Methane cracking hydrogen production system

Abstract

The utility model belongs to the technical field of methane hydrogen production, and particularly relates to a methane cracking hydrogen production system which comprises a molten metal reactor, the bottom of the molten metal reactor is connected with a methane inlet pipe, and the upper portion of the molten metal reactor is connected with a hydrogen discharge pipe and a carbon flow guide pipe. A buffer area, a reaction area and a hydrogen buffer area are sequentially arranged in the shell from bottom to top, the buffer area is used for conducting gas diffusion on methane to enable the methane to enter the reaction area, the methane is subjected to a high-temperature cracking reaction in the reaction area to generate hydrogen and carbon black, and the hydrogen upwards enters the hydrogen buffer area and is discharged through a hydrogen discharging pipe I; carbon black is deposited upwards at the bottom of the hydrogen buffer area, a carbon scraping device is arranged in the methane cracking system and used for pushing and sweeping the carbon black, and the carbon black enters a carbon collecting and cleaning device through a carbon flow guide pipe.

Description

Technical Field

[0001] The utility model belongs to the technical field of methane hydrogen production, and specifically relates to a methane cracking hydrogen production system. Background Art

[0002] Among the many new energy sources, hydrogen energy will become the most ideal energy in the 21st century. This is because, when burning the same weight of coal, gasoline and hydrogen, hydrogen produces the most energy, and its combustion product is water, without ash and exhaust gas, and will not pollute the environment; while coal and oil combustion produce carbon dioxide and sulfur dioxide, which can produce greenhouse effect and acid rain respectively. The reserves of coal and oil are limited, while hydrogen is mainly stored in water, and the only product after combustion is also water, which can produce hydrogen continuously and will never run out.

[0003] The development of a process for producing hydrogen and solid carbon by cracking molten metal of natural gas has always been a difficult problem in the industry. The technical route is relatively special and the research and development is difficult. It is an industry problem and a promising research direction. The current development difficulty is mainly restricted by the development of high-temperature reactors (1100°C), the development of a continuous discharge process for solid carbon from the reactor, and the development of a high-temperature hydrogen purification technology. The current existing technology for hydrogen purification and recovery uses PSA technology, which has poor recovery rate and utilization of high-temperature energy of the system and low purity. In addition, the existing carbon removal process is difficult to achieve continuous carbon removal, and the reactor is easily blocked, the purity of the removed carbon is low, the process is long, and safety cannot be guaranteed.

[0004] The above information disclosed in the above background technology section is only used to enhance the understanding of the background technology of the technology described in this article. Therefore, the background technology may contain certain information that does not form the prior art known in this country to those skilled in the art. Utility Model Content

[0005] In order to solve the defects of the above-mentioned prior art, the utility model proposes a methane cracking hydrogen production system.

[0006] The technical solution adopted by the utility model is as follows:

[0007] A methane cracking hydrogen production system comprises a molten metal reactor, wherein the bottom of the molten metal reactor is connected to a methane inlet pipe, and the upper part is connected to a hydrogen exhaust pipe and a carbon guide pipe. The molten metal reactor comprises a shell, and the interior of the shell is sequentially arranged as a buffer zone, a reaction zone and a hydrogen buffer zone from bottom to top. The buffer zone is used to diffuse methane gas so that it enters the reaction zone. Methane undergoes a high-temperature cracking reaction in the reaction zone to generate hydrogen and carbon black. The hydrogen enters the hydrogen buffer zone upward and is discharged through a hydrogen exhaust pipe I. The carbon black is deposited upward at the bottom of the hydrogen buffer zone.

[0008] The preferred technical solution also includes a carbon collection and cleaning device for processing carbon black. The carbon collection and cleaning device is connected to the methane cracking system through a carbon guide tube. The methane cracking system is provided with a carbon scraping device, which is used to push and sweep the carbon black into the carbon collection and cleaning device through the carbon guide tube.

[0009] In the preferred technical solution, the buffer zone is composed of two buffer chambers, the two buffer chambers are separated by a distributor, the upper buffer chamber and the reaction zone are separated by an air distribution pipe, and the reaction zone is composed of a molten metal layer, a molten salt layer and a carbon deposition layer from bottom to top, and a plurality of baffles are arranged in the molten salt layer.

