A cold and hot wall transition connection structure for industrial furnace manifold

Abstract

The utility model discloses a cold-hot wall transition connection structure for an industrial furnace manifold, and relates to the technical field of industrial furnace manifold connection, including a plurality of conversion tubes, a double-layer manifold, and a double-wall transition structure for connecting each conversion tube with the double-layer manifold, and the double-wall gap of the double-wall transition structure is filled with a castable to avoid overheating. The utility model has a reasonable design, and the double-layer manifold at the bottom of the steam conversion furnace adopts a double-wall structure to form a cold-hot wall transition structure, and the double-wall gap is filled with castables to form a reliable transition structure, avoiding the overheating problem of the traditional structure. The high-temperature medium of the structure is completely isolated from the external environment, and there is no situation in the traditional structure where the external insulation structure falls off due to thermal expansion during the cold-hot wall transition, and the high-temperature structure is directly exposed to the air.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical engineering, and more specifically to the technical field of a cold-hot wall transition connection structure for an industrial furnace manifold. Background Art

[0002] At present, with the strong demand for scale and large-scale equipment in the chemical market, as the core equipment of the synthesis gas preparation device, the design of large-scale industrial furnaces faces unprecedented opportunities and challenges. When industrial furnaces are large-scale, technicians have to face difficulties that they have never encountered before. One of the most basic problems is the heat island effect, especially when there are horizontal and vertical reforming gas collection pipes at the bottom of the steam reformer, this contradiction is more prominent.

[0003] The conversion gas enters the conversion tube, reacts under the combined action of the high temperature conducted outside the tube and the catalyst inside the tube, and reaches the bottom of the conversion furnace. At this time, the conversion gas temperature reaches about 1100°C, and the conversion tube must be connected to the manifold and gas pipeline, and sent to the downstream for processing through the gas pipeline. The outlet of the conversion tube is a hot wall tube structure, which needs to transition to the cold wall structure of the manifold. There are many cases of overheating due to improper design here, which brings great hidden dangers to the safe operation of the industrial furnace. Existing patents disclose the following technologies:

[0004] The patent with the publication number CN2810737Y and the patent name "A self-heating-heat exchange type reformer furnace tube" discloses the following content: It belongs to the technical field of heat exchange type reformer furnace tubes, and mainly involves a self-heating-heat exchange type reformer furnace tube. It is mainly composed of a reformer tube, an outer sleeve, an absorption expansion tube and a catalyst. The lower section of the reformer tube is located in the outer sleeve, which is filled with a catalyst. The lower end is connected to an absorption expansion tube, and the outlet end of the absorption expansion tube extends out of the outer sleeve. A raw gas inlet nozzle is provided on the reformer tube, and a second-stage reformed gas outlet nozzle is provided on the outer sleeve. The utility model has a reasonable design. Since there is no corrugated compensator, the expansion difference between the reformer tube and the outer sleeve is absorbed by the internal absorption expansion tube, and the outer sleeve is directly connected to the second-stage reformed gas inlet manifold, so the structure is simpler and the operation is safer, which can meet the requirements of long-term operation of the heat exchange type reformer. This reformer tube can be used in a self-heating-heat-exchange type ammonia reformer using natural gas as raw material, and can also be used in a self-heating-heat-exchange type methanol device and a hydrogen production reformer in other hydrocarbon pressurized steam reforming devices.

[0005] The above patents indicate that there are literature reports on self-heating-heat exchange type reformer furnace tubes in China, which are mainly composed of reformer tubes, outer sleeves, absorption expansion tubes and catalysts. High-temperature second-stage reformed gas enters the annular gap formed between the reformer tube and the outer sleeve from the open end of the outer sleeve through the second-stage reformed gas inlet manifold, flows in the opposite direction to the raw gas, provides heat for the raw gas reforming reaction, and is discharged from the second-stage reformed gas outlet nozzle after heat exchange. The second-stage reformed gas inlet manifold is annular, and the outer sleeve is provided with an open end. However, the hot and cold wall connection structure of the steam reformer furnace bottom manifold may still cause the furnace bottom to overheat. Utility Model Content

[0006] The purpose of the utility model is to solve the design technical problem of the hot and cold wall connection structure of the bottom manifold of a large steam reformer furnace, and to provide a hot and cold wall transition connection structure for an industrial furnace manifold. In order to prevent the furnace bottom from overheating and ensure the safe and stable operation of the structure, the utility model is suitable for the design of large-scale industrial furnace manifolds.

