Ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption function
By designing an ammonia decomposition hydrogen production-fuel cell coupling system and utilizing the adsorbent in the ammonia absorber to absorb ammonia, the problem of expensive separation equipment in traditional ammonia hydrogen production systems is solved, and efficient and environmentally friendly hydrogen utilization and energy recovery are achieved.
Patent Information
- Application Number
- CN202422594101.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-27
- Publication Date
- 2025-09-09
- Estimated Expiration
- 2034-10-27
AI Technical Summary
Traditional ammonia-to-hydrogen systems require expensive hydrogen purification and separation equipment, which limits the widespread application of ammonia-to-hydrogen driven fuel cell technology.
A coupled ammonia decomposition hydrogen production-fuel cell system with residual ammonia absorption is designed. Through scientific design, efficient utilization of the product gas of ammonia decomposition hydrogen production is achieved. The system includes a liquid ammonia source, a gasifier, an ammonia decomposition reactor, an ammonia absorber and a fuel cell. The adsorbent in the ammonia absorber is used to absorb ammonia, simplifying the equipment structure and improving energy efficiency.
It significantly reduces the separation cost of the system, improves energy efficiency, simplifies equipment, reduces flue gas emissions and environmental pollution, and achieves efficient utilization of hydrogen and environmentally friendly emissions.
Smart Images
Figure CN223321292U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of hydrogen energy, in particular to an ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption. Background Art
[0002] With the continuous growth of global energy demand and increasing awareness of environmental protection, hydrogen energy, as a clean and efficient form of energy, has attracted widespread attention. Hydrogen energy has a wide range of applications, with powering downstream loads through fuel cells being a key use case. However, the storage and transportation of hydrogen remain key factors hindering its application.
[0003] Ammonia, as a good hydrogen carrier, is considered a promising medium for hydrogen storage and transportation due to its high hydrogen content and ease of liquefaction, storage, and transportation. Therefore, ammonia-based hydrogen fuel cell technology has become a hot topic of research.
[0004] However, traditional ammonia-to-hydrogen systems require costly hydrogen purification and separation equipment, which limits the widespread application of ammonia-to-hydrogen fuel cell technology. Further development in this field is needed to further optimize the system layout and integrate fuel cells into the overall system, rather than simply treating them as downstream components of the ammonia-to-hydrogen system. Utility Model Content
[0005] In response to the shortcomings of the existing technology, the utility model provides an ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption. Through scientific design, the efficient utilization of the ammonia decomposition hydrogen production product gas is achieved, while reducing the system cost and improving energy efficiency.
[0006] The utility model adopts the following technical solutions:
[0007] An ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption includes a liquid ammonia source, a vaporizer, a first heat exchanger, an ammonia decomposition reactor, an ammonia absorber, a hydrogen and nitrogen buffer bottle, and a fuel cell; the liquid ammonia source is connected to the vaporizer for gasifying liquid ammonia into ammonia; the first heat exchanger includes a first heat exchange ammonia channel and a first heat exchange product gas channel, the ammonia decomposition reactor includes an ammonia decomposition reaction ammonia channel and an ammonia decomposition reaction flue gas channel, the outlet of the vaporizer is connected to the inlet of the first heat exchange ammonia channel, the outlet of the first heat exchange ammonia channel is connected to the inlet of the ammonia decomposition reaction ammonia channel, and the The ammonia gas after heat exchange in the first heat exchanger is passed into the ammonia decomposition reactor for ammonia decomposition; the outlet of the ammonia channel of the ammonia decomposition reaction is connected with the inlet of the first heat exchange product gas channel, and the outlet of the first heat exchange product gas channel is connected with the inlet of the ammonia absorber. The product mixed gas after decomposition in the ammonia decomposition reactor serves as the heat exchange medium of the first heat exchanger and exchanges heat with the ammonia gas passing through the first heat exchange ammonia channel, and then passes into the ammonia absorber for ammonia absorption and purification; the outlet of the ammonia absorber is buffered by the hydrogen and nitrogen buffer bottle and then connected to the negative electrode of the fuel cell to provide fuel hydrogen for the fuel cell.
