Coal pyrolysis hydrogen production coupling magnesium-based hydrogen storage system and process method

Abstract

The invention discloses a coal pyrolysis hydrogen production coupling magnesium-based hydrogen storage system and a process method. The first input end of the pyrolyzing furnace is connected to the output end of raw coal, the first output end of the pyrolyzing furnace is connected to the input end of the clean coal storage device, and the second output end of the pyrolyzing furnace is connected to the input end of the purification device; the first output end of the hydrogenation device is connected to the first input end of the reforming extraction device; the second output end of the hydrogenation device is connected to the second input end of the diesel hydrogenation device; the output ends of the calcined dolomite, ferrosilicon powder and fluorite powder pellets are connected to the second input end of the reduction furnace, the output end of the reduction furnace is connected to the input end of the modification device, and the output end of the modification device is connected to the second input end of the magnesium-based hydrogen storage device; the output end of the diesel hydrogenation device is connected to the second input end of the reforming extraction device. Through high coupling of coal pyrolysis hydrogen production and magnesium-based hydrogen storage, an integrated industrial chain of coal hydrogen production, hydrogen storage and transportation and the like is formed, and finally efficient and low-carbon operation of the hydrogen production, storage and transportation process is achieved.

Description

Technical Field

[0001] The present application relates to the field of hydrogen energy technology, and in particular to a coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system and a process method. Background Art

[0002] Coal-to-hydrogen, as a key technology for converting coal resources into hydrogen, has become increasingly important as a hydrogen source with the vigorous development of the hydrogen energy industry in recent years. Modern coal-to-hydrogen technologies mainly include hydrogen produced as a byproduct of coal pyrolysis and hydrogen produced through the water-gas shift reaction after coal gasification. Both methods can achieve large-scale production of hydrogen. With the continuous maturity and widespread application of carbon capture, storage and utilization (CCUS) technology, the coal-to-hydrogen industry is gradually transforming towards low-carbonization and energy diversification.

[0003] However, the storage and transportation of hydrogen energy is still one of the bottlenecks restricting the development of the hydrogen energy industry chain. Although the technology of gaseous hydrogen storage is mature, it has problems such as high pressure, strict technical requirements for equipment and limited transportation capacity. Organic liquid hydrogen storage faces challenges due to the complex dehydrogenation process and high energy consumption. Summary of the invention

[0004] The embodiment of the present application provides a coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system and process method, which greatly improves the energy utilization efficiency of hydrogen production and storage, reduces the cost of hydrogen storage and transportation, solves the technical problems of hydrogen production, storage and transportation, and greatly reduces the overall cost of hydrogen.

[0005] In a first aspect, an embodiment of the present application provides a coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system, comprising a pyrolysis furnace, a purification device, a clean coal storage device, a PSA hydrogen production device, a hydrogenation device, a reduction furnace, a modification device, a magnesium-based hydrogen storage device, a reforming extraction device, and a diesel hydrogenation device; the first input end of the pyrolysis furnace is connected to the output end of the raw coal, the first output end of the pyrolysis furnace is connected to the input end of the clean coal storage device, and the second output end thereof is connected to the input end of the purification device; the first output end of the purification device is connected to the input end of the PSA hydrogen production device, and the second output end of the purification device is connected to the first input end of the hydrogenation device; the first output end of the hydrogenation device is connected to the first input end of the reforming extraction device; the first output end of the PSA hydrogen production device is respectively connected to the magnesium-based hydrogen storage device The first input end of the PSA hydrogen production device is connected to the first input end of the reduction furnace, and the second output end of the hydrogenation device is connected to the second input end of the diesel hydrogenation device; the output end of the calcined white, ferrosilicon powder and fluorite powder pellets is connected to the second input end of the reduction furnace, the output end of the reduction furnace is connected to the input end of the modification device, and the output end of the modification device is connected to the second input end of the magnesium-based hydrogen storage device, and the magnesium-based hydrogen storage device is used for storing or transporting hydrogen; the first output end of the diesel hydrogenation device is connected to the second input end of the reforming extraction device, and the second output end of the diesel hydrogenation device is connected to the high-quality diesel product line; the output end of the reforming extraction device is connected to the benzene and aromatics product line.

[0006] In combination with the first aspect, in a possible implementation, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system also includes a PSA oxygen production device; the input end of the PSA oxygen production device is connected to the outside air, and the first output end thereof is connected to the second input end of the pyrolysis furnace.

[0007] In combination with the first aspect, in a possible implementation, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system also includes a PSA nitrogen production device; the input end of the PSA nitrogen production device is connected to the second output end of the PSA oxygen production device, and the output end of the PSA nitrogen production device is connected to the nitrogen product line.

[0008] In combination with the first aspect, in a possible implementation manner, the first output end of the PSA hydrogen production device is connected to the second input end of the pyrolysis furnace.

