An integrated steam reforming hydrogen production device and method suitable for low-calorific-value feed gas

Abstract

This invention discloses an integrated steam reforming hydrogen production device and method suitable for low-calorific-value feed gas, belonging to the field of hydrogen production and energy conversion technology. The device mainly includes a burner and a furnace body. The burner is located at the top of the furnace body and has a built-in first preheating channel for the feed gas. The furnace body adopts an integrated structure, with a reforming reaction section and a steam generation section from top to bottom. A second preheating channel for the feed gas is arranged on the outer side, and the burner is located inside the reforming reaction section. The outlet of the reforming reaction section is connected to the second preheating channel. The first and second preheating channels and the reforming reaction section are connected in series. The burner flue gas flows sequentially through the second preheating channel and the tail steam generation section. The steam generated in the steam generation section is connected to the reforming reaction section. This invention integrates combustion heating, reforming reaction, steam generation, and waste heat recovery into a compact structure, significantly improving the thermal utilization efficiency under low-calorific-value feed gas conditions. It is suitable for small- to medium-scale and distributed low-calorific-value feed gas steam reforming hydrogen production.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production and energy conversion technology, and more specifically to an integrated steam reforming hydrogen production apparatus and method suitable for low-calorific-value feedstock gases. Background Technology

[0002] With the increasingly prominent environmental problems caused by the irrational use of fossil fuels, clean energy has received widespread attention. Among them, hydrogen energy is considered an important energy carrier due to its advantages of low-carbon or even zero-carbon emissions. At present, industrial hydrogen production mainly adopts thermochemical methods such as steam reforming, and the feed gas is mostly high-calorific-value gases such as natural gas.

[0003] However, in practical applications, there are still a large number of low-calorific-value feedstock gas resources, such as industrial by-product gas, coke oven gas, biogas, and other mixed gases with low combustible component content. These feedstock gases are usually characterized by low calorific value, large compositional fluctuations, and high inert gas content, and their heat release per unit volume is limited, making it difficult to provide a stable and sufficient heat source for the reaction in the steam reforming process.

[0004] Existing steam reforming hydrogen production units are mostly designed for high-calorific-value feedstocks such as natural gas, and typically employ a split structure, with the combustion unit, reforming reaction unit, steam generator, and multi-stage heat exchanger each set up independently. These systems rely on burning high-calorific-value fuels to maintain the temperature environment required for the reforming reaction. However, reforming reactions using low-calorific-value feedstocks require even higher temperatures. When applied to low-calorific-value feedstocks, problems such as insufficient furnace temperature, low heat utilization, and difficulty in effectively recovering waste heat from flue gas can easily occur, leading to decreased system efficiency and instability.

[0005] Meanwhile, existing devices are generally large in size, suitable for centralized large-scale hydrogen production scenarios, but not conducive to small- to medium-scale or distributed on-site hydrogen production applications. For low-calorific-value feedstock gases, their resources are scattered and small in scale, making them more suitable for on-site conversion and utilization using compact, integrated devices.

[0006] Therefore, it is necessary to provide a steam reforming hydrogen production unit suitable for low-calorific-value feed gas. By optimizing the combustion heating structure, enhancing the heat exchange method, and shortening the waste heat recovery path, the unit can achieve cascade utilization of heat, improve the thermal utilization efficiency of low-calorific-value gas, and meet the needs of small- and medium-sized and distributed hydrogen production applications. Summary of the Invention

[0007] To address the problems of insufficient heating capacity, low heat utilization rate, large system volume, and difficulty in meeting the needs of distributed applications in the steam reforming hydrogen production process of low-calorific-value feed gas, this invention provides an integrated steam reforming hydrogen production device and method suitable for low-calorific-value feed gas. It integrates functional units such as combustion heating, reforming reaction, steam generation, and waste heat recovery into a compact and highly functional integrated steam reforming hydrogen production structure.

