Energy-saving methanol hydrogen production equipment

Abstract

The application belongs to hydrogen production equipment technical field, particularly relates to energy-saving methanol hydrogen production equipment, including raw material tank, raw material tank is sequentially provided with evaporation tank and reaction tank below, raw material tank is provided with feed inlet, raw material tank is connected with feed pipe, evaporation heater is arranged below the inside of evaporation tank, cage type heat exchanger is also arranged in evaporation tank, cage type heat exchanger includes heat exchange pipe that is arranged in evaporation tank and surrounds evaporation heater, heat exchange pipe includes inner tube and outer tube that is sleeved on inner tube, the upper portion of evaporation tank is provided with steam outlet, steam outlet is connected with the upper portion of outer tube, reaction tank includes heat preservation shell, reaction heater is arranged in heat preservation shell, reaction heater is arranged around reaction tube, one end of reaction tube is connected with the lower portion of outer tube, the other end of reaction tube is connected with the lower portion of inner tube, the upper end of inner tube passes through raw material tank and extends to the upper portion of raw material tank, three-stage waste heat recovery is realized, compact structure, small heat loss, the problem of low energy utilization, high energy consumption and bulky structure is solved.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen production equipment technology, specifically relating to an energy-saving methanol-to-hydrogen equipment. Background Technology

[0002] Methanol-to-hydrogen technology, as an efficient and clean method for hydrogen production, has wide applications in chemical, energy, and fuel cell fields. Existing methanol-to-hydrogen equipment typically includes a feedstock tank, an evaporator, and a reaction tank. Its basic workflow is as follows: methanol feedstock is heated and vaporized in the evaporator and then directly enters the reaction tank for reforming reaction, generating high-temperature reaction products rich in hydrogen.

[0003] However, existing equipment has the following technical shortcomings in practical applications: First, the thermal energy utilization rate is low, and the system energy consumption is high. High-temperature reaction products (typically 250-300℃) are directly discharged or simply cooled after the reaction, and the large amount of waste heat they carry is not effectively recovered. The evaporator needs to continuously consume electricity or fuel to maintain the methanol vaporization temperature, and the reaction tank also requires significant external heating to maintain the reforming reaction temperature, resulting in persistently high overall energy consumption for the entire hydrogen production system and making it difficult to reduce hydrogen production costs.

[0004] Secondly, the equipment has a bulky structure and significant heat loss. In traditional equipment, separate heat exchangers are usually required for processes such as raw material preheating, steam superheating, and reaction product cooling, with each component connected by external pipelines. This decentralized layout not only results in a large footprint and complex piping, but also leads to significant heat loss of high-temperature fluids during long-distance transport, further exacerbating energy waste.

[0005] Third, the reaction efficiency needs to be improved. The methanol vapor is not sufficiently superheated before entering the reaction tube, resulting in a low vapor temperature, which is not conducive to improving the methanol conversion rate and hydrogen yield, thus affecting the overall efficiency of the hydrogen production system.

[0006] Therefore, how to design a methanol-to-hydrogen equipment that can efficiently recover waste heat from reaction products, reduce system energy consumption, has a compact structure, and high reaction efficiency is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes an energy-saving methanol-to-hydrogen equipment, which effectively solves the technical problems raised in the prior art.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: an energy-saving methanol-to-hydrogen equipment, comprising a raw material tank, an evaporator and a reaction tank arranged sequentially below the raw material tank, the raw material tank having a feed inlet, a feed pipe connecting the raw material tank and the evaporator, an evaporation heater arranged at the lower interior of the evaporator, a cage-type heat exchanger also arranged inside the evaporator, the cage-type heat exchanger including a heat exchange tube arranged inside the evaporator and surrounding the evaporation heater, the heat exchange tube including an inner tube and an outer tube sleeved on the inner tube, a steam outlet arranged at the upper part of the evaporator, the steam outlet connected to the upper part of the outer tube, the reaction tank including an insulation shell, a reaction heater arranged inside the insulation shell, a reaction tube arranged around the reaction heater, one end of the reaction tube connected to the lower part of the outer tube, the other end of the reaction tube connected to the lower part of the inner tube, the upper end of the inner tube passing through the raw material tank and extending to the upper part of the raw material tank.

[0009] Furthermore, the reaction tube is U-shaped.

[0010] Furthermore, the lower end of the reaction tube is provided with a detachable bend joint.

[0011] Furthermore, spiral fins are provided between the outer tube and the inner tube.

[0012] Furthermore, a wire mesh demister is installed at the steam outlet, and the outlet of the wire mesh demister is connected to the upper part of the outer pipe.