[0010] In a preferred technical solution, the carbon deposit layer is provided with a carbon discharge port with an opening inclined downward, and the carbon guide pipe is connected to the carbon discharge port.

[0011] Furthermore, the number of the baffles is set to four, which are symmetrically distributed on both sides of the axis of the shell, arranged in a staggered and inclined manner in the vertical direction, and fixedly connected to the inner wall of the shell.

[0012] In the preferred technical solution, the shell includes an inner tube, an outer tube and a thermal insulation layer from the inside to the outside, an electric heater is installed outside the inner tube, a thermal insulation layer is provided outside the electric heater, and the inner tube is filled with metal.

[0013] In a preferred technical solution, a water cooling jacket is provided on the outer side of the shell of the hydrogen buffer zone, and cooling water is passed through the water cooling jacket to cool the hydrogen in the hydrogen buffer zone.

[0014] In the preferred technical solution, the carbon scraping device includes a first motor arranged on the top of the shell, and the rotating shaft of the first motor passes through the carbon deposit layer, the molten salt layer and the molten metal layer inward in sequence. A scraper is arranged on the rotating shaft, and the scraper is located on the surface of the carbon deposit layer. The first motor controls the scraper to rotate 180° forward and reversely. The carbon black floats on the molten salt layer to form a carbon deposit layer. After accumulating to a certain height, it is swept to the carbon discharge port by the carbon scraping device. A stirring device is also arranged in the middle of the carbon guide tube, including a second motor fixed above the carbon guide tube. The rotating shaft of the second motor penetrates into the carbon guide tube, and a stirring blade is arranged on the rotating shaft.

[0015] Furthermore, four high-temperature resistant thermocouples are installed on the rotating shaft, which are respectively located in the hydrogen buffer zone, the carbon deposition layer, the molten salt layer and the molten metal layer.

[0016] In the preferred technical solution, the carbon collection and cleaning device includes a carbon cleaning device and a carbon collection device arranged up and down, the carbon cleaning device is connected to the molten metal reactor through a carbon guide pipe, the bottom of the carbon cleaning device is connected to the carbon collection device by a pipeline, a butterfly valve is provided on the connected pipeline, the lower end of the carbon cleaning device is a cone, a cooling water flushing port is provided on the side wall of the cone, a cooling water flushing port and a hydrogen discharge port are provided on the top of the carbon cleaning device, the number of the cooling water flushing ports is two, respectively connected to a cooling water pipe, a valve is provided on the cooling water pipe, the hydrogen discharge port is connected to a hydrogen discharge pipe II, the hydrogen discharge pipe II is connected to the hydrogen discharge pipe I, the carbon black enters the carbon cleaning device and is deposited inside the cone, a liftable sealing plate is provided above the inside of the cone, a third motor for controlling the lifting of the sealing plate is provided on the top of the carbon cleaning device, and the third motor and the sealing plate are connected by a steel rope.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0018] (1) The gas distribution pipe reduces the size of bubbles generated when the gas enters the molten metal, and quickly diffuses during the rising process, fully mixing the gas and liquid and increasing the reaction interface;

[0019] (2) Four baffles are arranged in the molten metal layer 4 to increase the residence time of CH4 in the molten metal layer, thereby increasing the efficiency of methane cracking;

[0020] (3) Using molten metal high temperature cracking, the cracking rate of CH4 is as high as 99.9%;

[0021] (4) The carbon black produced by the high-temperature cracking reaction is cleaned by a carbon scraping device, and condensed, washed and collected by a carbon collecting and cleaning device to produce high-quality carbon black. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0023] Figure 1 This is a three-dimensional diagram of a methane cracking hydrogen production system in one embodiment of the utility model;

[0024] Figure 2 This is a structural diagram of a methane cracking hydrogen production system in one embodiment of the utility model;

[0025] Figure 3 This is a schematic structural diagram of a molten metal reactor in one embodiment of the utility model;

[0026] Figure 4 This is a structural schematic diagram of a carbon collection and cleaning device in one embodiment of the utility model;

[0027] Figure 5It is a schematic structural diagram of a scraper in one embodiment of the utility model. DETAILED DESCRIPTION

