Isolated network green power-green hydrogen-green ammonia three-flexible coupling integrated system and operation method

Abstract

The invention discloses an isolated network green power-green hydrogen-green ammonia three-flexible coupling integrated system and an operation method. The system comprises a wind-light storage flexible power generation system, a renewable energy flexible water electrolysis hydrogen production system and a flexible low-temperature low-pressure ammonia synthesis system. The wind and light storage flexible power generation system is used for carrying out green energy power generation through wind power generation equipment and photovoltaic power generation equipment, and carrying out flexible adjustment on the output power generation amount according to a wind power and photovoltaic output curve coupled by electric energy storage equipment; the renewable energy flexible water electrolysis hydrogen production system is used for flexibly adjusting the hydrogen output quantity by starting and stopping the number of hydrogen production electrolytic cells in the hydrogen electrolysis hydrogen production device and the hydrogen energy storage equipment; the flexible low-temperature and low-pressure ammonia synthesis system is used for automatically reducing or increasing the load of the ammonia reactor and generating green ammonia according to the hydrogen output quantity of the renewable energy flexible electrolytic water hydrogen production system and the nitrogen output quantity of the air separation equipment. The problems that a stable power supply is needed for traditional ammonia hydrogen production and flexible production cannot be achieved due to the fact that traditional ammonia synthesis is limited by the narrow load application range are solved.

Description

Technical Field

[0001] The present invention relates to the field of energy and chemical technology, and in particular to an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system and an operation method. Background Art

[0002] my country is the country with the largest production of synthetic ammonia in the world, with an annual output of about 56 million tons, but most of it uses coal as raw material. The key to developing green ammonia synthesis technology with renewable energy power such as wind and light is the flexible synthesis ammonia technology based on low-temperature and low-pressure synthesis ammonia catalyst. China Energy Construction, State Power Investment Corporation, State Energy Group, Huadian, Huaneng, Three Gorges, Shenzhen Energy, Baofeng, Shuimu Mingtuo, and Envision have successively laid out about 50 green ammonia synthesis projects with a layout capacity of about 10 million tons, but most of them are still based on traditional high-temperature and high-pressure iron-based catalysts, making it difficult to develop flexible synthesis ammonia processes with variable working conditions and loads, and unable to effectively consume wind and solar renewable energy power on site. Therefore, how to simultaneously balance the contradiction between the random fluctuation of green electricity and the long-term stable operation of the synthesis ammonia unit, and propose an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system and operation method, which has important theoretical value and practical significance for giving full play to the advantages of the off-grid green electricity hydrogen-ammonia alcohol integrated system (that is, the old system corresponding to the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system). Summary of the invention

[0003] The present invention provides an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system and an operation method to solve the technical problems mentioned in the background technology.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] The present invention provides an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, comprising:

[0006] The wind, solar and storage flexible power generation system is used to generate green energy through wind power generation equipment and photovoltaic power generation equipment, and flexibly adjust the output power generation according to the coupled wind power and photovoltaic output curves of the energy storage equipment;

[0007] The renewable energy flexible water electrolysis hydrogen production system is used to electrolyze the electricity transmitted by the wind, solar and energy storage flexible power generation system to obtain hydrogen and oxygen, and flexibly adjust the output of hydrogen by starting and stopping the number of hydrogen production electrolyzers in the electrolysis hydrogen production device and the hydrogen energy storage equipment;

[0008] The flexible low-temperature and low-pressure ammonia synthesis system is used to automatically reduce or increase the ammonia reactor load and generate green ammonia according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the ammonia output of the air separation equipment.

[0009] Furthermore, the relationship between the electric energy storage device coupled wind power and photovoltaic output curves is as follows:

[0010] P out i,j =Q W ·k W i,j +Q PV ·k PV i,j +ξ ES i,j Q ES ·k ES i,j

[0011] Where: P out i,j Q is the flexible and adjustable power output by the energy storage after coupling the wind power and photovoltaic output curves at the i-th hour of the j-th day, W is the wind power scale, k W i,j is the wind power output coefficient at the i-th hour on the j-th day, Q PV is the photovoltaic scale, k PV i,j is the photovoltaic output coefficient of the i-th hour on the j-th day, ξ ES i,j is the charge and discharge state of the energy storage at the i-th hour on the j-th day, Q ES is the scale of electric energy storage, k ES i,j is the energy storage charging and discharging power coefficient at the i-th hour on the j-th day.

