Efficient hydrogen refueling station system coupled with SOEC hydrogen production device and hydrogen production process

Abstract

The invention discloses an efficient hydrogen production and hydrogen refueling station system coupled with an SOEC hydrogen production device. The efficient hydrogen production and hydrogen refueling station system comprises a photovoltaic unit, an SOEC electrolytic bath, a combustor, a water supply unit, a waste heat recovery unit, an ammonia hydrogen production unit and a hydrogen refueling unit. The photovoltaic unit supplies power to the SOEC electrolytic bath and the ammonia hydrogen production unit, and an anode outlet of the SOEC electrolytic bath is connected with the combustor. The ammonia hydrogen production unit comprises a liquid ammonia tank, an evaporator and an ammonia decomposition reactor, decomposed gas is purified by a temperature swing adsorption device, part of the gas enters a combustor for combustion, and part of the gas is output by a filling machine after being compressed and refrigerated. The waste heat recovery unit recovers waste heat of the combustor and the electrolytic cell, is used for preheating water of the water supply unit and supplying the water to the SOEC electrolytic cell, and meanwhile provides heat energy for the ammonia decomposition reactor. High-temperature SOEC electrolytic hydrogen production and ammonia decomposition hydrogen production are coupled, and waste heat gradient utilization is combined, so that the energy utilization rate of the system is remarkably increased, the hydrogen filling efficiency is optimized, the electrolysis power consumption is reduced, and efficient and stable hydrogen energy production and filling are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen energy equipment, and particularly relates to an efficient hydrogen refueling station system and hydrogen production process coupled with a SOEC hydrogen production device. Background Art

[0002] With the transformation of the global energy structure towards cleaner and lower-carbon forms, hydrogen energy, as an efficient and clean secondary energy source, has received extensive attention. As an important infrastructure in the hydrogen energy industry chain, the efficiency and reliability of hydrogen refueling stations directly affect the popularization and application of hydrogen energy. However, traditional hydrogen refueling stations usually rely on external hydrogen supply (such as through pipelines or transporting hydrogen), which have problems such as high hydrogen supply costs, large transportation losses, and high carbon emissions. At the same time, traditional electrolytic water hydrogen production technologies (such as alkaline electrolyzers or proton exchange membrane electrolyzers) are limited by low efficiency and high energy consumption, and it is difficult to meet the requirements of hydrogen refueling stations for efficient and low-carbon hydrogen production; solid oxide electrolytic cells (SOECs), as a high-temperature electrolysis technology, have advantages such as high energy conversion efficiency and the ability to utilize waste heat for synergistic hydrogen production, and are considered an important direction for future efficient hydrogen production. However, currently, SOEC technology still faces challenges such as insufficient coupling with hydrogen refueling station systems, inadequate utilization of thermal energy, and high system integration complexity in practical applications; therefore, developing a technology that can efficiently couple SOEC hydrogen production devices with hydrogen refueling station systems to achieve integrated operation of hydrogen production, hydrogen storage, and hydrogen refueling is of great significance for reducing the operating costs of hydrogen refueling stations, improving energy utilization efficiency, and promoting the development of the hydrogen energy industry.

[0003] Chinese Patent CN119243177A discloses an efficient large-scale coupled hydrogen production process and system, which couples an alkaline water electrolysis hydrogen production system, an ammonia water distillation system, an ammonia decomposition system, and a hydrogen separation and collection system to avoid problems such as impurity accumulation and decreased electrolysis efficiency caused by the recycling of alkaline liquid in traditional alkaline water electrolysis processes. This process generates volatile ammonia by reacting the alkaline liquid with fixed ammonium in ammonia water through reactive distillation, and then catalytically decomposes it into hydrogen through the ammonia decomposition system, and finally collects the hydrogen produced by water electrolysis as product hydrogen. Although this process improves the electrolysis efficiency and hydrogen production, it still has the following objective defects: 1) The high-temperature ammonia decomposition reaction requires a large amount of thermal energy, increasing energy consumption; 2) The system is complex, and the equipment investment and maintenance costs are relatively high; 3) The process has high quality requirements for alkaline liquid and ammonia water, increasing the complexity of raw material treatment. Summary of the Invention