[0008] The fuel cell includes a battery positive electrode, a battery negative electrode, a battery air channel, a battery gas channel and a battery ion exchange membrane. The battery positive electrode and the battery negative electrode are separated by the battery ion exchange membrane to form two independent reaction areas. The battery air channel is arranged outside the battery positive electrode and is conductive to the battery positive electrode. External air enters the battery positive electrode area through the battery air channel. The battery gas channel is arranged outside the battery negative electrode and is conductive to the battery negative electrode. Gas from the outlet of the ammonia absorber enters the battery negative electrode area through the battery gas channel.
[0009] The ammonia absorber contains an ammonia absorption or adsorbent.
[0010] Preferably, the ammonia absorption or adsorbent is one of acetic acid, acidic molecular sieve, sodium chloride aqueous solution, and calcium chloride.
[0011] The product gas purified by the ammonia absorber 7 enters the hydrogen and nitrogen buffer bottle, and the volume ratio of ammonia contained in the gas at the outlet of the ammonia absorber is not higher than 0.1 ppm.
[0012] The system also includes a second heat exchanger and a burner. The second heat exchanger includes a second heat exchange air channel and a second heat exchange flue gas channel. The outlet of the burner is connected to the inlet of the ammonia decomposition reaction flue gas channel to provide heat energy for the decomposition of ammonia in the ammonia decomposition reactor. The outlet of the ammonia decomposition reaction flue gas channel is connected to the inlet of the second heat exchange flue gas channel to preheat the air entering the second heat exchange air channel. The outlet of the second heat exchange flue gas channel is connected to the flue gas treatment and release unit to treat and release the flue gas after combustion and heat exchange.
[0013] The system further includes an air compressor, the outlet of the air compressor is divided into two paths, one path is connected to the inlet of the second heat exchange air channel, and the other path is connected to the positive electrode of the fuel cell.
[0014] The system also includes a hydrogen tank and an air pump. The outlet of the hydrogen tank is connected to the negative electrode of the fuel cell through the air pump. The hydrogen in the hydrogen tank is pumped into the fuel cell through the air pump. The pumped hydrogen enters the negative electrode of the fuel cell through the air inlet of the fuel cell gas channel and flows out from the air outlet of the fuel cell gas channel into the hydrogen tank.
[0015] The outlet of the hydrogen tank is also connected to the inlet of the burner; the hot air after heat exchange in the second heat exchanger and the product mixed gas discharged through the first heat exchange product gas channel are connected to the inlet of the burner, and the gases are mixed in the burner and ignited to burn to produce high-temperature flue gas.
[0016] The technical solution of this utility model has the following advantages:
[0017] A. This utility model efficiently absorbs residual ammonia from the product gas produced by ammonia decomposition to produce hydrogen, avoiding the expensive nitrogen and hydrogen separation process used in traditional methods and significantly reducing the system's separation costs. The hydrogen in the product gas meets the long-life requirements of the fuel cell.
[0018] B. This utility model replaces the fuel cell's hydrogen recycling system with a hydrogen combustion heating system, simplifying the equipment while improving overall system integration and energy efficiency. This design further strengthens the coupling between the ammonia decomposition hydrogen production unit and the fuel cell unit, achieving efficient energy utilization.
[0019] C. Through scientific design, the system of this utility model not only simplifies the equipment, but also reduces smoke emissions and environmental pollution. After the smoke passes through the treatment and release unit, it can be discharged into the atmosphere in a more environmentally friendly way. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the specific implementation methods of the present invention, the following will briefly introduce the drawings required for use in the specific implementation methods. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0021] Figure 1 Schematic diagram of the overall structure of the ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption.
