Co-production process system and co-production process method

Abstract

The invention discloses a co-production process system and a co-production process method.The co-production process system is used for providing natural gas and hydrogen, and the co-production process system comprises an in-station process system and an in-station micro-grid capable of supplying power to the in-station process system; the in-station process system comprises a natural gas preparation system and a hydrogen preparation system; the natural gas preparation system is used for gasifying the received liquefied natural gas to obtain natural gas and storing cold energy released in the gasification process; and the hydrogen preparation system is connected with the natural gas preparation system and is used for preparing hydrogen and liquefying, storing and gasifying the prepared hydrogen by utilizing the stored cold energy. By adopting the embodiment of the invention, the coupling of processes such as LNG gasification, cold energy storage and hydrogen preparation, liquefaction, storage and gasification can be realized, the fusion of the normal production of the LNG receiving station and the whole process of hydrogen preparation, storage and transportation is realized, and the comprehensive and deep fusion of an LNG industry chain and a hydrogen energy industry chain can be realized.

Description

Technical Field

[0001] The present application relates to the field of co-production of liquefied natural gas and hydrogen, and in particular to a co-production process system and a co-production process method. Background Art

[0002] With the acceleration of global energy transformation and the improvement of environmental awareness, the market demand for hydrogen energy, as one of the representatives of clean energy, will continue to grow. As an important way to store and transport hydrogen energy, liquid hydrogen has the advantages of high hydrogen storage density, high refueling efficiency, and good safety. With the expansion of liquid hydrogen production scale and the maturity of storage and transportation technology, the production and storage and transportation costs of liquid hydrogen will gradually decrease. According to institutional forecasts, by 2050, the storage and transportation costs of liquid hydrogen are expected to drop by 50% to 8-10 yuan / kg, which will further promote the large-scale application of liquid hydrogen. LNG (Liquefied Natural Gas) is also closely related to the hydrogen industry. The mature system of the LNG industry can be used to help the development of the hydrogen industry chain and achieve a deep integration of the two.

[0003] In recent years, relevant scholars have conducted extensive research on the hydrogen liquefaction process using LNG cold energy. Most of the related technologies simply couple LNG and hydrogen production.

[0004] How to provide a production process that can fully and deeply integrate the LNG industry chain with the hydrogen energy industry chain is an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a co-production process system and a co-production process method.

[0006] In a first aspect, an embodiment of the present application provides a cogeneration process system for providing natural gas and hydrogen, the system comprising: an in-station process system and an in-station microgrid capable of supplying power to the in-station process system; The process systems within the station include natural gas production system and hydrogen production system; The natural gas production system is used to gasify the received liquefied natural gas to obtain natural gas, and store the cold energy released during the gasification process; The hydrogen production system is connected to the natural gas production system, and is used to produce hydrogen, and utilizes the stored cold energy to liquefy, store and gasify the produced hydrogen.

[0007] In an optional embodiment, the in-station microgrid includes an LNG cold energy power generation system, a new energy power generation system, an in-station energy storage system, and a power grid control system; The LNG supply system is connected to the LNG cold energy power generation system through a first LNG transmission pipeline; The LNG cold energy power generation system is connected to the station energy storage system through the station power grid, and is used to generate cold energy using the received liquefied natural gas; The new energy power generation system is connected to the station energy storage system through the station power grid, and is used to generate new energy using the new energy raw materials in the station; The in-station energy storage system is connected to the in-station process system through the in-station power grid, and is used to store the electric energy provided by the LNG cold energy power generation system and the new energy power generation system, and to supply power to the in-station process system 102; The power grid control system is used to control the storage and supply of electric energy in the energy storage system within the station.

[0008] In an optional embodiment, the natural gas production system includes an LNG gasification system and a cold energy storage system; The LNG supply system is connected to the LNG gasification system through a second LNG transmission pipeline; The LNG gasification system is connected to the cold energy storage system through a first refrigerant circulation pipeline and a second refrigerant circulation pipeline.

[0009] In an optional embodiment, the hydrogen production system includes a water electrolysis hydrogen production system, a hydrogen liquefaction system, a liquid hydrogen storage system and a liquid hydrogen gasification system; The water electrolysis hydrogen production system is connected to the hydrogen liquefaction system through a hydrogen transmission pipeline; The cold energy storage system is connected to the hydrogen liquefaction system through the third refrigerant circulation pipeline and the fourth refrigerant circulation pipeline; The hydrogen liquefaction system is connected to the liquid hydrogen storage system through a liquid hydrogen transmission pipeline; The liquid hydrogen storage system is connected through a liquid hydrogen transmission pipeline and a liquid hydrogen gasification system.

