Oil and gas field produced water hydrogen production system

Abstract

The utility model discloses an oil-gas field produced water hydrogen production system. The device comprises a water treatment module, a steam supply module, a metal cracking steam hydrogen production module and an auxiliary module, the produced water is treated by the water treatment module to obtain clear water, and the clear water enters the steam supply module; dry saturated steam generated after clear water passes through the steam supply module enters the metal cracking steam hydrogen production module; the dry saturated steam is subjected to cracking reaction and condensation heat exchange through the metal cracking water vapor hydrogen production module, and purified hydrogen is output through a conveying system. The method has the beneficial effects that on-site treatment and recycling of the produced water are realized under the condition that a produced water treatment station is not built; stratum and natural ecology cannot be damaged, pollution to the environment is avoided, and the requirements of safe and environment-friendly exploration and development are met.

Description

Technical Field

[0001] The utility model relates to an oil and gas field produced water treatment system, in particular to an oil and gas field produced water hydrogen production system, belonging to the technical field of oil and gas exploration and development. Background Art

[0002] A large amount of produced water is generated during the development of oil fields. Most of the produced water is reinjected after treatment to balance formation pressure and flood oil. However, some blocks still cannot reinject produced water due to the lack of effective oil and water treatment capabilities. In particular, the associated water generated during the exploitation of coalbed methane and natural gas has a relatively small water production volume, and the well site supporting facilities are not perfect, so it is not appropriate to invest in the construction of treatment stations.

[0003] For these wastewaters, oil and gas fields usually adopt the following three methods:

[0004] First, water treatment stations are built using the process of adding chemicals, multi-stage sedimentation, oil removal, and multi-stage filtration to make the produced water meet the requirements of formation reinjection, and to carry out same-layer reinjection or invalid reinjection; this water treatment process is complex, with many types of equipment and a large footprint; the amount of chemical agents used is large, the comprehensive treatment cost is high, and the investment in the treatment station is large;

[0005] Second, if there are no conditions for building a station, the produced water will be transported to other treatment stations or local water treatment plants for treatment; this method will increase transportation costs and entrusted water treatment costs;

[0006] Third, for individual blocks that do not meet the above conditions, the only options are natural evaporation or direct ineffective reinjection without treatment, which will seriously affect the natural ecology, damage the strata, and pollute the environment. Utility Model Content

[0007] In order to overcome the above-mentioned deficiencies in the existing produced water treatment technology for oil and gas development, the utility model provides an oil and gas field produced water hydrogen production system.

[0008] The utility model solves the technical problem by adopting a technical solution: an oil and gas field produced water hydrogen production system, comprising a water treatment module, a steam supply module, a metal cracking water steam hydrogen production module, and an auxiliary module.

[0009] The clean water obtained after the produced water is treated by the water treatment module enters the steam supply module; the dry saturated steam generated after the clean water passes through the steam supply module enters the metal cracking water vapor hydrogen production module; the dry saturated steam undergoes cracking reaction, condensation heat exchange, and purified hydrogen in the metal cracking water vapor hydrogen production module and is output through the transportation system.

[0010] The water treatment module comprises a water treatment device, a fine filtering device and a clean water tank which are connected in sequence.

[0011] The products of produced water after being treated by the water treatment device include oil, dirt and clean water. The oil is transported to the oil tank through the oil pipeline, the dirt is discharged into the sewage pool through the sewage pipe at the bottom of the water treatment device, and the clean water enters the steam supply module.

[0012] A buffer water tank with pressure and flow stabilization functions is installed in series between the water treatment device and the fine filtering device.

[0013] When the produced water has a high salinity, the hydrogen production system is provided with a multi-effect crystallization module.

[0014] The steam supply module is connected to the multiple-effect crystallization module to provide required steam to the multiple-effect crystallization module.

[0015] The low-temperature evaporation device and the steam supply device of the steam supply module are connected in sequence, and the product of the clean water after passing through the low-temperature evaporation device and the steam supply device in sequence is dry saturated steam or includes dry saturated steam and bottom concentrated liquid, wherein the dry saturated steam enters the metal cracking water vapor hydrogen production module, and the bottom concentrated liquid enters the multi-effect crystallization module.

