Integrated apparatus for hydrogen production by methane reforming and carbon capture and control method thereof

Abstract

The application relates to the technical field of methane hydrogen production equipment, and proposes methane reforming hydrogen production and carbon capture integrated equipment and a control method thereof. The methane reforming hydrogen production and carbon capture integrated equipment comprises a reforming reactor which is internally filled with a methane reforming catalyst and a calcium oxide adsorbent; the reforming reactor has a hydrogen production mode and an adsorbent regeneration mode; a steam generator is in communication with a steam inlet of the reforming reactor; a methane inlet pipeline is in communication with a methane inlet of the reforming reactor; a condenser is used for condensing and dehumidifying hydrogen-rich synthesis gas output by the reforming reactor in the hydrogen production mode to obtain hydrogen products; and a carbon dioxide circulation loop is started only in the adsorbent regeneration mode, and an inlet of the carbon dioxide circulation loop is in communication with a gas circulation outlet of the reforming reactor, and an outlet of the carbon dioxide circulation loop is in communication with a gas circulation inlet of the reforming reactor. The integrated equipment completes carbon dioxide capture while outputting high-purity hydrogen products, and promotes the development of hydrogen production technology in the direction of low carbon.

Description

Technical Field

[0001] This application relates to the field of methane hydrogen production equipment technology, and more specifically, to an integrated equipment for methane reforming hydrogen production and carbon capture and its control method. Background Technology

[0002] Hydrogen energy, as a clean and efficient secondary energy source, is becoming an important tool for reducing carbon dioxide emissions and achieving carbon neutrality. In the hydrogen energy industry chain, hydrogen production technology is the core link that determines the quality of the entire industry's development.

[0003] Currently, fossil fuel-based hydrogen production technologies still dominate. Natural gas-based blue hydrogen technologies, due to their economic advantages and technological maturity, are considered a realistic and feasible solution for the transition from gray hydrogen to green hydrogen at this stage. Among these, steam methane reforming (SMR) is the most widely used. However, this technology still faces inherent drawbacks such as high energy consumption and high carbon emission intensity, hindering the clean transformation of hydrogen production.

[0004] Therefore, there is an urgent need to develop a new type of hydrogen production equipment that can effectively reduce energy consumption and carbon emissions while ensuring hydrogen production efficiency, in order to overcome the above-mentioned shortcomings of existing SMR technology and promote the development of hydrogen production technology towards a low-carbon direction. Summary of the Invention

[0005] To address at least one of the aforementioned technical problems, the first aspect of this application proposes an integrated equipment for methane reforming to produce hydrogen and capture carbon.

[0006] The second aspect of this application proposes a control method for an integrated equipment for methane reforming to produce hydrogen and carbon capture.

[0007] In view of this, this application proposes an integrated equipment for methane reforming to produce hydrogen and capture carbon, comprising: a reforming reactor, internally filled with a methane reforming catalyst and a calcium oxide adsorbent; the reforming reactor has a hydrogen production mode and an adsorbent regeneration mode, wherein in the hydrogen production mode, the introduced steam and methane undergo a reforming reaction to produce hydrogen, and the carbon dioxide produced by the reaction is adsorbed in situ by the calcium oxide adsorbent; in the adsorbent regeneration mode, the calcium carbonate produced by the reaction is decomposed into calcium oxide and carbon dioxide; a steam generator, the outlet of which is connected to the steam inlet of the reforming reactor, for supplying steam to the reforming reactor; and a methane inlet pipeline, connected to the reforming reactor... The reactor is connected to the methane inlet to supply methane gas to the reforming reactor; the condenser, whose inlet is connected to the syngas outlet of the reforming reactor, is used to condense and dehumidify the hydrogen-rich syngas output from the reforming reactor in hydrogen production mode to obtain hydrogen product; the carbon dioxide circulation loop is only activated in the adsorbent regeneration mode, with its inlet connected to the gas circulation outlet of the reforming reactor and its outlet connected to the gas circulation inlet of the reforming reactor; the carbon dioxide circulation loop is used to recycle the carbon dioxide gas released by the decomposition of calcium carbonate in the reforming reactor and send it back to the reforming reactor to maintain the adsorbent regeneration reaction.

[0008] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a steam heat exchanger, installed on the pipeline between the syngas outlet of the reforming reactor and the condenser, and connected to the steam transport pipeline from the steam generator to the reforming reactor via a heat exchange pipeline, for recovering waste heat from the hydrogen-rich syngas to preheat the steam entering the reforming reactor.