[0012] Furthermore, the wind-solar-storage flexible power generation system includes photovoltaic power generation equipment, wind power generation equipment and electric energy storage equipment, and the output ends of the photovoltaic power generation equipment and the wind power generation equipment are electrically connected to the input end of the electric energy storage equipment in a parallel connection manner;

[0013] The renewable energy flexible water electrolysis hydrogen production system comprises an electrolysis hydrogen production device and a hydrogen energy storage device, wherein the output ends of the photovoltaic power generation device, the wind power generation device and the electric energy storage device are directly electrically connected to the input end of the electrolysis hydrogen production device, and the output end of the electrolysis hydrogen production device is connected to the hydrogen energy storage device;

[0014] The flexible low-temperature and low-pressure ammonia synthesis system includes an ammonia synthesis tower, an air separation device and an ammonia energy storage device, wherein the output ends of the electrolytic hydrogen production device, the hydrogen energy storage device and the air separation device are directly connected to the input end of the ammonia synthesis tower, and the output end of the ammonia synthesis tower is respectively connected to the input ends of the ammonia energy storage device and other external equipment.

[0015] Furthermore, the electrical energy storage device is selected from one or a combination of electrochemical energy storage devices, pumped storage devices, compressed air energy storage devices or gravity energy storage devices.

[0016] Furthermore, the synthetic ammonia tower includes a heat exchanger, an ammonia reactor with a built-in ruthenium-based catalyst, a waste heat recovery device, a cooling and separation device, and a circulation machine;

[0017] The output ends of the renewable energy flexible water electrolysis hydrogen production system, the air separation equipment and the circulation machine are respectively connected to the input ends of the heat exchanger, one of the output ends of the heat exchanger is connected to the output end of the ammonia reactor, the output end of the ammonia reactor is connected to the input end of the cooling and separation equipment through the waste heat recovery equipment and the other output end of the heat exchanger, and the output end of the cooling and separation equipment is connected to the input end of the circulation machine.

[0018] Furthermore, the ammonia reactor is used to synthesize green ammonia under the catalysis of a built-in ruthenium-based catalyst after preheating and mixing the hydrogen output from the output end of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output from the output end of the air separation equipment through a heat exchanger, and then produce liquid ammonia through a cooling and separation device;

[0019] The waste heat recovery device is used to recover the heat generated by the ammonia reactor and output it to the heat exchanger;

[0020] The circulator is used to circulate and output the remaining hydrogen and nitrogen after the cooling and separation equipment produces liquid ammonia, and then mix them with fresh hydrogen and nitrogen and input them to the heat exchanger for preheating.

[0021] Another aspect of the present invention provides an operation method of an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, comprising the following steps:

[0022] S1. Turn on the wind-solar-storage flexible power generation system. The photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity. The power generation output to the renewable energy flexible water electrolysis hydrogen production system is flexibly adjusted by using the electric energy storage equipment and according to the electric energy storage coupling wind power and photovoltaic output curve;

[0023] Flexible regulation mainly refers to reducing the system output when the system output exceeds the maximum threshold; increasing the system output when the system output is lower than the minimum threshold;

[0024] S2. The electrolysis hydrogen production device in the renewable energy flexible electrolysis water hydrogen production system uses the electricity transmitted by the wind, solar and energy storage flexible power generation system to electrolyze water into hydrogen and oxygen, and flexibly adjusts the output of hydrogen to the flexible low-temperature and low-pressure synthetic ammonia system by starting and stopping the number of hydrogen production electrolytic cells in the electrolysis hydrogen production device and the hydrogen energy storage equipment;

[0025] S3. The air separation equipment decomposes the air into oxygen and nitrogen. Then the flexible low-temperature and low-pressure ammonia synthesis system automatically reduces or increases the load of the ammonia reactor according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment, and generates green ammonia.

[0026] S4, cycle S1 to S3 until the green electricity-green hydrogen-green ammonia three-flexible coupled integrated system is shut down.

[0027] Furthermore, the S1 specifically includes the following steps:

[0028] S11. Turn on the wind-solar-storage flexible power generation system, and the photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity and supply power to the renewable energy flexible water electrolysis hydrogen production system;

[0029] S12. Compare and judge the total power generation of the photovoltaic power generation equipment and the wind power generation equipment with the power consumption of the renewable energy flexible water electrolysis hydrogen production system based on the electric energy storage device coupled wind power and photovoltaic output curve;

[0030] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is greater than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the energy storage device on the wind-solar-storage flexible power generation system will store the excess power;

[0031] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is equal to the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the total power generation of the photovoltaic power generation equipment and the wind power generation equipment will all be used to supply power to the renewable energy flexible water electrolysis hydrogen production system;

[0032] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is less than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, then on the basis of using the total power generation of the photovoltaic power generation equipment and the wind power generation equipment to supply power to the renewable energy flexible water electrolysis hydrogen production system, the electric energy storage equipment on the wind, solar and storage flexible power generation system is turned on, and the electric energy storage equipment is used to supply power to the renewable energy flexible water electrolysis hydrogen production system.