[0010] In an optional embodiment, the hydrogen production system further comprises a cold energy air separation system; The cold energy storage system is connected to the cold energy air separation system through the fifth refrigerant circulation pipeline and the sixth refrigerant circulation pipeline, and the cold energy air separation system is connected to the hydrogen liquefaction system through the first liquid nitrogen circulation pipeline and the second liquid nitrogen circulation pipeline; The cold energy storage system is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system has a cold extraction zone including a first temperature zone; Cold energy air separation system, used to utilize the cold energy in the first temperature zone to separate air and obtain liquid nitrogen; The hydrogen liquefaction system is used to utilize the cold energy of the first temperature zone and liquid nitrogen to liquefy hydrogen to obtain liquid hydrogen.

[0011] In an optional embodiment, the hydrogen production system further includes a cold energy utilization system; The cold energy storage system is connected to the cold energy utilization system through the fifth refrigerant circulation pipeline and the sixth refrigerant circulation pipeline; The cold energy storage system is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system has a first temperature zone, a second temperature zone and a third temperature zone; A cold energy utilization system, used for graded utilization of cold energy in the first temperature zone, the second temperature zone and the third temperature zone; The hydrogen liquefaction system is used to utilize the cold energy in the first temperature zone to liquefy hydrogen to obtain liquid hydrogen.

[0012] In an optional embodiment, the liquid hydrogen gasification system is connected to the cold energy storage system through the seventh refrigerant circulation pipeline and the eighth refrigerant circulation pipeline.

[0013] In an optional embodiment, the hydrogen production system further includes a blending control valve and a natural gas hydrogen blending system; The LNG cold energy power generation system and the LNG gasification system are both connected to the natural gas transmission pipeline, and the natural gas transmission pipeline is connected to the blending control valve; The blending control valve is connected to the natural gas hydrogen blending system through a natural gas transmission bypass pipeline; The liquid hydrogen gasification system is connected to the natural gas hydrogen blending system through a hydrogen pipeline.

[0014] In a second aspect, an embodiment of the present application provides a co-production process method, which is applied to a co-production process system provided in any of the above embodiments, and the method includes: The microgrid on the station supplies power to the process systems on the station, including the natural gas production system and the hydrogen production system. The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released during the gasification process; The hydrogen production system produces hydrogen and uses the stored cold energy to liquefy and store the produced hydrogen. When there is a demand for hydrogen export downstream, the stored liquid hydrogen is gasified to obtain hydrogen.

[0015] In an optional embodiment, the hydrogen production system further includes a blending control valve and a natural gas hydrogen blending system; the method further includes: If the mixing control valve receives the mixing control signal, it performs a closing operation; The natural gas hydrogen blending system mixes natural gas and hydrogen in a preset ratio, and then outputs the mixture to the outside through a hydrogen blending transmission pipeline and a hydrogen blending transmission metering system.

[0016] The embodiment of the present application provides a co-production process system, which includes an in-station microgrid and an in-station process system. The in-station microgrid supplies power to the in-station process system. The in-station process system includes a natural gas production system and a hydrogen production system. The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released during the gasification process; the hydrogen production system produces hydrogen, and uses the stored cold energy to liquefy, store and gasify the produced hydrogen. The technical solution provided by the present application can realize the coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage, gasification and other processes, realize the integration of the normal production of the LNG receiving station and the whole process of hydrogen production, storage and transportation, and can fully and deeply integrate the LNG industry chain with the hydrogen energy industry chain, realize the efficient utilization of energy and the comprehensive supply of energy, and promote the co-construction and sharing of infrastructure in energy transformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a co-production process system provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of another co-production process system provided in an embodiment of the present application; Figure 3 A schematic flow chart of a co-production process provided in an embodiment of the present application.

