Integrated process system and integrated process method

Abstract

The application 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 comprises an in-station process system and an in-station micro-grid capable of supplying power for the in-station process system. The in-station process system comprises a natural gas production system and a hydrogen production system. The natural gas production system is used for gasifying received liquefied natural gas to obtain natural gas, and storing cold energy released in the gasification process. The hydrogen production system is connected with the natural gas production system, and is used for producing hydrogen, and liquefying, storing and gasifying the produced hydrogen by using the stored cold energy. By adopting the embodiment of the application, the process coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage and gasification can be realized, the normal production of an LNG receiving station and the whole-process integration of hydrogen production, storage and transportation can be realized, and the LNG industrial chain and the hydrogen energy industrial chain can be fully and deeply integrated.

Description

TECHNICAL FIELD

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

[0002] With the acceleration of global energy transformation and the improvement of environmental awareness, hydrogen energy, as one of the representatives of clean energy, will continue to grow in market demand. As an important way of hydrogen energy storage and transportation, liquid hydrogen has the advantages of high hydrogen storage density, high filling 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 cost of liquid hydrogen will gradually decrease. According to the prediction of the agency, by 2050, the cost of liquid hydrogen storage and transportation is expected to decrease by 50% to 8-10 yuan / kg, which will further promote the large-scale application of liquid hydrogen. LNG (Liquefied Natural Gas) and hydrogen industry have a close relationship, and can help the development of hydrogen industry chain by relying on the mature system of LNG industry, and realize the deep integration of the two.

[0003] In recent years, scholars have done a lot of research on hydrogen liquefaction process using LNG cold energy. In related technologies, LNG and hydrogen production are simply coupled.

[0004] How to provide a production process that can fully and deeply integrate the LNG industry chain and the hydrogen energy industry chain is a problem that needs to be solved by those skilled in the art. SUMMARY

[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, the embodiments of the present application provide a co-production process system for providing natural gas and hydrogen, the system comprising: an in-station process system and an in-station micro-grid capable of supplying power to the in-station process system;

[0007] The in-station process system comprises a natural gas production system and a hydrogen production system;

[0008] The natural gas production system is configured to gasify the received liquefied natural gas to obtain natural gas, and store the cold energy released in the gasification process;

[0009] The hydrogen production system is connected with the natural gas production system, and is configured to produce hydrogen, and liquefy, store and gasify the produced hydrogen by using the stored cold energy.

[0010] In an optional embodiment, the in-station micro-grid comprises an LNG cold energy power generation system, a new energy power generation system, an in-station energy storage system and a grid control system;

[0011] The LNG supply system is connected with the LNG cold energy power generation system through a first LNG conveying pipeline;

[0012] The LNG cold energy power generation system is connected with the station internal energy storage system through the station internal power grid, and is used for generating power by using the received liquefied natural gas;

[0013] The new energy power generation system is connected with the station internal energy storage system through the station internal power grid, and is used for generating power by using the station internal new energy raw materials;

[0014] The station internal energy storage system is connected with the station internal process system through the station internal power grid, and is used for storing the electric energy provided by the LNG cold energy power generation system and the new energy power generation system, and supplying power to the station internal process system 102;

[0015] The power grid regulation and control system is used for regulating and controlling the storage and power supply of the electric energy of the station internal energy storage system.

[0016] In an optional implementation, the natural gas production system comprises an LNG gasification system and a cold energy storage system;

[0017] The LNG supply system is connected with the LNG gasification system through a second LNG conveying pipeline;

[0018] The LNG gasification system is connected with the cold energy storage system through a first cold carrier circulating pipeline and a second cold carrier circulating pipeline.

[0019] In an optional implementation, the hydrogen production system comprises an electrolytic water hydrogen production system, a hydrogen liquefaction system, a liquid hydrogen storage system and a liquid hydrogen gasification system;

[0020] The electrolytic water hydrogen production system is connected with the hydrogen liquefaction system through a hydrogen conveying pipeline;

[0021] The cold energy storage system is connected with the hydrogen liquefaction system through a third cold carrier circulating pipeline and a fourth cold carrier circulating pipeline;

[0022] The hydrogen liquefaction system is connected with the liquid hydrogen storage system through a liquid hydrogen conveying pipeline;

[0023] The liquid hydrogen storage system is connected with the liquid hydrogen gasification system through a liquid hydrogen external conveying pipeline.