[0033] Furthermore, the S2 specifically includes the following steps:

[0034] S21. The wind, solar and energy storage flexible power generation system supplies power to the electrolysis hydrogen production device on the renewable energy flexible water electrolysis hydrogen production system. The electrolysis hydrogen production device electrolyzes water into hydrogen and oxygen at a pressure of 1.6 to 3.2 MPa and a temperature of 80 to 90°C, and then transports the hydrogen to the hydrogen energy storage device or the synthetic ammonia tower.

[0035] S22, according to the current gas storage capacity of the hydrogen energy storage equipment, the load status of the synthetic ammonia tower, and the power generation of the wind, solar and storage flexible power generation system, determine the start and stop number of multiple hydrogen production electrolyzers in the electrolytic hydrogen production device and the gas supply status of the hydrogen energy storage equipment, so as to achieve flexible regulation of the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system;

[0036] When the hydrogen storage capacity of the hydrogen energy storage device is greater than the preset maximum value and the synthetic ammonia tower is running at full load, several hydrogen production electrolyzers in the electrolytic hydrogen production device stop working or reduce power, and then the excess power generated by the photovoltaic power generation equipment and wind power generation equipment is stored in the electric energy storage device;

[0037] When the power generation of the wind-solar-storage flexible power generation system is less than the power consumption of multiple hydrogen production electrolyzers, the hydrogen stored in the hydrogen energy storage device is consumed first;

[0038] When the hydrogen stored in the hydrogen energy storage device is less than a preset minimum value, the number of hydrogen production electrolyzers opened is increased and the ammonia reactor load is reduced.

[0039] Furthermore, the S3 specifically includes the following steps:

[0040] S31, the air separation equipment decomposes air into nitrogen and oxygen at a pressure of 0.7-0.8 MPa and a temperature of 20-40°C, and then the nitrogen and the hydrogen delivered by the renewable energy flexible water electrolysis hydrogen production system are input into the ammonia reactor through a heat exchanger;

[0041] S32. Under the conditions of a hydrogen-nitrogen ratio control range of 1.0 to 3.5, an inlet hydrogen-nitrogen ratio of ≤2, a reaction pressure of ≤6.5MPa, and an outlet temperature of ≤390°C, the ammonia reactor synthesizes green ammonia from nitrogen and oxygen under the catalysis of a ruthenium-based catalyst, with an outlet ammonia concentration of ≥16%, and then passes through a cooling and separation device to produce liquid ammonia. At the same time, the heat generated by the ammonia reactor is transmitted to a heat exchanger through a waste heat recovery device; the circulating machine circulates and outputs the remaining hydrogen and nitrogen after the cooling and separation device produces liquid ammonia, and then mixes them with fresh hydrogen and nitrogen and inputs them to the heat exchanger for preheating;

[0042] S33, cycle S31 and S32, and during the cycle, automatically reduce or increase the ammonia reactor load according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment. The ammonia reactor load control range is 30% to 150% until the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system is shut down.

[0043] Beneficial effects of the present invention:

[0044] The present invention discloses an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, wherein the isolated grid refers to an off-grid type, that is, the present invention can generate green ammonia without being connected to a large power grid, and is not restricted by grid access, power supply belt, access indicators, etc., without relying on an external power supply, and will not affect the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system due to consumption problems;

[0045] In addition, the present invention breaks through the problem that traditional hydrogen and ammonia production requires a stable power supply and traditional synthetic ammonia is restricted by a narrow load adaptation range and cannot achieve flexible production. It can use multiple energy storage facilities such as electric energy storage, hydrogen energy storage, and ammonia energy storage to adjust the peak and fill the valley, effectively reducing the impact of high-frequency and wide-amplitude fluctuations generated in wind power generation and photovoltaic power generation on the green hydrogen and green ammonia production process, and can meet the production load requirements of 30% to 110% for hydrogen production electrolyzers. And the use of an ammonia reactor with a built-in ruthenium-based catalyst can achieve the flexible adjustment requirements of the synthetic ammonia tower within the production load range of 30% to 150%. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a working principle diagram of the overall green electricity-green hydrogen-green ammonia three-flexible coupling integrated system in the present invention;

[0047] Figure 2 This is a diagram of the working principles of various devices in the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are provided in the drawings. However, the present invention can be implemented in many other different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0049] It should also be noted that, in the embodiments of the present application, the same figure mark is used to represent the same component or the same part. For the same parts in the embodiments of the present application, the figure may only mark one of the parts or components as an example. It should be understood that the figure mark also applies to other identical parts or components.