[0009] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a water storage tank containing pure water and having an outlet; a feed pump whose inlet is connected to the outlet of the water storage tank and whose outlet is connected to the inlet of the steam generator; and a steam heater installed on the pipeline between the steam outlet of the steam generator and the steam inlet of the reforming reactor for heating the steam output from the steam generator.

[0010] In conjunction with the first aspect, in some feasible embodiments, the carbon dioxide circulation loop includes: a first control valve, the inlet of which is connected to the gas circulation outlet of the reforming reactor; a carbon dioxide cooler, the inlet of which is connected to the outlet of the first control valve, for cooling the discharged high-temperature carbon dioxide gas; a carbon dioxide induced draft fan, the inlet of which is connected to the outlet of the carbon dioxide cooler, for conveying the cooled carbon dioxide gas; and a carbon dioxide heater, the inlet of which is connected to the outlet of the carbon dioxide induced draft fan, and the outlet of which is connected to the gas circulation inlet of the reforming reactor, for electrically heating the cooled carbon dioxide gas before sending it back to the reforming reactor.

[0011] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a first wire mesh demister connected to the gas outlet of the condenser for filtering out residual moisture in the hydrogen-rich synthesis gas; a hydrogen conveying fan connected to the gas outlet of the first wire mesh demister for conveying hydrogen products; a second wire mesh demister connected to the gas outlet of the carbon dioxide cooler for filtering out moisture entrained in the carbon dioxide gas, the gas outlet of the second wire mesh demister being connected to the inlet of the carbon dioxide induced draft fan; wherein the outlets of the first and second wire mesh demisters are connected to a water storage tank.

[0012] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a gas concentration detection device, installed at the syngas outlet of the reforming reactor, used to monitor the concentrations of hydrogen, methane, carbon monoxide and carbon dioxide to determine the saturation state of the calcium oxide adsorbent.

[0013] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capture carbon also includes: a chiller unit, wherein the cooling medium outlet of the chiller unit is connected to the low-temperature side inlet of the condenser and the cooling channel inlet of the reforming reactor cover, respectively, for providing cooling medium to the condenser to condense water vapor in the hydrogen-rich synthesis gas and for cooling the cover of the reforming reactor.

[0014] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a recovery water tank, the inlet of which is connected to the outlet of the condenser and the outlet of the cooling channel of the reforming reactor cover, for the purpose of recovering cooling water.

[0015] In conjunction with the first aspect, in some feasible embodiments, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a methane heater, installed on the methane inlet pipeline, for heating the methane gas entering the reforming reactor; and a second control valve, installed on the methane inlet pipeline, for opening or closing the methane inlet pipeline.

[0016] The second aspect of this application proposes a control method for an integrated equipment for methane reforming to produce hydrogen and capturing carbon, comprising the following steps: Hydrogen production steps: Water vapor and methane are introduced into a fixed-bed reforming reactor filled with methane reforming catalyst and calcium oxide adsorbent to cause a reforming reaction to generate hydrogen. At the same time, the carbon dioxide generated by the reaction is adsorbed in situ by the calcium oxide adsorbent, and hydrogen-rich syngas is output from the outlet of the reforming reactor. Status monitoring steps: Monitor the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide in the syngas outlet gas of the reforming reactor to determine the saturation state of the calcium oxide adsorbent. Switching steps: When the concentration of carbon-containing gas exceeds the preset threshold or the concentration of hydrogen is lower than the preset threshold, the methane inlet is shut off, and water vapor continues to be introduced to flush the reforming reactor. Regeneration steps: After flushing, start the carbon dioxide circulation loop, heat the carbon dioxide gas and pass it into the reforming reactor to decompose the calcium carbonate in the reforming reactor into calcium oxide and carbon dioxide, thereby regenerating the calcium oxide adsorbent. The carbon dioxide generated during regeneration is then recycled back to the reforming reactor to maintain the regeneration reaction.

[0017] Compared with related technologies, this application has the following technical advantages: The integrated equipment for methane reforming hydrogen production and carbon capture provided in this application includes a reforming reactor, a steam generator, a methane inlet pipeline, a condenser, and a carbon dioxide circulation loop. Based on the fixed-bed principle, this equipment uses CaO as the carbon capture adsorbent. The catalyst and CaO adsorbent are pre-filled inside the reforming reactor. Continuous operation is achieved through alternating hydrogen production and adsorbent regeneration modes. While outputting high-purity hydrogen, it simultaneously captures CO2, meeting the demands of continuous industrial production. It also optimizes system thermal integration to a certain extent, enabling low-carbon hydrogen production based on natural gas.