[0004] Aiming at the defects in the existing hydrogen production systems and processes, such as large energy consumption, complex system settings, high maintenance costs, and complex hydrogen production steps; an efficient hydrogen refueling station system and hydrogen production process coupled with a SOEC hydrogen production device are provided, which have high hydrogen production efficiency and low energy consumption, and realize multi-level utilization of energy and overall performance improvement through waste heat recovery.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows: An efficient hydrogen production and hydrogen refueling station system coupled with an SOEC hydrogen production device, comprising a photovoltaic unit, an SOEC electrolyzer, a burner, a water supply unit, a waste heat recovery unit, an ammonia hydrogen production unit, and a hydrogen refueling unit; the photovoltaic unit is electrically connected to the SOEC electrolyzer and the ammonia hydrogen production unit respectively; the anode outlet of the SOEC electrolyzer communicates with the burner; the ammonia hydrogen production unit includes a liquid ammonia tank and an ammonia decomposition reactor, and the liquid ammonia tank is directly connected to the ammonia decomposition reactor; an evaporator is arranged between the liquid ammonia tank and the ammonia decomposition reactor; the hydrogen refueling unit includes a temperature swing adsorption device, a compressor, a refrigerator, and a filling machine; the inlet of the temperature swing adsorption device is simultaneously connected to the cathode outlet of the SOEC electrolyzer and the decomposition gas outlet of the ammonia decomposition reactor; the outlet of the temperature swing adsorption device is respectively connected to the burner and the compressor; the gas discharged from the ammonia decomposition reactor and entering the temperature swing adsorption device is discharged from the temperature swing adsorption device and then enters the burner for combustion; the gas discharged from the SOEC electrolyzer and entering the temperature swing adsorption device is discharged from the temperature swing adsorption device and then enters the compressor for compression; the compressor is sequentially connected to the refrigerator and the filling machine; the waste heat recovery unit is directly connected to the burner, and the water supply unit is connected to the waste heat recovery unit; the waste heat recovery unit is connected to the SOEC electrolyzer and is electrically connected to the ammonia decomposition reactor; the water in the water supply unit enters the SOEC electrolyzer after passing through the waste heat recovery unit.

[0006] Further, the photovoltaic unit includes a photovoltaic module, an inverter, and a first lithium battery. The photovoltaic module is connected to the inverter, and the inverter is electrically connected to the SOEC electrolyzer and the ammonia decomposition reactor; the first lithium battery is electrically connected to the inverter.

[0007] Further, it further includes a first heat exchanger and a second heat exchanger. The anode outlet of the SOEC electrolyzer is connected to the first heat exchanger, and the cathode outlet of the SOEC electrolyzer and the second heat exchanger are connected; the water supply unit includes a water tank and a water pump, the water tank and the water pump are directly connected, and the water pump is respectively connected to the first heat exchanger and the second heat exchanger; the first heat exchanger is also directly connected to the temperature swing adsorption device, and the second heat exchanger is also directly connected to the burner.

[0008] Further, the temperature swing adsorption device and the compressor are connected in series, the compressor is then connected in series with the refrigerator, and the refrigerator is then connected in series with the filling machine; a first buffer tank is arranged between the temperature swing adsorption device and the compressor, and a second buffer tank is arranged between the compressor and the refrigerator.

[0009] Further, the temperature swing adsorption device includes two adsorption columns connected in parallel with each other. An inlet valve is correspondingly provided at the inlet of each adsorption column, and an outlet valve is also correspondingly provided at the outlet of each adsorption column. One of the adsorption columns is used for adsorptive purification of the gas introduced from the ammonia decomposition reactor, and the other adsorption column is used for adsorptive purification of the gas discharged from the first heat exchanger. The adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor is connected to the burner.

[0010] Further, the adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor is connected to a compressor. A membrane separation device is provided between the adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor and the compressor, and a hydrogen separation metal membrane is provided in the membrane separation device.

[0011] Further, the waste heat recovery unit includes a waste heat power generation unit, a third heat exchanger, and a second lithium battery. The waste heat power generation unit and the third heat exchanger are connected in series. The third heat exchanger is directly connected to the burner. The third heat exchanger is also connected to the first heat exchanger and the second heat exchanger at the same time. The third heat exchanger is then connected to the SOEC electrolyzer. The second lithium battery is electrically connected to the waste heat power generation unit. The waste heat power generation unit is electrically connected to the ammonia decomposition reactor.

[0012] Further, the liquid ammonia tank is connected to a refrigerator, and the third heat exchanger is also connected to an evaporator.

[0013] A hydrogen production process of an efficient hydrogen refueling station system adopting a coupled SOEC hydrogen production device includes the following steps;

[0014] Step 1: Introduce liquid water into the SOEC electrolyzer through the water supply unit. The SOEC electrolyzer electrolyzes the liquid water into hydrogen and oxygen.

[0015] Step 2: Introduce the electrolytically generated oxygen into the burner. Introduce the electrolytically generated hydrogen into the temperature swing adsorption device for adsorptive purification. Evaporate the liquid ammonia in the liquid ammonia tank through the evaporator and introduce it into the ammonia decomposition reactor. Heat the ammonia decomposition reactor using the photovoltaic module. The ammonia decomposition reactor decomposes ammonia into hydrogen and nitrogen. Then introduce the decomposed hydrogen into the temperature swing adsorption device as well.