[0022] The following are marked in the figure:
[0023] 1-Liquid ammonia source; 2-Gasifier; 3-First heat exchanger, 31-First heat exchange ammonia channel, 32-First heat exchange product gas channel; 4-Ammonia decomposition reactor, 41-Ammonia decomposition reaction ammonia channel, 42-Ammonia decomposition reaction flue gas channel; 5-Second heat exchanger, 51-Second heat exchange air channel, 52-Second heat exchange flue gas channel; 6-Burner; 7-Ammonia absorber; 8-Hydrogen and nitrogen buffer bottle; 9-Hydrogen tank; 10-Air pump; 20-Fuel cell, 201-Battery positive electrode, 202-Battery negative electrode, 203-Battery air channel, 204-Battery hydrogen channel, 205-Battery ion exchange membrane; 30-Air compressor; 40-Flue gas treatment and release unit. DETAILED DESCRIPTION
[0024] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.
[0025] like Figure 1As shown, this embodiment provides an ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption, comprising a liquid ammonia source 1, a vaporizer 2, a first heat exchanger 3, an ammonia decomposition reactor 4, an ammonia absorber 7, a hydrogen and nitrogen buffer bottle 8, and a fuel cell 20. The liquid ammonia source 1 is connected to the vaporizer 2 for gasifying the liquid ammonia into ammonia. The first heat exchanger 3 includes a first heat exchange ammonia channel 31 and a first heat exchange product gas channel 32. The ammonia decomposition reactor 4 includes an ammonia decomposition reaction ammonia channel 41 and an ammonia decomposition reaction flue gas channel 42. The outlet of the vaporizer 2 is connected to the inlet of the first heat exchange ammonia channel 31, and the outlet of the first heat exchange ammonia channel 31 is connected to the inlet of the ammonia decomposition reaction ammonia channel 41. The ammonia after heat exchange in the first heat exchanger 3 is passed into the ammonia decomposition reactor 4 for ammonia decomposition. The outlet of the ammonia channel 41 of the ammonia decomposition reaction is connected to the inlet of the first heat exchange product gas channel 32, and the outlet of the first heat exchange product gas channel 32 is connected to the inlet of the ammonia absorber 7. The product mixed gas after decomposition by the ammonia decomposition reactor 4 is used as the heat exchange medium of the first heat exchanger 3 and heat-exchanged with the ammonia passing through the first heat exchange ammonia channel 31, and then enters the ammonia absorber 7 for ammonia absorption and purification. The outlet of the ammonia absorber 7 is connected to the negative electrode of the fuel cell 20 after being buffered by the hydrogen and nitrogen buffer bottle 8, providing fuel hydrogen for the fuel cell 20. The utility model avoids the high nitrogen and hydrogen separation process in the traditional method by efficiently absorbing the residual ammonia in the product gas of ammonia decomposition to produce hydrogen, and significantly reduces the separation cost of the system. The hydrogen in the product gas meets the long-life use conditions of the fuel cell.
[0026] Furthermore, the fuel cell 20 includes a battery positive electrode 201, a battery negative electrode 202, a battery air channel 203, a battery gas channel 204 and a battery ion exchange membrane 205. The battery positive electrode 201 and the battery negative electrode 202 are separated by the battery ion exchange membrane 205 to form two independent reaction areas. The battery air channel 203 is arranged on the outside of the battery positive electrode 201 and is connected to the battery positive electrode 201. External air enters the battery positive electrode 201 area through the battery air channel 203. The battery gas channel 204 is arranged on the outside of the battery negative electrode 202 and is connected to the battery negative electrode 202. The gas from the outlet direction of the ammonia absorber 7 enters the battery negative electrode 202 area through the battery gas channel 204.
[0027] It should be noted that although this embodiment uses hydrogen containing nitrogen as the cathode of fuel cell 20 rather than high-purity hydrogen, nitrogen does not chemically damage the fuel cell. Therefore, the presence of nitrogen may result in a certain reduction in fuel cell power. However, from the perspective of the entire coupled system, the overall efficiency is not reduced due to the savings in expensive nitrogen and hydrogen separation equipment, cost, and weight. The fuel gas exiting fuel cell cathode 202 can be used as low-quality fuel and enter combustion chamber 6, rather than being fully recycled and returned to gas channel 204. Therefore, nitrogen accumulation and continuous dilution of the hydrogen in the fuel are avoided.
