Hydrogen production reformer

Abstract

The application provides a hydrogen production reformer, which comprises a combustion chamber and a convection passage, a burner is arranged on the top wall of the combustion chamber and is used for spraying a combustion flame, a fireproof wall is arranged at the connection between the combustion chamber and the convection passage, the fireproof wall is used for plugging the connection between the combustion chamber and the convection passage, a plurality of flow guide holes are arranged on the fireproof wall, and the fireproof wall is formed by refractory bricks. The hydrogen production reformer provides an optimization scheme of adding a fireproof wall in the hearth, aiming at the existing problems in the hearth heat exchange process of the existing natural gas hydrogen production top combustion reformer, and can solve the following technical problems: the residence time of flue gas in the radiation section is prolonged by forced flow guiding, the flue gas short circuit problem is solved; the heat load of each region of the furnace tube is balanced by flow disturbance distribution, the local high temperature area is eliminated, and the uneven heating problem is solved; the heat exchange efficiency is improved by radiation heating cooperation, the flue gas temperature at the outlet of the hearth is reduced, and the fuel gas consumption is reduced.

Description

Technical Field

[0001] This application relates to the technical field of hydrogen production combustion equipment, specifically to a hydrogen production conversion furnace. Background Technology

[0002] The hydrogen production process using natural gas as raw material and employing a top-fired furnace can be widely used in petrochemical, chemical and other fields. The existing combustion furnace structure has the following technical defects. 1. Flue gas short circuit: The high-temperature flue gas in the furnace flows downward in a laminar flow state, which easily forms a short circuit flow. Some flue gas enters the convection section quickly without sufficient contact and heat exchange, and the heat is not effectively absorbed by the furnace tubes, resulting in large exhaust heat loss and low heat exchange efficiency.

[0003] 2. Uneven heating: Uneven heat distribution around the furnace tubes, with some areas having excessively high flue gas velocity (short residence time) and others having excessively low velocity (forming local high temperature zones), can easily cause creep deformation and oxidation damage to the furnace tubes, shortening the service life of the equipment. 3. High fuel consumption: In order to meet the internal temperature required for the conversion reaction, a high furnace outlet flue gas temperature needs to be maintained, resulting in a large fuel gas consumption (accounting for as much as 15%~17% before the modification), and high energy consumption of the unit. 4. Limitations of the retrofit: Existing energy-saving retrofits are mostly focused on waste heat recovery in the convection section and furnace body insulation, without optimizing the flow field inside the furnace from the root, resulting in limited energy-saving effects. Summary of the Invention

[0004] This application provides a hydrogen production converter, which includes a combustion chamber and a convection channel. The top wall of the combustion chamber is equipped with a burner for injecting combustion flames. A fire baffle is provided at the connection between the combustion chamber and the convection channel to block the connection between the combustion chamber and the convection channel. The fire baffle is provided with multiple flow guide holes and is formed by refractory brick masonry.

[0005] In some optional embodiments, the fire barrier is made of high-alumina shaped refractory bricks with an Al2O3 content ≥65%.

[0006] In some optional embodiments, the refractory brick has a refractory temperature ≥1400°C and a room temperature compressive strength ≥50MPa.

[0007] In some alternative embodiments, the fire barrier is sealed around the combustion chamber, and the thickness of the fire barrier is 200-250 mm.

[0008] In some optional embodiments, the opening ratio of the flow guide holes on the firewall is 0.5-2%.

[0009] In some optional embodiments, the guide hole is a rectangular hole with a width of 100-140mm and a height of 60-100mm.

[0010] In some optional embodiments, the horizontal center distance between adjacent guide holes is 300-400 mm, and the vertical center distance is 100-150 mm.

[0011] In some alternative embodiments, the joints between the bricks of the fire barrier are filled with refractory mortar.

[0012] In some optional embodiments, the refractory mortar has an Al2O3 content of ≥65%, a refractoriness of ≥1700°C, and a bond strength of ≥2 MPa.

[0013] In some alternative embodiments, the convection channel has a zigzag bend structure.

[0014] The hydrogen production converter provided in this application addresses the shortcomings of existing natural gas-fired top-fired converters in furnace heat exchange. It proposes an optimized solution by adding a baffle wall within the furnace, which solves the following core technical problems: forced flow guidance extends the residence time of flue gas in the radiant section, resolving the flue gas short-circuiting problem; uniform turbulence distribution balances the heat load in different areas of the furnace tubes, eliminating localized high-temperature zones and resolving uneven heating; synergistic radiant heating improves heat exchange efficiency, reduces furnace outlet flue gas temperature, and decreases fuel gas consumption; and it provides a simple, low-cost, and implementable system modification solution for existing equipment. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the hydrogen production converter of this application; Figure 2 yes Figure 1 A schematic diagram of the structure of the firebreak wall and the combustion chamber in the embodiment. Detailed Implementation

[0017] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the application. Similarly, the following embodiments are only some, not all, embodiments of the present application, and all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present application.