[0024] In an optional implementation, the hydrogen production system further comprises a cold energy air separation system;

[0025] The cold energy storage system is connected with the cold energy air separation system through a fifth cold carrier circulating pipeline and a sixth cold carrier circulating pipeline, and the cold energy air separation system is connected with the hydrogen liquefaction system through a first liquid nitrogen circulating pipeline and a second liquid nitrogen circulating pipeline;

[0026] The cold energy extraction and storage system is used for extracting and storing cold energy in different temperature zones released in the LNG gasification process.

[0027] The cold energy air separation system is used for separating air to obtain liquid nitrogen by using the cold energy in the first temperature zone.

[0028] The hydrogen liquefaction system is used for liquefying hydrogen to obtain liquid hydrogen by using the cold energy in the first temperature zone and the liquid nitrogen.

[0029] In an optional embodiment, the hydrogen production system further comprises a cold energy utilization system.

[0030] The cold energy extraction and storage system is connected with the cold energy utilization system through the fifth and sixth cold carrier circulation pipelines.

[0031] The cold energy extraction and storage system is used for extracting and storing cold energy in different temperature zones released in the LNG gasification process.

[0032] The cold energy utilization system is used for utilizing the cold energy in the first, second and third temperature zones in stages.

[0033] The hydrogen liquefaction system is used for liquefying hydrogen to obtain liquid hydrogen by using the cold energy in the first temperature zone.

[0034] In an optional embodiment, the liquid hydrogen gasification system is connected with the cold energy extraction and storage system through the seventh and eighth cold carrier circulation pipelines.

[0035] In an optional embodiment, the hydrogen production system further comprises a blending control valve and a natural gas hydrogen blending system.

[0036] The LNG cold energy power generation system and the LNG gasification system are connected to the natural gas external pipeline, and the natural gas external pipeline is connected to the blending control valve.

[0037] The blending control valve is connected to the natural gas hydrogen blending system through the natural gas external bypass pipeline.

[0038] The liquid hydrogen gasification system is connected to the natural gas hydrogen blending system through the hydrogen pipeline.

[0039] In a second aspect, the embodiments of the present application provide a cogeneration process method, applied to the cogeneration process system provided in any of the above embodiments, and the method comprises:

[0040] The on-site microgrid supplies power to the on-site process system; wherein the on-site process system comprises a natural gas production system and a hydrogen production system.

[0041] The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released in the gasification process;

[0042] The hydrogen production system produces hydrogen, and liquefies and stores the produced hydrogen by using the stored cold energy; in the case that there is a hydrogen delivery demand downstream, the stored liquid hydrogen is gasified to obtain hydrogen.

[0043] In an optional embodiment, the hydrogen production system further comprises a blending control valve and a natural gas hydrogen blending system; the method further comprises:

[0044] If the blending control valve receives a blending control signal, the blending control valve performs a closing operation;

[0045] The natural gas hydrogen blending system mixes natural gas and hydrogen according to a preset ratio, and then outputs the mixed natural gas and hydrogen to the outside through a hydrogen blending delivery pipeline and a hydrogen blending delivery metering system.

[0046] An integrated production process system provided by an embodiment of the present application includes an in-station micro-grid and an in-station process system, the in-station micro-grid 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 received liquefied natural gas to obtain natural gas, and stores cold energy released in the gasification process; the hydrogen production system produces hydrogen, and liquefies, stores and gasifies the produced hydrogen by using the stored cold energy. By using the technical solution provided by the present application, LNG gasification, cold energy storage, hydrogen production, liquefaction, storage and gasification can be coupled, normal production of an LNG receiving station and hydrogen production, storage and delivery can be integrated, LNG industry chains and hydrogen energy industry chains can be fully and deeply integrated, efficient energy utilization and comprehensive energy supply can be realized, and infrastructure construction and sharing in energy transformation can be promoted. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 FIG. 1 is a structural schematic diagram of an integrated production process system provided by an embodiment of the present application;

[0048] Figure 2 FIG. 2 is another structural schematic diagram of an integrated production process system provided by an embodiment of the present application;

[0049] Figure 3 FIG. 3 is a flow schematic diagram of an integrated production process method provided by an embodiment of the present application.