[0016] Step 3: Introduce the hydrogen electrolytically generated in the temperature swing adsorption device into the hydrogenation unit, and introduce the hydrogen ammonia-decomposed in the temperature swing adsorption device into the burner. The burner mixes and burns the hydrogen and oxygen to generate high-temperature gas.

[0017] Step 4: Transfer the temperature of the high-temperature gas to the liquid water introduced into the SOEC electrolyzer by the water supply unit through the waste heat recovery unit. The waste heat recovery unit uses the high-temperature gas generated by the burner to generate electric energy synchronously.

[0018] Step Five: Transfer the electric energy generated by the waste heat recovery unit to the ammonia decomposition reactor for endothermic decomposition of ammonia; and introduce the decomposition gas after endothermic decomposition of ammonia into the temperature swing adsorption device for adsorption and purification.

[0019] Step Six: Further separate part of the decomposition gas generated by ammonia decomposition in the temperature swing adsorption device to obtain hydrogen; introduce the separated hydrogen into the hydrogenation unit.

[0020] In the high-efficiency hydrogen filling station system coupled with the SOEC hydrogen production device according to the present invention, since the SOEC electrolyzer requires a high temperature of more than 800 °C during operation; during operation, personnel will transfer the heat in the system as much as possible, that is, the heat generated by the burner combustion and the heat of the electrolyzed gas itself, to the liquid water entering the SOEC electrolyzer to meet the operation of the SOEC electrolyzer, realizing the full recovery and utilization of energy during the system operation and improving the system energy utilization rate; and during the operation, combined with the ammonia decomposition hydrogen production reaction, first use the gas after ammonia decomposition, combine the oxygen generated during the electrolysis of water as the fuel of the burner, and at the same time, high-purity hydrogen can be filled; improving the system operation efficiency, especially the hydrogen filling effect in the system; combined with the waste heat recovery unit, generate electricity and store the electric energy by using the heat energy of the burner during the process of filling liquid water into the SOEC electrolyzer, gradually increase the heating of the ammonia decomposition reactor as the reaction proceeds, and then gradually increase the ammonia decomposition efficiency. Finally, combine the membrane separation device to purify the gas after ammonia decomposition, obtain high-purity and large-volume hydrogen and use it for hydrogen filling, improving the energy efficiency and hydrogen filling effect of the hydrogenation process, and reducing the power consumption of the SOEC electrolyzer during the original hydrogen filling process. Description of the Drawings

[0021] In order to more clearly illustrate the specific embodiments of the present invention, the drawings required for the specific embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 This is a high-efficiency hydrogen filling station system coupled with the SOEC hydrogen production device according to the present invention. Detailed Embodiments

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention.

[0024] As Figure 1 shown, a high-efficiency hydrogen production and hydrogen refueling station system for a coupled SOEC hydrogen production device according to the present invention includes a photovoltaic unit 1, an SOEC electrolyzer 2, a burner 3, a water supply unit 4, a waste heat recovery unit 5, an ammonia hydrogen production unit 6, and a hydrogen refueling unit 7;

[0025] The photovoltaic unit 1 is electrically connected to the SOEC electrolyzer 2 and the ammonia hydrogen production unit 6 respectively; the anode outlet of the SOEC electrolyzer 2 communicates with the burner 3;

[0026] The ammonia hydrogen production unit 6 includes a liquid ammonia tank 61 and an ammonia decomposition reactor 62, and the liquid ammonia tank 62 is directly connected to the ammonia decomposition reactor 62; an evaporator 63 is provided between the liquid ammonia tank 62 and the ammonia decomposition reactor 62;

[0027] The hydrogen refueling unit 7 includes a temperature swing adsorption device 71, a compressor 72, a refrigerator 73, and a filling machine 74; the inlet of the temperature swing adsorption device 71 is simultaneously connected to the cathode outlet of the SOEC electrolyzer 2 and the decomposition gas outlet of the ammonia decomposition reactor 62; the outlet of the temperature swing adsorption device 71 is respectively connected to the burner 3 and the compressor 72; the gas discharged from the ammonia decomposition reactor 62 and entering the temperature swing adsorption device 71 is discharged from the temperature swing adsorption device 71 and then enters the burner 3 for combustion; the gas discharged from the SOEC electrolyzer 2 and entering the temperature swing adsorption device 71 is discharged from the temperature swing adsorption device 71 and then enters the compressor 72 for compression; the compressor 72 is sequentially connected to the refrigerator 73 and the filling machine 74;

[0028] The waste heat recovery unit 5 is directly connected to the burner 3, and the water supply unit 4 is connected to the waste heat recovery unit 5; the waste heat recovery unit 5 is connected to the SOEC electrolyzer 2 and is electrically connected to the ammonia decomposition reactor 62; the water in the water supply unit 4 enters the SOEC electrolyzer 2 respectively after passing through the waste heat recovery unit 5.