[0018] This application addresses the existing problems of SMR hydrogen production technology by proposing an integrated equipment for continuous hydrogen production and carbon capture using methane reforming. This hydrogen production equipment can simultaneously output high-purity hydrogen and capture CO2. The hydrogen product concentration can reach 90 vol% or higher, and the carbon capture rate can reach 75% or higher.

[0019] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0020] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 A schematic diagram of an integrated equipment for methane reforming to produce hydrogen and capturing carbon is shown in one embodiment of this application; Figure 2 A schematic flowchart of the control method for an integrated equipment for methane reforming to produce hydrogen and capturing carbon, according to one embodiment of this application, is shown.

[0021] in, Figure 1 The correspondence between the reference numerals and component names in the attached drawings is as follows: 100 Reformer, 110 Steam Generator, 112 Steam Heat Exchanger, 114 Water Storage Tank, 116 Feed Pump, 118 Steam Heater, 120 Condenser, 130 Cold Water Tank, 132 Carbon Dioxide Exhaust Fan, 134 Carbon Dioxide Heater, 140 Chiller Unit, 150 Methane Heater, 160 Recycled Water Tank, 170 First Wire Mesh Demister, 172 Second Wire Mesh Demister, 180 First Filter, 182 Second Filter. Detailed Implementation

[0022] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0024] The following reference Figure 1 and Figure 2 This application describes an integrated equipment and control method for methane reforming hydrogen production and carbon capture, as well as some embodiments thereof.

[0025] like Figure 1 As shown, the first aspect of this application provides an integrated equipment for methane reforming to produce hydrogen and capture carbon, comprising: a reforming reactor 100, internally filled with a methane reforming catalyst and a calcium oxide adsorbent; the reforming reactor 100 has a hydrogen production mode and an adsorbent regeneration mode, wherein in the hydrogen production mode, the introduced water vapor and methane undergo a reforming reaction to generate hydrogen, and the carbon dioxide generated by the reaction is adsorbed in situ by the calcium oxide adsorbent; in the adsorbent regeneration mode, the calcium carbonate generated by the reaction is decomposed into calcium oxide and carbon dioxide; a steam generator 110, the outlet of which is connected to the steam inlet of the reforming reactor 100, for supplying water vapor to the reforming reactor 100; and a methane inlet pipeline connected to the reforming reactor 100. The methane inlet of reactor 100 is connected to supply methane gas to the reformer 100; the condenser 120, whose inlet is connected to the synthesis gas outlet of the reformer 100, is used to condense and dehumidify the hydrogen-rich synthesis gas output from the reformer 100 in hydrogen production mode to obtain hydrogen product; the carbon dioxide circulation loop, which is only activated in the adsorbent regeneration mode, has its inlet connected to the gas circulation outlet of the reformer 100 and its outlet connected to the gas circulation inlet of the reformer 100; the carbon dioxide circulation loop is used to recycle and process the carbon dioxide gas released from the decomposition of calcium carbonate in the reformer 100 and send it back to the reformer 100 to maintain the adsorbent regeneration reaction.

[0026] The integrated equipment for methane reforming to produce hydrogen and capture carbon provided in this application includes a reforming reactor 100, a steam generator 110, a methane inlet pipeline, a condenser 120, and a carbon dioxide circulation loop. The methane inlet pipeline is used to supply methane gas to the reforming reactor 100, and the steam generator 110 is used to supply steam to the reforming reactor 100.

[0027] This equipment integrates the reforming hydrogen production reaction and in-situ carbon dioxide capture into the same reforming reactor 100, and achieves the recycling and reuse of hydrogen production and calcium oxide adsorbent through dual-mode switching between hydrogen production mode and adsorbent regeneration mode. In hydrogen production mode, while the reforming reaction generates hydrogen-rich syngas, the calcium oxide adsorbent in the reforming reactor 100 can capture carbon dioxide in situ from the syngas, converting it into calcium carbonate which remains in the reforming reactor 100. This eliminates the need for separate carbon capture devices and gas separation units in traditional processes, simplifying the system process and significantly reducing carbon capture costs. In adsorbent regeneration mode, CO2 gas heated by the carbon dioxide circulation loop is introduced into the reforming reactor 100 through the carbon dioxide circulation loop, causing the calcium carbonate to decompose into calcium oxide and carbon dioxide, restoring the adsorption activity of the adsorbent.