[0007] In order to achieve the above-mentioned purpose, the utility model specifically adopts the following technical solutions:

[0008] The utility model provides a cold-hot wall transition connection structure for an industrial furnace manifold, comprising a plurality of conversion tubes, a double-layer manifold, and a double-wall transition structure for connecting the conversion tubes with the double-layer manifold. The double-wall gap of the double-wall transition structure is filled with a casting material for preventing overheating.

[0009] Specifically, the double-layer collecting pipe fittings at the bottom of the steam reformer adopt a double-wall structure to form a transition structure between the cold and hot walls, and the gap between the double walls is filled with castables to form a reliable transition structure, thus avoiding the over-temperature problem of the traditional structure.

[0010] The high-temperature medium of this structure is completely isolated from the external environment. There is no situation in the traditional structure where the external insulation structure falls off due to thermal expansion during the transition between cold and hot walls, and the high-temperature structure is directly exposed to the air.

[0011] In one embodiment, the double-wall transition structure includes a double-cone transition section and a double-layer pressure-bearing guide pipe connected below the double-cone transition section. The top of the double-cone transition section is connected to the corresponding conversion tube, and the double-layer pressure-bearing guide pipe is connected to the inside of the double-layer collecting pipe.

[0012] Specifically, this solution sets a double-cone transition section at the bottom of the conversion tube, and cooperates with the heat protection structure of high-temperature insulation products such as cast refractory fibers, so that the cold and hot wall transition structure from the conversion tube outlet to the manifold at the bottom of the large industrial furnace is easy to realize and the structure is reliable. It is particularly suitable for large industrial furnace devices.

[0013] In one embodiment, the double-cone transition section includes an outer cone and an inner cone sleeved inside the outer cone;

[0014] The outer cone is arranged in a right cone shape, with the small end of the outer cone located at the top; the inner cone is arranged in an inverted cone shape, with the large end of the inner cone located at the top; the small end of the outer cone is integrally formed with the large end of the inner cone and is connected to the conversion gas outlet of the conversion tube;

[0015] The large end below the outer cone is connected to the outer tube of the double-layer pressure-bearing guide pipe, and the small end below the inner cone is connected to the inner tube of the double-layer pressure-bearing guide pipe.

[0016] In one embodiment, a double-layer manifold includes a manifold steel shell, and an external castable layer and an internal castable layer sequentially arranged inside the manifold steel shell, the outer wall of the external castable layer is bonded to the inner wall of the manifold steel shell, the inner wall of the external castable layer is bonded to the outer wall of the internal castable layer, the internal castable layer forms a cavity, and the inner layer tube of the double-layer pressure-bearing diversion pipe is connected to the cavity.

[0017] In one embodiment, the double-layer pressure-bearing flow guiding pipe comprises an upper pipe and a lower pipe;

[0018] The upper pipe fitting includes an upper pressure-bearing pipe and an upper guide pipe arranged inside the upper pressure-bearing pipe. The upper end of the upper pressure-bearing pipe is connected to the large end below the outer cone by welding, and the upper end of the upper guide pipe is connected to the small end below the inner cone by welding.

[0019] The lower pipe fittings include a lower pressure-bearing pipe and a lower flow guide pipe arranged inside the lower pressure-bearing pipe. The upper end of the lower pressure-bearing pipe and the lower end of the upper pressure-bearing pipe are assembled and welded together through on-site installation assembly parts, and the lower end of the lower pressure-bearing pipe is connected to the steel shell of the manifold by welding.

[0020] The upper end of the lower guide pipe is communicated with the upper guide pipe, and the lower end of the lower guide pipe is communicated with the cavity through the outer casting material layer and the inner casting material layer in sequence.

[0021] Specifically, the large end of the inner cone is connected to the upper guide pipe and the lower guide pipe to guide the conversion gas through the inner cone and the upper guide pipe and the lower guide pipe to the steel shell of the manifold.

[0022] The outer cone, the upper pressure-bearing pipe and the lower pressure-bearing pipe together form a cavity, and the cavity is poured with refractory castables (lightweight castables). At the construction site, the upper pressure-bearing pipe and the lower pressure-bearing pipe are assembled and welded through on-site installation assembly parts.

[0023] In one embodiment, the space between the upper pressure-bearing pipe and the upper flow-conducting pipe, and the space between the lower pressure-bearing pipe and the lower flow-conducting pipe are filled with lightweight castables.

[0024] In one embodiment, the material of the outer castable layer is a lightweight castable, and the material of the inner castable layer is a heavy castable.