[0009] In a second aspect, an embodiment of the present application provides a method for producing hydrogen from coal pyrolysis coupled with magnesium-based hydrogen storage, including the system for producing hydrogen from coal pyrolysis coupled with magnesium-based hydrogen storage as described in the first aspect or any possible implementation of the first aspect, and further comprising:

[0010] S1: transporting raw coal to a pyrolysis furnace and treating it with an oxygen-enriched pyrolysis process to obtain clean coal and raw coal gas;

[0011] S2: transporting the raw coal gas obtained in step S1 to a purification device, removing pollutants therein through the purification device, and separating coal gas and coal tar;

[0012] S3: transporting the coal gas obtained in step S2 to a PSA hydrogen production device for gas separation to obtain desorbed gas and high-purity hydrogen;

[0013] S4: transporting the coal gas in step S2 and part of the high-purity hydrogen obtained in step S3 to a hydrogenation unit for hydrogenation treatment to obtain diesel components and naphtha;

[0014] S5: transporting the diesel component obtained in step S4 and part of the high-purity hydrogen remaining in step S3 to a diesel hydrogenation unit to perform deep hydrogenation treatment on the diesel component to obtain high-quality diesel and naphtha;

[0015] S6: transporting all the naphtha obtained in steps S4 and S5 to a reforming and extraction unit for reforming and extraction treatment to finally obtain benzene and aromatic products;

[0016] S7: The desorbed gas obtained in step S3 is used as a reduction furnace fuel, and is transported to the reduction furnace together with calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets to be reduced to generate crude magnesium, and the crude magnesium is refined to produce magnesium ingots;

[0017] S8: transporting the magnesium ingot obtained in step S7 to a modification device for modification to obtain a magnesium-based hydrogen storage material;

[0018] S9: transporting the remaining high-purity hydrogen in step S3 and the magnesium-based hydrogen storage material obtained in step S8 to a magnesium-based hydrogen storage device for hydrogen storage operation.

[0019] In conjunction with the second aspect, in a possible implementation, outside air is transported to a PSA oxygen generator, and oxygen-rich gas and nitrogen-rich gas are obtained through the efficient separation technology of the PSA oxygen generator;

[0020] The obtained oxygen-rich gas is transported to the pyrolysis furnace as a combustion-supporting gas.

[0021] In combination with the second aspect, in a possible implementation, the nitrogen-rich gas is transported to a PSA nitrogen production device for deep purification to obtain high-purity nitrogen.

[0022] In combination with the second aspect, in a possible implementation, part of the desorbed gas in S3 is transported to the pyrolysis furnace as fuel.

[0023] In conjunction with the second aspect, in a possible implementation, a method for preparing pellets of calcined silicon, ferrosilicon powder and fluorite powder is as follows:

[0024] Heat the dolomite in a rotary kiln or a vertical kiln to 1100-1300°C and burn it into calcined white;

[0025] Calcined ferrosilicon powder, ferrosilicon powder and fluorite powder are measured and mixed according to proportion, ground and pressed into pellets.

[0026] In combination with the second aspect, in a possible implementation, the desorbed gas obtained in step S3 is used as a reduction furnace fuel, and is transported to a reduction furnace together with calcined white, ferrosilicon powder and fluorite powder pellets to be reduced to generate crude magnesium, and the crude magnesium is refined to produce magnesium ingots, including:

[0027] S701: transporting the desorbed gas obtained in step S3 together with calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets into a reduction furnace;

[0028] S702: In the reduction furnace, the desorbed gas is used as the main fuel source, and the high temperature generated by combustion provides the required heat energy for the reduction reaction;

[0029] S703: The reducing substances in the calcined white and ferrosilicon powder undergo a reduction reaction at high temperature to generate metal magnesium vapor, and the fluorite powder acts as a catalyst to promote the reaction;

[0030] S704: Magnesium vapor is condensed and collected to obtain crude magnesium, which is then refined to obtain magnesium ingots.

[0031] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects:

