Hydrogen production system with complementation of coal decoupling gasification and solar frequency division utilization

Abstract

The invention provides a hydrogen production system with complementation of coal decoupling gasification and solar frequency division utilization, comprising: a solar frequency division utilization unit suitable for decoupling sunlight into a long wave part and a short wave part according to wavelength so as to utilize the short wave part to generate power and generate electric energy; the water electrolysis unit is suitable for electrolyzing water under the action of electric energy to generate hydrogen and oxygen; the graded gasification unit is suitable for gasifying coal from the outside under the heat provided by the long-wave part to generate carbon monoxide; the water-gas conversion unit is suitable for performing water-gas conversion on the carbon monoxide from the grading gasification unit and water from the outside to generate hydrogen and carbon dioxide, and at least one part of the carbon dioxide is conveyed to the grading gasification unit to serve as a gasification agent; and the storage unit is suitable for storing the hydrogen generated by the water electrolysis unit and the water vapor conversion unit.

Description

Technical Field

[0001] At least one embodiment of the present disclosure relates to the field of hydrogen production, and in particular to a hydrogen production system that complements coal decoupled gasification and solar energy frequency division utilization. Background Art

[0002] Coal is an important energy source, accounting for more than half of the global energy consumption structure. In recent years, the coal energy conversion industry has been continuously improved, the scale has been continuously expanded, the technology has been continuously advanced, and the modern coal conversion production mode has been fully developed. However, the current coal energy conversion production scenario still has high energy consumption and serious carbon dioxide (CO2) emissions. The development of clean and efficient coal utilization technology is not only expected to solve the problem of high energy consumption, but also to make certain contributions to carbon peak and carbon neutrality. Coal gasification to produce hydrogen is an important way to cleanly utilize coal and plays an important role in the "hydrogen economy".

[0003] In order to further ease the pressure of emissions and achieve energy transformation, combining non-renewable fossil energy coal with renewable new energy solar energy is an important way and an important transitional means. In related technologies, the operating temperature of the gasifier is usually between 1250℃ and 1750℃. There are trough, Fresnel, dish and tower types of solar energy concentration. Among them, the concentration ratio of the trough type is below 100, and the concentration temperature is usually below 400℃. The concentration ratio of the Fresnel type is below 150, and the concentration temperature is usually below 450℃. The concentration ratio of the dish type and the tower type is between 300 and 3000, and the concentration temperature can reach above 750℃. In actual operation, the tower-type concentrated solar energy technology above 700℃ still has technical difficulties such as heliostat arrangement, heat storage, and recycling materials. If the concentration temperature reaches above 1000℃, the technical performance will be further reduced. Therefore, there is a mismatch between the gasification temperature (1250℃~1750℃) and the solar energy concentration temperature (below 1000℃). Summary of the invention

[0004] In view of this, the present disclosure provides a hydrogen production system that complements coal decoupled gasification and solar energy frequency division utilization, matches concentrated solar energy with coal pyrolysis, and realizes complementary, clean and efficient utilization of coal energy and renewable energy.

[0005] As one aspect of an embodiment of the present disclosure, a hydrogen production system that complements coal decoupled gasification and solar frequency division utilization is provided, including a solar frequency division utilization unit, a water electrolysis unit, a staged gasification unit, a water vapor conversion unit, and a storage unit. The solar frequency division utilization unit is suitable for decoupling sunlight into a long-wave portion and a short-wave portion according to wavelength, so as to generate electricity using the short-wave portion to generate electrical energy. The water electrolysis unit is suitable for electrolyzing water under the action of the above-mentioned electrical energy to produce hydrogen and oxygen. The staged gasification unit is suitable for gasifying coal from the outside under the heat provided by the above-mentioned long-wave portion to produce carbon monoxide. The water vapor conversion unit is suitable for performing water vapor conversion between carbon monoxide from the above-mentioned staged gasification unit and water from the outside to produce hydrogen and carbon dioxide, wherein at least a portion of the carbon dioxide is transported to the above-mentioned staged gasification unit as the above-mentioned gasifying agent. The storage unit is suitable for storing the hydrogen produced by the above-mentioned water electrolysis unit and the above-mentioned water vapor conversion unit.

[0006] According to an embodiment of the present disclosure, the above-mentioned staged gasification unit includes a pyrolysis reactor, a burner and a gasification reactor. The pyrolysis reactor is suitable for pyrolyzing the above-mentioned coal under the heat provided by the above-mentioned long-wave portion to produce coal char and pyrolysis gas. The burner is suitable for burning the pyrolysis gas from the above-mentioned pyrolysis reactor under the action of oxygen from the above-mentioned water electrolysis unit to produce flue gas. The gasification reactor causes the coal char from the above-mentioned pyrolysis reactor to undergo a gasification reaction with the above-mentioned gasification agent under the heat provided by the flue gas generated by the above-mentioned burner to produce carbon monoxide.

[0007] According to an embodiment of the present disclosure, the pyrolysis reactor includes a reaction tube, an insulation layer, a solar collector, a screw discharger and a solid-gas separator. The reaction tube is divided into a feed zone, a pyrolysis zone and a discharge zone from top to bottom. The insulation layer is at least sleeved on the periphery of the pyrolysis zone. The solar collector irradiates the long-wave portion to the pyrolysis zone through the insulation layer, so that the temperature of the coal entering the pyrolysis zone from the feed zone increases, a pyrolysis reaction occurs, and the coal char and the pyrolysis gas are produced. The screw discharger is arranged in the discharge zone, which is suitable for discharging the coal char and the pyrolysis gas from the reaction tube and controlling the residence time of the coal in the pyrolysis zone. The solid-gas separator is suitable for separating the coal char and the pyrolysis gas, and transporting the coal char to the gasification reactor, and transporting the pyrolysis gas to the burner.