[0050] Reference Figure 1 The embodiment of the present application provides an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, including:

[0051] The wind, solar and storage flexible power generation system is used to generate green energy through wind power generation equipment and photovoltaic power generation equipment, and flexibly adjust the output power generation according to the coupled wind power and photovoltaic output curves of the energy storage equipment;

[0052] The renewable energy flexible water electrolysis hydrogen production system is used to electrolyze the electricity transmitted by the wind, solar and energy storage flexible power generation system to obtain hydrogen and oxygen, and flexibly adjust the output of hydrogen by starting and stopping the number of hydrogen production electrolyzers in the electrolysis hydrogen production device and the hydrogen energy storage equipment;

[0053] The flexible low-temperature and low-pressure ammonia synthesis system is used to automatically reduce or increase the ammonia reactor load and generate green ammonia according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation plant.

[0054] In some embodiments, the relationship between the electric energy storage device coupled wind power and photovoltaic output curves is as follows:

[0055] P out i,j =Q W ·k W i,j +Q PV ·k PV i,j +ξ ES i,j Q ES ·k ES i,j

[0056] Where: P out i,j Q is the flexible and adjustable power output by the energy storage after coupling the wind power and photovoltaic output curves at the i-th hour of the j-th day, W is the wind power scale, k W i,j is the wind power output coefficient at the i-th hour on the j-th day, Q PV is the photovoltaic scale, k PV i,j is the photovoltaic output coefficient of the i-th hour on the j-th day, ξ ES i,j is the charge and discharge state of the energy storage at the i-th hour on the j-th day, Q ES is the scale of electric energy storage, k ES i,j is the energy storage charging and discharging power coefficient at the i-th hour on the j-th day.

[0057] In some embodiments, reference Figure 2 The wind-solar-storage flexible power generation system includes a photovoltaic power generation device, a wind power generation device and an electric energy storage device. The output ends of the photovoltaic power generation device and the wind power generation device are electrically connected to the input end of the electric energy storage device in a parallel connection mode; preferably, the power generation power of the wind power generation device is 55MW, and the power generation power of the photovoltaic power generation device is 11MW;

[0058] The renewable energy flexible water electrolysis hydrogen production system includes an electrolytic hydrogen production device and a hydrogen energy storage device. The output ends of the photovoltaic power generation equipment, the wind power generation equipment and the electrical energy storage device are directly electrically connected to the input end of the electrolytic hydrogen production device, and the output end of the electrolytic hydrogen production device is connected to the hydrogen energy storage device. Preferably, the electrolytic hydrogen production device includes 8 hydrogen production electrolyzers, and the input power of each hydrogen production electrolyzer is 5MW; the hydrogen storage capacity of the hydrogen energy storage device is 8 tons.

[0059] The flexible low-temperature and low-pressure ammonia synthesis system includes an ammonia synthesis tower, an air separation device and an ammonia energy storage device, wherein the output ends of the electrolytic hydrogen production device, the hydrogen energy storage device and the air separation device are directly connected to the input end of the ammonia synthesis tower, and the output end of the ammonia synthesis tower is respectively connected to the input ends of the ammonia energy storage device and other external equipment.

[0060] In some embodiments, the electrical energy storage device is selected from one or a combination of electrochemical energy storage devices, pumped storage devices, compressed air energy storage devices, or gravity energy storage devices. Preferably, the charge and discharge power of the electrochemical energy storage is 13MW, and the capacity of the electrochemical energy storage is 13MWh.

[0061] In some embodiments, the synthetic ammonia tower includes a heat exchanger, an ammonia reactor with a built-in ruthenium-based catalyst, a waste heat recovery device, a cooling and separation device, and a circulation machine;

[0062] The output ends of the renewable energy flexible water electrolysis hydrogen production system, the air separation equipment and the circulation machine are respectively connected to the input end of the heat exchanger, one of the output ends of the heat exchanger is connected to the output end of the ammonia reactor, the output end of the ammonia reactor is respectively connected to the input end of the cooling and separation equipment through the waste heat recovery equipment and the other output end of the heat exchanger, and the output end of the cooling and separation equipment is connected to the input end of the circulation machine. Preferably, the annual output of the ammonia reactor is 30,000 tons / year.