[0032] The coal pyrolysis hydrogen production coupled magnesium-based hydrogen storage system provided in the embodiment of the present application includes a pyrolysis furnace, a purification device, a clean coal storage device, a PSA hydrogen production device, a hydrogenation device, a reduction furnace, a modification device, a magnesium-based hydrogen storage device, a reforming extraction device and a diesel hydrogenation device. The working principle is as follows: First, the raw coal is sent to the pyrolysis furnace and treated with oxygen-enriched pyrolysis technology. This process separates the volatile pollutants in the coal by pyrolysis. At the same time, the process technology has high pyrolysis efficiency, high gas content of effective components of the coal gas produced, and also generates clean coal products, realizing the qualitative and clean utilization of coal resources. Subsequently, the coal gas is passed through the purification device, and the pollutants therein are removed through a fine purification process to obtain purified coal gas and coal tar. This step ensures the purity of the subsequent processing raw materials. The coal gas is sent to the PSA hydrogen production device for gas separation to obtain desorbed gas and high-purity hydrogen. Part of the high-purity hydrogen is directly used in the hydrogenation unit to produce diesel components and naphtha. The remaining high-purity hydrogen and the diesel components obtained are further deeply hydrogenated in the hydrocracking unit to produce more naphtha and high-quality diesel. This series of operations not only improves the utilization rate of hydrogen, but also maximizes the value conversion of coal gas. The obtained naphtha is sent to the reforming and extraction unit, and after reforming and extraction, benzene and aromatic products are finally obtained. This step converts low-value naphtha into high-value-added chemical products, realizes the diversification and high-value utilization of coal tar deep processing products, and improves the economic benefits of the overall process. The desorbed gas released by coal gas hydrogen extraction is used as fuel for the reduction furnace. The processed and prepared calcined white, ferrosilicon powder and fluorite powder pellets are sent to the reduction furnace for reduction reaction to generate crude magnesium, which is refined to produce magnesium ingots. Subsequently, the magnesium ingot is modified and converted into a magnesium-based hydrogen storage material. This step improves the molecular structure of magnesium, making it easier to combine with hydrogen. Finally, the magnesium-based hydrogen storage material and the remaining high-purity hydrogen are sent to the magnesium-based hydrogen storage device for hydrogen storage operation, and the high hydrogen storage density and rapid hydrogen absorption and release performance of the magnesium-based hydrogen storage material are utilized to achieve safe and efficient storage of hydrogen. Therefore, this application highly couples coal pyrolysis hydrogen production with magnesium-based hydrogen storage to form an integrated industrial chain of coal-to-hydrogen production, hydrogen storage and transportation, and ultimately achieves efficient and low-carbon operation of the hydrogen "production, storage and transportation" process, reducing the unit comprehensive cost of hydrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 A schematic structural diagram of an implementation of a coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system provided in an embodiment of the present application;

[0035] Figure 2 A flow chart of a coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage process provided in an embodiment of the present application;

[0036] Figure 3 A schematic structural diagram of another embodiment of the coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system provided in an example of the present application.

[0037] Icons: 1-pyrolysis furnace; 2-purification device; 3-clean coal storage device; 4-PSA hydrogen production device; 5-hydrogenation device; 6-reduction furnace; 7-modification device; 8-magnesium-based hydrogen storage device; 9-reforming extraction device; 10-raw coal; 11-calcined charcoal, ferrosilicon powder and fluorite powder pellets; 12-benzene and aromatics product line; 13-PSA oxygen production device; 14-PSA nitrogen production device; 15-outside air; 16-nitrogen product line; 17-diesel hydrogenation device; 18-coal tar storage device. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0039] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present application and simplifying the description, 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 application. The terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0040] The present application embodiment provides a coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system, such as Figure 1As shown, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system includes a pyrolysis furnace 1, a purification device 2, a clean coal storage device 3, a PSA (Pressure Swing Adsorption) hydrogen production device 4, a hydrogenation device 5, a reduction furnace 6, a modification device 7, a magnesium-based hydrogen storage device 8, a reforming extraction device 9 and a diesel hydrogenation device 17. The first input end of the pyrolysis furnace 1 is connected to the output end of the raw coal 10. The first output end of the pyrolysis furnace 1 is connected to the input end of the clean coal storage device 3, and the second output end thereof is connected to the input end of the purification device 2. The clean coal in the clean coal storage device 3 can be used to produce carbon materials such as electrode materials and activated carbon.

[0041] Specifically, the raw coal 10 is transported to the pyrolysis furnace 1 and treated by an oxygen-enriched pyrolysis process to obtain clean coal and raw coal gas. The raw coal gas is transported to the purification device 2, where pollutants are removed and coal gas and coal tar are separated.

[0042] Table 1 - Composition of coal gas

[0043] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> <![CDATA[N2]]> <![CDATA[O2]]> <![CDATA[C m H n ]]> <![CDATA[H2S]]> Proportion% 24.3 12.32 7.58 7.81 45.5 0.50 1.50 0.08

[0044] Table 2 - Composition of coal gas

[0045] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> <![CDATA[N2]]> <![CDATA[O2]]> <![CDATA[C m H n ]]> <![CDATA[H2S]]> Proportion% 41.42 15.1 5.26 29.67 6.66 0.42 0.49 0.04

[0046] Compared with the traditional internal combustion and internal heating distillation process, the nitrogen content in the treated coal gas usually accounts for about 45%, and the content of effective gases CO, CH4, and H2 is less than 50%. The detailed components are shown in Table 1. However, it can be clearly seen from Table 2 that after treatment with oxygen-enriched pyrolysis technology, the nitrogen content in the coal gas has been significantly reduced, and the content of effective gases CO, CH4, and H2 is as high as 85%. Nitrogen, as an inert gas, not only reduces the calorific value of coal gas, but also increases energy consumption in the process of hydrogen production by pressure swing adsorption of coal gas. Therefore, this application effectively reduces the nitrogen content through oxygen-enriched pyrolysis technology, and correspondingly increases the effective gas content. We can make more full use of other gas components in the coal gas, thereby improving the overall energy utilization efficiency.