[0008] According to an embodiment of the present disclosure, the pyrolysis reactor further includes a temperature detection device, which is suitable for obtaining the real-time temperature of the pyrolysis zone, wherein the screw feeder is configured to control the residence time of the coal according to the real-time temperature to ensure complete pyrolysis of the coal.

[0009] According to an embodiment of the present disclosure, the gasification reactor includes a furnace body, an outer furnace wall and a flue gas duct. A storage space is formed inside the furnace body, and the outer furnace wall is arranged outside the furnace body, and an outer flue is formed between the furnace body and the outer furnace wall. The flue gas duct is installed upright in the storage space, and the upper part of the flue gas duct is connected with the outer flue through a pipe. Among them, the burner is installed on the furnace body and is located below the flue gas duct, which is suitable for providing the flue gas from the bottom to the flue gas duct. The flue gas rises in the flue gas duct to heat the coal char flowing downward in the storage space and the carbon dioxide flowing upward, so that the coal char undergoes a gasification reaction, and the flue gas after cooling is discharged through the outer flue.

[0010] According to an embodiment of the present disclosure, the furnace body further comprises a feed pipe. The feed pipe passes through the outer furnace wall and is installed at the top of the furnace body to communicate with the accommodation space, wherein the coal enters the accommodation space via the feed pipe. The flue gas duct is located below the feed pipe, and the top of the flue gas duct is configured to be conical, so that the coal char falling on the top of the flue gas duct is evenly dispersed in the accommodation space.

[0011] According to an embodiment of the present disclosure, the gasification reactor further comprises a tubular member, which is horizontally extended and arranged below the flue gas duct and communicates with the flue gas duct, and the tubular member penetrates two opposite sides of the furnace body to guide the flue gas into the flue gas duct. There are two burners, which are symmetrically arranged at both ends of the axial direction of the tubular member to provide the flue gas by burning fuel.

[0012] According to an embodiment of the present disclosure, a discharge port is provided at the bottom of the furnace body, and the discharge port is suitable for allowing the ash generated by the coal char after the gasification reaction to be discharged. The furnace body also includes a gas distribution plate, which is obliquely installed between the periphery of the discharge port and the furnace body, so that an air chamber adjacent to the accommodation space is formed between the gas distribution plate and the bottom wall and side wall of the furnace body. Among them, the carbon dioxide from the water vapor conversion unit enters the air chamber from the air inlet located at the lower part of the air chamber, and enters the accommodation space through the multiple through holes on the gas distribution plate, contacts the coal char in the accommodation space, and allows the ash falling on the gas distribution plate to be discharged through the discharge port.

[0013] According to an embodiment of the present disclosure, baffles are arranged in the smoke duct and the outer smoke duct, so that the smoke flows along a serpentine path in the smoke duct and the outer smoke duct.

[0014] According to an embodiment of the present disclosure, the solar energy frequency division and utilization unit comprises a focusing assembly, a frequency divider and a photovoltaic panel. The focusing assembly is suitable for collecting the above-mentioned sunlight, and the frequency divider is suitable for decoupling the above-mentioned sunlight into the above-mentioned long-wave portion and the above-mentioned short-wave portion according to the wavelength. The photovoltaic panel is suitable for converting the above-mentioned short-wave portion into electrical energy.

[0015] According to the coal decoupled gasification and solar energy frequency division utilization complementary hydrogen production system of the embodiment of the present disclosure, the frequency division technology is utilized to separate the light of different wavelengths in the sunlight, and the short-wave portion of the sunlight is used for power generation; the long-wave portion of the sunlight is used to provide heat for the graded gasification unit, so that medium and high temperature concentrated solar energy and coal pyrolysis can match each other, converting low-grade light and heat into high-grade pyrolysis gas, thereby realizing the complementary, clean and efficient utilization of coal energy and renewable energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0017] Figure 1 A block diagram of a hydrogen production system combining coal decoupled gasification and complementary solar energy frequency division utilization according to an embodiment of the present disclosure is schematically shown;

[0018] Figure 2 Schematically shows a cross-sectional view of a pyrolysis reactor according to an embodiment of the present disclosure;

[0019] Figure 3 A schematic top view of a double-flue external heating gasification device according to an embodiment of the present disclosure is shown;

[0020] Figure 4 Schematically shows Figure 3 A cross-sectional view of the double-flue external heat gasification device taken along line AA shown; and

[0021] Figure 5 A partial cross-sectional view of a combustor according to an embodiment of the present disclosure is schematically shown.

[0022] The following are the descriptions of the reference numerals:

[0023] 1- Solar energy frequency division utilization unit;

[0024] 11- focusing assembly;

[0025] 12-divider;

[0026] 13- Photovoltaic panels;

[0027] 2- water electrolysis unit;

[0028] 3-stage gasification unit;

[0029] 31-pyrolysis reactor;

[0030] 311-reaction tube;

[0031] 3111-feeding area;

[0032] 3112-pyrolysis zone;

[0033] 3113-discharging area;

[0034] 312- thermal insulation layer;

[0035] 313-Solar Collector

[0036] 314-screw discharger;

[0037] 32-burner;

[0038] 321-Central channel;

[0039] 322-Gas fuel channel

[0040] 323-Solid fuel channel

[0041] 324-combustion channel;

[0042] 33-gasification reactor;

[0043] 331-furnace body;

[0044] 3311-feed pipe;

[0045] 3312-discharging port;

[0046] 3313-air inlet;

[0047] 3314-accommodation space;

[0048] 332-outer furnace wall;

[0049] 333-Flue gas duct;

[0050] 334- Tube parts;

[0051] 335-gas distribution board;

[0052] 336- baffle;

[0053] 337-external flue;

[0054] 338-Pipe fittings;

[0055] 339-smoke outlet;

[0056] 4- Water vapor conversion unit;

[0057] 5- Storage unit. DETAILED DESCRIPTION

[0058] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0059] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0060] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0061] When using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, and C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc. When using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, or C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.