[0050] IDENTIFICATION OF DRAWINGS:

[0051] 101-LNG supply system, 113-first LNG delivery pipeline, 112-second LNG delivery pipeline;

[0052] 401-external power supply network, 402-in-station micro-grid, 421-LNG cold energy power generation system, 423-new energy power generation system, 422-in-station energy storage system, 411-in-station power grid;

[0053] 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 cold carrier circulating pipeline, 118-second cold carrier circulating pipeline, 121-third cold carrier circulating pipeline, 122-fourth cold carrier circulating pipeline, 311-fifth cold carrier circulating pipeline, 312-sixth cold carrier circulating pipeline, 241-seventh cold carrier circulating pipeline, 242-eighth cold carrier circulating pipeline, 231-first liquid nitrogen circulating pipeline, 232-second liquid nitrogen circulating pipeline, 211-hydrogen conveying pipeline, 212-liquid hydrogen conveying pipeline, 214-liquid hydrogen delivery pipeline, 115-natural gas delivery pipeline, 116-natural gas delivery bypass pipeline, 215-hydrogen pipeline;

[0054] 106-natural gas delivery metering system, 206-hydrogen-blended delivery metering system, 216-hydrogen-blended delivery pipeline. DETAILED DESCRIPTION

[0055] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0056] It is to be understood that various alterations and modifications can be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as exemplification of the embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the application.

[0057] The accompanying drawings incorporated in and forming a part of the specification, illustrate embodiments of the present application and, together with the general description of the application given above, and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0058] These and other characteristics, features and advantages of the present application will become apparent from the following description, given, by way of non-limiting example only, with reference to the accompanying drawings.

[0059] It is also to be understood that even though a few examples of implementation of the present application are described in the specification, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art from this disclosure.

[0060] The above and other aspects, features, and advantages of the present application will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, when considered in conjunction with the following detailed description.

[0061] The specific embodiments of the present application are described hereinafter with reference to the drawings; however, it should be understood that the embodiments described are merely examples of the present application and can be carried out in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid obscuring the present application unnecessarily or redundantly. Therefore, the specific structural and functional details disclosed herein are not intended to limit the present application, but merely serve as a basis for the claims and a representative basis for teaching one of ordinary skill in the art to employ the present application in substantially any appropriate detailed structure.

[0062] The specification can use phrases such as "in one embodiment", "in another embodiment", "in yet another embodiment", or "in other embodiments", which can refer to one or more of the same or different embodiments according to the present application.

[0063] The co-production process system provided by the embodiments of the present application is described in detail below with reference to the drawings.

[0064] Referring to Figure 1 and Figure 2 , the co-production process system provided by the embodiments of the present application is used to provide natural gas and hydrogen, and the co-production process system comprises an on-site process system 102 and an on-site micro-grid 402 capable of supplying power to the on-site process system 102.

[0065] The on-site process system 102 comprises a natural gas production system 105 and a hydrogen production system. The natural gas production system 105 can comprise an LNG gasification system 103, a cold energy storage system 104, etc., and the hydrogen production system can comprise an electrolytic water 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 119, a natural gas hydrogen blending system 205, etc.

[0066] 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 in the gasification process.

[0067] The hydrogen production system is connected with the natural gas production system 105, and is used to produce hydrogen, and to liquefy, store and gasify the produced hydrogen by using the stored cold energy.

[0068] The co-production process system provided by the embodiments of the present application can realize the process coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage and gasification, realize the fusion of LNG receiving station normal production and hydrogen production, storage and transportation full process, can fully and deeply integrate the LNG industry chain and the hydrogen energy industry chain, realize the efficient use of energy and the comprehensive supply of energy, and promote the infrastructure construction and sharing in the energy transformation.