[0047] The first output end of the purification device 2 is connected to the input end of the PSA hydrogen production device 4, and the second output end of the purification device 2 is connected to the first input end of the hydrogenation device 5. The first output end of the hydrogenation device 5 is connected to the first input end of the reforming extraction device 9. The first output end of the PSA hydrogen production device 4 is respectively connected to the first input end of the magnesium-based hydrogen storage device 8, the second input end of the hydrogenation device 5 and the first input end of the diesel hydrogenation device 17, the second output end of the PSA hydrogen production device 4 is connected to the first input end of the reduction furnace 6, and the second output end of the hydrogenation device 5 is connected to the second input end of the diesel hydrogenation device 17. The output end of the calcined white, ferrosilicon powder and fluorite powder pellets 11 is connected to the second input end of the reduction furnace 6, the output end of the reduction furnace 6 is connected to the input end of the modification device 7, and the output end of the modification device 7 is connected to the second input end of the magnesium-based hydrogen storage device 8, which is used for hydrogen storage or transportation. The first output end of the diesel hydrogenation device 17 is connected to the second input end of the reforming extraction device 9, and the second output end of the diesel hydrogenation device 17 is connected to the high-quality diesel product line. The output end of the reforming extraction device 9 is connected to the benzene and aromatics product line 12 .

[0048] It should be noted that the working principle of the coal pyrolysis hydrogen production coupled with the magnesium-based hydrogen storage system is as follows: First, the raw coal 10 is fed into the pyrolysis furnace 1 and treated with oxygen-enriched pyrolysis technology. This process separates the volatile pollutants in the coal by pyrolysis. At the same time, the process technology has high pyrolysis efficiency, high content of effective components in the raw coal gas produced, and also generates clean coal products, realizing the qualitative and clean utilization of coal resources. Subsequently, the raw coal gas is passed through the purification device 2, and the pollutants therein are removed through a fine purification process to obtain purified coal gas and coal tar. This step ensures the purity of the subsequent processing raw materials. The coal gas is sent to the PSA hydrogen production device 4 for gas separation to obtain desorbed gas and high-purity hydrogen. Part of the high-purity hydrogen is directly used in the hydrogenation device 5 to produce diesel components and naphtha. The remaining part of the high-purity hydrogen is further deeply hydrogenated with the obtained diesel components in the hydrocracking unit to produce more naphtha and high-quality diesel. This series of operations not only improves the utilization rate of hydrogen, but also realizes the maximum value conversion of coal gas. The obtained naphtha is sent to the reforming and extraction device 9, and after reforming and extraction treatment, benzene and aromatic products are finally obtained. This step converts low-value naphtha into high-value-added chemical products, realizes the diversification and high-value utilization of coal tar deep-processing products, and improves the economic benefits of the overall process. The desorbed gas released by coal gas hydrogen extraction is used as fuel for the reduction furnace 6, and the processed and prepared calcined white, ferrosilicon powder and fluorite powder pellets 11 are sent to the reduction furnace 6 for reduction reaction to generate crude magnesium, and the crude magnesium is refined to produce magnesium ingots. Subsequently, the magnesium ingot is modified and converted into a magnesium-based hydrogen storage material. This step improves the molecular structure of magnesium, making it easier to combine with hydrogen. Finally, the magnesium-based hydrogen storage material and the remaining high-purity hydrogen are sent to the magnesium-based hydrogen storage device 8 for hydrogen storage operation, and the high hydrogen storage density and rapid hydrogen absorption and desorption performance of the magnesium-based hydrogen storage material are utilized to achieve safe and efficient storage of hydrogen. Therefore, this application highly couples coal pyrolysis hydrogen production with magnesium-based hydrogen storage to construct an integrated industrial chain of coal-to-hydrogen production, hydrogen storage and transportation, and ultimately achieves efficient and low-carbon operation of the hydrogen "production, storage and transportation" process, thereby reducing the unit comprehensive cost of hydrogen.

[0049] In the embodiment of the present application, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system further includes a PSA (Pressure Swing Adsorption) oxygen production device. The input end of the PSA oxygen production device 13 is connected to the outside air 15, and its first output end is connected to the second input end of the pyrolysis furnace 1.

[0050] In the embodiment of the present application, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system further includes a PSA nitrogen production device 14. The input end of the PSA (Pressure Swing Adsorption) nitrogen production device is connected to the second output end of the PSA oxygen production device 13, and the output end of the PSA nitrogen production device 14 is connected to the nitrogen product line 16.

[0051] The present application adopts pressure swing adsorption oxygen production technology to produce oxygen-enriched gas with an oxygen content of not less than 55% as a combustion aid. The nitrogen-enriched gas after oxygen production is used as a raw material for air-press nitrogen production to produce high-purity nitrogen for use as industrial nitrogen for the device, which can greatly reduce the operating cost and energy consumption of air-press nitrogen production and improve the purity of nitrogen products.