[0028] The equipment is equipped with a condenser 120, which can condense and dehumidify the high-temperature hydrogen-rich synthesis gas output from the hydrogen production stage to obtain high-purity hydrogen products. In the adsorbent regeneration mode, excess high-purity CO2-rich gas can also be output for other production needs.

[0029] The integrated equipment for methane reforming hydrogen production and carbon capture provided in this application enables the reforming reactor 100 to operate continuously through alternating operation of two modes, ensuring the long-term stable operation of the hydrogen production and carbon capture process, meeting the needs of continuous industrial production, and promoting the development of hydrogen production technology towards low-carbon directions.

[0030] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capture carbon further includes: a steam heat exchanger 112, which is installed on the pipeline between the syngas outlet of the reforming reactor 100 and the condenser 120, and is connected to the steam transmission pipeline between the steam generator 110 and the reforming reactor 100 through a heat exchange pipeline, for recovering waste heat in the hydrogen-rich syngas to preheat the steam entering the reforming reactor 100.

[0031] In this embodiment, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes a steam heat exchanger 112. By installing the steam heat exchanger 112 between the syngas outlet and the condenser 120, and connecting it to the steam delivery pipeline from the steam generator 110 to the reforming reactor 100 via a heat exchange pipeline, the waste heat from the hydrogen-rich syngas is recovered and utilized in stages. The hydrogen-rich syngas at the outlet of the reforming reactor 100 has a high temperature and carries a large amount of waste heat, which is usually directly lost in traditional processes. The steam heat exchanger 112 transfers this waste heat to the steam entering the reforming reactor 100, preheating the steam to a higher temperature before it enters the reforming reactor 100, reducing external energy input, thereby significantly improving the system thermal efficiency of the entire equipment and reducing the energy consumption and operating costs of the hydrogen production process. A second filter 182 is also installed on the pipeline between the syngas outlet of the reforming reactor 100 and the steam heat exchanger 112 for filtering the hydrogen-rich syngas.

[0032] Meanwhile, the temperature of the hydrogen-rich synthesis gas is reduced after the waste heat is recovered by the steam heat exchanger 112, and the temperature difference between it and the cooling medium is smaller when it enters the condenser 120. This is conducive to the efficient operation of the condensation and dehumidification process, reduces the cooling load of the condenser 120, and further reduces the system energy consumption. The two processes of steam heating and synthesis gas cooling, which originally required additional energy consumption, are coupled together through heat exchange, realizing the internal self-balance of energy, simplifying the configuration of external auxiliary equipment of the system, and improving the compactness and economy of the integrated equipment.

[0033] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capture carbon further includes: a water storage tank 114, which stores pure water and has an outlet; a water pump 116, whose inlet is connected to the outlet of the water storage tank 114 and whose outlet is connected to the inlet of the steam generator 110; and a steam heater 118, which is disposed on the pipeline between the steam outlet of the steam generator 110 and the steam inlet of the reforming reactor 100, for heating the steam output from the steam generator 110.

[0034] In this embodiment, the integrated equipment for methane reforming hydrogen production and carbon capture also includes a water storage tank 114, a feed water pump 116, and a steam heater 118. The water storage tank 114 stores pure water, and a first filter 180 is installed at the outlet of the tank. The feed water pump 116, in conjunction with the filter, stably delivers the filtered pure water to the steam generator 110, ensuring the water quality for the reforming reaction from the source. The methane reforming reaction has high requirements for water quality. Impurities such as metal ions and minerals in ordinary water can easily lead to catalyst poisoning and deactivation, or scaling and clogging of pipelines under high-temperature conditions. Using pure water as raw material effectively avoids the problems of catalyst activity reduction and equipment scaling, extending the service life of the catalyst and equipment. The feed water pump 116 provides a stable pressurized water supply to the steam generator 110, ensuring the steam generation rate of the steam generator 110 and the continuity of system operation, so that the hydrogen production process is not affected by fluctuations in water supply conditions.