[0028] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0029] Example 1

[0030] This embodiment provides a methane cracking hydrogen production system, see Figure 1-5 , including a molten metal reactor, wherein the molten metal reactor 3 is connected to a methane inlet pipe 5 at the bottom, and is connected to a hydrogen exhaust pipe 6 and a carbon guide pipe 2 at the top. The molten metal reactor 3 includes a shell 7, and the interior of the shell 7 is sequentially arranged from bottom to top as a buffer zone 8, a reaction zone 9 and a hydrogen buffer zone 10. The buffer zone 8 is used to diffuse the methane gas so that it enters the reaction zone 9 evenly and smoothly. The methane undergoes a high-temperature cracking reaction in the reaction zone 9 to generate hydrogen and carbon black. The hydrogen enters the hydrogen buffer zone 10 upward and enters the hydrogen purification system C through the hydrogen exhaust pipe I6. The carbon black is deposited upward at the bottom of the hydrogen buffer zone 10.

[0031] In this embodiment, a carbon collection and cleaning device for processing carbon black is also included. The carbon collection and cleaning device is connected to the methane cracking system via a carbon guide tube 2. A carbon scraping device 4 is provided in the methane cracking system. The carbon scraping device 4 is used to sweep the carbon black through the carbon guide tube 2 and enter the carbon collection and cleaning device.

[0032] The methane cracking system uses methane as raw material and performs high-temperature cracking reactions to generate hydrogen and carbon black. The carbon black is condensed, flushed and collected through a carbon collection and cleaning device to produce high-quality carbon black, and hydrogen and other gases can be separated. The hydrogen is subsequently purified and stored in a hydrogen storage device.

[0033] Example 2

[0034] Based on Example 1, this example further provides a preferred implementation of a methane cracking system. Figure 3, which includes a molten metal reactor, wherein the bottom of the molten metal reactor 3 is connected to a methane inlet pipe 5, and the upper part is connected to a hydrogen exhaust pipe 6 and a carbon guide pipe 2. The molten metal reactor 3 includes a shell 7, and the interior of the shell 7 is sequentially arranged from bottom to top as a buffer zone 8, a reaction zone 9 and a hydrogen buffer zone 10. The buffer zone 8 is used to diffuse the methane gas so that it enters the reaction zone 9 evenly and smoothly. The methane undergoes a high-temperature cracking reaction in the reaction zone 9 to generate hydrogen and carbon black. The hydrogen enters the hydrogen buffer zone 10 upward and enters the hydrogen purification system C through the hydrogen exhaust pipe I6. The carbon black is deposited upward at the bottom of the hydrogen buffer zone 10 and enters the carbon collection and cleaning device under the action of the carbon scraping device.

[0035] In this embodiment, the buffer zone 8 is composed of two buffer chambers, which are separated by a distributor 11, and the upper buffer chamber is separated from the reaction zone 9 by a gas distribution pipe 12. The reaction zone 9 is composed of a molten metal layer 901 of metal copper / tin, etc., a molten salt layer 902 of NaCl and a carbon deposition layer 903 from bottom to top, and a plurality of baffles 12 are arranged in the molten salt layer 902.

[0036] In this embodiment, the carbon deposit layer 903 is provided with a carbon discharge port with an opening inclined downward, and the carbon guide pipe 2 is connected to the carbon discharge port.

[0037] In this embodiment, the number of baffles 12 is set to four, which are symmetrically distributed on both sides of the axis of the shell 7, staggered and inclined in the vertical direction, and fixedly connected to the inner wall of the shell 7. The residence time of CH4 in the molten metal layer 901 is increased, thereby increasing the efficiency of methane cracking.

[0038] In this embodiment, the shell 7 includes an inner cylinder 701 (stainless steel + corundum), an outer cylinder 704 stainless steel 13 and a heat preservation and heat insulation layer 703 from the inside to the outside, and an electric heater 702 is installed outside the inner cylinder 701. The heat preservation and heat insulation layer 703 is provided outside the electric heater 70212 to prevent heat loss. The inner cylinder 701 stainless steel + corundum 1 is filled with metal (copper or tin), and the metal is heated to ≥1200°C under the action of the electric heater 70212 to form molten liquid metal.