[0052] In the embodiment of the present application, the first output end of the PSA hydrogen production device 4 is connected to the second input end of the pyrolysis furnace 1 .

[0053] In the embodiment of the present application, the embodiment of the present application provides a coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage process, such as Figure 2 As shown, the process method utilizes the above-mentioned coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system, comprising:

[0054] S1: The raw coal 10 is transported to the pyrolysis furnace 1 and treated by an oxygen-enriched pyrolysis process to obtain clean coal and raw coal gas.

[0055] S2: The raw coal gas obtained in step S1 is transported to the purification device 2, where pollutants are removed and coal gas and coal tar are separated.

[0056] S3: The coal gas obtained in step S2 is transported to the PSA hydrogen production device 4 for gas separation to obtain desorbed gas and high-purity hydrogen.

[0057] S4: The coal gas in step S2 and part of the high-purity hydrogen obtained in step S3 are transported to the hydrogenation device 5 for hydrogenation treatment to obtain diesel components and naphtha.

[0058] S5: The diesel component obtained in step S4 and part of the high-purity hydrogen remaining in step S3 are transported to the diesel hydrogenation device 17 to perform deep hydrogenation treatment on the diesel component to obtain high-quality diesel and naphtha.

[0059] It should be noted that deep hydroprocessing technology can further reduce the sulfur and nitrogen content in diesel components, reduce the aromatic content, and increase the cetane number, thereby producing high-quality diesel. In the process of hydroprocessing of diesel components, in addition to producing high-quality diesel, more naphtha may also be produced.

[0060] S6: All the naphtha obtained in steps S4 and S5 are transported to the reforming and extraction device 9 for reforming and extraction treatment to finally obtain benzene and aromatic products. The reforming and extraction process provides stable and sufficient raw materials for the production of benzene and aromatic products, which helps to meet the market demand for these chemicals and promote the development of related industrial chains.

[0061] S7: The desorbed gas obtained in step S3 is used as a fuel for the reduction furnace 6, and is transported to the reduction furnace 6 together with the calcined white, ferrosilicon powder and fluorite powder pellets 11, and is reduced to generate crude magnesium, which is refined to produce magnesium ingots. Specifically, the magnesium content reaches 99.99%. Table 3 shows the composition of the desorbed gas.

[0062] Table 3 - Composition of desorbed gas

[0063] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> <![CDATA[N2]]> <![CDATA[O2]]> <![CDATA[C m H n ]]> <![CDATA[H2S]]> Calorific value Proportion% 5.66 32.08 13.21 33.96 9.43 0.94 4.62 0.10 4752kcal

[0064] This process uses the desorbed gas after hydrogen extraction from coal gas as pyrolysis fuel, replacing the direct combustion of coal gas, effectively avoiding the waste of hydrogen during the coal gas combustion process, thereby improving the overall utilization rate of hydrogen.

[0065] S8: The magnesium ingot obtained in step S7 is transported to the modification device 7 for modification treatment to obtain a magnesium-based hydrogen storage material.

[0066] Specifically, the magnesium ingot obtained in step S7 is transported to the modification device 7 for modification treatment to obtain a magnesium-based hydrogen storage material, improve the performance of the magnesium-based hydrogen storage material, increase its hydrogen storage capacity, reduce the hydrogen absorption and desorption temperature, accelerate the hydrogen absorption and desorption rate, and enhance the stability and corrosion resistance of the material.

[0067] S9: The remaining high-purity hydrogen gas in step S3 and the magnesium-based hydrogen storage material obtained in step S8 are transported to the magnesium-based hydrogen storage device 8 for hydrogen storage operation.

[0068] It should be noted that magnesium-based hydrogen storage materials can undergo obvious hydrogen absorption reactions within a temperature range below 100°C, which means that at relatively low temperatures, magnesium-based hydrogen storage materials can effectively absorb and store hydrogen. When the temperature rises to around 280°C, magnesium-based hydrogen storage materials can release hydrogen, that is, the dehydrogenation process. This process is the reverse reaction of hydrogen absorption, so that the stored hydrogen can be effectively released for use when needed. This controllability enables magnesium-based hydrogen storage materials to flexibly respond to different energy needs in hydrogen energy systems and realize on-demand supply of hydrogen. Therefore, the hydrogen absorption and dehydrogenation capabilities of magnesium-based hydrogen storage materials within a specific temperature range not only improve the storage and release efficiency of hydrogen, but also promote the development and application of hydrogen energy technology.

[0069] The entire process of this application builds a closed-loop coal-based hydrogen storage and transportation system through the high coupling of coal fractionation, magnesium smelting and hydrogen energy. This system can significantly reduce the manufacturing cost and storage and transportation cost of hydrogen, providing an economically feasible solution for the widespread application of hydrogen energy. At the same time, the successful application of this technology also provides strong technical support for the promotion and development of the hydrogen energy industry.