[0069] In some embodiments, referring to Figure 1 and Figure 2 , the in-station micro-grid 402 comprises an LNG cold energy power generation system 421, a new energy power generation system 423 and an in-station energy storage system 422.

[0070] The LNG supply system 101 is connected with the LNG cold energy power generation system 421 through a first LNG conveying pipeline 113.

[0071] The LNG cold energy power generation system 421 is connected with the in-station energy storage system 422 through an in-station power grid 411.

[0072] The new energy power generation system 423 is connected with the in-station energy storage system 422 through the in-station power grid 411.

[0073] The in-station energy storage system 422 is connected with the in-station process system 102 through the in-station power grid 411.

[0074] Specifically, the LNG supply system 101 is used to convey liquefied natural gas to the LNG cold energy power generation system 421.

[0075] The LNG cold energy power generation system 421 is used to receive the liquefied natural gas provided by the LNG supply system 101 and generate power by using the liquefied natural gas.

[0076] The new energy power generation system 423 is used to generate power by using in-station new energy raw materials. Specifically, the new energy power generation system 423 mainly generates power by installing photovoltaic and solar thermal power generation devices in the station, and the generated power can be used only to power the in-station process system 102.

[0077] The in-station energy storage system 422 is used to store the power provided by the LNG cold energy power generation system 421 and the new energy power generation system 423, and power the in-station process system 102. Specifically, the in-station energy storage system 422 stores power in the form of liquid air energy storage, electrochemical energy storage, electromagnetic energy storage, etc. when the electricity price is low or when the in-station process system 102 cannot consume the power generated by the new energy power generation and the LNG cold energy power generation, so as to achieve the purpose of peak load shifting and reducing the purchase of power from the external power supply network 401.

[0078] Optionally, the in-station micro-grid 402 further comprises a related power transmission and distribution station and its power grid control system (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 with the substation through the in-station power grid 411, and the substation uniformly regulates the voltage and then supplies power to the in-station process system 102.

[0079] Optionally, after the in-station energy storage system 422 is connected with the in-station power grid 411, it stores power according to its capacity and the fluctuation of in-station power consumption.

[0080] Optionally, the station micro-grid 402 is provided with a grid regulation system for regulating the storage and power supply of the station energy storage system, which can specifically include: through real-time access to the field power load demand, power supply capacity, and remaining capacity of the energy storage system, regulating through the built-in optimization scheduling algorithm, and giving energy storage and energy consumption instructions, including: purchased power, purchased power period, energy storage system operation plan, etc.

[0081] Optionally, the power consumption priority of the station micro-grid 402 is in turn the LNG cold energy power generation system 421, the new energy power generation system 423, the station energy storage system 422, and the external power supply network 401.

[0082] It can be understood that the station micro-grid 402 uses multiple forms of 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 station micro-grid 402 preferentially supplies power to the station process system 102, and when the power of the station micro-grid 402 is insufficient, it purchases power from the external power supply network 401.

[0083] In some embodiments, referring to Figure 1 and Figure 2 , the natural gas production system 105 includes an LNG gasification system 103 and a cold energy harvesting system 104;

[0084] The LNG supply system 101 is connected with the LNG gasification system 103 through a second LNG delivery pipeline 112;

[0085] The LNG gasification system 103 is connected with the cold energy harvesting system 104 through a first coolant circulation pipeline 117 and a second coolant circulation pipeline 118.

[0086] Specifically, the LNG supply system 101 is used to deliver liquefied natural gas to the LNG gasification system 103.

[0087] The station LNG gasification system 103 is used to receive liquefied natural gas provided by the LNG supply system 101, and to obtain natural gas by gasifying the liquefied natural gas, and then the natural gas enters the natural gas delivery pipeline 115.

[0088] Optionally, when the temperature of the natural gas obtained after gasification cannot meet the delivery demand temperature, a first temperature compensator can be added to compensate the temperature of the natural gas, and the heat source of the temperature compensator includes but is not limited to: seawater, air, solar energy or electric energy.