[0016] The metal cracking water vapor hydrogen production module comprises a cracking reaction device and a condensation heat exchange device which are connected in sequence.

[0017] The dry saturated steam generated by the steam supply module enters the cracking reaction device. After being processed by the cracking reaction device, the dry saturated steam generates water-containing hydrogen and condensed water. The water-containing hydrogen enters the condensation heat exchange device, and the condensed water is returned to the clean water tank of the water treatment module through the water pipeline.

[0018] The water vapor hydrogen production module also includes a transfer tank and a purification device, and a cracking reaction device, a condensation heat exchange device, a transfer tank, and a purification device are connected in sequence.

[0019] The water-containing hydrogen passes through the condensation heat exchange device to cool and separate the water vapor in the hydrogen, and the hydrogen enters the transfer tank for pressure and flow stabilization, and then passes through the purification device to obtain hydrogen with higher purity, and the hydrogen is output through the transportation system.

[0020] A steam cylinder II having a pressure and flow stabilizing function is installed in series between the steam supply device and the cracking reaction device.

[0021] The multiple-effect crystallization module comprises a multiple-effect evaporation crystallization device and a condensation device.

[0022] The gas produced by the steam supply device of the steam supply module enters the evaporator.

[0023] The bottom concentrated liquid produced by the low-temperature evaporation device and the steam supply device is converted into gas and liquid after passing through the evaporator of the multi-effect evaporation crystallization device. The gas enters the condensation device for condensation and is then discharged; the liquid is discharged from the lower end of the evaporator into the crystallization tank and is then discharged after crystallization.

[0024] A steam cylinder I with a pressure and flow stabilizing function is installed in series between the steam supply device and the multi-effect evaporation crystallization device.

[0025] The auxiliary module includes an electrical control device for controlling the hydrogen production system and a nitrogen replacement device for ensuring the safe operation of the hydrogen production system.

[0026] The hydrogen production system adopts a modular skid-mounted structure that is easy to transport and can be quickly disassembled and installed.

[0027] The beneficial effects of the utility model are: reasonable design, on-site treatment and recycling of produced water can be achieved without the need to build a produced water treatment station, reducing transportation costs and entrusted treatment costs; modular design is adopted, the well site is reasonably utilized, the footprint is small, and it is easy to transport, disassemble and install; the amount of chemical agents used is small, effectively reducing the comprehensive treatment cost; it will not damage the stratum and natural ecology, avoid pollution to the environment, and meet the requirements of safe and environmentally friendly exploration and development. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of a system for producing hydrogen from produced water in oil and gas fields according to the utility model.

[0029] Figure 2 It is a structural schematic diagram of the utility model of the oil and gas field produced water hydrogen production system.

[0030] In the figure: 1. Water treatment module, 2. Steam supply module, 3. Multi-effect crystallization module, 4. Metal cracking water vapor hydrogen production module, 5. Auxiliary module, 11. Water treatment device, 12. Buffer water tank, 13. Fine filtration device, 14. Clean water tank, 21. Steam supply device, 22. Bottom concentrate pipeline, 23. Heat exchanger, 24. Low-temperature evaporation device, 31. Multi-effect evaporation crystallization device, 32. Separation cylinder I, 33. Condensation device, 41. Separation cylinder II, 42. Cracking reaction device, 43. Transfer tank, 44. Purification device, 45. Condensation heat exchange device, 51. Nitrogen replacement device, 52. Electrical control device, 311. Evaporator, 312. Crystallization tank. DETAILED DESCRIPTION

[0031] The utility model is further described below in conjunction with the accompanying drawings and embodiments. However, those skilled in the art should be aware that the present invention is not limited to the specific embodiments listed, and all embodiments should be included in the protection scope of the present invention as long as they conform to the spirit of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "left", "right", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing or simplifying the description of the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection, a direct connection, an indirect connection, or an integral connection; it can be a mechanical connection, an indirect connection through an intermediate medium, or a connection between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] See attached Figure 1 A system for producing hydrogen from produced water in oil and gas fields comprises a water treatment module 1, a steam supply module 2, a multi-effect crystallization module 3, a metal cracking water vapor hydrogen production module 4 and an auxiliary module 5.