[0029] At Figure 1Among them, the photovoltaic unit 1 includes a photovoltaic module 11, an inverter 12, and a first lithium battery 13. The photovoltaic module 11 is connected to the inverter 12, and the inverter 12 is electrically connected to the SOEC electrolyzer 2. The first lithium battery 13 is electrically connected to the inverter 12 and the ammonia decomposition reactor 62. The photovoltaic module 11 converts solar energy into electrical energy and outputs it to the inverter 12. The inverter 12 adjusts the voltage of the electrical energy and delivers the electrical energy to the SOEC electrolyzer 2. The surplus electrical energy is stored in the first lithium battery 13, and the electrical energy stored in the first lithium battery 13 can also be used to provide electrical energy for electrolyzing liquid water in the SOEC electrolyzer 2 to ensure the stable operation of the SOEC electrolyzer 2.

[0030] In order to improve the utilization rate of the energy generated during the operation of the SOEC electrolyzer 2 and also accelerate the supply efficiency of liquid water in the system, preferably, the water supply unit 4 includes a water tank 41 and a water pump 42. The water tank 41 is connected to the water pump 42. The anode outlet of the SOEC electrolyzer 2 is connected to the first heat exchanger 8, and the cathode outlet of the SOEC electrolyzer 2 is connected to the second heat exchanger 9. The water pump 42 is further connected to the first heat exchanger 8 and the second heat exchanger 9 respectively. The water pump 42 can pump out the liquid water in the water tank 41 and introduce it into the first heat exchanger 8 and the second heat exchanger 9 respectively. The first heat exchanger 8 can exchange heat between the gas discharged from the anode outlet of the SOEC electrolyzer 2 and the liquid water introduced from the water pump 42. The second heat exchanger 9 can exchange heat between the gas discharged from the cathode outlet of the SOEC electrolyzer 2 and the liquid water introduced from the water pump 42. In the SOEC electrolyzer 2, by electrolyzing the introduced liquid water, a reduction reaction occurs at the anode of the SOEC electrolyzer 2 to generate oxygen, and an oxidation reaction occurs at the cathode of the SOEC electrolyzer 2 to generate hydrogen. The oxygen with a higher temperature generated at the anode of the SOEC electrolyzer 2 enters the second heat exchanger 9 and exchanges heat with the liquid water introduced from the water pump 42 to increase the temperature of the liquid water introduced from the water pump 42. The hydrogen with a higher temperature generated at the cathode of the SOEC electrolyzer 2 enters the first heat exchanger 8 and exchanges heat with the liquid water introduced from the water pump 42 to increase the temperature of the liquid water introduced from the water pump 42 and achieve cooling of the gas after electrolysis in the SOEC electrolyzer 2, effectively utilizing the heat generated during the electrolysis process of the SOEC electrolyzer 2 and being better applicable to the subsequent adsorption and purification process.

[0031] Among them, the first heat exchanger 8 is directly connected to the temperature swing adsorption device 71. The cooled hydrogen gas after heat exchange in the first heat exchanger 8 directly enters the temperature swing adsorption device 71 for adsorption and purification. The temperature swing adsorption device 71 can adsorb the water vapor in the hydrogen gas introduced from the first heat exchanger 8. After adsorption, the hydrogen gas is discharged from the temperature swing adsorption device 71 and enters the compressor 72 connected to the temperature swing adsorption device 71 for compression and storage. Specifically, a first buffer tank 75 is provided between the compressor 72 and the temperature swing adsorption device 71. The first buffer tank 75 is used to store the hydrogen gas purified by the temperature swing adsorption device 71 and adjust the pressure of the purified hydrogen gas to make it more conducive to the subsequent compression of the gas by the compressor 72. The compressed gas then enters the second buffer tank 76 for storage again, and then enters the refrigerator 73 connected thereto for gas cooling. The cooled gas then enters the filling machine 74 to complete the filling of hydrogen gas. Since the electrolytic water reaction occurs in the SOEC electrolyzer 2, the generated hydrogen gas has a high purity. After the reaction, the generated hydrogen gas undergoes temperature swing adsorption, buffering, pressurization, and cooling in sequence, realizing the high-purity and stable storage and filling of hydrogen gas.