[0089] The cold energy extraction and storage system 104 is configured to extract and store cold energy at different temperature zones released during the gasification of the liquefied natural gas, and release the cold energy when the downstream cold energy utilization device is in operation, so as to realize the cross-time allocation of the cold energy released during the gasification of the liquefied natural gas. The cold energy utilization device can include a cold energy air separation system or a cold energy utilization system.

[0090] The LNG gasification system 103 in the station is connected to the cold energy extraction and storage system 104 through different cold carrier circulation pipelines. The optional cold carriers include but are not limited to R744, R134a, ethylene glycol solution, and R290.

[0091] In some embodiments, referring to 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.

[0092] The water electrolysis hydrogen production system 201 is connected to the hydrogen liquefaction system 202 through a hydrogen delivery pipeline 211.

[0093] The cold energy extraction and storage system 104 is connected to the hydrogen liquefaction system 202 through a third cold carrier circulation pipeline 121 and a fourth cold carrier circulation pipeline 122.

[0094] The hydrogen liquefaction system 202 is connected to the liquid hydrogen storage system 203 through a liquid hydrogen delivery pipeline 212.

[0095] The liquid hydrogen storage system 203 is connected to the liquid hydrogen gasification system 204 through a liquid hydrogen delivery pipeline 214.

[0096] Specifically, the LNG supply system 101 is configured to deliver liquefied natural gas to the water electrolysis hydrogen production system 201.

[0097] The water electrolysis hydrogen production system 201 is configured to produce hydrogen by using a water electrolysis hydrogen production technology.

[0098] The hydrogen liquefaction system 202 is configured to liquefy hydrogen by using cold energy to obtain liquid hydrogen.

[0099] The liquid hydrogen storage system 203 is configured to store liquid hydrogen at normal pressure or slightly positive pressure.

[0100] The liquid hydrogen gasification system 204 is configured to gasify liquid hydrogen to obtain hydrogen.

[0101] In a specific embodiment, referring to Figure 1 , the hydrogen production system further includes a cold energy air separation system 301.

[0102] Specifically, the cold energy extraction and storage system 104 is connected with the cold energy air separation system 301 through the fifth and sixth cold carrier circulating pipelines 311 and 312, and the cold energy air separation system 301 is connected with the hydrogen liquefaction system 202 through the first and second liquid nitrogen circulating pipelines 231 and 232.

[0103] Specifically, the cold energy extraction and storage system 104 is used to extract and store cold energy released in the liquefied natural gas gasification process in different temperature zones; the cold extraction zone of the cold energy extraction and storage system 104 can include a first temperature zone; optionally, the first temperature zone can be -160℃-155℃.

[0104] The cold energy air separation system 301 mainly uses 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, and the temperature of the liquid nitrogen product is -210℃-196℃ (in Celsius).

[0105] The hydrogen liquefaction system 202 is used to liquefy hydrogen to obtain liquid hydrogen by using the cold energy in the first temperature zone and the liquid nitrogen.

[0106] In this embodiment, the main cold extraction zone of the cold energy extraction and storage system 104 is mainly -160℃-155℃, and the main destination of the cold energy is the second stage pre-cooling of the hydrogen liquefaction system 202 and the cooling of the circulating nitrogen of the cold energy air separation system 301.

[0107] The electrolytic water hydrogen production system 201 delivers the produced hydrogen to the hydrogen liquefaction system 202 through the hydrogen delivery pipeline 211.

[0108] The hydrogen liquefaction system 202 is connected with the cold energy extraction and storage system 104 through the third and fourth cold carrier circulating pipelines 121 and 122, and connected with the cold energy air separation system 301 through the first and second liquid nitrogen circulating pipelines 231 and 232, and the hydrogen liquefaction system 202 uses the cold energy provided by the cold energy extraction and storage system 104 and the cold energy air separation system 301 to liquefy the hydrogen obtained by the electrolytic water hydrogen production system 201 to obtain liquid hydrogen, and the liquefaction process includes primary- secondary conversion.