[0035] The clean water obtained after the produced water is treated by the water treatment module 1 enters the steam supply module 2; the dry saturated steam generated after the clean water passes through the steam supply module 2 enters the metal cracking water vapor hydrogen production module 4; the dry saturated steam undergoes cracking reaction, condensation heat exchange, and purified hydrogen in the metal cracking water vapor hydrogen production module 4 and is output through the transportation system.

[0036] See attached Figure 2 The water treatment module 1 comprises a water treatment device 11, a fine filtering device 13, and a clean water tank 14 which are connected in sequence.

[0037] The products of produced water after being treated by the water treatment device 11 include oil, dirt and clean water. The oil is transported to the oil tank through the oil pipeline, the dirt is discharged into the sewage pool through the sewage pipe at the bottom of the water treatment device 11, and the clean water enters the steam supply module 2.

[0038] Preferably, the water treatment device 11 uses graphene processing equipment or high frequency / electromagnetic pulse processing equipment. The fine filtering device 13 uses a filter material filter or a membrane filter, such as sand filter, walnut shell, anthracite, etc., and can also use a membrane filter to further filter the water treated by the water treatment device 11 to obtain clean water with higher water quality.

[0039] Preferably, a buffer water tank 12 with a pressure and flow stabilizing function is installed in series between the water treatment device 11 and the fine filtering device 13. After the water obtained by the water treatment device 11 passes through the buffer water tank 12 for pressure and flow stabilization, the liquid flow becomes more stable.

[0040] When the produced water has a high mineralization, the hydrogen production system is provided with a multi-effect crystallization module 3 to process the bottom concentrate discharged from the steam supply module 2. The steam supply module 2 is connected to the multi-effect crystallization module 3 to provide the multi-effect crystallization module 3 with the required steam.

[0041] The low-temperature evaporation device 24 and the steam supply device 21 of the steam supply module 2 are connected in sequence, and the product of the clean water after passing through the low-temperature evaporation device 24 and the steam supply device 21 in sequence is dry saturated steam or includes dry saturated steam and bottom concentrated liquid, wherein the dry saturated steam enters the metal cracking water vapor hydrogen production module 4, and the bottom concentrated liquid enters the multi-effect crystallization module 3. Preferably, the steam supply device 21 is a steam boiler or a steam generator.

[0042] The metal cracking steam hydrogen production module 4 comprises a cracking reaction device 42 and a condensing heat exchange device 45 which are connected in sequence.

[0043] The dry saturated steam generated by the steam supply module 2 enters the cracking reaction device 42. After being processed by the cracking reaction device 42, the dry saturated steam generates hydrogen containing a small amount of water vapor and condensed water. The hydrogen containing a small amount of water vapor enters the condensation heat exchange device 45, and the condensed water is returned to the clean water tank 14 of the water treatment module 1 through the water pipeline.

[0044] The water vapor hydrogen production module 4 also includes a transfer tank 43 and a purification device 44. The cracking reaction device 42, the condensation heat exchange device 45, the transfer tank 43, and the purification device 44 are connected in sequence; the water-containing hydrogen passes through the condensation heat exchange device 45 to cool and separate the water vapor in the hydrogen, and the hydrogen enters the transfer tank 43 for pressure and flow stabilization, and then passes through the purification device 44 to obtain hydrogen with higher purity, and the hydrogen is output through the transportation system.

[0045] A steam cylinder II 41 having a pressure and flow stabilizing function is installed in series between the steam supply device 21 and the cracking reaction device 42 .

[0046] Specifically, a cracking agent is provided in the reaction tank of the cracking reaction device 42, in which dry saturated steam is cracked to generate hydrogen, and the water vapor in the hydrogen is preliminarily cooled and separated by the condensing heat exchange device II45, and the hydrogen enters the transfer tank 43 through the pipeline. After the pressure and flow are stabilized by the transfer tank 43, the hydrogen enters the purification device II44, and the hydrogen is further purified to reduce the water vapor content in the hydrogen, and finally high-purity hydrogen is obtained, and the hydrogen is output through the transportation system.

