a better distribution of constraints within the carrier bed.

[0041] Preferably, the widening block has at least one inner channel centered relative to the block's upper surface. In embodiments in which the widening block has two or more inner channels, the channels are preferably arranged in a regular, i.e., repeating, pattern, with their outlets located on the block's upper surface. Therefore, the term "regular pattern" generally refers to the regular, stable arrangement of the channels relative to one another. To ensure smoother gas flow within the entire hot blast stove structure, the channels of the widening block preferably have the same diameter as the channels of each checker brick of a conventional checker brick, and their outlets are preferably positioned to align therewith. The inner channel may be straight and perpendicular to the upper parallel surfaces of the widening block. Alternatively, the inner channel may be curved, with an outlet on the block's upper surface and an inlet on one of at least three sides. This second embodiment may be particularly advantageous when the support pillar is full (i.e., not hollow), in order to ensure gas distribution within the channels of the checker bricks that form the grid refractory bricks arranged linearly above the support pillar. Due to the channels that ensure gas distribution within the channels of the checker bricks, the widening blocks can also function as distribution blocks, even though their main function is to gradually extend the upper surface area of ​​the support pillars to cover the entire surface area of ​​the grid refractory bricks.

[0042] Preferably, if the carrier structure comprises a plurality of hollow struts, the cross section of the central channel of the widening block on the lower surface of the block corresponds to the inner cross section of the struts, and the cross section of the central channel can then widen in the direction of the upper surface of the widening block, which allows for a more uniform distribution of the gas flow through the channels of the checker bricks placed above the widening block.

[0043] In some other embodiments, each of the at least three side surfaces of the widening block comprises at least one groove. Preferably, the at least one groove is a circular groove. Preferably, if the widening block comprises at least one inner channel, the at least one groove has a radius of curvature (or diameter) equal to the radius of curvature (or diameter) of the at least one inner channel. According to some embodiments, the central channel may have a larger diameter than the other inner channels of the widening block. In such a case, the at least one groove may have a radius of curvature (or diameter) equal to the radius of curvature (or diameter) of the smaller inner channel. In other words, the dimensions of the grooves formed in the side surfaces of the widening block are equal to or at least similar to the dimensions of the inner channel formed through the widening block. When two widening blocks are placed against each other, the at least one groove of one block preferably faces the at least one groove of the other block so that at least one channel is formed, thereby improving gas flow distribution through the carrier bed. In other words, the grooves are formed and dimensioned such that when two blocks are adjacent to each other, a new additional channel is formed between two adjacent blocks.

[0044] The widening block may be formed from a number of block sections that are preferably designed to be assembled together so that the joining areas are along the radial or longitudinal cross section of the overall widening block.

[0045] The widening blocks are preferably sized so that one row of widening blocks extends the support top surface area to cover the entire surface area of ​​the refractory grid bricks. In some embodiments where the widening blocks have the shape of hexagonal prisms, i.e., the widening blocks are larger checker bricks, the carrier floor can include multiple rows of widening blocks arranged in a quincunx pattern to increase the stability of the structure.

[0046] Alternatively, the widening blocks may be sized such that one row of widening blocks extends the support column upper surface area to partially cover the surface area of ​​the checker bricks. According to this embodiment, the carrier bed further comprises one or more rows of checker bricks to cover the entire surface area of ​​the checker bricks.

[0047] In other embodiments, the carrier bed comprises a plurality of distribution blocks having at least three sides, typically either four or six sides. The distribution blocks forming the distribution bed and the carrier bed are sometimes referred to as the distribution bed. The distribution bed distributes the gas flow among the channels of the checker bricks forming the refractory grid, enhancing the uniformity of the gas flow.

[0048] The distribution blocks can have two different purposes: preferably, they are used simply to feed the inner channels of the checker bricks placed above them; alternatively or additionally, they are used to ensure a smoother gas flow through the inner channels of the checker bricks placed above them.