[0032] The second heat exchanger 9 is connected to the burner 3. The oxygen electrolytically generated by the SOEC electrolyzer 2 and heated in the second heat exchanger 9 directly enters the burner 3 for combustion in the burner 3 after cooling and heat exchange with the liquid water led out from the water pump 42. Additionally, the ammonia decomposition reactor 62 can decompose ammonia into hydrogen and nitrogen, and the generated hydrogen and nitrogen are discharged through the decomposition gas outlet of the ammonia decomposition reactor 62. The decomposition gas outlet of the ammonia decomposition reactor 62 is connected to the temperature swing adsorption device 71. The hydrogen and nitrogen decomposed by the ammonia decomposition reactor 62 can enter the temperature swing adsorption device 71 for purification adsorption to remove the residual ammonia therein. More specifically, the temperature swing adsorption device 71 includes two adsorption columns connected in parallel. An inlet valve is correspondingly provided at the inlet of each adsorption column, and an outlet valve is also correspondingly provided at the outlet of each adsorption column. One adsorption column is used for adsorbing and purifying the mixed gas containing hydrogen and nitrogen introduced from the ammonia decomposition reactor 62, and the other adsorption column is used for adsorbing and purifying the mixed gas of hydrogen and water vapor discharged from the first heat exchanger 8 after heat exchange. The adsorption column in the temperature swing adsorption device 71 for adsorbing the mixed gas of hydrogen and nitrogen is connected to the burner 3. By controlling the inlet valve and outlet valve of this adsorption column, the mixed gas of hydrogen and nitrogen after adsorption is introduced into the burner 3 for combustion. Under the action of the oxygen discharged from the second heat exchanger 9, the burner 3 mixes and burns the hydrogen introduced from the ammonia decomposition reactor 62 after adsorption with oxygen to generate high-temperature water vapor with a relatively high temperature and release a large amount of heat. Similarly, the adsorption column for adsorbing and purifying the mixed gas of hydrogen and water vapor introduced into the first heat exchanger 8 is connected to the first buffer tank 75. By opening the inlet valve and outlet valve of the adsorption column for purifying hydrogen and water vapor, the hydrogen purified by this adsorption column is introduced into the first buffer tank 75, and then is used for filling after being compressed by a compressor and cooled by a refrigerator. By arranging two temperature swing adsorption devices with different adsorption columns in parallel, different components of gas can be purified synchronously, enabling the filling of hydrogen and the generation of heat by the burner combustion to be carried out synchronously, and separating the gas after ammonia decomposition from the highly pure gas generated by electrolyzing water. Heat is generated during the operation of the system while the hydrogen filling is completed, which is beneficial to the operation of subsequent components and improves the comprehensive operation efficiency of the system.

[0033] The waste heat recovery unit 5 includes a waste heat power generation unit 51 and a third heat exchanger 52. The waste heat power generation unit 51 and the third heat exchanger 52 are connected in series. The third heat exchanger 52 is directly connected to the burner 3, and the third heat exchanger 52 is also connected to the first heat exchanger 8 and the second heat exchanger 9 at the same time. The liquid water introduced from the water pump 42 after heat exchange in the first heat exchanger 8 and the liquid water introduced from the water pump 42 after heat exchange in the second heat exchanger 9 both enter the third heat exchanger 52. The third heat exchanger 52 can further transfer the heat of the gas after combustion in the burner 3 to the liquid water introduced from the first heat exchanger 8 and the second heat exchanger 9 to increase the temperature of the liquid water introduced from the first heat exchanger 8 and the second heat exchanger 9 and make it better suitable for electrolysis in the SOEC electrolyzer 2. The third heat exchanger 52 is then connected to the SOEC electrolyzer 2. After heat exchange in the third heat exchanger 52, the liquid water with a higher temperature enters the SOEC electrolyzer 2 for electrolysis reaction, further increasing the temperature of the liquid water in the SOEC electrolyzer 2, improving the electrolysis efficiency of the SOEC electrolyzer 2 and reducing the temperature required for heating the electrolytic liquid water in the system. It improves the energy utilization rate of the system and helps the SOEC electrolyzer 2 quickly electrolyze to produce hydrogen and oxygen. The liquid water after further heat exchange is discharged from the third heat exchanger 52 and enters the SOEC electrolyzer 2, and electrolyzes in the SOEC electrolyzer 2 to produce hydrogen and oxygen respectively. The generated hydrogen and oxygen then enter the first heat exchanger 8 and the second heat exchanger 9 respectively, and this cycle continues.

[0034] More preferably, the waste heat recovery unit 5 further includes a second lithium battery 53. The second lithium battery 53 is electrically connected to the waste heat power generation unit 51. The waste heat power generation unit 51 uses the low-grade waste heat of the flue gas at the outlet of the heat exchanger 3 to generate electricity and stores the electric energy in the second lithium battery 53 to meet the electricity demand of the hydrogen production and hydrogen refueling system, improving the energy efficiency of the hydrogen refueling station. The second lithium battery 53 is also electrically connected to the compressor and the refrigerator to meet the energy demand during the start-up process of the hydrogen refueling station.