[0047] The multiple-effect crystallization module 3 includes a multiple-effect evaporation crystallization device 31 and a condensation device 33 .

[0048] According to on-site needs, part of the gas produced by the steam supply device 21 of the steam supply module 2 enters the evaporator 311 .

[0049] The bottom concentrated liquid produced by the low-temperature evaporation device 24 and the steam supply device 21 is converted into gas and concentrated liquid after passing through the evaporator 311 of the multi-effect evaporation crystallization device 31. The gas enters the condensation device 33 and is condensed before being discharged; the concentrated liquid is discharged from the lower end of the evaporator 311 and enters the crystallization tank 312, and is discharged after crystallization. Preferably, the crystallized salt is initially crystallized and then handed over to a relevant processing plant for fine screening.

[0050] A steam cylinder I 32 with a stabilizing pressure and flow function is installed in series between the steam supply device 21 and the multi-effect evaporation crystallization device 31. Preferably, one end of the steam cylinder I 32 is connected to the steam output pipeline of the steam boiler or steam generator 21, and the other end is connected to the inlet of the evaporator 311.

[0051] The auxiliary module 5 includes an electrical control device 52 for controlling the hydrogen production system and a nitrogen replacement device 51 for ensuring the safe operation of the hydrogen production system.

[0052] The nitrogen replacement device 51 is used to replace the oxygen in the steam supply module 2, the multi-effect crystallization module 3, the metal cracking water vapor hydrogen production module 4 and the hydrogen production system pipeline with nitrogen. Usually, before the hydrogen production system is operated, the nitrogen replacement device 51 replaces the steam supply module 2, the multi-effect crystallization module 3, the metal cracking water vapor hydrogen production module 4 and the system pipeline with nitrogen to ensure safe operation.

[0053] The hydrogen production system adopts a modular skid-mounted structure that is convenient for transportation and quick disassembly and installation. Preferably, the modules of the hydrogen production system are divided according to their functions, that is, the water treatment module 1, the steam supply module 2, the multi-effect crystallization module 3, the metal cracking water vapor hydrogen production module 4 and the auxiliary module 5 are each installed on one or more skids to facilitate transportation and quick disassembly and installation.

[0054] The hydrogen production system can set the number of various devices in each module according to the amount of water produced at the production site and its hydrogen production demand, and install similar devices in the module in series or in parallel according to process requirements, so as to fully and effectively utilize resources for hydrogen production.

[0055] Embodiment 1:

[0056] The oil and gas field produced water hydrogen production system of the present invention is applied to the ×× condensate gas field of the ×× oil field. The produced water salinity of this block is 40179 mg / L, which is high-salinity produced water.

[0057] As attached Figure 1 , 2 As shown, the produced water hydrogen production system includes a water treatment module 1, a steam supply module 2, a multi-effect crystallization module 3, a metal cracking water vapor hydrogen production module 4, and an auxiliary module 5.

[0058] The water treatment module 1 , the steam supply module 2 , and the metal cracking steam hydrogen production module 4 are connected in sequence; the bottom concentrated liquid outlet of the steam supply module 2 is connected to the multi-effect crystallization module 3 .

[0059] The electrical control device 52 of the auxiliary module 5 is used to control the operation of the hydrogen production system; the nitrogen replacement device 51 replaces the oxygen in the steam supply module 2, the multi-effect crystallization module 3, the metal cracking water vapor hydrogen production module 4 and the hydrogen production system pipeline with nitrogen when necessary to ensure the safe operation of the hydrogen production system.

[0060] The water treatment device 11, the buffer water tank 12, the fine filtering device 13, and the clean water tank 14 of the water treatment module 1 are connected in sequence.

[0061] The products of produced water after being treated by the water treatment device 11 include oil, dirt and clean water. The oil is transported to the oil tank through the oil pipeline, the dirt is discharged into the sewage pool through the sewage pipe at the bottom of the water treatment device 11, and the clean water enters the steam supply module 2.