[0049] The distribution block may be an arch with four sides, or may have the form of a hexagonal prism with two parallel sides and six sides perpendicular to the parallel sides.

[0050] Preferably, the distribution block, whatever its shape, comprises at least one internal channel embedded therein, at least three sides of which comprise at least one circular groove, the at least one groove having a radius of curvature equal to the radius of curvature of the at least one internal channel. When two distribution blocks are placed against each other, the at least one groove of one distribution block preferably faces the at least one groove of the other distribution block so as to form at least one further channel, thereby improving the distribution of gas flow through the carrier bed. Preferably, the distribution blocks are positioned adjacent to each other to form a plurality of further channels and a continuous distribution bed.

[0051] In some embodiments, the distribution block having the form of a hexagonal prism may further comprise at least one distribution chamber, the chamber forming an opening in the lower surface of the distribution block, the at least one distribution chamber preferably having a hemispherical form. The at least one distribution chamber ensures gas flow through most of the channels of the checker bricks constituting the checker bricks arranged (directly or indirectly) above the distribution block. In some embodiments, the support structure is comprised of a hollow support pillar, and the opening formed by the at least one distribution chamber in the lower surface of the distribution block and the inner diameter of the support pillar are of the same size and aligned to promote gas flow.

[0052] Alternatively, at least one distribution block forming the distribution bed (or carrier bed) may have the form of an arch.

[0053] The distribution blocks according to the present invention may be placed directly on the support columns, support walls or support arches, or on the widening blocks. Each of the at least one distribution block may rest on one widening block or may be spread between two widening blocks.

[0054] In other words, the distribution floors can be advantageous for any kind of support structure, be it columns, arches or walls. These floors may be made up of rectangular, polygonal or arch bricks containing circular channels, oval hole channels or spherical cavities.

[0055] According to another preferred embodiment, the carrier bed comprises at least three rows of checker bricks, which are arranged directly on the support columns or on the widening blocks. The checker bricks are arranged to form a distribution chamber above the support columns, the distribution chamber being located between the second and penultimate rows of checker bricks that are part of the carrier bed. Such an arrangement of the checker bricks allows for a more uniform distribution of the gas flow through the channels of the checker bricks that form the refractory grid, especially in the region above the support columns, where the entrance to one or more channels would otherwise be blocked by the support columns themselves.

[0056] According to another aspect, the present invention proposes a method for generating hot air or high-temperature syngas, i.e., heating cold air or low-temperature syngas, using a hot blast stove equipped with the aforementioned support assembly for supporting a heat-regenerating refractory grid brick formed from checker bricks as a regenerative heat exchanger using a two-stage operating cycle alternating between an "on-air" phase and an "on-gas" phase, as further explained in the Background section above. In operation, blast air or syngas can be directed into the hot blast stove, whereby heat is transferred from the refractory grid brick to the blast air or syngas. The advantages and further embodiments outlined for the (high-temperature) blast stove apply equally to this method. [Brief explanation of the drawings]