[0008] To achieve the above objectives, in a first aspect, the present invention provides an integrated steam reforming hydrogen production device suitable for low-calorific-value feed gas, comprising a burner and a furnace body; the burner is disposed on the upper part of the furnace body, and a first preheating channel for feed gas is provided in the burner; the furnace body includes a reforming reaction section, a steam generation section, and a second preheating channel for feed gas; the reforming reaction section is disposed above the steam generation section and is constructed as an integrated unit; the burner is disposed inside the reforming reaction section, and the second preheating channel for feed gas is arranged outside the reforming reaction section and the steam generation section; the gas outlet of the reforming reaction section is connected to the high-temperature reformed gas inlet of the second preheating channel for feed gas; a low-temperature feed gas inlet and a medium-temperature feed gas outlet are provided on the first preheating channel for feed gas; a medium-temperature feed gas inlet is provided on the second preheating channel for feed gas and connected to the medium-temperature feed gas outlet of the first preheating channel for feed gas; a high-temperature feed gas outlet is provided on the second preheating channel for feed gas and connected to the feed gas inlet of the reforming reaction section; the flue gas passage of the burner is connected to the second preheating channel for feed gas; the steam generation section is arranged at the tail end of the flue gas passage; the flue gas flows sequentially through the second preheating channel for feed gas and the steam generation section.

[0009] Furthermore, the burner includes a premixed gas inlet, a flow equalization orifice plate, an upper part of an upper annular raw material gas header, a lower part of an upper annular raw material gas header, a lower annular raw material gas header, an inner tube, and an outer tube; the inner tube and the outer tube are coaxially arranged to form a sleeve, and the inner tube and the outer tube are arranged around the flow equalization orifice plate; the upper exposed part of the burner is provided with an upper annular raw material gas header, and the part of the burner that extends into the furnace body is provided with a lower annular raw material gas header; a baffle is provided in the middle of the upper annular raw material gas header, dividing the upper annular raw material gas header into an upper part and a lower part; a low temperature raw material gas inlet is opened on the side of the upper part of the upper annular raw material gas header, and a medium temperature raw material gas outlet is opened on the side of the lower part of the upper annular raw material gas header.

[0010] Furthermore, the inner tube and the gap between the inner and outer tubes constitute the first preheating channel for the raw material gas. The outer tube connects the lower annular raw material gas header and the lower part of the upper annular raw material gas header, and the two ends of the inner tube connect the lower annular raw material gas header and the upper part of the upper annular raw material gas header.

[0011] Furthermore, the second preheating channel for raw material gas includes an annular cavity, multiple raw material gas preheating tube bundles, an annular medium-temperature raw material gas header, and an annular high-temperature raw material gas header. The annular cavity is located outside the reforming reaction section, and the annular medium-temperature raw material gas header is arranged outside the annular reaction raw material header. A high-temperature conversion gas inlet is provided on the annular cavity, and a low-temperature conversion gas outlet is provided on the side of the annular cavity opposite to the high-temperature conversion gas inlet. The high-temperature conversion gas inlet is connected to the gas outlet of the reforming reaction section. The upper end of the raw material gas preheating tube bundle is connected to the annular medium-temperature raw material gas header, and the lower end of the raw material gas preheating tube bundle is connected to the annular high-temperature raw material gas header. The raw material gas outlet of the first preheating channel for raw material gas is connected to the medium-temperature raw material gas inlet. The heat exchange tubes of the raw material gas preheating tube bundle are bare tubes or finned tubes.

[0012] Furthermore, the annular cavity divides the second preheating channel of the raw material gas into upper and lower parts. The heat release medium in the upper part of the second preheating channel of the raw material gas is high-temperature conversion gas, and the heat release medium in the lower part of the second preheating channel of the raw material gas is flue gas.

[0013] Furthermore, the steam generation section includes multiple steam generation heat exchange tube bundles, a water collection tank, a steam header, a steam transition pipe, a flue gas outlet, and radial support plates. The water collection tank is located at the bottom of the furnace body. Multiple steam generation heat exchange tube bundles are arranged circumferentially. The upper end of the steam generation heat exchange tube bundle is connected to the steam header, and the lower end of the steam generation heat exchange tube bundle is connected to the water collection tank. A feedwater inlet is provided on the water collection tank. The steam header is located below the reforming reaction section, and the flue gas outlet is located at the center of the bottom of the furnace body. The steam header is connected to a steam jacket through a steam transition pipe, and a saturated steam outlet is provided on the steam jacket. The steam header is fixed to the inner wall of the annular cavity by multiple radial support plates. The heat exchange tubes of the steam generation heat exchange tube bundle are finned tubes and are arranged in a staggered manner.

[0014] Furthermore, the steam header is equipped with a baffle plate, which is an inverted cone-shaped baffle plate.