[0013] Furthermore, the steam outlet is connected to the upper part of the outer pipe via a braided flexible hose, and the reaction pipe is connected to the lower part of the outer pipe via a braided flexible hose.

[0014] Furthermore, the steam outlet is connected to a disc-shaped sub-port, and a lower connection port is provided on the lower side of the disc-shaped sub-port. The lower connection port is connected to the steam outlet. Side interfaces for connecting to the lower connection port are opened around the side of the disc-shaped sub-port, and the side interfaces are respectively connected to the outer pipe.

[0015] Furthermore, the evaporator is characterized by having a partition plate inside, which is disposed between the evaporator heater and the heat exchange tube. The partition plate surrounds the evaporator heater and its upper end is connected to the evaporator. The lower end of the partition plate has a communication gap with the bottom of the evaporator.

[0016] Furthermore, it also includes a heater mounting bracket. The evaporation heater and the reaction heater are both composed of multiple electric heating tubes. The evaporation heater and the reaction heater are both arranged around the heater mounting bracket. The bottom of the evaporation tank is provided with a heating groove that is recessed into the evaporation tank. The evaporation heater is located in the heating groove. The lower part of the heater mounting bracket passes through the insulation shell and is fixedly connected to the insulation shell. A wiring groove is opened in the center of the heater mounting bracket.

[0017] Compared with existing technologies, this invention connects a raw material tank, an evaporator, and a reaction tank in a series from top to bottom, and installs a cage-type heat exchanger consisting of an inner and outer tube inside the evaporator. During operation, methanol vapor flows downwards from the evaporator into the outer tube, then enters the reaction tube for reforming. The resulting high-temperature reaction products flow upwards through the inner tube: first, the vapor in the outer tube is superheated, then it passes through the raw material tank to preheat the low-temperature raw material, achieving the following technical effects: 1. Three-stage waste heat recovery significantly reduces heating energy consumption, approaching self-heating equilibrium; 2. The heat exchanger is integrated into the evaporator, with the inner tube directly connected to the raw material tank, resulting in a compact structure and low heat loss; 3. The superheated steam enters the reaction tube, improving methanol conversion rate and hydrogen yield. This structure solves the problems of low thermal energy utilization, high energy consumption, and bulky structure of existing equipment. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the present invention; Figure 2 for Figure 1 Enlarged view of section A in the middle; Figure 3 for Figure 1 Enlarged view of section B in the middle; Figure 4 for Figure 1 Enlarged view of section C.

[0019] In the diagram: 1. Raw material tank; 11. Feed inlet; 2. Evaporator; 21. Steam outlet; 22. Wire mesh demister; 23. Braided hose one; 24. Braided hose two; 25. Disc-shaped connector; 251. Lower connection port; 252. Side interface; 26. Partition plate; 27. Heating tank; 3. Reaction tank; 31. Insulation shell; 4. Evaporator heater; 5. Cage heat exchanger; 51. Inner tube; 52. Outer tube; 53. Spiral fins; 6. Reaction heater; 7. Reaction tube; 71. Bend joint; 8. Heater mounting bracket; 81. Wiring trough; 12. Feed pipe. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] like Figure 1As shown, an energy-saving methanol-to-hydrogen equipment includes a raw material tank 1, an evaporator 2, and a reaction tank 3, arranged sequentially from top to bottom. A feed inlet 11, connecting to the inside of the raw material tank 1, is welded to the bottom side for injecting low-temperature methanol feedstock into the tank. The raw material tank 1 and the evaporator 2 are connected by a feed pipe 12. The upper part of the feed pipe 12 is welded to the upper part of the raw material tank 1, and the lower end of the feed pipe 12 is welded to the lower part of the evaporator 2. A control valve can be installed on the feed pipe 12 to regulate the methanol feedstock delivery rate.

[0022] An evaporation heater 4 is installed at the lower part of the interior of the evaporator 2 to heat liquid methanol and vaporize it. A cage-type heat exchanger 5 is also installed inside the evaporator 2. This cage-type heat exchanger 5 includes heat exchange tubes arranged around the evaporation heater 4. The heat exchange tubes consist of an inner tube 51 and an outer tube 52 sleeved on the inner tube 51. An annular channel is formed between the inner tube 51 and the outer tube 52 for the flow of methanol vapor. The upper and lower ends of the heat exchange tubes pass through the upper and lower ends of the evaporator 2, respectively. A steam outlet 21 is provided at the upper part of the evaporator 2, which is connected to the upper end of the outer tube 52, allowing the methanol vapor generated by evaporation to enter the annular channel between the outer tube 52 and the inner tube 51.