[0018] Description of the accompanying drawings: 101-LNG supply system, 113-first LNG delivery pipeline, 112-second LNG delivery pipeline; 401-external power supply network, 402-microgrid within the station, 421-LNG cold energy power generation system, 423-new energy power generation system, 422-energy storage system within the station, 411-grid within the station; 102-in-station process system, 105-natural gas production system, 103-LNG gasification system, 104-cold energy storage system, 201-water electrolysis hydrogen production system, 202-hydrogen liquefaction system, 203-liquid hydrogen storage system, 204-liquid hydrogen gasification system, 301-cold energy air separation system, 302-cold energy utilization system, 119-blending control valve, 205-natural gas hydrogen blending system; 117-first refrigerant circulation pipeline, 118-second refrigerant circulation pipeline, 121-third refrigerant circulation pipeline Refrigerant circulation pipeline, 122-fourth refrigerant circulation pipeline, 311-fifth refrigerant circulation pipeline, 312-sixth refrigerant circulation pipeline, 241-seventh refrigerant circulation pipeline, 242-eighth refrigerant circulation pipeline, 231-first liquid nitrogen circulation pipeline, 232-second liquid nitrogen circulation pipeline, 211-hydrogen transmission pipeline, 212-liquid hydrogen transmission pipeline, 214-liquid hydrogen external transmission pipeline, 115-natural gas external transmission pipeline, 116-natural gas external transmission bypass pipeline, 215-hydrogen pipeline; 106-Natural gas export metering system, 206-Hydrogen blending export metering system, 216-Hydrogen blending export pipeline. DETAILED DESCRIPTION

[0019] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0020] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but only as an example of an embodiment. Other modifications within the scope and spirit of the present application will occur to those skilled in the art.

[0021] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0022] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0023] It should also be understood that although the present application has been described with reference to some specific examples, those skilled in the art will be able to readily implement many other equivalent forms of the present application.

[0024] The above and other aspects, features and advantages of the present application will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings.

[0025] Specific embodiments of the present application are described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments applied for are merely examples of the present application, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that obscure the present application. Therefore, the specific structural and functional details applied for herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present application in a variety of ways with substantially any suitable detailed structure.

[0026] This specification may use the phrases "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present application.

[0027] A co-production process system provided in an embodiment of the present application is described in detail below with reference to the accompanying drawings.

[0028] See also Figure 1 and Figure 2An embodiment of the present application provides a cogeneration process system for providing natural gas and hydrogen. The cogeneration process system includes: an on-site process system 102 and an on-site microgrid 402 capable of supplying power to the on-site process system 102 .

[0029] The in-station process system 102 includes a natural gas production system 105 and a hydrogen production system. The natural gas production system 105 may include an LNG gasification system 103, a cold energy storage system 104, etc., and the hydrogen production system may include a water electrolysis hydrogen production system 201, a hydrogen liquefaction system 202, a liquid hydrogen storage system 203, a liquid hydrogen gasification system 204, a cold energy air separation system 301, a cold energy utilization system 302, a blending control valve 19, a natural gas hydrogen blending system 205, etc.

[0030] The natural gas production system 105 is used to gasify the received liquefied natural gas to obtain natural gas, and store the cold energy released during the gasification process.

[0031] The hydrogen production system is connected to the natural gas production system 105, and is used to produce hydrogen, and utilize the stored cold energy to liquefy, store and gasify the produced hydrogen.

[0032] The co-production process system provided in the embodiment of the present application can realize the coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage, gasification and other processes, realize the full process integration of normal production of LNG receiving stations and hydrogen production, storage and transportation, and can fully and deeply integrate the LNG industry chain with the hydrogen energy industry chain, realize efficient energy utilization and comprehensive energy supply, and promote the joint construction and sharing of infrastructure in energy transformation.

[0033] In some embodiments, see Figure 1 and Figure 2 The in-station microgrid 402 includes an LNG cold energy power generation system 421, a new energy power generation system 423 and an in-station energy storage system 422.

[0034] The LNG supply system 101 is connected to the LNG cold energy power generation system 421 through the first LNG transmission pipeline 113 .

[0035] The LNG cold energy power generation system 421 is connected to the in-station energy storage system 422 via the in-station power grid 411; The new energy power generation system 423 is connected to the in-station energy storage system 422 via the in-station power grid 411; The on-site energy storage system 422 is connected to the on-site process system 102 via the on-site power grid 411 .

[0036] Specifically, the LNG supply system 101 is used to transport liquefied natural gas to the LNG cold energy power generation system 421 .

[0037] The LNG cold energy power generation system 421 is used to receive liquefied natural gas provided by the LNG supply system 101 and utilize the liquefied natural gas to generate cold energy.

[0038] The new energy power generation system 423 is used to generate new energy using new energy raw materials in the station. Specifically, the new energy power generation system 423 mainly generates electricity by installing photovoltaic and solar thermal power generation devices in the station, and the generated energy can only be used to power the process system 102 in the station.

[0039] The in-station energy storage system 422 is used to store the electric energy provided by the LNG cold energy power generation system 421 and the new energy power generation system 423, and to supply power to the in-station process system 102. Specifically, the in-station energy storage system 422 stores electric energy in various forms such as liquid air energy storage, electrochemical energy storage, and electromagnetic energy storage when the electricity price is low or when the in-station process system 102 cannot absorb the electricity generated by new energy power generation and LNG cold energy power generation, so as to achieve the purpose of shaving peaks and filling valleys and reducing the purchase of electricity from the external power supply network 401.