[0062] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only reference directions of the drawings and are not intended to limit the scope of protection of the present disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or configurations will be omitted when they may cause confusion in the understanding of the present disclosure.

[0063] Figure 1 A block diagram of a hydrogen production system combining decoupled coal gasification and complementary solar energy frequency division utilization according to an embodiment of the present disclosure is schematically shown.

[0064] As one aspect of the embodiments of the present disclosure, a hydrogen production system combining coal decoupling gasification and complementary solar energy frequency division utilization is provided, such as Figure 1As shown, the hydrogen production system with coal decoupled gasification and complementary solar frequency division utilization includes a solar frequency division utilization unit 1, a water electrolysis unit 2, a graded gasification unit 3, a water vapor conversion unit 4 and a storage unit 5. The solar frequency division utilization unit 1 is suitable for decoupling sunlight into a long-wave part and a short-wave part according to the wavelength, so as to generate electricity by using the short-wave part, and to generate electric energy. The water electrolysis unit 2 is suitable for electrolyzing water under the action of electric energy to generate hydrogen and oxygen. The graded gasification unit 3 is suitable for gasifying coal from the outside under the heat provided by the long-wave part to generate carbon monoxide. The water vapor conversion unit 4 is suitable for performing water vapor conversion between carbon monoxide from the graded gasification unit 3 and water from the outside to generate hydrogen and carbon dioxide, wherein at least a portion of the carbon dioxide is transported to the graded gasification unit 3 as a gasifying agent. The storage unit 5 is suitable for storing the hydrogen generated by the water electrolysis unit 2 and the water vapor conversion unit 4.

[0065] According to the coal decoupled gasification and solar energy frequency division utilization complementary hydrogen production system of the embodiment of the present disclosure, the light of different wavelengths in the sunlight is separated by utilizing the frequency division technology, and the short-wave portion of the sunlight is used for power generation; the long-wave portion of the sunlight is used to provide heat for the graded gasification unit 3, so that the medium and high temperature concentrated solar energy and coal pyrolysis can match each other, converting low-grade light heat into high-grade pyrolysis gas, thereby realizing the complementary, clean and efficient utilization of coal energy and renewable energy.

[0066] According to an embodiment of the present disclosure, the storage unit 5 includes a storage tank and safety accessories. The safety accessories can be used to ensure the safety of hydrogen storage, for example, one or more of a pressure relief device, a temperature control device, a leak detection device, a fire and explosion prevention device, an emergency shut-off device, etc.

[0067] According to the embodiments of the present disclosure, Figure 1 As shown, the solar energy frequency division and utilization unit 1 comprises a focusing assembly 11, a frequency divider 12 and a photovoltaic panel 13. The focusing assembly 11 is suitable for collecting sunlight, and the frequency divider 12 is suitable for decoupling sunlight into a long-wave portion and a short-wave portion according to wavelength. The photovoltaic panel 13 is suitable for converting the short-wave portion into electrical energy.

[0068] According to the embodiments of the present disclosure, the solar energy frequency division and utilization unit 1 decouples sunlight into a short-wave portion (for example, a wavelength between 280nm and 870nm) of sunlight and a long-wave portion (for example, a wavelength of 870nm to +∞) of sunlight. The long-wave portion of sunlight is used to provide heat for coal pyrolysis, and the short-wave portion of sunlight is used to generate electrical energy through photoelectric conversion by photovoltaic panels, thereby realizing full-spectrum utilization of solar energy and improving the efficiency of solar energy utilization relative to single photovoltaic or photothermal utilization.

[0069] In an exemplary embodiment, the photovoltaic panel may be a gallium arsenide (GaInP / GaAs) photovoltaic cell.

[0070] According to the embodiments of the present disclosure, the pyrolysis temperature of coal is between 500°C and 900°C, and the focusing temperature of the long-wave portion of sunlight can reach 900°C, which can be used to drive the pyrolysis of coal and provide heat for the pyrolysis of coal.

[0071] According to the embodiments of the present disclosure, Figure 1 As shown, the staged gasification unit 3 includes a pyrolysis reactor 31, a burner 32 and a gasification reactor 33. The pyrolysis reactor 31 is suitable for pyrolyzing the coal in the pyrolysis reactor under the heat provided by the long-wave portion to produce coal char and pyrolysis gas. The burner 32 is suitable for burning the pyrolysis gas from the pyrolysis reactor 31 under the action of oxygen from the water electrolysis unit 2 to produce high-temperature flue gas. The gasification reactor 33 causes the coal char from the pyrolysis reactor 31 to undergo a gasification reaction with a gasifying agent under the heat provided by the flue gas generated by the burner 32 to produce carbon monoxide. The ultra-high temperature conventional gasification is decoupled into milder coal pyrolysis and coal char gasification, and the emission of harmful gases such as SOx and NOx can be reduced through coal gasification rather than direct combustion.

[0072] According to an embodiment of the present disclosure, coal gasification is decoupled by the staged gasification unit 3 into coal pyrolysis, coal char-CO2 gasification and partial syngas external combustion.

[0073] According to the embodiment of the present disclosure, the water in the water-gas conversion unit 4 for the water-gas conversion reaction with carbon monoxide may be condensed water, which is obtained by condensing water from the high-temperature flue gas of the burner 32 .