[0070] Specifically, magnesium-based hydrogen storage materials can be widely used in new energy systems such as automobiles and trucks due to their unique properties, significantly improving the energy density of electric vehicles, thereby extending the driving range. In addition, magnesium-based hydrogen storage materials are also an important part of the fuel cell field. As a device that efficiently converts chemical energy into electrical energy, fuel cells rely on efficient hydrogen storage materials to store and supply hydrogen when using hydrogen as fuel. Magnesium-based hydrogen storage materials are the ideal choice for this demand, providing a reliable fuel guarantee for the stable operation of hydrogen fuel cells. Looking to the future, the application prospects of magnesium-based hydrogen storage materials will be broader. It will not only play an important role in the fields of hydrogen storage and transportation, but will also be widely used in hydrogen refueling stations, fuel vehicles, electric vehicles, aviation industry, chemical hydrogenation industry and other fields. Through the magnesium-based hydrogen storage goals achieved by this application, we are expected to promote the further development of the hydrogen economy and contribute to the construction of a clean, efficient and sustainable energy system.

[0071] In the embodiment of the present application, the outside air 15 is transported to the PSA oxygen generator 13, and the oxygen-rich gas and the nitrogen-rich gas are obtained through the efficient separation technology of the PSA oxygen generator 13.

[0072] The obtained oxygen-rich gas is transported to the pyrolysis furnace 1 as a combustion-supporting gas.

[0073] In the embodiment of the present application, the nitrogen-rich gas is transported to the PSA nitrogen production device 14 for deep purification to obtain high-purity nitrogen.

[0074] It should be noted that the purity of high-purity nitrogen reaches 99.9%. This high purity can be directly used in industrial equipment, and can also be used in many fields such as semiconductor manufacturing, electronic component packaging, food preservation, and pharmaceutical production, and has wide application value.

[0075] In the embodiment of the present application, part of the desorbed gas in S3 is transported to the pyrolysis furnace 1 as fuel.

[0076] It should be noted that the embodiments of the present application can maximize the utilization of resources and use the desorbed gas produced after hydrogen extraction in the process as fuel. Compared with the traditional internal combustion and internal heat distillation process using self-produced coal gas, it avoids the traditional coal distillation using self-produced coal gas as fuel, which not only reduces the production cost, but also improves the utilization rate of hydrogen resources.

[0077] In the embodiment of the present application, the preparation method of the pellets 11 of calcined silicon, ferrosilicon powder and fluorite powder is as follows:

[0078] Dolomite is heated to 1100-1300℃ in a rotary kiln or a vertical kiln to be calcined white. This process removes volatile substances such as crystal water and carbon dioxide in the dolomite, making the calcined white more active and stable. The calcined white after this treatment can participate more efficiently in subsequent reactions, improving the overall reaction efficiency.

[0079] Calcined ferrosilicon powder, ferrosilicon powder and fluorite powder are metered, ground and pressed into pellets in proportion. This process not only ensures the uniform mixing of the raw materials, but also increases the bulk density and reaction surface area of ​​the raw materials through pelletization.

[0080] In the embodiment of the present application, the desorbed gas obtained in step S3 is used as the fuel of the reduction furnace 6, and is transported to the reduction furnace 6 together with the calcined white, ferrosilicon powder and fluorite powder pellets 11, and is reduced to generate crude magnesium, and the crude magnesium is refined to produce magnesium ingots, including:

[0081] S701: The desorbed gas obtained in step S3 is transported to the reduction furnace 6 together with the calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets 11.

[0082] S702: In the reduction furnace 6, the desorbed gas is used as the main fuel source, and the high temperature generated by combustion provides the required heat energy for the reduction reaction. The desorbed gas is used as the main fuel source of the reduction furnace 6, which not only realizes the effective utilization of its energy, but also avoids the fuel waste or extra fuel consumption that may exist in the traditional process.

[0083] S703: The reducing substances in the calcined white and ferrosilicon powder undergo a reduction reaction at high temperature to generate metal magnesium vapor, and the fluorite powder acts as a catalyst to promote the reaction.

[0084] S704: Magnesium vapor is condensed and collected to obtain crude magnesium, which is then refined to obtain magnesium ingots with stable quality and excellent performance.

[0085] This embodiment proposes a coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system, which aims to efficiently utilize coal resources, produce high-purity hydrogen through the pyrolysis process, and use the byproduct desorption gas produced as fuel to prepare magnesium ingots, and finally obtain high-performance coal-based hydrogen storage materials through modification. This system not only realizes the clean and efficient use of coal, but also promotes the development of the hydrogen energy industry.