[0015] Furthermore, the steam jacket is equipped with a spiral guide plate, and the saturated steam outlet is connected to the inlet of the reforming reaction section.

[0016] Furthermore, the reforming reaction section includes multiple reforming reaction tubes, an annular feedstock header, and an annular conversion gas header. The annular feedstock header is equipped with a feedstock inlet, the annular conversion gas header is located outside the annular feedstock header, and the annular conversion gas header is equipped with a high-temperature conversion gas outlet. The reforming reaction tubes are arranged circumferentially around the burner, and the reforming reaction tubes are serpentine reversing tubes. A catalytic bed is provided inside the reforming reaction tubes. A circumferential flue gas guide is provided at the bottom of the reforming reaction section. The circumferential flue gas guide connects the burner and the second preheating channel for the feedstock gas, and the reforming reaction tubes pass through the flue gas guide.

[0017] Secondly, the present invention provides a highly efficient, compact, integrated steam reforming method for producing hydrogen from low-calorific-value feed gas, based on the aforementioned integrated steam reforming hydrogen production apparatus suitable for low-calorific-value feed gas, comprising: After the premixed gas enters the burner and is ignited, a continuous and stable combustion flame surface is formed on the outer surface of the burner. The heat released during the combustion process is transferred to the reforming reaction section in the form of flame radiation heat, while generating high-temperature flue gas. Low-temperature feed gas enters the first preheating channel, absorbing heat from the burner to cool it down. The low-temperature feed gas absorbs heat to become medium-temperature feed gas. The feed gas and steam enter the reforming reaction section to generate high-temperature reformed gas. The high-temperature reformed gas and high-temperature flue gas enter the second preheating channel to heat the medium-temperature feed gas, which is then heated to become high-temperature feed gas. Feedwater enters the steam generation section, where flue gas heats the feedwater to form steam. The steam and feed gas enter the reforming reaction section together. The flue gas flows out of the burner, passing through the second preheating channel and the steam generation section before being discharged.

[0018] Compared with existing technologies, the integrated steam reforming hydrogen production device and waste heat utilization method provided by this invention have the following significant advantages: This invention provides an integrated steam reforming hydrogen production device suitable for low-calorific-value feed gas, comprising a furnace body and a burner. The furnace body includes a reforming reaction section and a steam generation section, which are arranged vertically and integrated into a single structure. The burner is located in the reforming reaction section and is used to burn fuel gas to generate high-temperature flue gas and heat the steam reforming reaction in the reforming reaction section. The steam generation section is located at the lower part of the furnace body and includes multiple compact steam generation heat exchange tube bundles. The high-temperature flue gas exchanges heat with the reforming reaction section and the steam generation section within the furnace body, realizing heat supply for the reforming reaction and steam generation. The device also includes a feed gas preheating channel for preheating the feed gas. The steam in the steam section serves as the feed gas for the steam reforming reaction. After preheating, the feed gas is introduced into the reforming reaction tubes for steam reforming to produce hydrogen-containing reformed gas. This invention adopts an integrated structural design, combining the reforming reaction section, steam generation section, and waste heat utilization unit, reducing independent heat exchange equipment and the footprint of the device; by setting up a feed gas preheating channel, the low-calorific-value feed gas is fully preheated before entering the reaction tube, improving the temperature stability of the reforming reaction and solving the problem of reaction heating under low-calorific-value gas conditions; by setting a steam jacket on the outer wall of the furnace body, the steam dryness is improved while cooling the furnace body, and the steam is used for the reforming reaction feed, improving the overall utilization level of heat. This invention has a compact structure and a short heat utilization path, which can improve the energy utilization efficiency of low-calorific-value raw gas, with an energy utilization efficiency of up to 103%, and has good prospects for engineering applications.

[0019] Furthermore, the outer wall of the furnace body is provided with a steam jacket for cooling the furnace body and improving the dryness of the steam.

[0020] Furthermore, the burner is a fully premixed and cooled burner, equipped with a feed gas preheating channel. The feed gas is used to cool the burner before entering the reforming reaction tube, reducing NO₂ levels. X It discharges gas while simultaneously preheating the raw material gas.

[0021] Furthermore, the furnace body is provided with a raw material gas preheating channel, and the heat exchange tubes in the raw material gas preheating channel are bare tubes or finned tubes.