[0040] Optionally, the in-station microgrid 402 also includes related transmission and distribution stations and their grid control systems (not shown in the figure). The LNG cold energy power generation system 421, the new energy power generation system 423, and the in-station energy storage system 422 are connected to the substation through the in-station grid 411, and the substation uniformly regulates the voltage and supplies power to the in-station process system 102.

[0041] Optionally, after the in-station energy storage system 422 is connected to the in-station power grid 411, it stores electric energy according to its own capacity and fluctuations in the power load in the station.

[0042] Optionally, the on-site microgrid 402 is equipped with a power grid control system, which is used to control the storage and power supply of electric energy of the on-site energy storage system. Specifically, it may include: through real-time access to the overall power load demand, power supply capacity, and remaining capacity of the energy storage system, through the built-in optimization scheduling algorithm for control, and giving instructions for energy storage and energy use, the instructions include: external power purchase, external power purchase time period, energy storage system operation plan, etc.

[0043] Optionally, the priority of electricity consumption of the on-site microgrid 402 is LNG cold energy power generation system 421, new energy power generation system 423, on-site energy storage system 422, and external power supply network 401.

[0044] It can be understood that the in-station microgrid 402 uses multiple power sources such as LNG cold energy power generation and new energy power generation to reduce the purchase of electricity from the external power supply network 401. The in-station microgrid 402 gives priority to supplying power to the in-station process system 102. When the power of the in-station microgrid 402 is insufficient, it purchases electricity from the external power supply network 401.

[0045] In some embodiments, see Figure 1 and Figure 2 , the natural gas production system 105 includes an LNG gasification system 103 and a cold energy storage system 104; The LNG supply system 101 is connected to the LNG gasification system 103 via a second LNG delivery pipeline 112; The LNG gasification system 103 is connected to the cold energy storage system 104 via a first refrigerant circulation pipeline 117 and a second refrigerant circulation pipeline 118 .

[0046] Specifically, the LNG supply system 101 is used to transport liquefied natural gas to the LNG gasification system 103 .

[0047] The in-station LNG gasification system 103 is used to receive the liquefied natural gas provided by the LNG supply system 101 , and gasify the liquefied natural gas to obtain natural gas which enters the natural gas transmission pipeline 115 .

[0048] Optionally, when the temperature of the natural gas obtained after gasification cannot meet the required temperature for external transmission, a first-level temperature compensator can be added to compensate the temperature of the natural gas. The heat source of the temperature compensator includes but is not limited to: seawater, air, solar energy or electricity.

[0049] The cold energy storage system 104 is used to extract and store the cold energy released during the liquefied natural gas gasification process in different temperature zones, and release the cold energy when the downstream cold energy utilization equipment is working, so as to achieve the cross-time allocation of the cold energy of liquefied natural gas gasification. The cold energy utilization equipment may include a cold energy air separation system or a cold energy utilization system.

[0050] The in-station LNG gasification system 103 is connected to the cold energy storage system 104 through different refrigerant circulation pipelines. The optional refrigerants include but are not limited to: R744, R134a, ethylene glycol solution, and R290.

[0051] In some embodiments, see Figure 1 and Figure 2 , the hydrogen production system includes a water electrolysis hydrogen production system 201, a hydrogen liquefaction system 202, a liquid hydrogen storage system 203 and a liquid hydrogen gasification system 204; The water electrolysis hydrogen production system 201 is connected to the hydrogen liquefaction system 202 via a hydrogen delivery pipeline 211; The cold energy storage system 104 is connected to the hydrogen liquefaction system 202 via the third coolant circulation pipeline 121 and the fourth coolant circulation pipeline 122; The hydrogen liquefaction system 202 is connected to the liquid hydrogen storage system 203 via a liquid hydrogen delivery pipeline 212; The liquid hydrogen storage system 203 is connected to the liquid hydrogen gasification system 204 via a liquid hydrogen transmission pipeline 214 .

[0052] Specifically, the LNG supply system 101 is used to transport liquefied natural gas to the water electrolysis hydrogen production system 201 .

[0053] The water electrolysis hydrogen production system 201 is used to produce hydrogen using water electrolysis hydrogen production technology.

[0054] The hydrogen liquefaction system 202 is used to utilize cold energy to liquefy hydrogen to obtain liquid hydrogen.