[0035] To further improve the energy utilization rate of the system and reduce the energy consumption of the system to improve the system operation efficiency, preferably, the third heat exchanger is connected to the evaporator 63, the evaporator 63 is respectively connected and communicated with the liquid ammonia tank 61 and the ammonia decomposition reactor 62, and the evaporator 63 can heat and evaporate the liquid ammonia in the liquid ammonia tank 61 to form ammonia gas; for the subsequent decomposition of the ammonia decomposition reactor 62; the liquid water after heat exchange discharged from the third heat exchanger can enter the evaporator 63 as the heat source of the evaporator 63, and exchange heat with the liquid ammonia introduced from the liquid ammonia tank 61 to increase the temperature of the ammonia gas entering the ammonia decomposition reactor 62, so as to improve the ammonia decomposition efficiency in the ammonia decomposition reactor 62; the ammonia decomposition reactor 62 is electrically connected to the waste heat power generation unit 51, and the waste heat power generation unit 51 and the inverter 12 can jointly provide a heat source for heating the ammonia decomposition reactor 62 to heat the ammonia gas in the ammonia decomposition reactor 62 and promote the endothermic decomposition of the ammonia gas, so as to improve the effective reuse of the electric energy generated during the operation of the system; wherein, the waste heat power generation unit 51 can convert the heat generated by the combustion of the burner 3 into electric energy and store it. As the burner 3 continuously burns and heat is continuously generated, the electric energy generated and stored in the waste heat power generation unit 51 continuously increases, correspondingly heating the ammonia decomposition reactor 62 continuously, so that the ammonia gas in the ammonia decomposition reactor 62 can continuously increase in temperature and the decomposition efficiency continuously improves, generating more hydrogen and nitrogen mixed gas; increasing the hydrogen production during the system operation; in addition, by connecting the evaporator 63 to the third heat exchanger, increasing the temperature of the ammonia gas entering the ammonia decomposition reactor 62 can also reduce the power generation demand of the photovoltaic module 1 during the ammonia decomposition process and reduce the energy consumption of the system.

[0036] To better utilize the energy during the operation of the system and balance the energy consumption during the operation of each component so that the system can operate stably, more preferably, the liquid ammonia tank 61 is connected to the refrigerator 73. The liquid ammonia in the liquid ammonia tank 61 first enters the refrigerator 73 as the refrigeration source in the refrigerator 73 to improve the cooling effect of hydrogen in the refrigerator 73. After the cooled liquid ammonia is discharged from the refrigerator 73, it enters the evaporator 63 for vaporization and evaporation. Compared with directly introducing the liquid ammonia in the liquid ammonia tank into the evaporator 63, introducing the liquid ammonia in the liquid ammonia tank into the refrigerator 73 for refrigeration and then evaporating can reduce the heat of the liquid water introduced from the third heat exchanger during the evaporation process; enabling the liquid water after heat exchange in the third heat exchanger to be more used for electrolytic hydrogen production in the SOEC electrolyzer 2; thus balancing the energy requirements of each component and enabling each component to operate effectively.

[0037] As the combustion process in the burner 3 continues, the electric energy is continuously stored and generated in the waste heat power generation unit 51, and the internal temperature in the corresponding ammonia decomposition reactor 62 increases, the ammonia decomposition gas entering the temperature swing adsorption device 71 continuously increases; in order to ultimately increase the hydrogen filling amount and reduce the energy consumption of the system, especially the power consumption; preferably, the outlet end of the adsorption column for adsorbing hydrogen and nitrogen in the temperature swing adsorption device 71 is also connected to the compressor 72, and a membrane separation device is arranged between the adsorption column and the compressor 72, and a hydrogen separation metal membrane, such as a palladium membrane, is arranged in the membrane separation device; the membrane separation device is in thermal connection with the third heat exchanger, and the exhaust gas after combustion of the burner 3 after heat exchange with liquid water in the third heat exchanger can heat the membrane separation device to improve the hydrogen separation effect of the membrane separation device; the membrane separation device can separate the hydrogen and nitrogen introduced from the temperature swing adsorption column 71, separate hydrogen from nitrogen through the selective permeability of hydrogen atoms, and the separated hydrogen is introduced into the compressor 72 for compression, and after compression, it is buffered and cooled in sequence, and then hydrogen is filled; in this way, the hydrogen filling amount in the system is increased.

[0038] The present application also discloses a hydrogen production process for an efficient hydrogen filling station system adopting the coupled SOEC hydrogen production device, including the following steps;

[0039] Step 1: Introduce liquid water into the SOEC electrolyzer through the water supply unit; the SOEC electrolyzer electrolyzes the liquid water into hydrogen and oxygen;

[0040] Step 2: Introduce the electrolytically generated oxygen into the burner; introduce the electrolytically generated hydrogen into the temperature swing adsorption device for adsorption and purification; evaporate the liquid ammonia in the liquid ammonia tank through the evaporator 63 and introduce it into the ammonia decomposition reactor, heat the ammonia decomposition reactor by using the photovoltaic module, and the ammonia decomposition reactor decomposes ammonia into hydrogen and nitrogen; then introduce the decomposed hydrogen into the temperature swing adsorption device as well;