[0074] According to the embodiment of the present disclosure, the coal is first fed into the pyrolysis reactor 31, and the heat of the pyrolysis reactor 31 is provided by the long-wave portion of solar energy. In the case of air isolation, the coal undergoes a coal pyrolysis reaction in the pyrolysis reactor 31 to generate high-temperature semi-coke and pyrolysis gas. The high-temperature semi-coke enters the gasification reactor 33 and undergoes a gasification reaction with the CO2 gasification agent to generate carbon monoxide (CO), and CO undergoes a water vapor shift reaction with the condensed water in the high-temperature flue gas to generate hydrogen (H2) and CO2, and the CO2 returns to the gasification reactor 33 to participate in the reaction as a gasification agent, and the H2 is stored by the storage unit 5.

[0075] According to the embodiment of the present disclosure, pyrolysis gas, part of the synthesis gas (CO generated by the char-CO2 gasification reaction) and pure oxygen from the solar frequency division utilization unit 1 are subjected to oxygen-enriched combustion in the burner 32. The combustion produces high-temperature flue gas, which provides heat for the char-CO2 gasification, and then after heat recovery and condensation, moisture is removed and high-concentration CO2 gas is obtained, which is further sealed.

[0076] According to the embodiment of the present disclosure, the photovoltaic panel 13 uses the short-wave portion of sunlight to perform photoelectric conversion to generate electrical energy, and electrolyzes water in the water electrolysis unit 2 to produce pure oxygen and hydrogen. Pure oxygen and part of the synthesis gas (that is, CO) and pyrolysis gas from the gasification reactor are burned in oxygen-enriched combustion in the burner 32. After the flue gas produced by the combustion provides heat for the gasification reaction, it is condensed to remove moisture and obtain a high concentration of CO2, eliminating the energy consumption of CO2 separation after combustion, so that the coal decoupled gasification and solar energy frequency division utilization complementary hydrogen production system can achieve near-zero emissions as a whole. In addition, the use of the water electrolysis unit 2 to prepare pure oxygen can eliminate the air separation unit (ASU) and reduce the energy consumption of oxygen production.

[0077] According to an embodiment of the present disclosure, the electric energy generated by the photovoltaic panel 13 drives the water electrolysis unit 2 to electrolyze water into hydrogen and oxygen. Oxygen and part of CO and pyrolysis gas are burned in oxygen-enriched combustion, and part of the CO2 produced is used for the coal char-CO2 reaction, and the heat generated by the combustion is supplied to the coal char-CO2 reaction. The high-temperature flue gas produced by the combustion is condensed, the water therein is removed, and the remaining CO2 is further stored. The high-grade electric energy generated by the solar energy frequency division utilization unit 1 is further used to prepare high-grade hydrogen energy, and the by-product pure oxygen is used for oxygen-enriched combustion, eliminating the energy consumption of separating CO2 after combustion.

[0078] Figure 2 A cross-sectional view of a pyrolysis reactor according to an embodiment of the present disclosure is schematically shown.

[0079] like Figure 2 The perspective shown in the figure is that the dotted box on the left side of the figure is a partial enlarged view of the pyrolysis reactor on the right side of the figure, and the direction of the arrow indicates the direction of movement of the coal.

[0080] According to the embodiments of the present disclosure, Figure 2 As shown, the pyrolysis reactor 31 includes a reaction tube 311, a heat insulation layer 312, a solar collector 313, a screw discharger 314 and a solid-gas separator. The reaction tube 311 is divided into a feed zone 3111, a pyrolysis zone 3112 and a discharge zone 3113 from top to bottom. The heat insulation layer 312 is at least sleeved on the periphery of the pyrolysis zone 3112. The solar collector 313 irradiates the long-wave portion to the pyrolysis zone 3112 through the heat insulation layer 312, so that the temperature of the coal entering the pyrolysis zone 3112 from the feed zone 3111 increases, a pyrolysis reaction occurs, and coal char and pyrolysis gas are produced. The screw discharger 314 is arranged in the discharge zone 3113, which is suitable for discharging coal char and pyrolysis gas from the reaction tube 311 and controlling the residence time of the coal in the pyrolysis zone 3112. The solid-gas separator is suitable for separating the coal char and the pyrolysis gas, and transporting the coal char to the gasification reactor 33 , and transporting the pyrolysis gas to the burner 32 .

[0081] In such an embodiment, the pyrolysis temperature is 600°C-900°C, and the tar produced by coal pyrolysis is gaseous. The gaseous tar and pyrolysis gas are mixed together, and the tar and pyrolysis gas are separated from the coke gas-solid by a solid-liquid separator. Furthermore, the tar can be cooled to liquid state, and the tar can be separated from the pyrolysis gas.

[0082] According to the embodiment of the present disclosure, the coal enters the feed zone 3111 from the feed port at the top of the reaction tube 311 for preheating, and under the control of the spiral discharger 314 located in the discharge zone 3113, the coal further enters the pyrolysis zone 3112, and stays in the pyrolysis zone for a preset residence time (for example, 30 minutes or 50 minutes), so that the coal in the pyrolysis zone is pyrolyzed to produce coal coke and pyrolysis gas. Then, the coke and pyrolysis gas in the discharge zone 3113 are driven to be discharged from the discharge zone 3113 by the spiral discharger 314. At the same time, the coal in the feed zone 3111 enters the pyrolysis zone.

[0083] According to an embodiment of the present disclosure, the solar collector 313 may be an aperture, which focuses the long-wave portion of sunlight onto the coal in the pyrolysis zone 3112, raising the temperature of the coal to a level sufficient for pyrolysis.