[0062] The water treatment device 11 adopts a graphene treatment device. The water obtained after being treated by the water treatment device 11 passes through a buffer water tank 12 for pressure and flow stabilization and then enters a fine filtering device 13 .

[0063] The fine filtering device 13 uses a filter material filter, and the filter material uses sand filter, walnut shell, and anthracite to further filter the water treated by the water treatment device 11 to obtain clean water with higher water quality.

[0064] Since the produced water in this block has a high mineralization, the hydrogen production system is provided with a multi-effect crystallization module 3 , which is connected to the steam supply module 2 to process the bottom concentrated liquid discharged from the steam supply module 2 .

[0065] The steam supply module 2 includes a low-temperature evaporation device 24 and a steam supply device 21, wherein the steam supply device 21 is a steam boiler. Clean water first enters the low-temperature evaporation device 24, and then the outlet steam generates condensed water under normal pressure, which enters the steam boiler. The product of the condensed water after passing through the steam boiler is dry saturated steam, which enters the metal cracking water vapor hydrogen production module 4. For high-mineralization produced water, the bottom concentrate produced in the low-temperature evaporation device 24 and the steam boiler enters the multi-effect crystallization module 3.

[0066] The steam cylinder II 41, the cracking reaction device 42, the transfer tank 43 and the purification device 44 of the metal cracking steam hydrogen production module 4 are connected in sequence.

[0067] The dry saturated steam generated by the steam supply module 2 enters the cracking reaction device 42. The reaction tank of the cracking reaction device 42 is provided with a cracking agent. The dry saturated steam is cracked to generate hydrogen and condensed water. The hydrogen is initially cooled and separated from the water vapor through the condensation heat exchange device 45, and the hydrogen is collected into the transfer tank 43 through a pipeline. After the hydrogen passes through the transfer tank 43 for pressure and flow stabilization, it enters the purification device 44 to further separate the condensed water to reduce the water vapor content in the hydrogen. Finally, the hydrogen with higher purity is obtained, and the hydrogen is output through the transportation system; the condensed water is returned to the clean water tank 14 of the water treatment module 1 through the water pipeline.

[0068] The multi-effect crystallization module 3 includes a steam cylinder Ⅰ 32 , a multi-effect evaporation crystallization device 31 , and a condensation device 33 . The crystallization tank 312 of the multi-effect evaporation crystallization device 31 is arranged below the evaporator 311 , and the gas outlet arranged at the upper end of the evaporator 311 is connected to the condensation device 33 .

[0069] One end of the steam cylinder Ⅰ32 is connected to the gas output pipeline of the steam boiler, and the other end is connected to the inlet of the evaporator 311. Part of the steam produced by the steam boiler of the steam supply module 2 enters the evaporator 311 after stabilizing the flow and pressure through the steam cylinder Ⅰ32 to provide the water vapor required for crystallization.

[0070] The lower end of the low-temperature evaporation device 21 and the steam boiler is connected to the evaporator 311 through a bottom concentrated liquid pipeline 22, and the bottom concentrated liquid pipeline 22 is provided with a heat exchanger 23 for heating the bottom concentrated liquid.

[0071] The bottom concentrated liquid produced by the low-temperature evaporation device 21 and the steam boiler is heated by the heat exchanger 23 and then enters the evaporator 311 of the multi-effect evaporation crystallization device 31 to generate gas and liquid. The gas enters the condensation device 33 and is condensed and then discharged; the liquid is discharged from the lower end of the evaporator 311 and enters the crystallization tank 312. After preliminary crystallization and precipitation of crystalline salt, it is handed over to the relevant processing plant for fine screening.

[0072] The hydrogen production system adopts a skid-mounted structure, and the water treatment module 1, the steam supply module 2, the multi-effect crystallization module 3, the metal cracking water vapor hydrogen production module 4 and the auxiliary module 5 are installed on multiple separate skids, which is convenient for transportation and rapid disassembly and installation.

[0073] Embodiment 2:

[0074] The oil and gas field produced water hydrogen production system of the present invention is applied to the ×× block of the ×× oil field. The produced water salinity of the block is 3039 mg / L, which is low-salinity produced water.