[0039] In this embodiment, a water cooling jacket 13 is disposed outside the shell 7 of the hydrogen buffer zone 10 , and cooling water flows through the water cooling jacket 13 to cool down the hydrogen in the hydrogen buffer zone 10 .

[0040] In this embodiment, refer to Figure 3 , 5The carbon scraping device 4 includes a first motor 401 arranged on the top of the shell 7, and the rotating shaft 402 of the first motor 401 penetrates the carbon deposition layer 903, the molten salt layer 902 (NaCl) and the molten metal layer 901 (metal copper / tin, etc.) inward in sequence. A scraper 19 is arranged on the rotating shaft 402, and the scraper 19 is located on the surface of the carbon deposition layer 903. The first motor 401 controls the scraper 19 to rotate 180 degrees forward and backward. Carbon black floats on the molten salt layer 902 to form a carbon deposition layer 903. After accumulating to a certain height, it is swept to the carbon discharge port by the carbon scraping device 4A10. Furthermore, in order to prevent carbon black from being blocked in the carbon guide tube 2, a stirring device is also arranged in the middle of the carbon guide tube 2, including a second motor 403 fixed above the carbon guide tube 2, and the rotating shaft 19 of the second motor 403 penetrates into the carbon guide tube 2, and a stirring blade is arranged on the rotating shaft 19.

[0041] In this embodiment, four high temperature resistant thermocouples are installed on the rotating shaft 402, which are respectively located in the hydrogen buffer zone 10, the carbon deposition layer 903, the molten salt layer 902 (NaCl) and the molten metal layer 901 (metal copper / tin, etc.).

[0042] Example 3

[0043] Based on the above-mentioned embodiments 1 and 2, this embodiment specifically provides a preferred implementation of the carbon collection and cleaning device, see Figure 4 The carbon collection and cleaning device includes a carbon cleaning device 13 and a carbon collection device 14 arranged up and down. The carbon cleaning device 13 is connected to the molten metal reactor 3 through a carbon guide pipe 2. The bottom of the carbon cleaning device 13 is connected to the carbon collection device 14 through a pipeline. A butterfly valve 32 is arranged on the connected pipeline. The lower end of the carbon cleaning device 13 is a cone. A cooling water flushing port 15 is arranged on the side wall of the cone. The top of the carbon cleaning device 13 is provided with a cooling water flushing port 15 and a hydrogen discharge port. The number of the cooling water flushing ports 15 is two, and they are respectively connected to cooling water pipes. A valve is arranged on the cooling water pipe. The hydrogen discharge port is connected to a hydrogen discharge pipe II 16, and the hydrogen discharge pipe II 16 is connected to the hydrogen discharge pipe I 6. The carbon black enters the carbon cleaning device 13. , deposited inside the cone, a liftable sealing plate 17 is arranged above the inside of the cone, a third motor 18 for controlling the lifting of the sealing plate 17 is arranged on the top of the carbon cleaning device 13, and the third motor 18 is connected to the sealing plate 17 by a steel rope. After the carbon enters the carbon cleaning device 13, it is precipitated to a certain height, and the third motor 18 puts down the sealing plate 17, and opens the valve on the cone cooling water pipe, and adds cooling water into the cone of the carbon cleaning device 13, forming a water seal state for the carbon black above the sealing plate 17, and the carbon black is cleaned and cooled. After cleaning, the butterfly valve 32 above the carbon collecting device 14 is opened, and the carbon enters the carbon collecting device 14 downward, and the carbon black is stored in the carbon collecting device 14 and water-sealed to obtain high-quality carbon black.

[0044] As described above, the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A methane cracking hydrogen production system, characterized in that: The invention comprises a molten metal reactor, wherein a methane inlet pipe is connected to the bottom, a hydrogen exhaust pipe and a carbon guide pipe are connected to the top, and the molten metal reactor comprises a shell, wherein the interior of the shell is sequentially arranged as a buffer zone, a reaction zone and a hydrogen buffer zone from bottom to top, wherein the buffer zone is used to diffuse methane gas so that it enters the reaction zone, wherein methane undergoes a high-temperature cracking reaction in the reaction zone to generate hydrogen and carbon black, wherein the hydrogen enters the hydrogen buffer zone upward and is discharged through the hydrogen exhaust pipe I, and the carbon black is deposited upward at the bottom of the hydrogen buffer zone.