[0018] The terms "first," "second," and "third" used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movement of components in a specific posture (as shown in the figures). If the specific posture changes, the directional indication will also change accordingly. The terms "comprising" and "having," and any variations thereof, in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to these processes, methods, products, or devices.

[0019] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0020] This application provides a hydrogen production conversion furnace. Please refer to [link to relevant documentation]. Figure 1 , Figure 1 This is a schematic diagram of the overall structure of an embodiment of the hydrogen production converter of this application. The hydrogen production converter in this application includes, but is not limited to, the following structures: combustion chamber 100 and convection channel 200.

[0021] Specifically, the top wall of the combustion chamber 100 is provided with a burner 110, which is used to spray combustion flames. A fire baffle 300 is provided at the connection between the combustion chamber 100 and the convection channel 200, which is used to block the connection between the combustion chamber 100 and the convection channel 200.

[0022] Please refer to the following: Figure 2 , Figure 2 yes Figure 1 The embodiment shows a schematic diagram of the structure of the fire baffle 300 and the combustion chamber 100, wherein the fire baffle 300 is provided with multiple flow guide holes 310 and the fire baffle 300 is formed by refractory brick masonry.

[0023] Optionally, the firebreak 300 is made of high-alumina shaped refractory bricks with an Al2O3 content ≥65%. The brick dimensions can be 114mm × 154mm × 174mm (thickness × height × length). The refractory bricks have a fire resistance temperature ≥1400°C and a room temperature compressive strength ≥50MPa.

[0024] The fire baffle 300 is sealed around the combustion chamber and its sides are fitted with the furnace refractory lining with a gap of ≤5mm, filled with refractory mortar. The top of the fire baffle 300 is in close contact with the lower surface of the furnace roof insulation layer in the transition section, forming a sealed barrier and eliminating short-circuit channels for flue gas. The thickness of the fire baffle 300 is 200-250mm. It can be constructed using double-layer refractory bricks, each layer being 114mm thick, with staggered joints.

[0025] Optionally, the guide hole 310 in this embodiment can be a rectangular hole with a width of 100-140mm and a height of 60-100mm. In an optional embodiment, the guide hole diameter is 80mm × 120mm (height × width, rectangular cross-section), and the total guide area is 6 × 80 × 120 = 57600 mm². The opening ratio of the guide hole 310 on the firewall 300 is 0.5-2%. If it is less than this opening ratio range, airflow will be obstructed. If it is greater than this opening ratio range, the turbulence effect will be weakened, and the optimal turbulence effect will not be achieved.

[0026] To achieve optimal turbulence, the horizontal center-to-center distance L between adjacent guide holes 310 is designed to be 300-400 mm, and the vertical center-to-center distance H is designed to be 100-150 mm. The distance D from the bottom of the bottom guide hole 310 to the furnace bottom is approximately 425 mm. The arrangement of the guide holes 310 is not limited to the pattern shown in the diagram; it is acceptable as long as the required spacing and opening ratio are met.

[0027] The hydrogen production converter in this embodiment simultaneously possesses two mechanisms: flow guidance and turbulence (enhanced convective heat transfer) and high-temperature wall radiation (enhanced radiative heat transfer), which work synergistically and cannot be easily derived from existing technologies. The flow guide hole parameters (hole diameter 80mm×120mm, hole spacing 350mm, 6-hole arrangement) are based on the optimal parameters obtained from the measured flow field characteristics of the furnace and construction verification of this device, and are specifically adapted for the custom-designed hydrogen top-fired furnace.

[0028] Optionally, in this embodiment, the brick joints of the fire wall 300 are filled with refractory mortar, which has an Al2O3 content ≥65%, a refractoriness ≥1700°C, and a bonding strength ≥2 MPa.

[0029] Alternatively, please continue reading Figure 1In this embodiment, the convection channel 200 has a zigzag bend structure, which, compared to a traditional straight channel, can slow down the convection velocity, adapt to the blocking effect of the fire baffle, and allow for full heat release with reduced emissions. Additionally, the hydrogen production converter in this embodiment also includes a purification device 400 connected to the end of the convection channel 200 for purifying the flue gas. The detailed structure of the purification device 400 is within the understanding of those skilled in the art and will not be elaborated here.

[0030] The working principle of the hydrogen production converter in this embodiment is as follows.