[0022] Furthermore, the compact steam generator heat exchange tube bundle is a bare tube or a finned tube, and the heat exchange tube bundle is arranged in a staggered manner to increase the degree of flue gas flow disturbance and reduce the heat transfer stagnation zone.

[0023] Furthermore, the steam jacket is equipped with a guide plate to improve steam flow and increase steam dryness.

[0024] Furthermore, the steam header of the steam generation section is equipped with a baffle plate to prevent steam from accumulating on the top of the steam header, thereby causing heat transfer deterioration and accelerating steam discharge. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of the integrated steam reforming hydrogen production device provided by the present invention.

[0026] Figure 2 This is an internal structural diagram of the integrated steam reforming hydrogen production device provided by the present invention.

[0027] Figure 3 This is a three-dimensional structural diagram of the burner provided by the present invention.

[0028] Figure 4 This is a cross-sectional structural diagram of the burner provided by the present invention.

[0029] Figure 5 This is a schematic diagram of a partial structure of the furnace body provided by the present invention.

[0030] Figure 6 yes Figure 2 Sectional view of AA.

[0031] Figure labeling: 1-burner, 101-premixed fuel gas inlet, 102 flow equalization orifice plate, 103-upper part of upper annular raw material gas header, 104-lower part of upper annular raw material gas header, 105-lower annular raw material gas header, 106-inner pipe, 107-outer pipe, 108-low temperature raw material gas inlet, 109-medium temperature raw material gas outlet; 2-furnace body, 211-reformation reaction tube, 212-reaction raw material inlet, 213-high temperature conversion gas outlet, 214-annular reaction raw material header, 215-annular conversion gas header, 216-circumferential flue gas guide port; 22 1-Tube bundle, 222-Water collection tank, 223-Steam header, 224-Feed water inlet, 225-Steam transition pipe, 226-Baffle plate, 227-Flue gas outlet, 228-Radial support plate; 231-Annular cavity, 232-Raw gas preheating tube bundle, 233-High temperature conversion gas inlet, 234-Low temperature conversion gas outlet, 235-Annular medium temperature raw gas header, 236-Annular high temperature raw gas header, 237-Medium temperature raw gas inlet, 238-High temperature raw gas outlet; 239-Spiral baffle plate, 240-Saturated steam outlet, 241-Steam jacket. Detailed Implementation

[0032] The technical solutions of this invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of this invention. The following description of an exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0033] The terms "first," "second," "primary," "secondary," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein.

[0034] like Figure 1 , Figure 2 As shown, the present invention discloses an integrated steam reforming hydrogen production device suitable for low-calorific-value feed gas, including a burner 1 and a furnace body 2, wherein the burner 1 is disposed inside the furnace body 2.

[0035] For example, such as Figure 3 , Figure 4As shown, the burner 1 includes a premixed gas inlet 101, a flow equalization orifice plate 102, an upper part 103 of an upper annular raw material gas header, a lower part 104 of an upper annular raw material gas header, a lower annular raw material gas header 105, an inner tube 106, an outer tube 107, a low-temperature raw material gas inlet 108, and a medium-temperature raw material gas outlet 109. Specifically, the inner tube 106 and the outer tube 107 are coaxially arranged to form a sleeve, and the inner tube 106 and the outer tube 107 are arranged around the flow equalization orifice plate 102. The inner tube 106 and the gap between the inner tube 106 and the outer tube 107 constitute the first preheating channel for the raw material gas. The premixed gas enters from the burner top inlet 101, passes circumferentially through the flow equalization orifice plate 102, and then passes through the gap of the first preheating channel for the raw material gas before combustion. The upper exposed part of the burner 1 is provided with an upper annular raw material gas header. The portion of the burner 1 that extends into the furnace body 2 is provided with a lower annular raw material gas collector 105. The upper annular raw material gas collector has a partition in the middle, dividing it into an upper part 103 and a lower part 104. An outer pipe 107 connects the lower annular raw material gas collector 105 and the lower part 104, and the two ends of an inner pipe 106 connect the lower annular raw material gas collector 105 and the upper part 103. A low-temperature raw material gas inlet 108 is opened on the side of the upper part 103 of the upper annular raw material gas header, and a medium-temperature raw material gas outlet 109 is opened on the side of the lower part 104 of the upper annular raw material gas header. The first preheating channel for the raw material gas is a single-ring pipe. The low-temperature raw material gas first enters the upper part 104 of the upper annular header from the low-temperature raw material gas inlet 108, then flows downward along the inner pipe 106 of the first preheating channel, flows to the lower annular header 105, then flows upward along the outer pipe 107 of the first preheating channel, reaches the lower part 105 of the upper annular raw material gas header, then flows to the lower part 104 of the upper annular raw material gas header, and finally flows out from the medium-temperature raw material gas outlet 109. The first preheating channel for the raw material gas reduces the burner temperature, thereby reducing the NO emission of the burner 1. X The temperature drops, and at the same time, the heat released by this cooling can be fully utilized to preheat the raw gas from low temperature to medium temperature (i.e., the first stage of preheating of the raw gas).