[0063] In some embodiments, the ammonia reactor is used to synthesize green ammonia under the catalysis of a built-in ruthenium-based catalyst after preheating and mixing the hydrogen output from the output end of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output from the output end of the air separation equipment through a heat exchanger, and then produce liquid ammonia through a cooling and separation device;

[0064] The waste heat recovery device is used to recover the heat generated by the ammonia reactor and output it to the heat exchanger;

[0065] The circulator is used to circulate and output the remaining hydrogen and nitrogen after the cooling and separation equipment produces liquid ammonia, and then mix them with fresh hydrogen and nitrogen and input them to the heat exchanger for preheating.

[0066] In some embodiments, the flexible low-temperature and low-pressure synthetic ammonia system further includes an ammonia energy storage device, the input end of the ammonia energy storage device is connected to the output end of the synthetic ammonia tower, and the ammonia energy storage device is used to store liquid nitrogen.

[0067] The present invention discloses an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, wherein the isolated grid refers to an off-grid type, that is, the present invention can generate green ammonia without being connected to a large power grid, and is not restricted by grid access, power supply belt, access indicators, etc., without relying on an external power supply, and will not affect the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system due to consumption problems;

[0068] In addition, the present invention breaks through the problem that traditional hydrogen and ammonia production requires a stable power supply and traditional synthetic ammonia is restricted by a narrow load adaptation range and cannot achieve flexible production. It can use a variety of energy storage facilities such as electric energy storage, hydrogen energy storage, and ammonia energy storage to adjust the peak and fill the valley, effectively reducing the high-frequency and wide-amplitude fluctuations generated in wind power generation and photovoltaic power generation. The impact on the green hydrogen and green ammonia production process can meet the production load requirements of 30% to 110% for hydrogen production electrolyzers. And the use of an ammonia reactor with a built-in ruthenium-based catalyst can achieve the flexible adjustment requirements of the synthetic ammonia tower within the production load range of 30% to 150%. .

[0069] On the other hand, the present invention also provides an operation method of an isolated green power-green hydrogen-green ammonia three-flexible coupling integrated system, comprising the following steps:

[0070] S1. Turn on the wind-solar-storage flexible power generation system. The photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity. The power generation output (i.e., actual power generation) to the renewable energy flexible water electrolysis hydrogen production system is flexibly adjusted by using the electric energy storage equipment and according to the electric energy storage coupling wind power and photovoltaic output curves; so as to realize the flexible adjustment of the wind-solar-storage flexible power generation system to the actual power generation;

[0071] Flexible regulation mainly refers to reducing the system output when the system output exceeds the maximum threshold; increasing the system output when the system output is lower than the minimum threshold;

[0072] S2. The electrolysis hydrogen production device in the renewable energy flexible electrolysis water hydrogen production system uses the electricity transmitted by the wind, solar and energy storage flexible power generation system to electrolyze water into hydrogen and oxygen, and flexibly adjusts the output of hydrogen to the flexible low-temperature and low-pressure ammonia synthesis system by starting and stopping the number of hydrogen production electrolytic cells in the electrolysis hydrogen production device and the hydrogen energy storage device; so as to realize the flexible regulation of hydrogen output by the renewable energy flexible electrolysis water hydrogen production system;

[0073] S3. The air separation equipment decomposes the air into oxygen and nitrogen. Then the flexible low-temperature and low-pressure ammonia synthesis system automatically reduces or increases the load of the ammonia reactor and generates green ammonia according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment, thereby achieving the goal of flexible regulation;

[0074] S4, cycle S1 to S3 until the green electricity-green hydrogen-green ammonia three-flexible coupled integrated system is shut down.

[0075] In some embodiments, the S1 specifically includes the following steps:

[0076] S11, start the wind-solar-storage flexible power generation system, and the photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity, a part of the electricity is stored in the electric energy storage equipment, and the other part of the electricity is used to supply power to the renewable energy flexible water electrolysis hydrogen production system;

[0077] S12. Compare and judge the total power generation of the photovoltaic power generation equipment and the wind power generation equipment with the power consumption of the renewable energy flexible water electrolysis hydrogen production system based on the electric energy storage device coupled wind power and photovoltaic output curve;

[0078] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is greater than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the energy storage device on the wind-solar-storage flexible power generation system will store the excess power;

[0079] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is equal to the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the total power generation of the photovoltaic power generation equipment and the wind power generation equipment will all be used to supply power to the renewable energy flexible water electrolysis hydrogen production system;

[0080] If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is less than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, then on the basis of using the total power generation of the photovoltaic power generation equipment and the wind power generation equipment to supply power to the renewable energy flexible water electrolysis hydrogen production system, the electric energy storage equipment on the wind, solar and storage flexible power generation system is turned on, and the electric energy storage equipment is used to supply power to the renewable energy flexible water electrolysis hydrogen production system.