[0075] The produced water hydrogen production system includes a water treatment module 1, a steam supply module 2, a metal cracking water vapor hydrogen production module 4, and an auxiliary module 5.

[0076] The water treatment module 1, the steam supply module 2, and the metal cracking water vapor hydrogen production module 4 are connected in sequence.

[0077] The electrical control device 52 of the auxiliary module 5 is used to control the operation of the hydrogen production system; the nitrogen replacement device 51 replaces the oxygen in the steam supply module 2, the metal cracking water vapor hydrogen production module 4 and the hydrogen production system pipeline with nitrogen when necessary to ensure the safe operation of the hydrogen production system.

[0078] The water treatment device 11, the buffer water tank 12, the fine filtering device 13, and the clean water tank 14 of the water treatment module 1 are connected in sequence.

[0079] The products of produced water after being treated by the water treatment device 11 include oil, dirt and clean water. The oil is transported to the oil tank through the oil pipeline, the dirt is discharged into the sewage pool through the sewage pipe at the bottom of the water treatment device 11, and the clean water enters the steam supply module 2.

[0080] The water treatment device 11 adopts high frequency / electromagnetic pulse treatment equipment. The water obtained after being treated by the water treatment device 11 passes through the buffer water tank 12 for pressure and flow stabilization and then enters the fine filtering device 13.

[0081] The fine filtering device 13 uses a membrane filter to further filter the water treated by the water treatment device 11 to obtain clean water.

[0082] The steam supply module 2 includes a low-temperature evaporation device 24 and a steam supply device 21, wherein the steam supply device 21 is a steam generator. Clean water first enters the low-temperature evaporation device 24, and then the outlet steam generates condensed water under normal pressure, and the condensed water enters the steam generator. The product of the condensed water after passing through the steam generator is dry saturated steam, and the dry saturated steam enters the metal cracking water vapor hydrogen production module 4.

[0083] The steam cylinder II 41, the cracking reaction device 42, the condensation heat exchange device II 45, the transfer tank 43, and the purification device 44 of the metal cracking steam hydrogen production module 4 are connected in sequence.

[0084] The dry saturated steam generated by the steam supply module 2 enters the cracking reaction device 42, and the cracking agent is set in the reaction tank of the cracking reaction device 42. The dry saturated steam is cracked to generate hydrogen and condensed water. The hydrogen is initially cooled and separated by the wind-water cooling condensation heat exchange device II45, and the hydrogen is collected into the transfer tank 43 through the pipeline. After the hydrogen passes through the transfer tank 43 and stabilizes the pressure and flow, it enters the purification device 44 to further separate the condensed water to reduce the water vapor content in the hydrogen. Finally, the obtained hydrogen with higher purity is output through the transportation system; the condensed water is returned to the clean water tank 14 of the water treatment module 1 through the water pipeline.

[0085] The utility model of the produced water hydrogen production system for oil and gas fields utilizes the resource conditions of waste water and waste heat in oil and gas fields, and achieves hydrogen production after effective treatment of produced water through integrated and modular design. The produced water can be used for hydrogen blending and external transportation of natural gas and coalbed methane, or for boiler blending and combustion for oil field heating systems, saving natural gas consumption and reducing carbon emissions, while maximizing water resource utilization, economic benefits, and environmental protection. The integrated design of the hydrogen production system realizes the comprehensive utilization of block resources; the modular design can meet the use requirements of different block working conditions, and can increase or reduce modules according to special working conditions, effectively solving the problems of complex produced water treatment process, high treatment cost, large investment, and environmental pollution, and minimizing the environmental protection risks of oil and gas field stations.

[0086] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the claims of this patent.

Claims

1. A system for producing hydrogen from produced water in oil and gas fields, characterized by: It includes water treatment module, steam supply module, metal cracking steam hydrogen production module and auxiliary module; The clean water obtained after the produced water is treated by the water treatment module enters the steam supply module; the dry saturated steam generated after the clean water passes through the steam supply module enters the metal cracking water vapor hydrogen production module; the dry saturated steam undergoes cracking reaction, condensation heat exchange, and purified hydrogen in the metal cracking water vapor hydrogen production module and is output through the transportation system.