[0084] According to an embodiment of the present disclosure, the pyrolysis reactor 31 further includes a temperature detection device (not shown in the figure), which is suitable for obtaining the real-time temperature of the pyrolysis zone 3112. The screw feeder is configured to control the residence time of the coal according to the real-time temperature to ensure complete pyrolysis of the coal.

[0085] According to an embodiment of the present disclosure, the temperature detection device is used to obtain the temperature data of the pyrolysis zone 3112 in real time. If the temperature of the pyrolysis zone is lower than the preset temperature value, the screw feeder reduces the rotation speed and prolongs the residence time of the coal in the pyrolysis zone to ensure that the coal is completely pyrolyzed. If the temperature is too high, the screw feeder increases the rotation speed and shortens the residence time. In this way, the screw feeder and the temperature detection device form a closed-loop control system, which can automatically adjust the residence time of the coal to adapt to the temperature fluctuations that may occur during the pyrolysis process and maintain the stability of the pyrolysis effect.

[0086] Figure 3 The top view of the double flue external heating gasification device according to the embodiment of the present disclosure is schematically shown. Figure 4 Schematically shows Figure 3 A cross-sectional view of AA of a double-flue external heating gasification device is shown.

[0087] According to the embodiments of the present disclosure, Figure 3 and Figure 4As shown, the gasification reactor 33 includes a furnace body 331, an outer furnace wall 332 and a flue gas duct 333. A storage space 3314 is formed inside the furnace body 331, and the outer furnace wall 332 is arranged outside the furnace body 331, and an outer flue 337 is formed between the furnace body 331 and the outer furnace wall 332. The flue gas duct 333 is vertically installed in the storage space 3314, and the upper part of the flue gas duct 333 is connected with the outer flue 337 through a pipe 338. Among them, the burner 32 is installed on the furnace body 331 and is located below the flue gas duct 333, which is suitable for providing flue gas from the bottom to the flue gas duct 333. The flue gas rises in the flue gas duct 333 to heat the coal char flowing downward in the storage space 3314 and the carbon dioxide (gasifying agent) flowing upward, so that the coal char undergoes a gasification reaction, and the flue gas after cooling is discharged through the outer flue duct 337.

[0088] According to the gasification reactor 33 of the embodiment of the present disclosure, a flue gas duct 333 is uprightly installed in the furnace body 331, and flue gas is provided from the lower part of the flue gas duct 333 through a flue gas supply assembly, so that the flue gas rises in the flue gas duct 333, and can indirectly and evenly heat the gasification raw materials flowing downward and the gasification agent flowing upward in the accommodating space 3314, so that the temperature of the accommodating space 3314 is kept at a high temperature during the process of the flue gas being discharged through the external flue 337, so that the gasification raw materials undergo a gasification reaction under the action of the gasification agent and the high temperature, which helps to fully carry out the gasification reaction and improves the gasification efficiency. By setting up the flue gas duct 333 and the external flue duct 337, the high-temperature flue gas can transfer heat from the flue gas duct 333 and the external flue duct 337 to the accommodating space 3314 in the opposite direction, thereby increasing the contact area between the accommodating space 3314 and the high-temperature flue gas, realizing a multi-faceted radiation heat transfer method, providing a more uniform heat distribution for the accommodating space 3314, improving the uniformity of heating, increasing the heat utilization efficiency of the high-temperature flue gas, and reducing heat loss.

[0089] According to an embodiment of the present disclosure, as shown in FIG. 4 , a pipe fitting 338 is connected between the upper portion of the flue gas duct 333 and the upper portion of the furnace body 331 , and a flue gas outlet 339 of the outer flue 337 is located at the lower portion of the outer furnace wall 332 , so that the residence time of the flue gas in the flue gas duct 333 and the outer flue 337 can be extended, thereby improving the heat exchange efficiency.

[0090] In an exemplary embodiment, as shown in FIG. 2 , the furnace body 331 includes but is not limited to being configured as a cylindrical or cubic cylindrical structure.

[0091] In an exemplary embodiment, the outer furnace wall 332 can be built with refractory bricks and heat-insulating castables, and the furnace body 331 can be built with refractory heat-conducting materials. An annular outer flue 337 is formed between the furnace body 331 and the outer furnace wall 332 .

[0092] In an illustrative embodiment, the outer furnace wall 332 is constructed of silicon carbide refractory bricks and thermal insulation castables, and the exterior is a steel shell.

[0093] In an exemplary embodiment, the pipe 338 may be a heat-resistant steel pipe lined with a refractory material.

[0094] According to an embodiment of the present disclosure, a gas outlet (not shown) is provided at the upper portion of the furnace body 331, which is suitable for allowing carbon monoxide (CO) gas generated by the gasification reaction between the gasification raw material (coal char) and the gasification agent (CO2) to be discharged.

[0095] According to an embodiment of the present disclosure, as shown in FIG. 4 , a discharge port 3312 is provided at the bottom of the furnace body 331 , and the discharge port 3312 is adapted to allow ash generated after the gasification reaction of the coal char to be discharged.

[0096] In an illustrative embodiment, coal char is in reverse contact with carbon dioxide under high temperature environment to produce a gasification reaction, and the generated target gas with CO as the main component is drawn out from the gas outlet at the upper part of the gasification channel, and the harmless ash produced by gasification is discharged through the discharge port 3312 at the bottom.

[0097] According to an embodiment of the present disclosure, as shown in the figure, the furnace body 331 further includes an air distribution plate 335, which is obliquely installed between the periphery of the discharge port 3312 and the furnace body 331, so that an air chamber adjacent to the accommodation space 3314 is formed between the air distribution plate 335 and the bottom wall and side wall of the furnace body 331. The carbon dioxide from the water vapor conversion unit enters the air chamber from the air inlet 3313 located at the lower part of the air chamber, and enters the accommodation space 3314 through the multiple through holes on the air distribution plate 335, contacts the coal char in the accommodation space 3314, and causes the ash falling on the air distribution plate 335 to be discharged through the discharge port 3312.