[0041] Step 3: Introduce the hydrogen electrolytically generated in the temperature swing adsorption device into the hydrogen filling unit, introduce the hydrogen generated by ammonia decomposition in the temperature swing adsorption device into the burner, and the burner mixes and burns hydrogen and oxygen to generate high-temperature gas;

[0042] Step 4: Transfer the temperature of the high-temperature gas to the liquid water introduced into the SOEC electrolyzer by the water supply unit through the waste heat recovery unit; the waste heat recovery unit synchronously generates electric energy by using the high-temperature gas generated by the burner;

[0043] Step 5: Transfer the electric energy generated by the waste heat recovery unit to the ammonia decomposition reactor for endothermic decomposition of ammonia; and introduce the decomposition gas after endothermic decomposition of ammonia into the temperature swing adsorption device for adsorption and purification;

[0044] Step Six: Further separate some of the decomposed gas generated by ammonia decomposition in the temperature swing adsorption device to obtain hydrogen; introduce the separated hydrogen into the hydrogenation unit.

[0045] Through the above hydrogen production method, in the system startup stage, the PV module is first used to supply power and heat the SOEC electrolyzer and the ammonia decomposition reactor to start the SOEC electrolyzer and the ammonia decomposition reactor respectively; enabling the electrolysis of water reaction and the ammonia decomposition reaction to be started and carried out synchronously, then introducing both the gas generated by the ammonia decomposition reaction and the gas generated by the electrolysis of water reaction into the temperature swing adsorption device for adsorption and extraction. All the gas generated by the electrolysis of water reaction after temperature swing adsorption is introduced into the hydrogenation unit, and at the same time, the mixed gas containing hydrogen after ammonia decomposition is introduced into the burner, realizing the synchronous progress of the effective filling of high-purity hydrogen in the system and the combustion of the burner to generate high-temperature gas, effectively improving the system operation efficiency and the hydrogen production effect of the system by hydrogenation; then using the waste heat recovery unit to first transfer the heat after combustion to the liquid water entering the SOEC electrolyzer to improve the electrolysis efficiency of the SOEC electrolyzer, and at the same time using the heat after combustion to generate and store electric energy; as the gas continues to burn, the electric energy stored in the waste heat recovery unit continuously increases, and the electric energy stored and generated in the waste heat recovery unit is gradually used to provide energy for the decomposition of ammonia in the ammonia decomposition reactor, continuously increasing the heat in the ammonia decomposition reactor, effectively promoting the ammonia decomposition efficiency in the ammonia decomposition reactor. As the ammonia decomposition efficiency increases, a part of the mixed gas of the decomposed gas after ammonia decomposition is then introduced into the membrane separation device for separation and purification of hydrogen to produce hydrogen; gradually reducing the demand for hydrogen production by the SOEC electrolyzer, reducing the energy consumption of hydrogen production by the SOEC electrolyzer, and simultaneously obtaining high-purity and sufficient hydrogen.

[0046] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. An efficient hydrogen production and hydrogen refueling station system coupled with an SOEC hydrogen production device, comprising a photovoltaic unit, an SOEC electrolyzer, a burner, a water supply unit, a waste heat recovery unit, an ammonia hydrogen production unit, and a hydrogen refueling unit; characterized in that: The photovoltaic unit is electrically connected to the SOEC electrolyzer and the ammonia hydrogen production unit respectively; the anode outlet of the SOEC electrolyzer communicates with the burner; The ammonia hydrogen production unit includes a liquid ammonia tank and an ammonia decomposition reactor, and the liquid ammonia tank is directly connected to the ammonia decomposition reactor; an evaporator is provided between the liquid ammonia tank and the ammonia decomposition reactor; The hydrogen refueling unit includes a temperature swing adsorption device, a compressor, a refrigerator, and a filling machine; the inlet of the temperature swing adsorption device is simultaneously connected to the cathode outlet of the SOEC electrolyzer and the decomposition gas outlet of the ammonia decomposition reactor; the outlet of the temperature swing adsorption device is respectively connected to the burner and the compressor; the gas discharged from the ammonia decomposition reactor and entering the temperature swing adsorption device is discharged from the temperature swing adsorption device and then enters the burner for combustion; the gas discharged from the SOEC electrolyzer and entering the temperature swing adsorption device is discharged from the temperature swing adsorption device and then enters the compressor for compression; the compressor is sequentially connected to the refrigerator and the filling machine; The waste heat recovery unit is directly connected to the burner, and the water supply unit is connected to the waste heat recovery unit; the waste heat recovery unit is connected to the SOEC electrolyzer and is electrically connected to the ammonia decomposition reactor; the water in the water supply unit enters the SOEC electrolyzer respectively after passing through the waste heat recovery unit.