[0023] The reaction vessel 3 includes an insulation shell 31 to reduce heat loss. A reaction heater 6 is housed inside the insulation shell 31, and a reaction tube 7 is arranged around the reaction heater 6. One end of the reaction tube 7 is connected to the lower opening of the outer tube 52, and the other end is connected to the lower opening of the inner tube 51. The reaction tube 7 is U-shaped to extend the reaction path and increase the heat exchange area. The upper end of the inner tube 51 passes sequentially through the evaporator 2 and the raw material tank 1, ultimately extending to the upper space of the raw material tank 1, serving as the outlet for the reaction products.

[0024] Work process Methanol feedstock enters evaporator 2 from feedstock tank 1 via feed pipe 12, where it vaporizes under the heating of evaporator heater 4, generating methanol vapor. The vapor rises to the upper part of evaporator 2 and enters the annular channel between outer pipe 52 and inner pipe 51 through steam outlet 21, flowing downwards. During this process, the vapor is preheated by the high-temperature reaction products flowing through inner pipe 51, achieving the first superheating. Subsequently, the vapor enters reaction tube 7 from the lower end of outer pipe 52, undergoing a reforming reaction under the auxiliary heating of reaction heater 6, generating high-temperature reaction products rich in hydrogen (temperature approximately 250-300℃). The reaction products enter the lower end of inner pipe 51 from the other end of reaction tube 7, flowing upwards along inner pipe 51. In inner pipe 51, the high-temperature reaction products first transfer heat through the pipe wall to the methanol vapor in outer pipe 52, further superheating it; then, inner pipe 51 passes through evaporator 2 and enters feedstock tank 1, using residual heat to directly preheat the low-temperature methanol feedstock in feedstock tank 1, achieving the second preheating. Finally, the cooled reaction product is discharged from the upper end of the inner tube 51 and enters the subsequent separation and purification unit. Compared with traditional methanol to hydrogen equipment, the present invention has less heat loss during methanol vapor transportation. Example

[0025] To further optimize equipment performance, the present invention also provides the following preferred solutions: Optimization of reaction tube structure: such as Figure 2 As shown, the reaction tube 7 adopts a U-shaped design, with a detachable bend joint 71 at its lower end. This joint facilitates the disassembly and replacement of the catalyst, and also facilitates the cleaning and maintenance of the inside of the reaction tube, extending the service life of the equipment.

[0026] Improved heat exchange efficiency: such as Figure 3 As shown, spiral fins 53 are provided in the annular channel between the outer tube 52 and the inner tube 51. The spiral fins 53 can guide the steam to flow along the spiral path, increase the contact time with the inner tube wall, and significantly improve the steam superheating effect.

[0027] Steam purification treatment: such as Figure 4 As shown, a wire mesh demister 22 is installed at the steam outlet 21 to remove liquid droplets entrained in the methanol vapor, ensuring that the steam entering the heat exchanger is dry saturated steam. The outlet of the wire mesh demister 22 is connected to the upper part of the outer pipe 52 via a pipe.

[0028] Flexible connection design: such as Figure 3 , Figure 4 As shown, to compensate for thermal expansion and facilitate installation, the steam outlet 21 is connected to the upper part of the outer pipe 52 via a braided flexible hose 23; the reaction pipe 7 is connected to the lower part of the outer pipe 52 via a braided flexible hose 24. The braided hose has good flexibility and temperature resistance, can absorb thermal stress, and prevent the pipeline from being damaged due to thermal expansion and contraction.

[0029] Multi-tube parallel structure: such as Figure 4 As shown, the steam outlet 21 is connected to a disc-shaped interface 25. The lower side of the disc-shaped interface 25 has a lower connection port 251, which connects to the steam outlet 21; multiple side interfaces 252 are arranged around its side, each side interface 252 connecting to the upper end of an outer pipe 52. Correspondingly, the lower end of each outer pipe 52 is connected to a reaction pipe 7, forming multiple sets of parallel heat exchange-reaction units, significantly improving the equipment's processing capacity.

[0030] Partitions: such as Figure 1 As shown, the evaporator 2 is also equipped with a partition plate 26, which is located between the evaporator heater 4 and the cage heat exchanger 5. The partition plate 26 surrounds the evaporator heater 4, with its upper end sealed to the inner wall of the evaporator 2 and its lower end having a communication gap with the bottom of the evaporator 2. This design divides the interior of the evaporator 2 into a heating zone and a heat exchange zone: the heating zone is located inside the partition plate, where liquid methanol is heated and vaporized; the heat exchange zone is located outside the partition plate, where methanol vapor exchanges heat with the high-temperature products in the inner tube. The partition plate can effectively prevent liquid methanol from splashing onto the heat exchange tubes, avoiding local overheating and coking, while ensuring the uniformity of steam flow.