[0025] In one embodiment, the outer wall of each conversion tube is wrapped with a refractory fiber layer, a fiber cover plate allowing the conversion tube to pass through is arranged on the top of the refractory fiber layer, and a furnace bottom insulation system is arranged on the outer side wall of the refractory fiber layer.

[0026] In one embodiment, the upper pressure-bearing pipe is wrapped with a refractory fiber blanket, and the refractory fiber blanket is sheathed with an insulation box.

[0027] Specifically, an insulation box and a refractory fiber blanket are installed at the bottom of the furnace to further isolate possible over-temperature problems between the connections of various parts.

[0028] In one embodiment, a furnace bottom steel plate is provided at the bottom of the refractory fiber layer and the furnace bottom insulation system.

[0029] The beneficial effects of the utility model are as follows:

[0030] 1. The utility model has a reasonable design. The double-layer collecting pipe fittings at the bottom of the steam reformer adopt a double-wall structure to form a cold-hot wall transition structure. The gap between the double walls is filled with castables to form a reliable transition structure, thus avoiding the over-temperature problem of the traditional structure.

[0031] 2. The high-temperature medium of this structure is completely isolated from the external environment. There is no situation in the traditional structure where the external insulation structure falls off due to thermal expansion during the transition between cold and hot walls, and the high-temperature structure is directly exposed to the air.

[0032] 3. The utility model sets a double cone transition section at the bottom of the conversion tube, and cooperates with the heat protection structure of high-temperature insulation products such as castables and refractory fibers, so that the cold and hot wall transition structure from the conversion tube outlet at the bottom of the large industrial furnace to the manifold is easy to achieve and the structure is reliable. It is particularly suitable for large industrial furnace devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the drawings required for use in the implementation mode will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 It is a structural schematic diagram of the utility model;

[0035] Figure 2 yes Figure 1 A cross-sectional view of a conversion tube connected to a corresponding double-wall transition structure;

[0036] Figure 3 yes Figure 2 Schematic diagram of the local structure;

[0037] Figure numerals: 1 - steel shell of collecting pipe, 2 - light castable, 3 - heavy castable, 4 - lower pressure-bearing pipe, 5 - lower guide pipe, 6 - on-site installation assembly, 7 - upper pressure-bearing pipe, 8 - upper guide pipe, 9 - insulation box, 10 - furnace bottom insulation system, 11 - fiber cover, 12 - conversion tube, 13 - refractory fiber layer, 14 - double cone transition section, 15 - furnace bottom steel plate, 16 - refractory fiber blanket. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0041] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0042] Example 1

[0043] like Figures 1 to 3 As shown, this embodiment provides a cold-hot wall transition connection structure for an industrial furnace manifold, including a plurality of conversion tubes 12, a double-layer manifold, and a double-wall transition structure for connecting each conversion tube 12 with the double-layer manifold, and the double-wall gap of the double-wall transition structure is filled with a castable to prevent overheating.

[0044] Specifically, the double-layer collecting pipe fittings at the bottom of the steam reformer adopt a double-wall structure to form a transition structure between the cold and hot walls, and the gap between the double walls is filled with castables to form a reliable transition structure, thus avoiding the over-temperature problem of the traditional structure.

[0045] The high-temperature medium of this structure is completely isolated from the external environment. There is no situation in the traditional structure where the external insulation structure falls off due to thermal expansion during the transition between cold and hot walls, and the high-temperature structure is directly exposed to the air.

[0046] Example 2

[0047] like Figures 1 to 3 As shown, this embodiment provides a cold-hot wall transition connection structure for an industrial furnace manifold, including a plurality of conversion tubes 12, a double-layer manifold, and a double-wall transition structure for connecting each conversion tube 12 with the double-layer manifold, and the double-wall gap of the double-wall transition structure is filled with a castable to prevent overheating.

[0048] The double-wall transition structure includes a double-cone transition section 14 and a double-layer pressure-bearing guide pipe connected below the double-cone transition section 14. The top of the double-cone transition section 14 is connected to the corresponding conversion tube 12, and the double-layer pressure-bearing guide pipe is connected to the inside of the double-layer collecting pipe.

[0049] Specifically, this solution provides a double-cone transition section 14 at the bottom of the conversion tube 12, and cooperates with the heat protection structure of high-temperature insulation products such as cast refractory fibers, so that the cold and hot wall transition structure from the outlet of the conversion tube 12 at the bottom of the large industrial furnace to the manifold is easy to realize and the structure is reliable. It is particularly suitable for large industrial furnace devices.