2. The high-efficiency hydrogen refueling station system for a coupled SOEC hydrogen production device according to claim 1, wherein: The photovoltaic unit includes a photovoltaic module, an inverter, and a first lithium battery, the photovoltaic module is connected to the inverter, and the inverter is electrically connected to the SOEC electrolyzer and the ammonia decomposition reactor; the first lithium battery is electrically connected to the inverter.

3. The high-efficiency hydrogen refueling station system for coupling an SOEC hydrogen production device according to claim 1, wherein: It further includes a first heat exchanger and a second heat exchanger, the anode outlet of the SOEC electrolyzer is connected to the first heat exchanger, and the cathode outlet of the SOEC electrolyzer and the second heat exchanger are connected; the water supply unit includes a water tank and a water pump, the water tank and the water pump are directly connected, and the water pump is respectively connected to the first heat exchanger and the second heat exchanger; the first heat exchanger is also directly connected to the temperature swing adsorption device, and the second heat exchanger is also directly connected to the burner.

4. The high-efficiency hydrogen refueling station system for coupling an SOEC hydrogen production device according to claim 1, characterized in that: The temperature swing adsorption device is connected in series with the compressor, the compressor is connected in series with the refrigerator, and the refrigerator is connected in series with the filling machine; a first buffer tank is provided between the temperature swing adsorption device and the compressor, and a second buffer tank is provided between the compressor and the refrigerator.

5. The high-efficiency hydrogen refueling station system for a coupled SOEC hydrogen production device according to claim 3, wherein: The temperature swing adsorption device includes two adsorption columns connected in parallel to each other. An inlet valve is correspondingly provided at the inlet of each adsorption column, and an outlet valve is also correspondingly provided at the outlet of each adsorption column. One of the adsorption columns is used for adsorptive purification of the gas introduced from the ammonia decomposition reactor, and the other adsorption column is used for adsorptive purification of the gas discharged from the first heat exchanger. The adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor is connected to the burner.

6. The high-efficiency hydrogen refueling station system for a coupled SOEC hydrogen production device according to claim 5, characterized in that: The adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor is connected to the compressor. A membrane separation device is provided between the adsorption column in the temperature swing adsorption device for adsorbing the gas introduced from the ammonia decomposition reactor and the compressor. A hydrogen separation metal membrane is provided in the membrane separation device.

7. The high-efficiency hydrogen refueling station system for a coupled SOEC hydrogen production device according to claim 3, wherein: The waste heat recovery unit includes a waste heat generating set, a third heat exchanger, and a second lithium battery. The waste heat generating set and the third heat exchanger are connected in series. The third heat exchanger is directly connected to the burner. The third heat exchanger is also connected to the first heat exchanger and the second heat exchanger at the same time. The third heat exchanger is further connected to the SOEC electrolyzer. The second lithium battery is electrically connected to the waste heat generating set. The waste heat generating set is electrically connected to the ammonia decomposition reactor.

8. The high-efficiency hydrogen refueling station system for coupling an SOEC hydrogen production device according to claim 7, characterized in that: The liquid ammonia tank is connected to the refrigerator. The third heat exchanger is also connected to the evaporator.

9. A hydrogen production process for an efficient hydrogen refueling station system using the coupled SOEC hydrogen production device according to any one of claims 1 to 8, characterized in that: It includes the following steps; Step 1: Introduce liquid water into the SOEC electrolyzer through the water supply unit; The SOEC electrolyzer electrolyzes the liquid water into hydrogen and oxygen; Step 2: Introduce the electrolytically generated oxygen into the burner; introduce the electrolytically generated hydrogen into the temperature swing adsorption device for adsorptive purification; evaporate the liquid ammonia in the liquid ammonia tank through the evaporator and introduce it into the ammonia decomposition reactor, and heat the ammonia decomposition reactor by using the photovoltaic module. The ammonia decomposition reactor decomposes ammonia into hydrogen and nitrogen; then introduce the decomposed hydrogen into the temperature swing adsorption device as well. Step 3: Introduce the hydrogen electrolytically generated in the temperature swing adsorption device into the hydrogenation unit, introduce the hydrogen ammonia-decomposed in the temperature swing adsorption device into the burner, and the burner mixes and burns the hydrogen and oxygen to generate high-temperature gas; Step 4: Transfer the temperature of the high-temperature gas to the liquid water introduced into the SOEC electrolyzer by the water supply unit through the waste heat recovery unit; the waste heat recovery unit synchronously generates electric energy by using the high-temperature gas generated by the burner. Step 5: Transfer the electric energy generated by the waste heat recovery unit to the ammonia decomposition reactor for endothermic decomposition of ammonia; and introduce the decomposed gas after the endothermic decomposition of ammonia into the temperature swing adsorption device for adsorptive purification; Step 6: Further separate a part of the decomposed gas generated by ammonia decomposition in the temperature swing adsorption device to obtain hydrogen; Introduce the separated hydrogen into the hydrogenation unit.

Images