[0109] In the hydrogen liquefaction process, different grades of cold energy of the cold energy extraction and storage system 104 can be used to achieve the target liquefaction temperature at different liquefaction stages.

[0110] The liquid hydrogen storage system 203 is connected with the hydrogen liquefaction system 202 through the liquid hydrogen delivery pipeline 212, and the liquid hydrogen storage system 203 is used to store liquid hydrogen at normal pressure or slightly positive pressure, and the storage pressure is 0.1-0.5 MPag.

[0111] The liquid hydrogen gasification system 204 is connected with the liquid hydrogen storage system 203 through a liquid hydrogen delivery pipeline 214, and is used to gasify the liquid hydrogen to obtain hydrogen gas when there is a hydrogen delivery demand downstream.

[0112] In another specific embodiment, referring to Figure 2 , the hydrogen production system further comprises a cold energy utilization system 302.

[0113] The cold energy extraction and storage system 104 is connected with the cold energy utilization system 302 through a fifth carrier refrigerant circulation pipeline 311 and a sixth carrier refrigerant circulation pipeline 312.

[0114] The cold energy extraction and storage system 104 is used to extract and store cold energy released in the liquefied natural gas gasification process in different temperature zones. The cold extraction zone of the cold energy extraction and 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℃.

[0115] Optionally, the cold energy utilization system 302 is used to utilize the cold energy in the first temperature zone, the second temperature zone and the third temperature zone in stages.

[0116] Specifically, the cold energy utilization system 302 is connected with the cold energy extraction and storage system 104 through the fifth carrier refrigerant circulation pipeline 311 and the sixth carrier refrigerant circulation pipeline 312, to extract and utilize the cold energy stored in the cold energy extraction and storage system 104. The cold energy utilization system 302 utilizes the cold energy of different grades in the cold energy extraction and storage system 104 in stages, 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, 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 liquefy hydrogen into liquid hydrogen by utilizing the cold energy in the first temperature zone and liquid nitrogen.

[0117] In this embodiment, the main cold extraction zone of the cold energy extraction and storage system 104 is mainly -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.

[0118] The electrolytic water hydrogen production system 201 delivers the produced hydrogen to the hydrogen liquefaction system 202 through a hydrogen delivery pipeline 211.

[0119] The hydrogen liquefaction system 202 is connected to the cold energy harvesting system 104 through the third and fourth coolant circulation pipelines 121 and 122, and the hydrogen liquefaction system 202 uses the cold energy provided by the cold energy harvesting system 104 to liquefy the hydrogen obtained by the electrolytic water hydrogen production system 201 to obtain liquid hydrogen, and the liquefaction process includes primary- secondary conversion.

[0120] During the hydrogen liquefaction process, different cold energy of different grades provided by the cold energy harvesting system 104 can be used to achieve the target liquefaction temperature at different stages of the liquefaction process.

[0121] The liquid hydrogen storage system 203 is connected to the hydrogen liquefaction system 202 through the liquid hydrogen delivery pipeline 212, and the liquid hydrogen storage system 203 is used to store the liquid hydrogen at normal pressure or slightly positive pressure, and the storage pressure is 0.1-0.5 MPag.

[0122] The liquid hydrogen gasification system 204 is connected to the liquid hydrogen storage system 203 through the liquid hydrogen delivery pipeline 214, and is used to gasify the liquid hydrogen to obtain hydrogen gas when there is a demand for hydrogen delivery downstream.