[0028] Ammonia absorber 7 contains an ammonia absorber or adsorbent, including but not limited to acetic acid, acidic molecular sieves, sodium chloride aqueous solution, calcium chloride, etc. The product gas purified by ammonia absorber 7 enters hydrogen and nitrogen buffer bottle 8. The gas at the outlet of ammonia absorber 7 contains no more than 0.1 ppm of ammonia by volume.
[0029] The system also includes a second heat exchanger 5 and a burner 6. The second heat exchanger 5 includes a second heat exchange air channel 51 and a second heat exchange flue gas channel 52. The outlet of the burner 6 is connected to the inlet of the ammonia decomposition reaction flue gas channel 42, providing heat energy for the decomposition of ammonia in the ammonia decomposition reactor 4. The outlet of the ammonia decomposition reaction flue gas channel 42 is connected to the inlet of the second heat exchange flue gas channel 52, used to preheat the air entering the second heat exchange air channel 51. The outlet of the second heat exchange flue gas channel 52 is connected to the flue gas treatment and release unit 40, used to treat and release the flue gas after combustion and heat exchange. The utility model realizes efficient energy recovery and utilization by performing multi-stage heat exchange between the heat generated during the ammonia decomposition process and the heat generated during the combustion process. In particular, the high-temperature flue gas generated by combustion is used to preheat the ammonia entering the ammonia decomposition reactor, reducing energy consumption and improving the overall thermal efficiency of the system.
[0030] The system also includes an air compressor 30, a hydrogen tank 9 and an air pump 10. The outlet of the air compressor 30 is divided into two paths, one path is connected to the inlet of the second heat exchange air channel 51, and the other path is connected to the battery positive electrode 201 of the fuel cell 20. The outlet of the hydrogen tank 9 is connected to the battery negative electrode 202 of the fuel cell 20 through the air pump 10. The hydrogen in the hydrogen tank 9 is pumped into the fuel cell 20 through the air pump 10. The pumped hydrogen enters the battery negative electrode 202 through the air inlet of the battery gas channel 204 of the fuel cell 20, and flows out from the air outlet of the battery gas channel 204 into the hydrogen tank 9. The outlet of the hydrogen tank 9 is also connected to the inlet of the burner 6. The hot air after heat exchange in the second heat exchanger 5 and the product mixed gas discharged through the first heat exchange product gas channel 32 are connected to the inlet of the burner 6. After the gases are mixed in the burner 6, they are ignited and burned to produce high-temperature flue gas.
[0031] This utility model replaces the fuel cell's hydrogen recycling system with a hydrogen combustion heating system, simplifying the equipment while improving overall system integration and energy efficiency. This design further strengthens the coupling between the ammonia decomposition hydrogen production unit and the fuel cell unit, achieving efficient energy utilization. Through scientific design, this system not only simplifies the equipment but also reduces flue gas emissions and environmental pollution. After passing through the treatment and release units, the flue gas can be discharged into the atmosphere in a more environmentally friendly manner.
[0032] Any matters not described in this utility model are applicable to the prior art.
[0033] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.