[0086] my country is currently vigorously promoting the development of the hydrogen energy industry. Yulin, Shaanxi can rely on existing industries to achieve rapid industrial transformation and high-quality development through coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage technology. Shaanxi Fugu and Shenmu magnesium metals have a production capacity of about 1,500 tons of semi-coke. If hydrogen is first extracted from these production processes and the extracted desorption gas is used as fuel for magnesium metal production, it is estimated that about 226,900 tons of hydrogen can be extracted annually. These low-cost hydrogens not only provide an important source of recombinant hydrogen for the development of the hydrogen energy industry in Yulin, Shaanxi, but also effectively avoid the energy waste caused by the direct combustion of hydrogen in the traditional coal gas treatment process.

[0087] Shaanxi Fugu has an annual production capacity of 500,000 tons of magnesium metal, accounting for nearly 60% of the national market share. However, unfortunately, most of the products are still sold in the form of crude magnesium, which leads to low added value and relatively limited profit margins. In order to enhance the value of the industry, we can consider utilizing these abundant hydrogen resources. According to the 10% hydrogen storage mass ratio, if 50% of the local hydrogen is stored using magnesium-based hydrogen storage technology, this will give rise to a huge demand for magnesium-based hydrogen storage materials.

[0088] Through the deep coupling between the above industries, not only has it injected strong impetus into the development of the hydrogen energy industry in Yulin, Shaanxi, but it has also provided a new path for the transformation and upgrading of the magnesium metal industry. Relying on the existing scale of the pyrolysis industry, through technological transformation and industrial upgrading, Yulin, Shaanxi has shown obvious advantages and huge potential in the development of the hydrogen energy industry, which is conducive to improving the overall competitiveness of the local economy and making important contributions to the realization of green and low-carbon development goals.

[0089] Another implementation mode of the present application is as follows: Figure 3 As shown, the coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system includes a pyrolysis furnace 1, a purification device 2, a clean coal storage device 3, a PSA (Pressure Swing Adsorption) hydrogen production device 4, a coal tar storage device 18, a reduction furnace 6, a modification device 7, and a magnesium-based hydrogen storage device 8. Specifically, the process method utilizes the above-mentioned coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system, and includes the following steps:

[0090] S101: transporting raw coal 10 to a pyrolysis furnace 1 and treating it with an oxygen-enriched pyrolysis process to obtain clean coal and raw coal gas, and selling the obtained clean coal;

[0091] S102: transporting the raw coal gas obtained in step S101 to the purification device 2, removing pollutants therein through the purification device 2, separating the coal gas and coal tar, and selling the separated coal tar;

[0092] S103: transporting the coal gas obtained in step S102 to the PSA hydrogen production device 4 for gas separation to obtain desorbed gas and high-purity hydrogen;

[0093] S104: the desorbed gas obtained in step S103 is used as a fuel for the reduction furnace 6, and is transported to the reduction furnace 6 together with the calcined white, ferrosilicon powder and fluorite powder pellets 11, and is reduced to generate crude magnesium, which is refined to produce magnesium ingots;

[0094] S105: transporting the magnesium ingot obtained in step S104 to a modification device 7 for modification to obtain a magnesium-based hydrogen storage material;

[0095] S106: The high-purity hydrogen obtained in step S103 and the magnesium-based hydrogen storage material obtained in step S105 are transported to the magnesium-based hydrogen storage device 8 for hydrogen storage operation.

[0096] Specifically, the clean coal is stored in the clean coal storage device 3 , and the separated coal tar is stored in the coal tar storage device 18 .

[0097] It should be noted that the clean coal can be sold after being processed, thus realizing the initial utilization of coal resources. Similarly, in this embodiment, the separated coal tar also has economic value and can be sold, further increasing the economic benefits of the entire process.

[0098] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0099] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system, characterized in that: It comprises a pyrolysis furnace (1), a purification device (2), a clean coal storage device (3), a PSA hydrogen production device (4), a hydrogenation device (5), a reduction furnace (6), a modification device (7), a magnesium-based hydrogen storage device (8), a reforming extraction device (9) and a diesel hydrogenation device (17); The first input end of the pyrolysis furnace (1) is connected to the output end of the raw coal (10), the first output end of the pyrolysis furnace (1) is connected to the input end of the clean coal storage device (3), and the second output end is connected to the input end of the purification device (2); The first output end of the purification device (2) is connected to the input end of the PSA hydrogen production device (4), and the second output end of the purification device (2) is connected to the first input end of the hydrogenation device (5); The first output end of the hydrogenation device (5) is connected to the first input end of the reforming extraction device (9); The first output end of the PSA hydrogen production device (4) is respectively connected to the first input end of the magnesium-based hydrogen storage device (8), the second input end of the hydrogenation device (5) and the first input end of the diesel hydrogenation device (17); the second output end of the PSA hydrogen production device (4) is connected to the first input end of the reduction furnace (6); and the second output end of the hydrogenation device (5) is connected to the second input end of the diesel hydrogenation device (17); The output end of the calcined silicon, ferrosilicon powder and fluorite powder pellets (11) is connected to the second input end of the reduction furnace (6), the output end of the reduction furnace (6) is connected to the input end of the modification device (7), the output end of the modification device (7) is connected to the second input end of the magnesium-based hydrogen storage device (8), and the magnesium-based hydrogen storage device (8) is used to store or transport hydrogen; The first output end of the diesel hydrogenation device (17) is connected to the second input end of the reforming extraction device (9), and the second output end of the diesel hydrogenation device (17) is connected to a high-quality diesel product line; The output end of the reforming extraction device (9) is connected to the benzene and aromatics product line (12).