[0057] Further details and advantages of the invention will become apparent from the following detailed description of non-limiting embodiments in conjunction with the accompanying drawings. [Figure 1] 1 is a schematic diagram of a blower stove for implementing one embodiment of the support assembly of the present invention; [Figure 2] 1 is a schematic diagram of a first preferred embodiment of a support assembly of the present invention; [Figure 3] FIG. 1 is a schematic view of a dispensing chamber of a support assembly according to a first preferred embodiment. [Figure 4A]FIG. 1 is a schematic diagram of a first version of a checker brick arrangement on the top end of a support column according to a first preferred embodiment of the support assembly of the present invention. [Figure 4B] FIG. 10 is a schematic diagram of a second version of the checker brick arrangement on the top end of the column according to the first preferred embodiment of the support assembly of the present invention. [Figure 5] FIG. 2 is a schematic diagram of a second preferred embodiment of the support assembly of the present invention. [Figure 6] 1 is a schematic cross-sectional view of a first embodiment of a widening block according to the present invention. [Figure 7] FIG. 4 is a schematic cross-sectional view of a second embodiment of an expansion block according to the present invention. [Figure 8] FIG. 10 is a schematic diagram of a third preferred embodiment of the support assembly of the present invention. [Figure 9] FIG. 10 is a schematic diagram of a fourth preferred embodiment of the support assembly of the present invention. [Figure 10] FIG. 10 is a schematic diagram of a fifth preferred embodiment of the support assembly of the present invention. [Figure 11] FIG. 10 is a schematic diagram of a sixth preferred embodiment of the support assembly of the present invention. [Figure 12] FIG. 12 is an enlarged view of the sixth preferred embodiment of the support assembly of the present invention of FIG. 11. [Figure 13] FIG. 10 is a schematic diagram of a seventh preferred embodiment of the support assembly of the present invention. [Figure 14] FIG. 14 is a schematic view of the seventh embodiment of FIG. 13 along the xy plane. [Figure 15] FIG. 14 is a schematic view of the seventh embodiment of FIG. 13 along the xz plane. [Figure 16] FIG. 14 is a schematic view of the seventh embodiment of FIG. 13 along the yz plane. DETAILED DESCRIPTION OF THE INVENTION

[0058] The hot blast stove 10 shown in Figure 1 comprises a heat exchange section consisting of an assembly of refractory checker bricks 12, called refractory grid bricks 14, and a support assembly 16 on which the refractory grid bricks 14 rest.

[0059] FIG. 2 shows a detailed view of the support assembly 16 according to a first embodiment of the present invention. The support assembly 16 is formed entirely from a refractory material and comprises a carrier structure 20 and a carrier bed resting on the carrier structure 20. In this embodiment shown in FIGS. 2-4, the carrier bed 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 the upper surface region 26 of the support structure 20 to cover the entire surface area of ​​the refractory grid bricks 14.

[0060] The pillars 20a have a hollow cylindrical shape and form an internal channel 24 therein. In two particularly preferred embodiments, the diameter of the pillar's internal channel 24 corresponds to either 44% or 50% of the outer diameter of the hollow cylinder. The pillars 20a further have through-openings 22 along their radial direction for gas flow, which allow the gas flow to circulate within the pillar's internal channel 24 and distribute it within the channels 32 of the checker bricks 12 forming the refractory grid 14 arranged above the upper surface of the pillars 20a.

[0061] In a first preferred embodiment, as seen in Figures 2-3, 22 support columns 20a, each with an inner diameter of 220 mm and an outer diameter of 500 mm, are evenly spaced on the ground of the hot blast stove 10. Each support column further has a circular through-hole 22 positioned so as not to weaken the support assembly. In the illustrated example, the widening structure (i.e., carrier floor) 30 consists of eight rows 34.1-34.8 of conventional checker bricks, i.e., the checker bricks forming the widening structure are of the same type as the checker bricks forming the refractory grid. In other words, in this preferred embodiment, only one type of brick is used. The number of checker bricks per row 34.i and the percentage of refractory grid surface coverage are shown in Table 1; those skilled in the art will know how to adapt these values ​​to their hot blast stove. [Table 1]

[0062] The checker bricks 12 forming the first row are evenly distributed over each support column, with six checker bricks 12 resting on each support column. As shown in FIG. 4A, these six checker bricks 12 are arranged to form a hollow hexagonal column, with each brick contacting an adjacent brick on two non-adjacent sides. The checker bricks 12 forming the upper row are arranged according to the same pattern, thereby gradually extending the upper surface area 26 of the carrier structure to cover the entire surface area of ​​the refractory bricks 14. The checker bricks 12 are also arranged so that gas distribution chambers 40 are formed above the support columns 20a and extend between the third and seventh rows 34.3 and 34.7. The purpose of such chambers is to redistribute gas to channels covered by the support columns, particularly to completely blocked channels, such as channel 32.