Claims
1. An ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption, characterized in that: The invention comprises a liquid ammonia source (1), a vaporizer (2), a first heat exchanger (3), an ammonia decomposition reactor (4), an ammonia absorber (7), a hydrogen and nitrogen buffer bottle (8) and a fuel cell (20); the liquid ammonia source (1) is connected to the vaporizer (2) for gasifying liquid ammonia into ammonia; the first heat exchanger (3) comprises a first heat exchange ammonia channel (31) and a first heat exchange product gas channel (32); the ammonia decomposition reactor (4) comprises an ammonia decomposition reaction ammonia channel (41) and an ammonia decomposition reaction flue gas channel (42); the outlet of the vaporizer (2) is connected to the inlet of the first heat exchange ammonia channel (31); the outlet of the first heat exchange ammonia channel (31) is connected to the inlet of the ammonia decomposition reaction ammonia channel (41); and the ammonia decomposition reaction flue gas channel (42) is connected to the first heat exchange ammonia channel (31). Ammonia gas after heat exchange in a heat exchanger (3) is introduced into the ammonia decomposition reactor (4) for ammonia decomposition; the outlet of the ammonia decomposition reaction ammonia channel (41) is connected to the inlet of the first heat exchange product gas channel (32), and the outlet of the first heat exchange product gas channel (32) is connected to the inlet of the ammonia absorber (7); the product mixed gas after decomposition in the ammonia decomposition reactor (4) is used as the heat exchange medium of the first heat exchanger (3) and is then exchanged with the ammonia gas passing through the first heat exchange ammonia channel (31) and introduced into the ammonia absorber (7) for ammonia absorption and purification; the outlet of the ammonia absorber (7) is buffered by the hydrogen and nitrogen buffer bottle (8) and then connected to the negative electrode of the fuel cell (20), thereby providing fuel hydrogen for the fuel cell (20).
2. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 1, characterized in that: The fuel cell (20) comprises a battery positive electrode (201), a battery negative electrode (202), a battery air channel (203), a battery gas channel (204) and a battery ion exchange membrane (205). The battery positive electrode (201) and the battery negative electrode (202) are separated by the battery ion exchange membrane (205) to form two independent reaction areas. The battery air channel (203) is arranged outside the battery positive electrode (201) and is in communication with the battery positive electrode (201). External air enters the battery positive electrode (201) area through the battery air channel (203). The battery gas channel (204) is arranged outside the battery negative electrode (202) and is in communication with the battery negative electrode (202). Gas from the outlet direction of the ammonia absorber (7) enters the battery negative electrode (202) area through the battery gas channel (204).
3. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 1, characterized in that: The ammonia absorber (7) contains an ammonia absorber or adsorbent, and the ammonia absorber or adsorbent is one of acetic acid, acidic molecular sieve, sodium chloride aqueous solution, and calcium chloride.
4. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 2, characterized in that: The system further comprises a second heat exchanger (5) and a burner (6), wherein the second heat exchanger (5) comprises a second heat exchange air channel (51) and a second heat exchange flue gas channel (52), wherein the outlet of the burner (6) is connected to the inlet of the ammonia decomposition reaction flue gas channel (42) to provide heat energy for the decomposition of ammonia in the ammonia decomposition reactor (4), the outlet of the ammonia decomposition reaction flue gas channel (42) is connected to the inlet of the second heat exchange flue gas channel (52) to preheat the air entering the second heat exchange air channel (51), and the outlet of the second heat exchange flue gas channel (52) is connected to the flue gas treatment and release unit (40) to treat and release the flue gas after combustion and heat exchange.
5. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 4, characterized in that: The system further comprises an air compressor (30), the outlet of the air compressor (30) being divided into two paths, one path being connected to the inlet of the second heat exchange air channel (51), and the other path being connected to the positive electrode (201) of the fuel cell (20).
6. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 5, characterized in that: The system further comprises a hydrogen tank (9) and an air pump (10); the outlet of the hydrogen tank (9) is connected to the battery negative electrode (202) of the fuel cell (20) through the air pump (10); the hydrogen in the hydrogen tank (9) is pumped into the fuel cell (20) through the air pump (10); the pumped hydrogen enters the battery negative electrode (202) through the air inlet of the battery gas channel (204) of the fuel cell (20), and flows out from the air outlet of the battery gas channel (204) into the hydrogen tank (9).
7. The ammonia decomposition hydrogen production-fuel cell coupling system with residual ammonia absorption according to claim 6, characterized in that: The outlet of the hydrogen tank (9) is also connected to the inlet of the burner (6); the hot air after heat exchange in the second heat exchanger (5) and the product mixed gas discharged through the first heat exchange product gas channel (32) are connected to the inlet of the burner (6), and the gases are mixed in the burner (6) and ignited to burn to produce high-temperature flue gas.