[0036] For example, Figure 2As shown, the furnace body 2 is equipped with a reforming reaction section, a steam generation section, and a second preheating channel for raw material gas. The reforming reaction section is located at the top of the furnace body 2 and includes multiple reforming reaction pipes 211, a raw material inlet 212, a high-temperature conversion gas outlet 213, an annular raw material header 214, an annular conversion gas header 215, and a circumferential flue gas guide port 216. A reaction feed inlet 212 is provided on the annular reaction feed header 214, and an annular conversion gas header 215 is provided on the outside of the annular reaction feed header 214. A high-temperature conversion gas outlet 213 is provided on the annular conversion gas header 215. A circumferential flue gas guide port 216 is provided at the lower part of the reforming reaction section. The circumferential flue gas guide port 216 connects the burner 1 and the second preheating channel of the feed gas. The reforming reaction tube 211 is arranged around the burner 1 and designed as a serpentine reversing tube. The reforming reaction tube 211 passes through the flue gas guide port 216. A catalytic bed is provided inside the reforming reaction tube 211. The feed flows back and forth in the tube, which can prolong the residence time, increase the heat exchange area, improve the temperature distribution, and make the device structure more compact.

[0037] An annular reforming gas header 215 is located around the annular reaction feedstock header 214. The annular reaction feedstock header 214 has a reaction feedstock inlet 212, and the annular reforming gas header 215 has a high-temperature reforming gas outlet 213. The annular reaction feedstock header 214 and the annular reforming gas header 215 are respectively connected to both ends of the reforming reaction tube 211. Specifically, after the premixed fuel gas enters the burner 1 and is ignited, a continuous and stable combustion flame surface is formed on the outer surface of the burner 1. The heat released during combustion is transferred to the reforming reaction tube 211 in the form of flame radiation heat, while simultaneously generating high-temperature flue gas. The feedstock includes feed gas and steam. The feedstock enters from the reaction feedstock inlet 212, flows into the reforming reaction tube 211 via the annular reaction feedstock header 214, and mainly absorbs radiant heat to rise to the temperature required for the reforming reaction. Under the condition of a catalyst, a steam reforming reaction occurs to generate hydrogen-containing reforming gas, which flows out from the high-temperature reforming gas outlet 213 via the annular reforming gas header 215.

[0038] The second preheating channel for raw material gas includes an annular cavity 231, multiple raw material gas preheating tube bundles 232, a high-temperature conversion gas inlet 233, a low-temperature conversion gas outlet 234, an annular medium-temperature raw material gas header 235, an annular high-temperature raw material gas header 236, a medium-temperature raw material gas inlet 237, and a high-temperature raw material gas outlet 238. The annular cavity 231 is located outside the reforming reaction section. The annular medium-temperature raw material gas collector 235 is arranged outside the annular reaction raw material collector 214. A high-temperature conversion gas inlet 233 is provided on the annular cavity 231. A low-temperature conversion gas outlet 234 is provided on the side of the annular cavity 231 opposite to the high-temperature conversion gas inlet 233. The high-temperature conversion gas inlet 233 is connected to the high-temperature conversion gas outlet 213. The upper end of the raw material gas preheating tube bundle 232 is connected to the annular medium-temperature raw material gas collector 235. The lower end of the raw material gas preheating tube bundle 232 is connected to the annular high-temperature raw material gas collector 236. The medium-temperature raw material gas outlet 109 is connected to the medium-temperature raw material gas inlet 237. The raw material gas preheating tube bundle 232 consists of multiple vertically arranged tube bundles (using finned tubes or bare tubes, preferably finned tubes). Its upper end is connected to the top of the furnace body 2, and its lower end passes through the annular cavity 231 and extends to the bottom of the furnace body 2. Therefore, the annular cavity 231 divides the second preheating channel of the raw material gas into upper and lower parts. The hydrogen-containing converted gas flowing out of the high-temperature converted gas outlet 213 continues to be introduced into the annular cavity 231 through the high-temperature converted gas inlet 233, and the raw material gas flowing out of the medium-temperature raw material gas outlet 109 on the burner 1 continues to be introduced into the raw material gas preheating tube bundle 232 through the medium-temperature raw material gas inlet 237 and the annular medium-temperature raw material gas header 235; the hydrogen-containing low-temperature converted gas flows out of the furnace body from the low-temperature converted gas outlet 234 and leaves the unit to supply the downstream separation and purification section.