[0098] In such an embodiment, the pressure of the carbon dioxide gasifying agent can be stabilized through the gas chamber to ensure that the gasifying agent (i.e., CO2) can evenly pass through the through holes on the gas distribution plate 335, and further cool the ash around the discharge port 3312, thereby ensuring that the temperature of the discharge port 3312 is controlled within a reasonable material use temperature range.

[0099] In an exemplary embodiment, as shown in FIG4 , the gas distribution plate 335 may be a conical structure, made of heat-resistant steel. The bottom of the gas distribution plate 335 is a discharge port 3312, which is connected to the outside and is a discharge channel for the gasified ash.

[0100] In an illustrative embodiment, the gas distribution plate 335 is provided with evenly distributed through holes, and the gas distribution plate 335 is used to support ash and adjust the distribution of the gasifying agent so that the gasifying agent entering the containing space 3314 is evenly distributed.

[0101] In an exemplary embodiment, the angle between the gas distribution plate 335 and the horizontal plane can be between 15 and 70 degrees (for example, 15 degrees, 20 degrees, 30 degrees, 45 degrees, 60 degrees or 70 degrees) to promote the flow of residue to the discharge port 3312 and improve the distribution of the gasification agent in the containing space 3314.

[0102] In such an embodiment, the gasifying agent passing through the gas distribution plate 335 and the slag remaining after the gasification reaction with the coal char are reversely contacted for heat exchange, the temperature of the slag is reduced, and the temperature of the gasifying agent is preheated to the gasification reaction temperature.

[0103] According to an embodiment of the present disclosure, the gasification reactor further includes an air supply assembly (not shown in the figure). The air supply assembly is configured to blow loose air toward the discharge port 3312 to prevent ash and slag from accumulating at the discharge port 3312 .

[0104] In an illustrative embodiment, the gasification reactor further includes a valve (not shown in the figure), which cooperates with the loosening air component to allow or prevent the loosening air component from blowing loosening air toward the discharge port 3312 .

[0105] According to an embodiment of the present disclosure, as shown in FIG. 4 , baffles are arranged in the smoke duct 333 and the external smoke duct 337 , so that the smoke flows along a serpentine path in the smoke duct 333 and the external smoke duct 337 , thereby extending the residence time of the smoke in the smoke duct 333 and the external smoke duct 337 .

[0106] In an illustrative embodiment, the baffle may be made of heat-resistant steel.

[0107] According to the embodiments of the present disclosure, Figure 3 and Figure 4 As shown, the furnace body 331 further includes a feed pipe 3311, which passes through the outer furnace wall 332 and is installed on the top of the furnace body 331 to communicate with the accommodating space 3314, wherein the coal char enters the accommodating space 3314 via the feed pipe 3311. The flue gas pipe 333 is located below the feed pipe 3311, and the top of the flue gas pipe 333 is configured to be conical, so that the coal char falling on the top of the flue gas pipe 333 is evenly dispersed in the accommodating space 3314, which can prevent the raw materials from being concentrated, thereby ensuring that the gasification reaction in the entire accommodating space 3314 is more uniform, which helps to improve the gasification efficiency.

[0108] According to the embodiments of the present disclosure, Figure 3 and Figure 4As shown, the gasification reactor 33 further includes a tubular member 334. The tubular member 334 extends in the horizontal direction and is arranged below the flue gas duct 333, and is in communication with the flue gas duct 333. The tubular member 334 penetrates the two opposite sides of the furnace body 331 to guide the flue gas into the flue gas duct 333. There are two burners 32, which are symmetrically arranged at both ends of the axial direction of the tubular member 334 to provide flue gas by burning fuel (for example, pyrolysis oil gas from the pyrolysis reactor and oxygen from the water electrolysis unit 2).

[0109] In an alternative embodiment, the number of tubular members 334 can be multiple, and pairs of burners 32 are symmetrically arranged at both ends of the axial direction of the tubular member 334, suitable for providing flue gas by burning fuel (for example, pyrolysis oil gas from a pyrolysis reactor and oxygen from a hydrogen production component).

[0110] In an exemplary embodiment, the gasification reactor 33 further includes two tubular members 334, which are vertically arranged below the flue gas duct 333 and communicate with the flue gas duct 333. It is understandable that the flue gas supply assembly may also include one or more tubular members 334, and the specific number may be selected according to actual needs.

[0111] In an exemplary embodiment, a pair of burners 32 are disposed opposite to each other at both ends of each tubular member 334. Specifically, the combustion flame of each burner 32 is sprayed into the tubular member 334, so that the tubular member 334 has the function of a furnace, and the smoke generated by the combustion is also discharged from the tubular member 334 to the smoke pipe 333 and transported upward, thereby stably and evenly heating the coal char. The tubular member 334 includes but is not limited to being made of heat-resistant steel.

[0112] In an illustrative embodiment, an air inlet 3313 for allowing the gasification agent to enter is disposed at the bottom of the air chamber, and the air inlet 3313 is disposed parallel to and opposite to the smoke outlet 339 and the burner 32 .

[0113] Figure 5 A partial cross-sectional view of a combustor according to an embodiment of the present disclosure is schematically shown.