[0055] The liquid hydrogen storage system 203 is used to store liquid hydrogen at normal pressure or slightly positive pressure; The liquid hydrogen gasification system 204 is used to gasify liquid hydrogen to obtain hydrogen.

[0056] In a specific embodiment, see Figure 1 , the hydrogen production system also includes a cold energy air separation system 301; Specifically, the cold energy storage system 104 is connected to the cold energy air separation system 301 through the fifth refrigerant circulation pipeline 311 and the sixth refrigerant circulation pipeline 312, and the cold energy air separation system 301 is connected to the hydrogen liquefaction system 202 through the first liquid nitrogen circulation pipeline 231 and the second liquid nitrogen circulation pipeline 232.

[0057] Specifically, the cold energy storage system 104 is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system 104 may include a first temperature zone; optionally, the first temperature zone may be -160°C-155°C.

[0058] The cold energy air separation system 301 mainly utilizes the cold energy in the first temperature zone to separate air to obtain liquid nitrogen, which can be further used as a secondary pre-cooling medium in the hydrogen liquefaction process of the hydrogen liquefaction system 202. The temperature of the liquid nitrogen product is -210℃~-196℃ (degrees Celsius).

[0059] The hydrogen liquefaction system 202 is used to utilize the cold energy of the first temperature zone and liquid nitrogen to liquefy hydrogen to obtain liquid hydrogen.

[0060] In this embodiment, the main cooling range of the cold energy storage system 104 is mainly -160°C-155°C, and the cold energy is mainly used for the second-stage pre-cooling of the hydrogen liquefaction system 202 and the circulating nitrogen cooling of the cold energy air separation system 301.

[0061] The water electrolysis hydrogen production system 201 transports the produced hydrogen to the hydrogen liquefaction system 202 through the hydrogen transportation pipeline 211 .

[0062] The hydrogen liquefaction system 202 is connected to the cold energy storage system 104 through the third refrigerant circulation pipeline 121 and the fourth refrigerant circulation pipeline 122, and is also connected to the hydrogen liquefaction system 202 through the first liquid nitrogen circulation pipeline 231 and the second liquid nitrogen circulation pipeline 232. The hydrogen liquefaction system 202 utilizes the cold energy provided by the cold energy storage system 104 and the cold energy air separation system 301 to liquefy the hydrogen obtained by the water electrolysis hydrogen production system 201 to obtain liquid hydrogen, and the liquefaction process includes normal-para conversion.

[0063] During the hydrogen liquefaction process, different grades of cold energy from the cold energy storage system 104 can be used at different liquefaction stages to achieve the target liquefaction temperature.

[0064] The liquid hydrogen storage system 203 is connected to the hydrogen liquefaction system 202 via a liquid hydrogen delivery pipeline 212. The liquid hydrogen storage system 203 is used to store liquid hydrogen at normal pressure or slightly positive pressure, and the storage pressure is 0.1~0.5MPag.

[0065] The liquid hydrogen gasification system 204 is connected to the liquid hydrogen storage system 203 via a liquid hydrogen export pipeline 214, and is used to gasify the liquid hydrogen to obtain hydrogen when there is a demand for hydrogen export downstream.

[0066] In another specific embodiment, see Figure 2 , the hydrogen production system also includes a cold energy utilization system 302; The cold energy storage system 104 is connected to the cold energy utilization system 302 via the fifth coolant circulation pipeline 311 and the sixth coolant circulation pipeline 312 .

[0067] The cold energy storage system 104 is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system 104 can include a first temperature zone, a second temperature zone and a third temperature zone; optionally, the first temperature zone can be -160℃-155℃, the second temperature zone can be -100~-120℃, and the third temperature zone can be -60~0℃.

[0068] Optionally, the cold energy utilization system 302 is used to utilize the cold energy of the first temperature zone, the second temperature zone and the third temperature zone in a graded manner.

[0069] Specifically, the cold energy utilization system 302 is connected to the cold energy storage system 104 through the fifth refrigerant circulation pipeline 311 and the sixth refrigerant circulation pipeline 312 to realize the extraction and utilization of the cold energy stored in the cold energy storage system 104. The cold energy utilization system 302 utilizes the cold energy of different grades of the cold energy storage system 104 in a graded manner, and the main utilization methods include but are not limited to: low-temperature crushing, CO2 liquefaction, seawater desalination, food crushing, freezing, refrigeration, air conditioning, etc. Further, the cold energy utilization system 302 can utilize the cold energy in the first temperature zone for low-temperature crushing, etc., utilize the cold energy in the second temperature zone for CO2 liquefaction, seawater desalination, food crushing, etc., and utilize the cold energy in the third temperature zone for freezing, refrigeration, air conditioning, etc. The hydrogen liquefaction system 202 is used to utilize the cold energy in the first temperature zone and liquid nitrogen to liquefy hydrogen to obtain liquid hydrogen.