[0031] Heater mounting structure: such as Figure 1 As shown, both the evaporator heater 4 and the reaction heater 6 consist of multiple electric heating tubes, which are arranged around the heater mounting bracket 8. The bottom of the evaporator tank 2 has a recessed heating groove 27, in which the evaporator heater 4 is located, making the heating area more concentrated and improving thermal efficiency. The lower part of the heater mounting bracket 8 passes through and is fixedly connected to the insulation shell 31. A wiring groove 81 is provided in the center of the bracket to accommodate the power cord of the electric heating tube, facilitating wiring and preventing the wiring from being affected by high temperatures.

[0032] Summary of technical effects Through the above structural design, the present invention achieves the following beneficial effects: Three-stage waste heat recovery: High-temperature reaction products are used sequentially for steam superheating (in the evaporator), raw material preheating (in the raw material tank 1), and auxiliary evaporation, which significantly reduces the energy consumption of the evaporator heater 4 and the reaction heater 6, making the equipment tend to operate in "self-heating equilibrium".

[0033] Compact structure and low heat loss: The heat exchanger is integrated inside the evaporator 2, and the inner tube 51 passes directly through the raw material tank 1, eliminating the need for a separate heat exchanger and external connecting pipelines, reducing the equipment volume and heat dissipation area, and significantly reducing heat loss.

[0034] Improved reaction efficiency: Methanol vapor is fully superheated before entering reaction tube 7, and participates in the reforming reaction at a higher temperature, which is beneficial to improving methanol conversion rate and hydrogen yield.

[0035] Easy maintenance: The U-shaped reaction tube with a detachable bend connector 71 is easy to clean; the braided hose connection compensates for thermal expansion and extends the pipeline life; the partition plate 26 prevents liquid droplet splashing and ensures stable system operation.

[0036] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An energy-saving methanol-to-hydrogen equipment, characterized in that: The system includes a raw material tank, below which are an evaporator and a reaction tank arranged sequentially. The raw material tank has a feed inlet, and a feed pipe connects the raw material tank and the evaporator. An evaporation heater is located inside the lower part of the evaporator, and a cage-type heat exchanger is also installed inside the evaporator. The cage-type heat exchanger includes heat exchange tubes arranged inside the evaporator and surrounding the evaporation heater. The heat exchange tubes include an inner tube and an outer tube sleeved on the inner tube. A steam outlet is provided at the upper part of the evaporator, and the steam outlet is connected to the upper part of the outer tube. The reaction tank includes an insulation shell, inside which is a reaction heater. A reaction tube is arranged around the reaction heater. One end of the reaction tube is connected to the lower part of the outer tube, and the other end of the reaction tube is connected to the lower part of the inner tube. The upper end of the inner tube passes through the raw material tank and extends to the upper part of the raw material tank.

2. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: The reaction tube is U-shaped.

3. The energy-saving methanol-to-hydrogen equipment according to claim 2, characterized in that: The lower end of the reaction tube is equipped with a detachable bend joint.

4. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: Spiral fins are provided between the outer tube and the inner tube.

5. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: The steam outlet is equipped with a wire mesh demister, and the outlet of the wire mesh demister is connected to the upper part of the outer pipe.

6. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: The steam outlet is connected to the upper part of the outer pipe via a braided hose, and the reaction tube is connected to the lower part of the outer pipe via a braided hose.

7. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: The steam outlet is connected to a disc-shaped sub-port, and a lower connection port is provided on the lower side of the disc-shaped sub-port. The lower connection port is connected to the steam outlet. Side interfaces for connecting to the lower connection port are opened around the side of the disc-shaped sub-port, and the side interfaces are respectively connected to the outer pipe.

8. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: The evaporator is also equipped with a partition plate, which is located between the evaporator heater and the heat exchange tube. The partition plate surrounds the evaporator heater and its upper end is connected to the evaporator. The lower end of the partition plate has a communication gap with the bottom of the evaporator.

9. The energy-saving methanol-to-hydrogen equipment according to claim 1, characterized in that: It also includes a heater mounting bracket. The evaporation heater and the reaction heater are both composed of multiple electric heating tubes. The evaporation heater and the reaction heater are both arranged around the heater mounting bracket. The bottom of the evaporation tank is provided with a heating groove that is recessed into the evaporation tank. The evaporation heater is located in the heating groove. The lower part of the heater mounting bracket passes through the insulation shell and is fixedly connected to the insulation shell. A wiring groove is opened in the center of the heater mounting bracket.

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