[0063] Alternatively, in another version of the first preferred embodiment, 31 support posts 20a, each with an inner diameter of 200 mm and an outer diameter of 400 mm, are evenly spaced on the ground of the hot blast stove 10. Each support post further has a through-hole 22 positioned so as not to weaken the support assembly, and the widening structure 30 is made up of conventional checker brick rows 34.i. The first row 34.1 is formed by 186 checker bricks arranged with six bricks on each support post. As shown in FIG. 4B, these six checker bricks 12 are arranged to form a generally triangular shape. The checker bricks of the second row 34.2 are placed on top of the first row 34.1 to increase the surface coverage of the first row 34.1 of checker bricks while maintaining the generally triangular shape of the checker brick arrangement above the support posts. The 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 grid refractory brick surface area. Furthermore, the checker bricks 12 are arranged so that a gas distribution chamber 40 is formed above the columns 20a and extends between the fourth row 34.4 and the fifth row 34.5, with the maximum width corresponding to the outer diameter of the columns.

[0064] 5 shows a detailed view of the support assembly 16 according to a second embodiment of the present invention. In this embodiment, 35 support posts 20a, each with an inner diameter of 250 mm and an outer diameter of 500 mm, are evenly spaced on the ground of the hot blast stove 10. Each support post further has a through-opening 22 arranged so as not to weaken the support assembly, and the widening structure 30 consists of widening blocks 50.

[0065] The widening block 50 may have the shape of a hexagonal truncated pyramid with two parallel sides 56-58 and internal channels 52 arranged in a regular pattern, as seen in FIGS. 6 and 7. The internal channels may be straight (FIG. 6) or curved (FIG. 7) with respect to the upper of the two parallel sides. The widening block rests on the support 20a with its smaller, lower parallel side 56, while the larger, upper parallel side 58 is configured to support the checker bricks 14. The widening blocks 50 are sized so that the upper surface area 26 of the carrier structure extends so that a row of widening blocks covers the entire surface area of ​​the checker bricks 14. To ensure a smoother flow of gas within the entire structure of the hot blast stove 10, the internal channels 52 of the widening blocks 50 preferably have the same diameter as the channels 32 of the conventional checker bricks 12 forming the checker bricks 14, and their outlets are positioned so as to be aligned with the upper surface 58. The widening block 50 further comprises a central channel 54 having a cross section at a lower surface 56 that corresponds to the diameter of the inner channel 22 of the strut, and a larger cross section at an upper surface 58 .

[0066] Other conceivable embodiments of the widening block 50 may be used by those skilled in the art. In particular, the widening block 50 may have only one inner channel, preferably described as a central channel 54, as shown in FIG. 8. The central channel has the same diameter as the inner channel 24 of the support column and ensures smooth gas flow for gas passing through the inside of the support column 20 through the slot openings 22 on those sides. The sides of the hexagonal pyramid have circular grooves whose radius of curvature (or diameter) is equal to that of the central channel. When the widening blocks 50 are sized so that a single row of widening blocks is sufficient to cover the entire surface of the above-mentioned refractory bricks 14 (as shown in the embodiment of FIG. 8 or FIG. 9), the widening blocks contact each other. Thus, the circular groove on one side of the first widening block faces the circular groove on one side of the second widening block. When assembled, the two grooves define a channel, called a contact channel 66, formed by the contact of the two blocks. The contact channels 66 actively contribute to uniform gas flow distribution within the channels of the checker bricks located above, which are part of the carrier bed or grid refractory bricks. The widening blocks 50, placed against each other, form a single bed, the flatness of which is easier to adjust than that of separate pillars.

[0067] Additionally, the distribution blocks 62 may be placed on top of the spreading blocks 50 to form a distribution bed 60. The distribution bed, as well as the spreading structure formed by the spreading blocks, should be considered part of the carrier bed. Each of the spreading structure 30 and the distribution bed 60 should be considered a layer of the carrier bed.