[0050] Example 3

[0051] like Figures 1 to 3 As shown, this embodiment provides a cold-hot wall transition connection structure for an industrial furnace manifold, including a plurality of conversion tubes 12, a double-layer manifold, and a double-wall transition structure for connecting each conversion tube 12 with the double-layer manifold, and the double-wall gap of the double-wall transition structure is filled with a castable to prevent overheating.

[0052] The double-wall transition structure includes a double-cone transition section 14 and a double-layer pressure-bearing guide pipe connected below the double-cone transition section 14. The top of the double-cone transition section 14 is connected to the corresponding conversion tube 12, and the double-layer pressure-bearing guide pipe is connected to the inside of the double-layer collecting pipe.

[0053] The double-cone transition section 14 includes an outer cone and an inner cone sleeved inside the outer cone.

[0054] The outer cone is arranged in a right cone shape, with the small end of the outer cone located at the top; the inner cone is arranged in an inverted cone shape, with the large end of the inner cone located at the top; the small end of the outer cone is integrally formed with the large end of the inner cone and connected to the reformed gas outlet of the reforming tube 12;

[0055] The large end below the outer cone is connected to the outer tube of the double-layer pressure-bearing guide pipe, and the small end below the inner cone is connected to the inner tube of the double-layer pressure-bearing guide pipe.

[0056] The double-layer manifold fitting includes a manifold steel shell 1, and an external castable layer and an internal castable layer sequentially arranged inside the manifold steel shell 1, the outer wall of the external castable layer is bonded to the inner wall of the manifold steel shell 1, the inner wall of the external castable layer is bonded to the outer wall of the internal castable layer, the internal castable layer forms a cavity, and the inner layer pipe of the double-layer pressure-bearing diversion pipe fitting is connected to the cavity.

[0057] Example 4

[0058] This embodiment is further optimized on the basis of embodiment 3, specifically:

[0059] The double-layer pressure-bearing flow-guiding pipe fittings include an upper pipe fitting and a lower pipe fitting;

[0060] The upper pipe fitting includes an upper pressure-bearing pipe 7 and an upper flow guide pipe 8 arranged inside the upper pressure-bearing pipe 7. The upper end of the upper pressure-bearing pipe 7 is connected to the large end below the outer cone by welding, and the upper end of the upper flow guide pipe 8 is connected to the small end below the inner cone by welding.

[0061] The lower pipe fittings include a lower pressure-bearing pipe 4 and a lower flow guide pipe 5 arranged inside the lower pressure-bearing pipe 4. The upper end of the lower pressure-bearing pipe 4 and the lower end of the upper pressure-bearing pipe 7 are assembled and welded together through a field installation assembly 6. The lower end of the lower pressure-bearing pipe 4 is connected to the manifold steel shell 1 by welding.

[0062] The upper end of the lower flow guide pipe 5 is communicated with the upper flow guide pipe 8, and the lower end of the lower flow guide pipe 5 is communicated with the cavity by sequentially passing through the outer casting material layer and the inner casting material layer.

[0063] Specifically, the large end of the inner cone is connected to the upper guide pipe 8 and the lower guide pipe 5 to guide the conversion gas through the inner cone and the upper guide pipe 8 and the lower guide pipe 5 to the manifold steel shell 1.

[0064] The outer cone, the upper pressure-bearing pipe 7 and the lower pressure-bearing pipe 4 together form a cavity, and the cavity is poured with refractory castables (lightweight castables 2). The upper pressure-bearing pipe 7 and the lower pressure-bearing pipe 4 are assembled and welded through the on-site installation assembly 6 at the construction site.

[0065] Example 5

[0066] This embodiment is further optimized on the basis of embodiment 4, specifically:

[0067] The space between the upper pressure-bearing pipe 7 and the upper flow-conducting pipe 8 and the space between the lower pressure-bearing pipe 4 and the lower flow-conducting pipe 5 are filled with lightweight casting material 2 .

[0068] The material of the outer castable layer is a lightweight castable 2 , and the material of the inner castable layer is a heavy castable 3 .

[0069] The outer wall of each conversion tube 12 is wrapped with a refractory fiber layer 13 , a fiber cover plate 11 is arranged on the top of the refractory fiber layer 13 to allow the conversion tube 12 to pass through, and a furnace bottom insulation system 10 is arranged on the outer side wall of the refractory fiber layer 13 .

[0070] The upper pressure-bearing pipe 7 is wrapped with a refractory fiber blanket 16 , and the refractory fiber blanket 16 is sheathed with an insulation box 9 .