[0114] According to an embodiment of the present disclosure, as shown in the figure, each burner 32 includes a central channel 321, a gas fuel channel 322, a solid fuel channel 323 and a combustion-supporting channel 324. The central channel 321 is suitable for providing primary air or oxygen into the tubular member 334. The gas fuel channel 322 is arranged at the periphery of the central channel 321, and is suitable for conveying gas fuel (for example, pyrolysis oil gas from a pyrolysis reactor) into the tubular member 334, so that the gas fuel and the primary air or oxygen are preliminarily burned at the end of the nozzle. The solid fuel channel 323 is arranged at the periphery of the gas fuel channel 322, and is suitable for conveying solid fuel into the tubular member 334. The combustion-supporting channel 324 is arranged at the periphery of the solid fuel channel 323, and is suitable for conveying secondary air or oxygen into the tubular member 334, so as to mix with the solid fuel under the temperature environment provided by the preliminary combustion, and fully burn to provide flue gas. Among them, both the primary oxygen and the secondary oxygen can be oxygen generated from the water electrolysis unit.

[0115] In an alternative embodiment, the combustion of the fuel may be performed inside the burner 32 , and the high-temperature flue gas generated by the burner 32 may be sprayed into the tubular member 334 .

[0116] In such an embodiment, the tubular member 334 introduces the high-temperature flue gas into the flue duct 333. The high-temperature flue gas rises in the flue duct 333, enters the external flue 337 through the pipe member 338, and is discharged from the flue outlet 339. During the movement of the high-temperature flue gas, the heat is diffused into the containing space 3314 through the walls of the flue duct 333 and the external flue 337 on both sides of the containing space 3314. The multi-faceted radiation heat transfer method increases the heat transfer area, improves the heat supply per unit time, and reduces the lateral heat transfer radius between the gasification raw material and the heat source in the containing space 3314, thereby ensuring the radiation intensity of the heat source and being able to provide timely and stable heat for the gasification process.

[0117] In an illustrative embodiment, the burner 32 may be cylindrical, with a diameter of 200 to 400 mm, and adopts a four-channel design, including a central channel 321, a gas fuel channel 322, a solid fuel channel 323, and a combustion-supporting channel 324 from the inside to the outside. The width of each channel may be 10 to 50 mm in a circular ring shape. The nozzles at the end of the three outer channels narrow toward the central channel 321, forming a horizontal angle of 10 to 30 degrees, and each end of the channel (the end close to the tubular member 334) is protected by a cooling water jacket. The gas fuel is initially burned with the primary air / oxygen at the nozzle at the end of the burner 32 (the end extending into the tubular member 334), and then the solid fuel is fully burned with the secondary air / oxygen in the tubular member 334 to produce high-temperature flue gas.

[0118] In an illustrative embodiment, the flue gas outlet 339 is located below the burner 32, and the flue gas outlet 339 is arranged parallel to the burner 32. The waste flue gas is discharged from the flue gas outlet 339 after heat exchange, and the heat carried by the waste flue gas can be reused downstream through waste heat utilization methods such as heat exchangers and dryers.

[0119] According to an embodiment of the present disclosure, the staged gasification unit 3 further includes a dryer (not shown in the figure). The dryer is suitable for drying the raw coal.

[0120] According to the coal decoupled gasification and solar energy frequency division utilization complementary hydrogen production system of the embodiment of the present disclosure, the ultra-high temperature conventional gasification is decoupled into milder coal pyrolysis and coal coke gasification, and the solar energy frequency division technology is used to decouple solar thermal and photovoltaic, so that solar thermal and pyrolysis are matched, and photovoltaic and gasification are matched, thus realizing the complementary utilization of coal and renewable energy. After simulation calculation, the hydrogen production efficiency of this system can be improved by 11% compared with traditional gasification.

[0121] In an illustrative embodiment, raw coal in the form of 0-30 mm granules or 30-80 mm blocks is sent to the pyrolysis reactor 31 of the coal classification gasification unit 3 to receive heat energy provided by the long-wave portion of sunlight. The discharge speed of the spiral discharger 314 is controlled to ensure the residence time (30 minutes) required for coal pyrolysis. The long-wave portion of sunlight irradiates the coal blocks through the aperture. After simulation calculation, the temperature of the coal blocks can reach 950°C, which fully matches the pyrolysis temperature.

[0122] The coal undergoes pyrolysis reaction in the pyrolysis reactor 31 under air-tight conditions. The coal pyrolysis process generates solid semi-coke and gaseous pyrolysis gas containing coal tar in a high-temperature state. The pyrolysis gas is burned in the burner 32 with oxygen-enriched gas together with part of the CO produced by the gasification reactor 33 and the oxygen produced by the water electrolysis unit 2 to generate high-temperature flue gas. After heat recovery and cooling, the high-temperature flue gas is dehydrated to obtain high-concentration CO2 gas. The high-concentration CO2 is sent downstream to be converted into chemicals through chemical reactions or injected into the underground for storage through compression.

[0123] The coal char obtained after coal pyrolysis undergoes a gasification reaction with CO2 gas in the gasification reactor 33 to produce CO gas. Part of the CO gas from the gasification reactor 33 undergoes a water-gas shift reaction with water in the water-gas shift unit 4 under the action of a catalyst to produce CO2 and H2. The reaction equation of the water-gas shift is:

[0124] CO+H2O=CO2+H2.

[0125] The high temperature CO2 is partially circulated back to the gasification reactor 33 to react with the coal char again, and the amount of CO2 returned to the gasification reactor 33 is controlled by a high temperature resistant valve. The H2 generated by the water gas shift unit 4 and the H2 generated by the water electrolysis unit 2 are stored by the storage unit 5.

[0126] The sunlight is concentrated by the focusing assembly, and the short-wavelength sunlight is decoupled by the frequency divider, converted into electrical energy by the gallium arsenide photovoltaic cell, and then transmitted to the water electrolysis unit (for example, the electrolyzer). The electrolyzer is mainly composed of a protective plate, a plate, a contact electrode plate, a diffusion layer, a membrane electrode and other components. The generated O2 is discharged from the electrolyte outlet on the anode side, and the H2 is discharged from the electrolyte outlet on the cathode side.