[0068] The distribution block 62 may be a hexagonal prism (as in FIG. 8) or an arch (as in FIG. 9) made of a refractory material. The main purpose of the distribution block is to ensure a smoother and more uniform flow of gas within the entire structure of the hot blast stove 10; therefore, the distribution block 62 is sometimes referred to as a smoothing distribution block 62a. In the specific embodiment of FIGS. 8 and 9, the distribution block 62a has inner channels 64. In a preferred embodiment, the channels 64 of the distribution block 62a are curved, thus ensuring gas distribution to all channels of the refractory bricks placed on top. The side of the distribution block 62a has regularly arranged circular grooves, which form new and additional distribution channels for gas flow when two distribution blocks are placed against each other. These channels between two distribution blocks may be considered contact channels 66′, since they are formed by two adjacent distribution blocks.

[0069] As an alternative to that depicted in Figure 9, the carrier structure 20 may comprise a plurality of arches 20b instead of the hollow columns 20a. The arches may be considered as support arches. In this preferred embodiment, the distribution floor 60 is positioned directly above the support arches (see Figure 10). The distribution block 62a is dimensioned to span between two support arches, thus extending the upper surface area 26 of the carrier structure.

[0070] Another preferred embodiment of the support assembly according to the present invention is shown in FIG. 11. The support columns 20a are hollow columns with through-holes 22 for gas flow, but they may also be solid columns, i.e., solid columns. The widening blocks 50 are placed on the support columns 20a without contact between them, allowing gas to flow between them. In this particular embodiment, the widening blocks 50 are solid, i.e., they do not have any channels. Therefore, a distribution block 62b is used to ensure gas distribution through the inner channels 32 of the checker bricks placed above the widening blocks. The distribution block 62, whose main purpose is to supply the channels 32, can be considered a supply-distribution block 62b. The distribution block is placed on the widening blocks 50 along the edges of the blocks, thus leaving an unoccupied surface above the center of each widening block 50 and having the form of an arch. This particular arrangement of the distribution blocks 62b, combined with their shape, causes the gas to flow through the arches into the free area and then be distributed to the inner channels of the checker bricks positioned above the widening blocks 50. Thus, placing the distribution blocks above the widening blocks allows for the use of integral columns and less complex widening blocks 50 that are easier to manufacture, improving the robustness of the support assembly 16.

[0071] 11 further comprises a widening structure 30 formed from widening blocks 32 and a distribution bed formed from distribution blocks 62, with the fourth row 34.i of checker bricks 12 being positioned in a staggered arrangement so that the upper surfaces of the distribution blocks, and therefore the upper surfaces of the struts 20a, gradually extend to cover a surface corresponding to the entire surface of the checker bricks 14. The rows 34.1 to 34.4 of checker bricks 12 are arranged to form distribution chambers 40 (FIG. 12) above the struts 20a in order to further optimize the gas flow distribution within the channels of the checker bricks forming the checker bricks 14.

[0072] Another preferred embodiment of the support assembly according to the present invention is shown in FIGS. 13-16. The carrier structure includes a plurality of support walls 20c arranged adjacent to one another to form rows. The rows may be parallel to one another and connected by connecting cylinders 72, for example, to increase the stability of the carrier structure. The connecting cylinders may be replaced by rectangular connecting bricks (not shown). The carrier structure may include several layers of such rows arranged in a rectangular or hexagonal pattern (as shown in FIG. 13), thereby forming a grid of support walls. The carrier structure further includes a plurality of transition bricks 70, which may be arranged in multiple layers, for example, two layers as shown in FIG. 13. The lowest transition brick 70 is arranged to span two or more parallel support walls 20c. The transition bricks 70 may be provided to reinforce the carrier bed supporting the grid refractory bricks 14.

[0073] In the present embodiment of Figures 13 to 16, the carrier bed is formed from a plurality of bricks 74. The bricks 74 of the carrier bed may have a cross section narrowing towards the checker bricks and grooves on their outer surface to ensure and / or improve gas flow distribution within the channels of the checker bricks forming the refractory grid.