[0070] In this embodiment, the main cooling ranges of the cold energy storage system 104 are -160℃-155℃, -100~-120℃, and -60~0℃, and the main destination of the cold energy is the second-stage precooling of the hydrogen liquefaction system 202 and the cold energy utilization system 302.

[0071] The water electrolysis hydrogen production system 201 transports the produced hydrogen to the hydrogen liquefaction system 202 through the hydrogen transportation pipeline 211 .

[0072] The hydrogen liquefaction system 202 is connected to the cold energy storage system 104 through the third refrigerant circulation pipeline 121 and the fourth refrigerant circulation pipeline 122, and is also connected to the hydrogen liquefaction system 202 through the first liquid nitrogen circulation pipeline 231 and the second liquid nitrogen circulation pipeline 232. The hydrogen liquefaction system 202 utilizes the cold energy provided by the cold energy storage system 104 and the cold energy air separation system 301 to liquefy the hydrogen obtained by the water electrolysis hydrogen production system 201 to obtain liquid hydrogen, and the liquefaction process includes normal-para conversion.

[0073] During the hydrogen liquefaction process, different grades of cold energy from the cold energy storage system 104 can be used at different liquefaction stages to achieve the target liquefaction temperature.

[0074] The liquid hydrogen storage system 203 is connected to the hydrogen liquefaction system 202 via a liquid hydrogen delivery pipeline 212. The liquid hydrogen storage system 203 is used to store liquid hydrogen at normal pressure or slightly positive pressure, and the storage pressure is 0.1~0.5MPag.

[0075] The liquid hydrogen gasification system 204 is connected to the liquid hydrogen storage system 203 via a liquid hydrogen export pipeline 214, and is used to gasify the liquid hydrogen to obtain hydrogen when there is a demand for hydrogen export downstream.

[0076] In some embodiments, see Figure 2The liquid hydrogen gasification system 204 is connected to the cold energy storage system 104 through the seventh coolant circulation pipeline 241 and the eighth coolant circulation pipeline 242, and is used to collect the cold energy in the liquid hydrogen gasification process and transport it to the cold energy storage system 104 for cold energy utilization and hydrogen liquefaction. The connection relationship between the liquid hydrogen gasification system 204 and the cold energy storage system 104 is also applicable to Figure 1 The liquid hydrogen gasification system 204 and the cold energy storage system 104 in Figure 1 In the example, the liquid hydrogen gasification system 204 can also be connected to the cold energy storage system 104 through the seventh coolant circulation pipeline 241 and the eighth coolant circulation pipeline 242. Figure 1 The connection between the liquid hydrogen gasification system 204 and the cold energy storage system 104 is not shown.

[0077] In some embodiments, see Figure 1 and Figure 2 , the hydrogen production system also includes a blending control valve 119 and a natural gas hydrogen blending system 205; The LNG cold energy power generation system 421 and the LNG gasification system 103 are both connected to the natural gas transmission pipeline 115, and the natural gas transmission pipeline 115 is connected to the blending control valve 119; The blending control valve 119 is connected to the natural gas hydrogen blending system 205 through the natural gas transmission bypass pipeline 116; The liquid hydrogen gasification system 204 is connected to the natural gas hydrogen blending system 205 via a hydrogen pipeline 215 .

[0078] Specifically, the LNG cold energy power generation system 421 is also used to gasify the liquefied natural gas to obtain natural gas which enters the natural gas transmission pipeline 115. The LNG gasification system 103 enters the natural gas obtained by gasification into the natural gas transmission pipeline 115.

[0079] The natural gas transmission pipeline 115 is connected to the blending control valve 119 and the natural gas transmission metering system 106 respectively.

[0080] The blending control valve 119 is connected to the natural gas hydrogen blending system 205 through the natural gas export bypass pipeline 116; the liquefied hydrogen gasification system 204 is connected to the natural gas hydrogen blending system 205 through the hydrogen pipeline 215, and the natural gas hydrogen blending system 205 is connected to the hydrogen export metering system 206 through the hydrogen export pipeline 216.

[0081] Specifically, the mixing control valve is used to receive a control signal and perform shutoff and closing operations.