[0123] In some embodiments, referring to Figure 2 , the liquid hydrogen gasification system 204 is connected to the cold energy harvesting system 104 through the seventh and eighth coolant circulation pipelines 241 and 242, and is used to collect the cold energy during the liquid hydrogen gasification process and deliver it to the cold energy harvesting system 104 for cold energy utilization and hydrogen liquefaction. The connection relationship between the liquid hydrogen gasification system 204 and the cold energy harvesting system 104 is also applicable to the liquid hydrogen gasification system 204 and the cold energy harvesting system 104 in Figure 1 , and in the example of Figure 1 , the liquid hydrogen gasification system 204 can also be connected to the cold energy harvesting system 104 through the seventh and eighth coolant circulation pipelines 241 and 242, and the connection relationship between the liquid hydrogen gasification system 204 and the cold energy harvesting system 104 is not shown in Figure 1

[0124] In some embodiments, referring to Figure 1 and Figure 2 , the hydrogen production system further includes a blending control valve 119 and a natural gas hydrogen blending system 205;

[0125] The LNG cold energy power generation system 421 and the LNG gasification system 103 are both connected to the natural gas delivery pipeline 115, and the natural gas delivery pipeline 115 is connected to the blending control valve 119;

[0126] The blending control valve 119 is connected to the natural gas hydrogen blending system 205 through the natural gas delivery bypass pipeline 116;

[0127] The liquid hydrogen gasification system 204 is connected to the natural gas hydrogen blending system 205 through the hydrogen pipeline 215. ​

[0128] Specifically, the LNG cold energy power generation system 421 is further configured to input the natural gas obtained by gasifying the liquefied natural gas into the natural gas transmission pipeline 115. The LNG gasification system 103 inputs the natural gas obtained by gasification into the natural gas transmission pipeline 115.

[0129] The natural gas transmission pipeline 115 is connected with the blending control valve 119 and the natural gas transmission metering system 106, respectively.

[0130] The blending control valve 119 is connected with the natural gas hydrogen blending system 205 through the natural gas transmission bypass pipeline 116; the liquid hydrogen gasification system 204 is connected with the natural gas hydrogen blending system 205 through the hydrogen pipeline 215, and the natural gas hydrogen blending system 205 is connected with the hydrogen blending transmission metering system 206 through the hydrogen blending transmission pipeline 216.

[0131] Specifically, the blending control valve is configured to receive a control signal and perform a closing operation.

[0132] If the blending control valve receives a blending control signal, the closing operation is performed, and the natural gas hydrogen blending system 205 mixes the natural gas and the hydrogen gas according to a preset ratio and then outputs the mixed gas to the outside through the hydrogen blending transmission pipeline 216 and the hydrogen blending transmission metering system 206.

[0133] Optionally, the blending ratio of the natural gas hydrogen blending transmission ranges from 3% to 10%, that is, the ratio of the hydrogen gas to the mixed gas is not less than 3% and not more than 10%; wherein the mixed gas includes the hydrogen gas and the natural gas.

[0134] In this embodiment, whether to blend and transmit and the blending ratio can be determined by controlling the opening and closing of the blending control valve 119.

[0135] If the blending control valve receives a separation control signal, the closing operation is performed, and the natural gas and the hydrogen gas are not mixed, but are transmitted to the outside separately. The natural gas is output to the outside through the natural gas transmission pipeline 115 and the natural gas transmission metering system 106, and the hydrogen gas is output to the outside through the natural gas hydrogen blending system 205, the hydrogen blending transmission pipeline 216 and the hydrogen blending transmission metering system 206.

[0136] 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 and includes the following steps.

[0137] S100: The station micro-grid supplies power to the station process system; wherein the station process system includes a natural gas production system and a hydrogen production system.

[0138] S200: The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released in the gasification process;

[0139] S300: The hydrogen production system produces hydrogen, and liquefies and stores the produced hydrogen by using the stored cold energy; in the case that there is a hydrogen output demand downstream, the stored liquid hydrogen is gasified to obtain hydrogen.

[0140] The cogeneration process method provided by the embodiments of the present application can realize process coupling of LNG gasification, cold energy storage, hydrogen production, liquefaction, storage, and gasification, realize fusion of normal production of an LNG receiving station and the whole process of hydrogen production, storage, and transportation, can fully and deeply integrate an LNG industry chain and a hydrogen energy industry chain, realize efficient utilization of energy and comprehensive supply of energy, and promote infrastructure co-construction and sharing in energy transformation.