[0039] In the upper part of the second preheating channel for raw material gas, high-temperature converted gas and medium-temperature raw material gas undergo countercurrent heat exchange through a partition wall, achieving secondary preheating of the raw material gas. After the waste heat of the high-temperature converted gas is fully utilized, it flows out of the furnace body 2 from the low-temperature converted gas outlet 234. The high-temperature flue gas generated by the burner 1 passes through the circumferential flue gas guide port 216 and continues to flow downward along the internal channel of the furnace body 2. In the lower part of the second preheating channel for raw material gas, the high-temperature flue gas washes over the raw material gas preheating tube bundle 232, achieving tertiary preheating of the raw material gas. The raw material gas is preheated from medium temperature to high temperature in the second preheating channel for raw material gas, and finally discharged from the high-temperature raw material gas outlet 238 through the annular high-temperature raw material gas header 236. The high-temperature raw material gas discharged from the high-temperature raw material gas outlet 238 can be directly introduced into the reaction raw material inlet 212 as raw material for steam reforming reaction.

[0040] The steam generating section is located at the lower part of the furnace body 2 and includes multiple steam generating heat exchange tube bundles 221, a water collection tank 222, a steam header 223, a feedwater inlet 224, a steam transition pipe 225, an inverted conical guide plate 226, a flue gas outlet 227, and a radial support plate 228. The steam generating section is arranged entirely inside the raw material gas preheating tube bundle 232, and the water collection tank 222 is located inside the annular high-temperature raw material gas header 236. Multiple steam generating heat exchange tube bundles 221 are arranged circumferentially. The upper end of the steam generating heat exchange tube bundle 221 is connected to the steam header 223, and the lower end of the steam generating heat exchange tube bundle 221 is connected to the water collection tank 222. The steam header 223 is located below the reforming reaction tube 211 and the burner 1, and the flue gas outlet 227 is located at the bottom center of the furnace body 1. The steam header 223 is connected to a steam jacket 241 through the steam transition pipe 225, and a saturated steam outlet 240 is provided on the steam jacket 241.

[0041] Specifically, softened water flows from the feedwater inlet 224 through the water collection tank 222 into the steam generating heat exchange tube bundle 221. The steam generating heat exchange tube bundle 221 consists of multiple vertically arranged tubes. High-temperature flue gas flows through the feed gas preheating tube bundle 232 and then enters the steam generating section. The high-temperature flue gas washes over the steam generating heat exchange tube bundle 221, thereby heating the feedwater to generate saturated steam. The saturated steam flows through the steam header 223 and into the steam jacket 241 via the steam transition pipe 225. In the steam jacket 241, the saturated steam absorbs the furnace wall temperature, achieving an increase in dryness. Finally, it flows out from the saturated steam outlet 240 on the steam jacket 241. This saturated steam can be directly introduced into the reaction feedstock inlet 212 as a feedstock for the steam reforming reaction. After the waste heat of the high-temperature flue gas is fully utilized, it is finally discharged from the flue gas outlet 227. The steam generating heat exchange tube bundle 221 uses finned tubes arranged in a staggered pattern.

[0042] For example, such as Figure 3 As shown, the steam header 223 is fixed to the inner wall of the annular cavity by multiple radial support plates 228. The radial support plates 228 are spaced apart in the circumferential direction and are welded to the outer wall of the steam header 223 and the inner wall of the annular cavity 231. The space between the steam header 223 and the reforming reaction section is filled with refractory mud to prevent the steam header 223 from being burned by high-temperature flue gas.