[0074] The support walls 20c and / or transition bricks 70 may be the same as or similar to the burner bricks and support structures used in the burners of the metallurgical furnace. Existing bricks and / or walls may be reused to avoid unnecessary manufacturing costs or the need to manufacture complex refractory shapes.

[0075] 15, support wall 20c can also be combined with arch 76 to form a carrier structure, which can ensure better gas distribution and / or create a path for operators during maintenance. In some embodiments, support arch 20b can be used as arch 76, but this is not required.

[0076] The arch 76 may be made of multiple arch sections 78 as shown in FIG. 16, and bricks 20 forming a support wall 80c may be placed on top of the arch 76 to extend the support wall 20c over the arch 76 supporting the transition bricks 70 (see FIG. 16).

[0077] It should be noted that the above embodiments are for illustrative purposes only: the numbers, sizes and shapes shown can be easily modified by one skilled in the art to adapt the support structure to the particular configuration and operating conditions of the stove in question. [Explanation of symbols]

[0078] 10. Hot air stove 12 Checker Bricks 14 lattice firebricks 16 Support Assembly 20 Carrier Structure 20 a support 20 b Support arch 20c support wall 22 Through opening 24 inner channel 26 Top surface area of ​​carrier structure 30 Widening structure 32 Checkered Brick Channel 34.i Checkered Brick Row 40 distribution chamber 50 Widening Block 52 Inner channel of widening block 54 Central channel of widening block 56 Bottom side 58 Top 60 distribution floor 62 Distribution Block 62a Smoothing distribution block 62b Supply Distribution Block 64 Distribution Block Inner Channel 66 Widening block contact channel 66´ Distribution Block Contact Channel 70 Transition Bricks 72 Connecting cylinder 74 Carrier Floor Bricks 76 Arch 78 Arch Bricks 80 Bricks forming the supporting wall [Prior art documents] [Patent documents]

[0079] [Patent Document 1] US Patent Application Publication No. 2008199820

Claims

1. A heat storage device, particularly a hot air stove, comprising a support assembly and a heat regenerating grid refractory brick formed from checker bricks, the heat regenerating grid refractory brick being supported by the support assembly, the support assembly comprising: a carrier structure made of a fire-resistant material, said carrier structure comprising a plurality of support columns, said support columns being hollow and having at least one through opening along the diameter of said support columns for the passage of gas; a carrier bed made of refractory material and placed on the carrier structure and configured to support the checker bricks of the refractory grid, A heat storage device wherein the support assembly does not include any metal supports or metal carrier elements.

2. 2. The thermal storage device of claim 1, wherein the refractory material is a ceramic refractory material.

3. 3. A thermal storage device according to claim 1 or 2, wherein the carrier bed is arranged and configured to extend the upper surface area of ​​the carrier structure to cover the entire surface area of ​​the grid refractory bricks.

4. The thermal storage device of claim 3 , wherein the at least one through opening in the support pillar is a circular through opening or a horizontally elliptical through opening.

5. 5. The thermal storage device of claim 1, wherein the carrier structure further comprises a plurality of support arches.

6. 6. The thermal storage device of claim 1, wherein the carrier structure further comprises a plurality of support walls and a plurality of transition bricks, each extending between at least two of the support walls.

7. 7. A heat storage device according to any one of claims 1 to 6, wherein the carrier bed comprises a plurality of rows of checker bricks, successive rows of checker bricks being arranged in a staggered configuration, thereby gradually extending the upper surface area of ​​the support pillars to cover the entire surface area of ​​the grid refractory bricks.

8. 7. The thermal storage device of claim 1, wherein the carrier bed comprises an expansion block having two parallel sides and at least three other sides, called side faces, a first parallel side of the expansion block defining a lower side configured to rest on the carrier structure, and a second parallel side of the expansion block defining an upper side configured to support the refractory grid bricks.