[0031] The flow guiding and turbulence effect: After the flue gas comes into contact with the fire wall, it is forced to change its flow direction along the guide holes, changing from laminar flow to turbulent flow, destroying the thermal boundary layer and enhancing convective heat transfer; The effect of flow equalization is to distribute the flue gas evenly to all areas of the furnace tube group after turbulence, balance the heat load, and eliminate local high temperature. Delay effect: The residence time of flue gas under the obstruction of the firewall is extended, heat is fully transferred, and heat loss from exhaust is reduced; Secondary radiation effect (core innovation): The fire baffle wall absorbs heat and heats up (about 900~1000°C), emitting infrared radiation to the furnace tube, forming a synergistic enhancement mechanism of convective heat transfer and radiative heat transfer.

[0032] Hydrogen production converters have strict requirements for furnace tube temperature. This invention achieves optimal matching between the heat exchange enhancement location and the conversion reaction depth by precisely installing the fire baffle at the junction of the radiation section and the convection section. This is fundamentally different from the heat exchange optimization of general industrial furnaces.

[0033] The following is a comparative analysis with existing technologies.

[0034]

[0035] The qualitative effect is explained as follows: Energy saving and consumption reduction: The heat utilization rate of the radiation section is significantly improved, which can reduce the flue gas temperature at the furnace outlet and reduce fuel gas consumption while ensuring the depth of the conversion reaction; Safe operation: Eliminate local high temperature zones, avoid creep deformation and oxidation damage to furnace tubes caused by local overheating, and extend equipment service life; Low-cost retrofit: Only a firebreak wall needs to be added to the existing equipment, without replacing core equipment such as furnace tubes and burners, and the construction period is short; Easy to maintain: There are no moving parts; regular inspections are conducted every quarter; localized damage can be repaired during downtime maintenance. High scalability: The parameters of the guide hole can be customized and optimized through CFD flow field simulation, making it compatible with similar top-fired hydrogen conversion furnaces.

[0036] The hydrogen production converter provided in this application addresses the shortcomings of existing natural gas-fired top-fired converters in furnace heat exchange. It proposes an optimized solution by adding a baffle wall within the furnace, which solves the following core technical problems: forced flow guidance extends the residence time of flue gas in the radiant section, resolving the flue gas short-circuiting problem; uniform turbulence distribution balances the heat load in different areas of the furnace tubes, eliminating localized high-temperature zones and resolving uneven heating; synergistic radiant heating improves heat exchange efficiency, reduces furnace outlet flue gas temperature, and decreases fuel gas consumption; and it provides a simple, low-cost, and implementable system modification solution for existing equipment.

[0037] The above description is only a part of the embodiments of this application and does not limit the scope of protection of this application. Any equivalent device or equivalent process transformation made based on the content of this application specification and drawings, or direct or indirect application in other related technical fields, are similarly included in the patent protection scope of this application.

Claims

1. A hydrogen production conversion furnace, characterized in that, The hydrogen production converter includes a combustion chamber and a convection channel. The top wall of the combustion chamber is equipped with a burner for injecting combustion flames. A fire baffle is provided at the connection between the combustion chamber and the convection channel to block the connection between the combustion chamber and the convection channel. The fire baffle is provided with multiple flow guide holes and is formed by refractory brick masonry.

2. The hydrogen production converter according to claim 1, characterized in that, The fire barrier is made of high-alumina shaped refractory bricks with an Al2O3 content of ≥65%.

3. The hydrogen production conversion furnace according to claim 2, characterized in that, The refractory brick has a refractory temperature ≥1400°C and a room temperature compressive strength ≥50MPa.

4. The hydrogen production conversion furnace according to claim 2, characterized in that, The fire barrier is sealed around the combustion chamber, and the thickness of the fire barrier is 200-250mm.

5. The hydrogen production conversion furnace according to claim 1, characterized in that, The opening ratio of the guide holes on the fireproof wall is 0.5-2%.

6. The hydrogen production conversion furnace according to claim 5, characterized in that, The guide hole is a rectangular hole with a width of 100-140mm and a height of 60-100mm.

7. The hydrogen production converter according to claim 6, characterized in that, The horizontal center distance between adjacent guide holes is 300-400mm, and the vertical center distance is 100-150mm.

8. The hydrogen production conversion furnace according to claim 1, characterized in that, The joints between the bricks of the firebreak wall are filled with refractory mortar.

9. The hydrogen production conversion furnace according to claim 8, characterized in that, The refractory mortar has an Al2O3 content of ≥65%, a refractoriness of ≥1700°C, and a bonding strength of ≥2 MPa.

10. The hydrogen production conversion furnace according to claim 1, characterized in that, The convection channel has a zigzag bend structure.

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