[0141] Optionally, the natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and stores the cold energy released in the gasification process, and specifically includes:

[0142] The natural gas production system gasifies the received liquefied natural gas to obtain natural gas, and extracts and stores the cold energy released in the gasification process in different temperature zones;

[0143] In the case that the hydrogen production system includes the cold energy air separation system, the cold energy extraction interval includes the first temperature zone;

[0144] In the case that the hydrogen production system includes the cold energy utilization system, the cold energy extraction interval includes the first temperature zone, the second temperature zone, and the third temperature zone.

[0145] Optionally, the produced hydrogen is liquefied by using the stored cold energy, and specifically includes: in the case that the hydrogen production system includes the cold energy air separation system, the cold energy in the first temperature zone is used to separate air to obtain liquid nitrogen, and the cold energy in the first temperature zone and the liquid nitrogen are used to liquefy hydrogen to obtain liquid hydrogen.

[0146] In the case that the hydrogen production system includes the cold energy utilization system, the cold energy in the first temperature zone, the second temperature zone, and the third temperature zone is used in stages, and the cold energy in the first temperature zone is used to liquefy hydrogen to obtain liquid hydrogen.

[0147] In some embodiments, the hydrogen production system further includes a blending control valve and a natural gas hydrogen blending system; the method further includes:

[0148] If the blending control valve receives a blending control signal, the blending control valve performs a closing operation;

[0149] The natural gas hydrogen blending system mixes natural gas and hydrogen according to a preset ratio, and then outputs the mixed natural gas and hydrogen to the outside through a hydrogen-blended output pipeline and a hydrogen-blended output metering system;

[0150] The ratio of hydrogen to mixed gas is not less than 3% and not more than 10%; the mixed gas includes hydrogen and natural gas.

[0151] If the blending control valve receives the 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 hydrogen blending system, the hydrogen blending transmission pipeline, and the hydrogen blending transmission metering system 206.

[0152] The above embodiments are merely exemplary embodiments of the present application and are not intended to limit the scope of the present application. The scope of protection 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 scope of protection of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the present application.

Claims

1. A co-production process system, characterized in that: For providing 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; wherein the on-site microgrid comprises an LNG cold energy power generation system; The process system within 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; wherein the natural gas production system includes an LNG gasification system and a cold energy storage system; The hydrogen production system is connected to the natural gas production system, and is used to produce hydrogen and utilize the stored cold energy to liquefy, store and gasify the produced hydrogen; wherein the hydrogen production system includes a water electrolysis hydrogen production system, a hydrogen liquefaction system, a liquid hydrogen storage system, a liquid hydrogen gasification system, a cold energy utilization system, a blending control valve and a natural gas hydrogen blending system; The water electrolysis hydrogen production system is connected to the hydrogen liquefaction system through a hydrogen delivery pipeline; The cold energy storage system is connected to the hydrogen liquefaction system via 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; The cold energy storage system is connected to the cold energy utilization system via a fifth coolant circulation pipe and a sixth coolant circulation pipe; 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, 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 liquefy hydrogen to obtain liquid hydrogen using the cold energy in the first temperature zone; The liquid hydrogen gasification system is connected to the cold energy storage system via a seventh coolant circulation pipeline and an eighth coolant circulation pipeline; 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.

2. The system according to claim 1, wherein: The in-station microgrid also includes 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 via 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 via the station power grid, and is used to generate new energy using the new energy raw materials in the station; The on-site energy storage system is connected to the on-site process system via the on-site 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 on-site process system; The power grid control system is used to control the storage and supply of electric energy of the in-station energy storage system.

3. The system according to claim 2, characterized in that The LNG supply system is connected to the LNG gasification system via 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 1, wherein: 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 via a fifth refrigerant circulation pipeline and a sixth refrigerant circulation pipeline, and the cold energy air separation system is connected to the hydrogen liquefaction system via a first liquid nitrogen circulation pipeline and a 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's cold energy extraction interval 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.

5. A co-production process, characterized in that: Applied to the co-production process system according to any one of claims 1 to 4, the method comprises: The microgrid on the station supplies power to the process systems on the station; wherein the process systems on the station include 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.

6. The method according to claim 5, characterized in that 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.

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