9. The heat storage device according to claim 8 , wherein the widening block has a hexagonal prism shape.

10. The heat storage device according to claim 8 , wherein the widening block has a shape of a hexagonal pyramid truncated, and the lower surface is the smaller of the two parallel surfaces.

11. 11. A thermal storage device according to any one of claims 8 to 10, wherein the widening block comprises internal channels arranged in a repeating pattern, the outlets of the internal channels being located on a top surface of the widening block.

12. 12. The thermal storage device of claim 11, wherein the inner channel of the widening block has the same diameter as the channel of the checker brick, and its outlet is positioned on the top surface of the widening block so as to align with the channel of the checker brick.

13. 12. The thermal storage device of claim 8, wherein the widening block further comprises a central channel having a cross section on the lower surface that corresponds to the inner cross section of the strut.

14. The thermal storage device of claim 13 , wherein the cross section of the central channel of the widening block widens in the direction of the top surface.

15. 15. The thermal storage device according to any one of claims 8 to 14, wherein each of the at least three side surfaces of the widening block comprises at least one groove.

16. 16. The thermal storage device of claim 15, wherein the at least one groove is a circular groove and has a radius of curvature equal to the radius of curvature of the inner channel.

17. 16. The thermal storage device of claim 15, wherein the at least one groove is a circular groove having a radius of curvature equal to the radius of curvature of the central channel.

18. 18. A thermal storage device according to any one of claims 8 to 17, wherein the widening block is formed by a plurality of block sections.

19. 19. A thermal storage device according to any one of claims 8 to 18, wherein the widening blocks are dimensioned so that a row of widening blocks extends the top surface area of ​​the support pillars to cover the entire surface area of ​​the grid refractory bricks.

20. 20. The thermal storage device of claim 19, wherein the carrier bed comprises a plurality of rows of widening blocks staggered in a quincunx pattern.

21. 19. The thermal storage device of claim 8, wherein the widening blocks are dimensioned such that a row of widening blocks extends the upper surface area of ​​the support pillars to partially cover the surface area of ​​the checker bricks, and the carrier bed further comprises one or more rows of checker bricks to cover the entire surface area of ​​the checker bricks.

22. 7. The thermal storage device of claim 1, wherein the carrier bed comprises a plurality of distribution blocks having at least three sides.

23. 23. The thermal storage device of claim 22, wherein the distribution block comprises at least one internal channel embedded therein, the at least three sides comprising at least one circular groove, the at least one groove having a radius of curvature equal to the radius of curvature of the at least one internal channel.

24. 24. A thermal storage device according to claim 22 or 23, wherein the distribution blocks forming the carrier beds have the form of hexagonal prisms with two parallel faces and six side faces perpendicular to the parallel faces.

25. 25. The thermal storage device of claim 24, wherein at least one of the distribution blocks further comprises at least one distribution chamber, said chamber forming an opening in one of the two parallel faces of the distribution block, said at least one distribution chamber preferably being in the form of a hemisphere.

26. 26. The thermal storage device of claim 25, wherein the opening is formed by the at least one distribution chamber in one of the two parallel faces of the distribution block and is aligned with the inner diameters of the posts having the same size.

27. ​​A heat storage device as described in claim 22 or 23, wherein the distribution blocks forming the distribution bed are arches.

28. 28. A thermal storage device according to any one of claims 22 to 27, wherein the distribution block rests on a widening block or on the support layer by the parallel wall arrangement.

29. 29. The thermal storage device of any one of claims 1 to 28, wherein the carrier bed comprises at least three rows of checker bricks, the checker bricks being arranged to form a distribution chamber above the carrier structure, the distribution chamber being located between the second and penultimate rows of checker bricks on the carrier bed.

30. 30. A method for heating blown air using a heat storage device according to any one of claims 1 to 29 as a regenerative heat exchanger.

31. 30. A method for heating synthesis gas using a heat storage device according to any one of claims 1 to 29 as a regenerative heat exchanger.

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