2. The oil and gas field produced water hydrogen production system according to claim 1, characterized in that: The water treatment module comprises a water treatment device, a fine filtering device and a clean water tank which are connected in sequence.

3. The oil and gas field produced water hydrogen production system according to claim 2, characterized in that: The products of produced water after being treated by the water treatment device include oil, dirt and clean water. The oil is transported to the oil tank through the oil pipeline, the dirt is discharged into the sewage pool through the sewage pipe at the bottom of the water treatment device, and the clean water enters the steam supply module.

4. The oil and gas field produced water hydrogen production system according to claim 3, characterized in that: A buffer water tank with a pressure and flow stabilizing function is installed in series between the water treatment device and the fine filtering device.

5. The oil and gas field produced water hydrogen production system according to claim 1, characterized in that: When the produced water has a high mineralization, the hydrogen production system is provided with a multi-effect crystallization module; The steam supply module is connected to the multiple-effect crystallization module to provide required steam to the multiple-effect crystallization module.

6. The oil and gas field produced water hydrogen production system according to claim 5, characterized in that: The low-temperature evaporation device and the steam supply device of the steam supply module are connected in sequence, and the product of the clean water after passing through the low-temperature evaporation device and the steam supply device in sequence is dry saturated steam or includes dry saturated steam and bottom concentrated liquid, wherein the dry saturated steam enters the metal cracking water vapor hydrogen production module, and the bottom concentrated liquid enters the multi-effect crystallization module.

7. The oil and gas field produced water hydrogen production system according to claim 6, characterized in that: The metal cracking water vapor hydrogen production module comprises a cracking reaction device and a condensation heat exchange device which are connected in sequence.

8. The oil and gas field produced water hydrogen production system according to claim 7, characterized in that: The dry saturated steam generated by the steam supply module enters the cracking reaction device. After being processed by the cracking reaction device, the dry saturated steam generates water-containing hydrogen and condensed water. The water-containing hydrogen enters the condensation heat exchange device, and the condensed water is returned to the clean water tank of the water treatment module through the water pipeline.

9. The oil and gas field produced water hydrogen production system according to claim 8, characterized in that: The water vapor hydrogen production module also includes a transfer tank and a purification device, and the cracking reaction device, the condensation heat exchange device, the transfer tank, and the purification device are connected in sequence; The water-containing hydrogen passes through the condensation heat exchange device to cool and separate the water vapor in the hydrogen, and the hydrogen enters the transfer tank for pressure and flow stabilization, and then passes through the purification device to obtain hydrogen with higher purity, and the hydrogen is output through the transportation system.

10. The oil and gas field produced water hydrogen production system according to claim 9, characterized in that: A steam cylinder II having a pressure and flow stabilizing function is installed in series between the steam supply device and the cracking reaction device.

11. The oil and gas field produced water hydrogen production system according to claim 6, characterized in that: The multiple-effect crystallization module includes a multiple-effect evaporation crystallization device and a condensation device; The gas produced by the steam supply device of the steam supply module enters the evaporator; The bottom concentrated liquid produced by the low-temperature evaporation device and the steam supply device is converted into gas and liquid after passing through the evaporator of the multi-effect evaporation crystallization device. The gas enters the condensation device for condensation and is then discharged; the liquid is discharged from the lower end of the evaporator into the crystallization tank and is then discharged after crystallization.

12. The oil and gas field produced water hydrogen production system according to claim 11, characterized in that: A steam cylinder I with a pressure and flow stabilizing function is installed in series between the steam supply device and the multi-effect evaporation crystallization device.

13. The oil and gas field produced water hydrogen production system according to claim 1, characterized in that: The auxiliary module includes an electrical control device for controlling the hydrogen production system and a nitrogen replacement device for ensuring the safe operation of the hydrogen production system.

14. The oil and gas field produced water hydrogen production system according to claim 1, characterized in that: The hydrogen production system adopts a modular skid-mounted structure that is easy to transport and can be quickly disassembled and installed.

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