[0127] The storage unit 5 stores hydrogen for use by downstream industries.

[0128] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A hydrogen production system combining coal decoupling gasification and solar energy frequency division utilization, characterized in that: include: A solar energy frequency division and utilization unit is used to decouple sunlight into a long-wave portion and a short-wave portion according to wavelength, so as to generate electricity by utilizing the short-wave portion; A water electrolysis unit, adapted to electrolyze water under the action of the electrical energy to produce hydrogen and oxygen; a staged gasification unit adapted to gasify externally supplied coal under heat provided by the long-wave portion to produce carbon monoxide; a water-gas shift unit adapted to perform water-gas shift on the carbon monoxide from the staged gasification unit and water from the outside to produce hydrogen and carbon dioxide, wherein at least a portion of the carbon dioxide is transported to the staged gasification unit as the gasifying agent; as well as The storage unit is suitable for storing the hydrogen generated by the water electrolysis unit and the water vapor conversion unit.

2. The hydrogen production system according to claim 1, characterized in that: The staged gasification unit comprises: A pyrolysis reactor, adapted to pyrolyze the coal under the heat provided by the long-wave portion to produce coal char and pyrolysis gas; a burner adapted to burn the pyrolysis gas from the pyrolysis reactor under the action of oxygen from the water electrolysis unit to generate flue gas; The gasification reactor, under the heat provided by the flue gas generated by the burner, causes the coal char from the pyrolysis reactor to undergo a gasification reaction with the gasification agent to generate carbon monoxide.

3. The hydrogen production system according to claim 2, characterized in that: The pyrolysis reactor comprises: The reaction tube is divided into a feeding zone, a pyrolysis zone and a discharging zone from top to bottom; A heat-insulating layer, at least arranged on the periphery of the pyrolysis zone; A solar collector irradiates the long-wave portion to the pyrolysis zone through the heat insulation layer, so that the temperature of the coal entering the pyrolysis zone from the feed zone is increased, a pyrolysis reaction occurs, and the coal char and the pyrolysis gas are produced; a spiral discharger, disposed in the discharge zone, adapted to discharge the coal char and the pyrolysis gas from the reaction tube and control the residence time of the coal in the pyrolysis zone; and The solid-gas separator is adapted to separate the coal char from the pyrolysis gas, transport the coal char to a gasification reactor, and transport the pyrolysis gas to the burner.

4. The hydrogen production system according to claim 3, characterized in that: The pyrolysis reactor also includes: A temperature detection device, adapted to obtain the real-time temperature of the pyrolysis zone; Wherein, the screw feeder is configured to control the residence time of the coal according to the real-time temperature to ensure complete pyrolysis of the coal.

5. The hydrogen production system according to claim 2, characterized in that: The gasification reactor comprises: A furnace body, forming a containing space inside; an outer furnace wall, arranged outside the furnace body and forming an outer flue with the furnace body; and A smoke duct is vertically installed in the accommodation space, and the upper part of the smoke duct is connected with the external flue through a pipe fitting; Among them, the burner is installed on the furnace body and is located below the flue gas duct, and is suitable for providing the flue gas to the flue gas duct from the bottom. The flue gas rises in the flue gas duct to heat the coal char flowing downward and the carbon dioxide flowing upward in the accommodating space, so that the coal char undergoes a gasification reaction, and the cooled flue gas is discharged through the external flue.

6. The hydrogen production system according to claim 5, characterized in that: The furnace body also includes: a feed pipe, passing through the outer furnace wall and installed on the top of the furnace body to communicate with the accommodation space, wherein the coal enters the accommodation space through the feed pipe; The flue gas duct is located below the feed duct, and the top of the flue gas duct is configured to be conical, so that the coal char falling on the top of the flue gas duct is evenly dispersed in the accommodation space.

7. The hydrogen production system according to claim 5, characterized in that: The gasification reactor further comprises: A tubular member extending in a horizontal direction and arranged below the flue gas duct and communicating with the flue gas duct, wherein the tubular member penetrates two opposite sides of the furnace body to guide the flue gas into the flue gas duct; There are two burners, which are symmetrically arranged at two axial ends of the tubular member to provide the flue gas by burning fuel.

8. The hydrogen production system according to claim 5, characterized in that: The bottom of the furnace body is provided with a discharge port, and the discharge port is suitable for allowing the ash generated by the coal char after the gasification reaction to be discharged; The furnace body also includes: An air distribution plate is obliquely installed between the periphery of the discharge port and the furnace body, so that an air chamber adjacent to the accommodation space is formed between the air distribution plate and the bottom wall and side wall of the furnace body; Among them, the carbon dioxide from the water vapor conversion unit enters the air chamber from the air inlet located at the lower part of the air chamber, and enters the containing space through multiple through holes on the air distribution plate, contacts the coal char in the containing space, and makes the ash falling on the air distribution plate be discharged through the discharge port.

9. The hydrogen production system according to any one of claims 5 to 8, characterized in that: Baffles are arranged in the smoke duct and the outer smoke duct, so that the smoke flows along a serpentine path in the smoke duct and the outer smoke duct.

10. The hydrogen production system according to claim 1, characterized in that: The solar energy frequency division utilization unit comprises: A light-collecting assembly, adapted to collect the sunlight; A frequency divider, adapted to decouple the sunlight into the long-wave portion and the short-wave portion according to wavelength; and Photovoltaic panels are suitable for converting said shortwave portion into electrical energy.

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