[0071] A furnace bottom steel plate 15 is arranged at the bottom of the refractory fiber layer 13 and the furnace bottom insulation system 10 .

[0072] Specifically, an insulation box 9 and a refractory fiber blanket 16 are arranged at the furnace bottom to further isolate possible over-temperature problems between the connections of various parts.

Claims

1. A cold and hot wall transition connection structure for an industrial furnace manifold, characterized in that: It comprises a plurality of conversion tubes (12), a double-layer collecting tube, and a double-wall transition structure for connecting each of the conversion tubes (12) and the double-layer collecting tube. The double-wall gap of the double-wall transition structure is filled with a casting material that prevents overheating.

2. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 1, characterized in that: The double-wall transition structure comprises a double-cone transition section (14) and a double-layer pressure-bearing guide pipe connected below the double-cone transition section (14); the top of the double-cone transition section (14) is connected to the corresponding conversion tube (12); and the double-layer pressure-bearing guide pipe is connected to the inside of the double-layer collecting pipe.

3. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 2, characterized in that: The double-cone transition section (14) comprises an outer cone cylinder and an inner cone cylinder sleeved inside the outer cone cylinder; The outer cone is arranged in a right cone shape, with the small end of the outer cone located at the top; the inner cone is arranged in an inverted cone shape, with the large end of the inner cone located at the top; the small end of the outer cone is integrally formed with the large end of the inner cone and is connected to the reformed gas outlet of the reforming tube (12); The large end below the outer cone is connected to the outer tube of the double-layer pressure-bearing flow guiding pipe, and the small end below the inner cone is connected to the inner tube of the double-layer pressure-bearing flow guiding pipe.

4. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 3, characterized in that: The double-layer manifold comprises a manifold steel shell (1), and an external castable layer and an internal castable layer sequentially arranged inside the manifold steel shell (1), the outer wall of the external castable layer being in contact with the inner wall of the manifold steel shell (1), the inner wall of the external castable layer being in contact with the outer wall of the internal castable layer, the internal castable layer forming a cavity, and the inner layer pipe of the double-layer pressure-bearing guide pipe being connected to the cavity.

5. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 4, characterized in that: The double-layer pressure-bearing flow-guiding pipe fitting comprises an upper pipe fitting and a lower pipe fitting; The upper pipe member comprises an upper pressure-bearing pipe (7) and an upper flow guide pipe (8) arranged inside the upper pressure-bearing pipe (7), the upper end of the upper pressure-bearing pipe (7) being connected to the large end below the outer cone by welding, and the upper end of the upper flow guide pipe (8) being connected to the small end below the inner cone by welding; The lower pipe fitting comprises a lower pressure-bearing pipe (4) and a lower flow guide pipe (5) arranged inside the lower pressure-bearing pipe (4); the upper end of the lower pressure-bearing pipe (4) and the lower end of the upper pressure-bearing pipe (7) are assembled and welded together through an on-site installation assembly (6); and the lower end of the lower pressure-bearing pipe (4) is connected to the manifold steel shell (1) by welding; The upper end of the lower flow guide pipe (5) is in communication with the upper flow guide pipe (8), and the lower end of the lower flow guide pipe (5) is in communication with the cavity by sequentially passing through the outer casting material layer and the inner casting material layer.

6. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 5, characterized in that: Lightweight casting material (2) is filled between the upper pressure-bearing pipe (7) and the upper flow guide pipe (8), and between the lower pressure-bearing pipe (4) and the lower flow guide pipe (5).

7. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 5, characterized in that: The material of the outer casting material layer is a lightweight casting material (2), and the material of the inner casting material layer is a heavy casting material (3).

8. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 7, characterized in that: The outer wall of each conversion tube (12) is wrapped with a refractory fiber layer (13), the top of the refractory fiber layer (13) is provided with a fiber cover plate (11) allowing the conversion tube (12) to pass through, and the outer side wall of the refractory fiber layer (13) is provided with a furnace bottom insulation system (10).

9. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 7, characterized in that: The upper pressure-bearing pipe (7) is wrapped with a refractory fiber blanket (16) on the outside, and the refractory fiber blanket (16) is sheathed with a heat-insulating box (9) on the outside.

10. The cold and hot wall transition connection structure for industrial furnace manifold according to claim 8, characterized in that: A furnace bottom steel plate (15) is arranged at the bottom of the refractory fiber layer (13) and the furnace bottom insulation system (10).

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