[0081] In some embodiments, S2 specifically includes the following steps:

[0082] S21. The wind, solar and energy storage flexible power generation system supplies power to the electrolysis hydrogen production device on the renewable energy flexible water electrolysis hydrogen production system. The electrolysis hydrogen production device electrolyzes water into hydrogen and oxygen at a pressure of 1.6 to 3.2 MPa and a temperature of 80 to 90°C, and then transports the hydrogen to the hydrogen energy storage device or the synthetic ammonia tower.

[0083] S22, according to the current gas storage capacity of the hydrogen energy storage equipment, the load status of the synthetic ammonia tower, and the power generation of the wind, solar and storage flexible power generation system, determine the start and stop number of multiple hydrogen production electrolyzers in the electrolytic hydrogen production device and the gas supply status of the hydrogen energy storage equipment, so as to achieve flexible regulation of the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system;

[0084] When the hydrogen storage capacity of the hydrogen energy storage device is greater than the preset maximum value and the synthetic ammonia tower is running at full load, several hydrogen production electrolyzers in the electrolytic hydrogen production device stop working or reduce power, and then the excess power generated by the photovoltaic power generation equipment and wind power generation equipment is stored in the electric energy storage device;

[0085] When the power generation of the wind-solar-storage flexible power generation system is less than the power consumption of multiple hydrogen production electrolyzers, the hydrogen stored in the hydrogen energy storage device is consumed first;

[0086] When the hydrogen stored in the hydrogen energy storage device is less than a preset minimum value, the number of hydrogen production electrolyzers opened is increased and the ammonia reactor load is reduced.

[0087] In some embodiments, S3 specifically includes the following steps:

[0088] S31, the air separation equipment decomposes air into nitrogen and oxygen at a pressure of 0.7-0.8 MPa and a temperature of 20-40°C, and then the nitrogen and the hydrogen delivered by the renewable energy flexible water electrolysis hydrogen production system are input into the ammonia reactor through a heat exchanger;

[0089] S32. Under the conditions of a hydrogen-nitrogen ratio control range of 1.0 to 3.5, an inlet hydrogen-nitrogen ratio of ≤2, a reaction pressure of ≤6.5MPa, and an outlet temperature of ≤390°C, the ammonia reactor synthesizes green ammonia from nitrogen and oxygen under the catalysis of a ruthenium-based catalyst, with an outlet ammonia concentration of ≥16%, and then passes through a cooling and separation device to produce liquid ammonia. At the same time, the heat generated by the ammonia reactor is transmitted to a heat exchanger through a waste heat recovery device; the circulating machine circulates and outputs the remaining hydrogen and nitrogen after the cooling and separation device produces liquid ammonia, and then mixes them with fresh hydrogen and nitrogen and inputs them to the heat exchanger for preheating;

[0090] S33, cycle S31 and S32, and during the cycle, automatically reduce or increase the ammonia reactor load according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment. The ammonia reactor load control range is 30% to 150% until the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system is shut down.

[0091] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered within the protection scope of the present invention. In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, characterized in that: include: The wind, solar and storage flexible power generation system is used to generate green energy through wind power generation equipment and photovoltaic power generation equipment, and flexibly adjust the output power generation according to the coupled wind power and photovoltaic output curves of the energy storage equipment; The renewable energy flexible water electrolysis hydrogen production system is used to electrolyze the electricity transmitted by the wind, solar and energy storage flexible power generation system to obtain hydrogen and oxygen, and flexibly adjust the output of hydrogen by starting and stopping the number of hydrogen production electrolyzers in the electrolysis hydrogen production device and the hydrogen energy storage equipment; The flexible low-temperature and low-pressure ammonia synthesis system is used to automatically reduce or increase the ammonia reactor load and generate green ammonia according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation plant.