2. A methane cracking hydrogen production system according to claim 1, characterized in that: It also includes a carbon collection and cleaning device for processing carbon black. The carbon collection and cleaning device is connected to the methane cracking system through a carbon guide tube. The methane cracking system is provided with a carbon scraping device, which is used to push and sweep the carbon black into the carbon collection and cleaning device through the carbon guide tube.

3. A methane cracking hydrogen production system according to claim 1, characterized in that: The buffer zone is composed of two buffer chambers, which are separated by a distributor, and the upper buffer chamber is separated from the reaction zone by a gas distribution pipe. The reaction zone is composed of a molten metal layer, a molten salt layer and a carbon deposition layer from bottom to top, and a plurality of baffles are arranged in the molten salt layer.

4. A methane cracking hydrogen production system according to claim 1, characterized in that: The carbon deposit layer is provided with a carbon discharge port with an opening inclined downward, and the carbon guide pipe is connected to the carbon discharge port.

5. A methane cracking hydrogen production system according to claim 3, characterized in that: The number of the baffles is set to four, which are symmetrically distributed on both sides of the axis of the shell, arranged in a staggered and inclined manner in the vertical direction, and fixedly connected to the inner wall of the shell.

6. A methane cracking hydrogen production system according to claim 1, characterized in that: The shell includes an inner tube, an outer tube and a heat preservation and insulation layer from the inside to the outside. An electric heater is installed outside the inner tube, and a heat preservation and insulation layer is arranged outside the electric heater. The inner tube is filled with metal.

7. A methane cracking hydrogen production system according to claim 1, characterized in that: A water cooling jacket is arranged outside the shell of the hydrogen buffer zone, and cooling water is passed through the water cooling jacket to cool the hydrogen in the hydrogen buffer zone.

8. A methane cracking hydrogen production system according to claim 2, characterized in that: The carbon scraping device includes a first motor arranged on the top of the shell, the rotating shaft of the first motor inwardly penetrates the carbon deposition layer, the molten salt layer and the molten metal layer in sequence, a scraper is arranged on the rotating shaft, the scraper is located on the surface of the carbon deposition layer, the first motor controls the scraper to rotate 180 degrees forward and reversely, and the carbon black floats on the molten salt layer to form a carbon deposition layer. After accumulating to a certain height, it is swept to the carbon discharge port by the carbon scraping device. A stirring device is also arranged in the middle of the carbon guide tube, including a second motor fixed above the carbon guide tube, the rotating shaft of the second motor penetrates into the carbon guide tube, and a stirring blade is arranged on the rotating shaft.

9. A methane cracking hydrogen production system according to claim 8, characterized in that: Four high-temperature resistant thermocouples are installed on the rotating shaft and are respectively located in the hydrogen buffer zone, the carbon deposition layer, the molten salt layer and the molten metal layer.

10. A methane cracking hydrogen production system according to claim 2, characterized in that: The carbon collection and cleaning device comprises a carbon cleaning device and a carbon collection device arranged up and down, the carbon cleaning device is connected to the molten metal reactor through a carbon guide pipe, the bottom of the carbon cleaning device is connected to the carbon collection device by a pipeline, a butterfly valve is arranged on the connected pipeline, the lower end of the carbon cleaning device is a cone, a cooling water flushing port is arranged on the side wall of the cone, a cooling water flushing port and a hydrogen discharge port are arranged on the top of the carbon cleaning device, the number of the cooling water flushing ports is two, respectively connected to a cooling water pipe, a valve is arranged on the cooling water pipe, the hydrogen discharge port is connected to a hydrogen discharge pipe II, and the hydrogen discharge pipe II is connected to the hydrogen discharge pipe I, the carbon black enters the carbon cleaning device and is deposited inside the cone, a liftable sealing plate is arranged above the inside of the cone, a third motor for controlling the lifting of the sealing plate is arranged on the top of the carbon cleaning device, and the third motor and the sealing plate are connected by a steel rope.

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