2. The coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system according to claim 1, characterized in that: Also includes a PSA oxygen generator (13); The input end of the PSA oxygen production device (13) is connected to the outside air (15), and the first output end is connected to the second input end of the pyrolysis furnace (1).

3. The coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system according to claim 2, characterized in that: Also includes a PSA nitrogen generator (14); The input end of the PSA nitrogen generator (14) is connected to the second output end of the PSA oxygen generator (13), and the output end of the PSA nitrogen generator (14) is connected to the nitrogen product line (16).

4. The coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage system according to claim 1, characterized in that: The first output end of the PSA hydrogen production device (4) is connected to the second input end of the pyrolysis furnace (1).

5. A process for utilizing the coal pyrolysis hydrogen production coupled with a magnesium-based hydrogen storage system according to any one of claims 1 to 4, characterized in that: The steps include: S1: transporting raw coal (10) to a pyrolysis furnace (1) and treating it with an oxygen-enriched pyrolysis process to obtain clean coal and raw coal gas; S2: The raw coal gas obtained in step S1 is transported to a purification device (2), where pollutants are removed from the raw coal gas and coal tar is separated; S3: transporting the coal gas obtained in step S2 to a PSA hydrogen production device (4) for gas separation to obtain desorbed gas and high-purity hydrogen; S4: transporting the coal gas in step S2 and part of the high-purity hydrogen obtained in step S3 to a hydrogenation unit (5) for hydrogenation to obtain a diesel component and naphtha; S5: transporting the diesel component obtained in step S4 and part of the high-purity hydrogen remaining in step S3 to a diesel hydrogenation unit (17), performing deep hydrogenation treatment on the diesel component to obtain high-quality diesel and naphtha; S6: transporting all the naphtha obtained in steps S4 and S5 to a reforming and extraction unit (9) for reforming and extraction to finally obtain benzene and aromatic products; S7: The desorbed gas obtained in step S3 is used as a fuel for the reduction furnace (6), and is transported to the reduction furnace (6) together with calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets (11) to be reduced to generate crude magnesium, which is then refined to produce magnesium ingots; S8: transporting the magnesium ingot obtained in step S7 to a modification device (7) for modification to obtain a magnesium-based hydrogen storage material; S9: transporting the remaining high-purity hydrogen gas in step S3 and the magnesium-based hydrogen storage material obtained in step S8 to the magnesium-based hydrogen storage device (8) for hydrogen storage operation.

6. The method of coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage according to claim 5, characterized in that: The outside air (15) is transported to the PSA oxygen generator (13), and the oxygen-rich gas and the nitrogen-rich gas are obtained by the high-efficiency separation technology of the PSA oxygen generator (13); The obtained oxygen-rich gas is transported to the pyrolysis furnace (1) as a combustion-supporting gas.

7. The method of coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage according to claim 6, characterized in that: The nitrogen-rich gas is transported to the PSA nitrogen production device (14) for deep purification to obtain high-purity nitrogen.

8. The method of coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage according to claim 5, characterized in that: Part of the desorbed gas in S3 is transported to the pyrolysis furnace (1) as fuel.

9. The method of coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage according to claim 5, characterized in that: Preparation method of calcined white, ferrosilicon powder and fluorite powder pellets (11): Heat the dolomite in a rotary kiln or a vertical kiln to 1100-1300°C and burn it into calcined white; Calcined ferrosilicon powder, ferrosilicon powder and fluorite powder are measured and mixed according to proportion, ground and pressed into pellets.

10. The method of coal pyrolysis hydrogen production coupled with magnesium-based hydrogen storage according to claim 9, characterized in that: The desorbed gas obtained in step S3 is used as a fuel for the reduction furnace (6) and transported to the reduction furnace (6) together with calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets (11) to be reduced to generate crude magnesium, which is then refined to produce magnesium ingots, including: S701: transporting the desorbed gas obtained in step S3 together with calcined ferrosilicon powder, ferrosilicon powder and fluorite powder pellets (11) into a reduction furnace (6); S702: In the reduction furnace (6), the desorbed gas is used as the main fuel source, and the high temperature generated by combustion provides the required heat energy for the reduction reaction; S703: The reducing substances in the calcined white and ferrosilicon powder undergo a reduction reaction at high temperature to generate metal magnesium vapor, and the fluorite powder acts as a catalyst to promote the reaction; S704: Magnesium vapor is condensed and collected to obtain crude magnesium, which is then refined to obtain magnesium ingots.

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