[0082] If the blending control valve receives the blending control signal, it performs a closing operation, and the natural gas hydrogen blending system 205 mixes the natural gas and hydrogen in a preset ratio, and then outputs the mixture to the outside through the hydrogen blending transmission pipeline 216 and the hydrogen blending transmission metering system 206 .

[0083] Optionally, the mixing ratio of natural gas and hydrogen is in the range of 3% to 10%, that is, the ratio of hydrogen to the mixed gas is: not less than 3% and not more than 10%; wherein the mixed gas includes hydrogen and natural gas.

[0084] In this embodiment, whether to mix and output and the mixing ratio can be determined by controlling the switch and opening of the mixing control valve 119.

[0085] If the blending control valve receives a separation control signal, it performs a shut-off operation, and the natural gas and hydrogen are not mixed. The natural gas and hydrogen are output separately. The natural gas is output to the outside through the natural gas output pipeline 115 and the natural gas output metering system 106, and the hydrogen is output to the outside through the natural gas hydrogen blending system 205 and the hydrogen blending output pipeline 216 and the hydrogen blending output metering system 206.

[0086] Based on the same inventive concept, see Figure 3 The embodiment of the present application provides a co-production process method, which is applied to the co-production process system provided in any of the above embodiments. The co-production process method includes: S100: The microgrid in the station supplies power to the process systems in the station; the process systems in the station include the natural gas production system and the hydrogen production system; S200: The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released during the gasification process; S300: The hydrogen production system produces hydrogen, and uses the stored cold energy to liquefy and store the produced hydrogen. When there is a demand for hydrogen export downstream, the stored liquid hydrogen is gasified to obtain hydrogen.

[0087] The co-production process method provided in the embodiment of the present application can realize the coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage, gasification and other processes, realize the full process integration of normal production of LNG receiving stations and hydrogen production, storage and transportation, and can fully and deeply integrate the LNG industry chain with the hydrogen energy industry chain, realize efficient energy utilization and comprehensive energy supply, and promote the joint construction and sharing of infrastructure in energy transformation.

[0088] Optionally, the natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released during the gasification process, specifically including: The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and extracts and stores the cold energy released during the gasification process in different temperature zones; In the case where the hydrogen production system includes a cold energy air separation system, the cold extraction zone includes a first temperature zone; In the case where the hydrogen production system includes a cold energy utilization system, the cold energy extraction interval includes a first temperature zone, a second temperature zone and a third temperature zone.

[0089] Optionally, the produced hydrogen is liquefied using the stored cold energy, specifically comprising: when the hydrogen production system includes a cold energy air separation system, using the cold energy of the first temperature zone to separate air to obtain liquid nitrogen, and using the cold energy of the first temperature zone and the liquid nitrogen to liquefy the hydrogen to obtain liquid hydrogen.

[0090] When the hydrogen production system includes a cold energy utilization system, the cold energy of the first temperature zone, the second temperature zone and the third temperature zone is utilized in stages, and the cold energy of the first temperature zone is utilized to liquefy hydrogen to obtain liquid hydrogen.

[0091] In some embodiments, the hydrogen production system further includes a blending control valve and a natural gas hydrogen blending system; the method further includes: If the mixing control valve receives the mixing control signal, it performs a closing operation; The natural gas hydrogen blending system mixes natural gas and hydrogen in a preset ratio and then outputs the mixture to the outside through the hydrogen blending transmission pipeline and the hydrogen blending transmission metering system; The ratio of hydrogen to mixed gas is no less than 3% and no more than 10%; the mixed gas includes hydrogen and natural gas.

[0092] If the blending control valve receives a separation control signal, it performs a shut-off operation; the natural gas and hydrogen are not mixed, the natural gas is output to the outside through the natural gas transmission pipeline and the natural gas transmission metering system, and the hydrogen is output to the outside through the natural gas blending system, the hydrogen blending transmission pipeline and the hydrogen blending transmission metering system 206.

[0093] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. A co-production process system, characterized in that: Used to provide natural gas and hydrogen, the system comprises: an on-site process system and an on-site microgrid capable of supplying power to the on-site process system; The process system in the station includes a natural gas production system and a hydrogen production system; The natural gas production system is used to gasify the received liquefied natural gas to obtain natural gas, and store the cold energy released during the gasification process; The hydrogen production system is connected to the natural gas production system, and is used to produce hydrogen, and utilizes the stored cold energy to liquefy, store and gasify the produced hydrogen.