[0043] For example, such as Figure 4 , Figure 5As shown, the steam header 223 is connected to the steam jacket 241 via multiple steam transition pipes 225. The steam transition pipes 225 are evenly arranged circumferentially around the steam header 223 to uniformly introduce the steam generated within the steam header 223 into the steam jacket 241, achieving orderly distribution and transition of the steam. The steam header 223 is equipped with a guide plate 226; in this example, an inverted conical guide plate is used. This inverted conical guide plate provides a curved path guide for the steam movement, preventing steam from accumulating at the top of the steam header 223 and causing heat transfer deterioration, while simultaneously accelerating steam discharge.

[0044] For example, Figure 4 and Figure 2 As shown, a spiral guide plate 239 is provided inside the steam jacket 241. The spiral guide plate 239 is used to guide the steam to form a spiral flow along the axial direction of the furnace body 2, suppress the short-circuit flow of steam, extend the steam flow path, and improve the steam dryness.

[0045] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. An integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas, characterized in that, The furnace includes a burner (1) and a furnace body (2). The burner (1) is located on the upper part of the furnace body (2). A first preheating channel for raw material gas is provided in the burner (1). The furnace body (2) includes a reforming reaction section, a steam generation section, and a second preheating channel for raw material gas. The reforming reaction section is located above the steam generation section and is constructed as an integrated unit. The burner is located inside the reforming reaction section. The second preheating channel for raw material gas is located outside the reforming reaction section and the steam generation section. The gas outlet of the reforming reaction section is connected to the high-temperature conversion gas inlet of the second preheating channel for raw material gas. A low-temperature raw material gas inlet and a medium-temperature raw material gas outlet are provided on the first preheating channel for raw material gas. A medium-temperature raw material gas inlet is provided on the second preheating channel for raw material gas and connected to the medium-temperature raw material gas outlet of the first preheating channel for raw material gas. A high-temperature raw material gas outlet is provided on the second preheating channel for raw material gas and connected to the raw material inlet of the reforming reaction section. The flue gas passage of the burner (1) is connected to the second preheating channel for raw material gas. The steam generation section is located at the end of the flue gas passage. The flue gas flows sequentially through the second preheating channel for raw material gas and the steam generation section.

2. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 1, characterized in that, The burner (1) includes a premixed gas inlet (101), a flow equalization orifice plate (102), an upper part of an upper annular raw gas header (103), a lower part of an upper annular raw gas header (104), a lower annular raw gas header (105), an inner tube (106), and an outer tube (107); the inner tube (106) and the outer tube (107) are coaxially arranged to form a sleeve, and the inner tube (106) and the outer tube (107) are arranged around the flow equalization orifice plate (102); the upper exposed part of the burner (1) is provided with an upper The annular raw material gas collector has a lower annular raw material gas collector (105) in the part of the burner (1) that extends into the furnace body (2). A partition is set in the middle of the upper annular raw material gas collector to divide the upper annular raw material gas collector into an upper part (103) and a lower part (104). A low temperature raw material gas inlet (108) is opened on the side of the upper part (103) and a medium temperature raw material gas outlet (109) is opened on the side of the lower part (104).

3. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 2, characterized in that, The inner tube (106) and the gap between the inner tube (106) and the outer tube (107) constitute the first preheating channel for raw material gas. The outer tube (107) connects the lower annular raw material gas header (105) and the lower part (104) of the upper annular raw material gas header. The two ends of the inner tube (106) connect the lower annular raw material gas header (105) and the upper part (103) of the upper annular raw material gas header.

4. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 1, characterized in that, The second preheating channel for raw material gas includes an annular cavity (231), multiple raw material gas preheating tube bundles (232), an annular medium-temperature raw material gas collector (235), and an annular high-temperature raw material gas collector (236). The annular cavity (231) is located outside the reforming reaction section, and the annular medium-temperature raw material gas collector (235) is arranged outside the annular reaction raw material collector (214). A high-temperature conversion gas inlet (233) is provided on the annular cavity (231), and the annular cavity (231) is connected to the high-temperature conversion gas inlet (236). 33) A low-temperature conversion gas outlet (234) is set on the opposite side, and a high-temperature conversion gas inlet (233) is connected to the gas outlet of the reforming reaction section. The upper end of the raw material gas preheating tube bundle (232) is connected to the annular medium-temperature raw material gas header (235), and the lower end of the raw material gas preheating tube bundle (232) is connected to the annular high-temperature raw material gas header (236). The raw material gas outlet of the first preheating channel of the raw material gas is connected to the medium-temperature raw material gas inlet (237). The heat exchange tubes of the raw material gas preheating tube bundle (232) are bare tubes or finned tubes.

5. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 4, characterized in that, The annular cavity (231) divides the second preheating channel of the raw material gas into upper and lower parts. The heat release medium in the upper part of the second preheating channel of the raw material gas is high-temperature conversion gas, and the heat release medium in the lower part of the second preheating channel of the raw material gas is flue gas.

6. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 1, characterized in that, The steam generation section includes multiple steam generation heat exchange tube bundles (221), a water collection tank (222), a steam header (223), a steam transition pipe (225), a flue gas outlet (227), and a radial support plate (228). The water collection tank (222) is located at the bottom of the furnace body (2). Multiple steam generation heat exchange tube bundles (221) are arranged circumferentially. The upper end of the steam generation heat exchange tube bundle (221) is connected to the steam header (223), and the lower end of the steam generation heat exchange tube bundle (221) is connected to the water collection tank (222). The water collection tank (222) A water inlet (224) is provided on the top, a steam header (223) is located below the reforming reaction section, and a flue gas outlet (227) is located at the bottom center of the furnace body (1). The steam header (223) is connected to a steam jacket (241) through a steam transition pipe (225), and a saturated steam outlet (240) is provided on the steam jacket (241). The steam header (223) is fixed to the inner wall of the annular cavity by multiple radial support plates (228). The heat exchange tubes of the steam generating heat exchange tube bundle (221) are finned tubes and are arranged in a staggered manner.

7. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 6, characterized in that, The steam header (223) is equipped with a guide plate (226), which is an inverted cone-shaped guide plate.

8. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 6, characterized in that, The steam jacket (241) is equipped with a spiral guide plate (239), and the saturated steam outlet (240) is connected to the raw material inlet of the reforming reaction section.

9. The integrated steam reforming hydrogen production unit suitable for low-calorific-value feed gas according to claim 1, characterized in that, The reforming reaction section includes multiple reforming reaction tubes (211), an annular reaction feedstock header (214), and an annular conversion gas header (215). The annular reaction feedstock header (214) is provided with a reaction feedstock inlet (212), the annular conversion gas header (215) is located outside the annular reaction feedstock header (214), and the annular conversion gas header (215) is provided with a high-temperature conversion gas outlet (213). The reforming reaction tubes (211) are arranged circumferentially around the burner (1). The reforming reaction tubes (211) are serpentine reversing tubes, and a catalytic bed is provided inside the reforming reaction tubes (211). A circumferential flue gas guide port (216) is provided at the bottom of the reforming reaction section. The circumferential flue gas guide port (216) connects the burner (1) and the second preheating channel of the feedstock gas. The reforming reaction tubes (211) pass through the flue gas guide port (216).

10. An integrated steam reforming method for hydrogen production suitable for low-calorific-value feed gas, characterized in that, The integrated steam reforming hydrogen production unit based on any one of claims 1-9, suitable for low-calorific-value feed gas, comprises: After the premixed gas enters the burner (1) and is ignited, a continuous and stable combustion flame surface is formed on the outer surface of the burner (1). The heat released during the combustion process is transferred to the reforming reaction section in the form of flame radiation heat, and high-temperature flue gas is generated at the same time. Low-temperature raw gas enters the first preheating channel of raw gas, absorbs heat from the burner (1), and cools the burner (1). The low-temperature raw gas absorbs heat to obtain medium-temperature raw gas. The raw gas and steam enter the reforming reaction section to generate high-temperature conversion gas. The high-temperature conversion gas and high-temperature flue gas enter the second preheating channel of raw gas to heat the medium-temperature raw gas. The medium-temperature raw gas enters the second preheating channel of raw gas and is heated to become high-temperature raw gas. Feedwater enters the steam generation section. In the steam generation section, the feedwater is heated by the flue gas to form steam. The steam and raw gas enter the reforming reaction section together. The flue gas flows out from the burner (1) and passes through the second preheating channel of raw gas and the steam generation section in sequence before being discharged.

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