2. The isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system according to claim 1 is characterized in that: The relationship between the electric energy storage device coupled wind power and photovoltaic output curves is as follows: P out i,j =Q W ·k W i,j +Q PV ·k PV i,j +ξ ES i,j ·Q ES ·k ES i,j Where: P out i,j Q is the flexible and adjustable power output by the energy storage after coupling the wind power and photovoltaic output curves at the i-th hour of the j-th day, W is the wind power scale, k W i,j is the wind power output coefficient at the i-th hour on the j-th day, Q PV is the photovoltaic scale, k PV i,j is the photovoltaic output coefficient of the i-th hour on the j-th day, ξ ES i,j is the charge and discharge state of the energy storage at the i-th hour on the j-th day, Q ES is the scale of electric energy storage, k ES i,j is the energy storage charging and discharging power coefficient at the i-th hour on the j-th day.

3. The isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system according to claim 1 is characterized in that: The wind-solar-storage flexible power generation system comprises a photovoltaic power generation device, a wind power generation device and an electric energy storage device, wherein the output ends of the photovoltaic power generation device and the wind power generation device are electrically connected to the input end of the electric energy storage device in a parallel connection manner; The renewable energy flexible water electrolysis hydrogen production system comprises an electrolysis hydrogen production device and a hydrogen energy storage device, wherein the output ends of the photovoltaic power generation device, the wind power generation device and the electric energy storage device are directly electrically connected to the input end of the electrolysis hydrogen production device, and the output end of the electrolysis hydrogen production device is connected to the hydrogen energy storage device; The flexible low-temperature and low-pressure ammonia synthesis system includes an ammonia synthesis tower, an air separation device and an ammonia energy storage device, wherein the output ends of the electrolytic hydrogen production device, the hydrogen energy storage device and the air separation device are directly connected to the input end of the ammonia synthesis tower, and the output end of the ammonia synthesis tower is respectively connected to the input ends of the ammonia energy storage device and other external equipment.

4. The isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system according to claim 3 is characterized in that: The electrical energy storage device is selected from one or a combination of electrochemical energy storage devices, pumped storage devices, compressed air energy storage devices or gravity energy storage devices.

5. The isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system according to claim 3 is characterized in that: The synthetic ammonia tower includes a heat exchanger, an ammonia reactor with a built-in ruthenium-based catalyst, a waste heat recovery device, a cooling and separation device, and a circulation machine; The output ends of the renewable energy flexible water electrolysis hydrogen production system, the air separation equipment and the circulation machine are respectively connected to the input ends of the heat exchanger, one of the output ends of the heat exchanger is connected to the output end of the ammonia reactor, the output end of the ammonia reactor is connected to the input end of the cooling and separation equipment through the waste heat recovery equipment and the other output end of the heat exchanger, and the output end of the cooling and separation equipment is connected to the input end of the circulation machine.

6. The isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system according to claim 5 is characterized in that: The ammonia reactor is used to synthesize green ammonia under the catalysis of a built-in ruthenium-based catalyst after preheating and mixing the hydrogen output from the output end of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output from the output end of the air separation equipment through a heat exchanger, and then produce liquid ammonia through a cooling and separation device; The waste heat recovery device is used to recover the heat generated by the ammonia reactor and output it to the heat exchanger; The circulator is used to circulate and output the remaining hydrogen and nitrogen after the cooling and separation equipment produces liquid ammonia, and then mix them with fresh hydrogen and nitrogen and input them to the heat exchanger for preheating.

7. An operation method of an isolated grid green electricity-green hydrogen-green ammonia three-flexible coupling integrated system, characterized in that: The steps include: S1. Turn on the wind-solar-storage flexible power generation system. The photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity. The power generation output to the renewable energy flexible water electrolysis hydrogen production system is flexibly adjusted by using the electric energy storage equipment and according to the electric energy storage coupling wind power and photovoltaic output curve; S2. The electrolysis hydrogen production device in the renewable energy flexible electrolysis water hydrogen production system uses the electricity transmitted by the wind, solar and energy storage flexible power generation system to electrolyze water into hydrogen and oxygen, and flexibly adjusts the output of hydrogen to the flexible low-temperature and low-pressure synthetic ammonia system by starting and stopping the number of hydrogen production electrolytic cells in the electrolysis hydrogen production device and the hydrogen energy storage equipment; S3. The air separation equipment decomposes the air into oxygen and nitrogen. Then the flexible low-temperature and low-pressure ammonia synthesis system automatically reduces or increases the load of the ammonia reactor according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment, and generates green ammonia. S4, cycle S1 to S3 until the green electricity-green hydrogen-green ammonia three-flexible coupled integrated system is shut down.