2. The system according to claim 1, characterized in that The in-station microgrid includes an LNG cold energy power generation system, a new energy power generation system, an in-station energy storage system and a power grid control system; The LNG supply system is connected to the LNG cold energy power generation system through a first LNG transmission pipeline; The LNG cold energy power generation system is connected to the in-station energy storage system through the in-station power grid, and is used to generate cold energy using the received liquefied natural gas; The new energy power generation system is connected to the in-station energy storage system through the in-station power grid, and is used to generate new energy using the new energy raw materials in the station; The in-station energy storage system is connected to the in-station process system through the in-station power grid, and is used to store the electric energy provided by the LNG cold energy power generation system and the new energy power generation system, and to supply power to the in-station process system; The power grid control system is used to control the storage and power supply of electric energy of the in-station energy storage system.

3. The system according to claim 2, characterized in that The natural gas production system includes an LNG gasification system and a cold energy storage system; The LNG supply system is connected to the LNG gasification system through a second LNG transmission pipeline; The LNG gasification system is connected to the cold energy storage system through a first refrigerant circulation pipeline and a second refrigerant circulation pipeline.

4. The system according to claim 3, characterized in that The hydrogen production system includes a water electrolysis hydrogen production system, a hydrogen liquefaction system, a liquid hydrogen storage system and a liquid hydrogen gasification system; The water electrolysis hydrogen production system is connected to the hydrogen liquefaction system via a hydrogen delivery pipeline; The cold energy storage system is connected to the hydrogen liquefaction system through a third coolant circulation pipeline and a fourth coolant circulation pipeline; The hydrogen liquefaction system is connected to the liquid hydrogen storage system via a liquid hydrogen delivery pipeline; The liquid hydrogen storage system is connected to the liquid hydrogen gasification system via a liquid hydrogen transmission pipeline.

5. The system according to claim 4, characterized in that The hydrogen production system also includes a cold energy air separation system; The cold energy storage system is connected to the cold energy air separation system through the fifth refrigerant circulation pipeline and the sixth refrigerant circulation pipeline, and the cold energy air separation system is connected to the hydrogen liquefaction system through the first liquid nitrogen circulation pipeline and the second liquid nitrogen circulation pipeline; The cold energy storage system is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system includes a first temperature zone; The cold energy air separation system is used to utilize the cold energy in the first temperature zone to separate air and obtain liquid nitrogen; The hydrogen liquefaction system is used to utilize the cold energy of the first temperature zone and the liquid nitrogen to liquefy hydrogen to obtain liquid hydrogen.

6. The system according to claim 4, characterized in that The hydrogen production system also includes a cold energy utilization system; The cold energy storage system is connected to the cold energy utilization system through the fifth coolant circulation pipeline and the sixth coolant circulation pipeline; The cold energy storage system is used to extract and store the cold energy released during the gasification process of liquefied natural gas in different temperature zones; the cold energy storage system has a first temperature zone, a second temperature zone and a third temperature zone; The cold energy utilization system is used to utilize the cold energy of the first temperature zone, the second temperature zone and the third temperature zone in a graded manner; The hydrogen liquefaction system is used to utilize the cold energy in the first temperature zone to liquefy hydrogen to obtain liquid hydrogen.

7. The system according to claim 5 or 6, characterized in that: The liquid hydrogen gasification system is connected to the cold energy storage system through a seventh refrigerant circulation pipeline and an eighth refrigerant circulation pipeline.

8. The system according to claim 4, characterized in that The hydrogen production system also includes a blending control valve and a natural gas hydrogen blending system; The LNG cold energy power generation system and the LNG gasification system are both connected to a natural gas transmission pipeline, and the natural gas transmission pipeline is connected to the blending control valve; The blending control valve is connected to the natural gas hydrogen blending system via a natural gas transmission bypass pipeline; The liquid hydrogen gasification system is connected to the natural gas hydrogen blending system through a hydrogen pipeline.

9. A co-production process, characterized in that: Applied to the co-production process system according to any one of claims 1 to 8, the method comprises: The in-station microgrid supplies power to the in-station process system; wherein the in-station process system includes a natural gas production system and a hydrogen production system; The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released during the gasification process; The hydrogen production system produces hydrogen, and uses the stored cold energy to liquefy and store the produced hydrogen. When there is a demand for hydrogen export downstream, the stored liquid hydrogen is gasified to obtain hydrogen.

10. The method according to claim 9, characterized in that The hydrogen production system also includes a blending control valve and a natural gas hydrogen blending system; the method also includes: If the mixing control valve receives the mixing control signal, it performs a closing operation; The natural gas hydrogen blending system mixes natural gas and hydrogen in a preset ratio, and then outputs the mixture to the outside through a hydrogen blending transmission pipeline and a hydrogen blending transmission metering system.

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