8. The operating method according to claim 7, characterized in that: The S1 specifically includes the following steps: S11. Turn on the wind-solar-storage flexible power generation system, and the photovoltaic power generation equipment and wind power generation equipment on the wind-solar-storage flexible power generation system start to generate electricity and supply power to the renewable energy flexible water electrolysis hydrogen production system; S12. Compare and judge the total power generation of the photovoltaic power generation equipment and the wind power generation equipment with the power consumption of the renewable energy flexible water electrolysis hydrogen production system based on the electric energy storage device coupled wind power and photovoltaic output curve; If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is greater than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the energy storage device on the wind-solar-storage flexible power generation system will store the excess power; If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is equal to the power consumption of the renewable energy flexible water electrolysis hydrogen production system, the total power generation of the photovoltaic power generation equipment and the wind power generation equipment will all be used to supply power to the renewable energy flexible water electrolysis hydrogen production system; If the total power generation of the photovoltaic power generation equipment and the wind power generation equipment is less than the power consumption of the renewable energy flexible water electrolysis hydrogen production system, then on the basis of using the total power generation of the photovoltaic power generation equipment and the wind power generation equipment to supply power to the renewable energy flexible water electrolysis hydrogen production system, the electric energy storage equipment on the wind, solar and storage flexible power generation system is turned on, and the electric energy storage equipment is used to supply power to the renewable energy flexible water electrolysis hydrogen production system.

9. The operating method according to claim 7, characterized in that: The S2 specifically includes the following steps: S21. The wind, solar and energy storage flexible power generation system supplies power to the electrolysis hydrogen production device on the renewable energy flexible water electrolysis hydrogen production system. The electrolysis hydrogen production device electrolyzes water into hydrogen and oxygen at a pressure of 1.6 to 3.2 MPa and a temperature of 80 to 90°C, and then transports the hydrogen to the hydrogen energy storage device or the synthetic ammonia tower. S22, according to the current gas storage capacity of the hydrogen energy storage equipment, the load status of the synthetic ammonia tower, and the power generation of the wind, solar and storage flexible power generation system, determine the start and stop number of multiple hydrogen production electrolyzers in the electrolytic hydrogen production device and the gas supply status of the hydrogen energy storage equipment, so as to achieve flexible regulation of the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system; When the hydrogen storage capacity of the hydrogen energy storage device is greater than the preset maximum value and the synthetic ammonia tower is running at full load, several hydrogen production electrolyzers in the electrolytic hydrogen production device stop working or reduce power, and then the excess power generated by the photovoltaic power generation equipment and wind power generation equipment is stored in the electric energy storage device; When the power generation of the wind-solar-storage flexible power generation system is less than the power consumption of multiple hydrogen production electrolyzers, the hydrogen stored in the hydrogen energy storage device is consumed first; When the hydrogen stored in the hydrogen energy storage device is less than a preset minimum value, the number of hydrogen production electrolyzers opened is increased and the ammonia reactor load is reduced.

10. The operating method according to any one of claims 7 to 9, characterized in that: The S3 specifically includes the following steps: S31, the air separation equipment decomposes air into nitrogen and oxygen at a pressure of 0.7-0.8 MPa and a temperature of 20-40°C, and then the nitrogen and the hydrogen delivered by the renewable energy flexible water electrolysis hydrogen production system are input into the ammonia reactor through a heat exchanger; S32. Under the conditions of a hydrogen-nitrogen ratio control range of 1.0 to 3.5, an inlet hydrogen-nitrogen ratio ≤ 2, a reaction pressure ≤ 6.5 MPa, and an outlet temperature ≤ 390°C, the ammonia reactor synthesizes green ammonia from nitrogen and oxygen under the catalysis of a ruthenium-based catalyst, with an outlet ammonia concentration ≥ 16%, and then passes through a cooling and separation device to produce liquid ammonia. At the same time, the heat generated by the ammonia reactor is transmitted to a heat exchanger through a waste heat recovery device; the circulating machine circulates and outputs the remaining hydrogen and nitrogen after the cooling and separation device produces liquid ammonia, and then mixes them with fresh hydrogen and nitrogen and inputs them to the heat exchanger for preheating; S33, cycle S31 and S32, and during the cycle, automatically reduce or increase the ammonia reactor load according to the hydrogen output of the renewable energy flexible water electrolysis hydrogen production system and the nitrogen output of the air separation equipment. The ammonia reactor load control range is 30% to 150% until the green electricity-green hydrogen-green ammonia three-flexible coupling integrated system is shut down.

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