[0035] like Figure 1 As shown, this application installs a steam heater 118 between the outlet of the steam generator 110 and the inlet of the reforming reactor 100 to reheat the steam output from the steam generator 110, thereby further increasing the steam temperature entering the reforming reactor 100. Methane steam reforming is a strongly endothermic reaction; a higher steam temperature is beneficial for promoting the forward reaction, improving methane conversion and hydrogen yield. The steam heater 118 and the aforementioned steam heat exchanger 112 form a complementary heat recovery relationship. The steam heat exchanger 112 recovers syngas waste heat to preheat the steam, while the steam heater 118 provides end-point supplemental heating for the steam. Together, they ensure that the steam entering the reforming reactor 100 reaches the optimal reaction temperature, maximizing the overall system thermal efficiency and hydrogen production performance.

[0036] like Figure 1 As shown, in some embodiments provided in this application, the carbon dioxide circulation loop includes: a first control valve, the inlet of which is connected to the gas circulation outlet of the reforming reactor 100; a carbon dioxide cooler, the inlet of which is connected to the outlet of the first control valve, for cooling the discharged high-temperature carbon dioxide gas; a carbon dioxide induced draft fan 132, the inlet of which is connected to the outlet of the carbon dioxide cooler, for conveying the cooled carbon dioxide gas; and a carbon dioxide heater 134, the inlet of which is connected to the outlet of the carbon dioxide induced draft fan 132, and the outlet of which is connected to the gas circulation inlet of the reforming reactor 100, for electrically heating the cooled carbon dioxide gas and then sending it back to the reforming reactor 100.

[0037] In this embodiment, the carbon dioxide circulation loop includes a first control valve, a carbon dioxide cooler, a carbon dioxide induced draft fan 132, and a carbon dioxide heater 134, achieving precise temperature control and directional circulation of carbon dioxide gas in the calcium oxide adsorbent regeneration mode. The carbon dioxide gas produced by calcium carbonate decomposition is at a high temperature; directly sending it back to the reforming reactor 100 would cause drastic temperature fluctuations within the reactor, which is detrimental to the stable regeneration reaction. The carbon dioxide cooler first cools the high-temperature carbon dioxide, preventing thermal damage to the induced draft fan and pipelines, while also reducing the gas volume and minimizing the power consumption of the induced draft fan. The first control valve enables precise start-stop control of the circulation loop, operating only in the adsorbent regeneration mode, thus avoiding ineffective interference from carbon dioxide in the hydrogen production mode.

[0038] This application installs a carbon dioxide heater 134 after the induced draft fan to electrically heat the cooled carbon dioxide gas before sending it back to the reforming reactor 100. This ensures that the temperature of the returned gas meets the thermodynamic conditions required for calcium carbonate decomposition. Calcium carbonate decomposition is an endothermic reaction requiring a continuously maintained high-temperature environment. The precisely temperature-controlled carbon dioxide recirculation gas, sent back to the reforming reactor 100, not only replenishes the atmosphere needed for the regeneration reaction but also helps maintain the reaction temperature through its own heat, which is beneficial for the complete decomposition of calcium carbonate and improves the regeneration efficiency of the calcium oxide adsorbent. This allows for a closed-loop, controllable circulation of carbon dioxide within the system, avoiding external carbon emissions. Furthermore, the electric heating method facilitates precise adjustment of the loop temperature, enhancing the flexibility and controllability of the equipment operation.

[0039] The carbon dioxide cooler can be a cold water tank 130.

[0040] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capturing carbon further includes: a first wire mesh demister 170, connected to the gas outlet of the condenser 120, for filtering out residual moisture in the hydrogen-rich synthesis gas; a hydrogen conveying fan, connected to the gas outlet of the first wire mesh demister 170, for conveying hydrogen products; a second wire mesh demister 172, connected to the gas outlet of the carbon dioxide cooler, for filtering out moisture entrained in the carbon dioxide gas, and the gas outlet of the second wire mesh demister 172 is connected to the inlet of the carbon dioxide induced draft fan 132; wherein the water outlets of the first wire mesh demister 170 and the second wire mesh demister 172 are connected to the water storage tank 114.

[0041] In this embodiment, the integrated equipment for methane reforming hydrogen production and carbon capture also includes a first wire mesh demister 170, a hydrogen conveying fan, and a second wire mesh demister 172. By installing the first wire mesh demister 170 at the outlet of the condenser 120 and configuring a hydrogen conveying fan after it, deep dehumidification and stable delivery of the hydrogen product are achieved. A small amount of mist-like moisture remains in the hydrogen-rich synthesis gas after preliminary dehumidification by the condenser 120. Direct delivery would result in substandard hydrogen purity, and moisture entering the hydrogen conveying fan could easily cause impeller corrosion and performance degradation. The first wire mesh demister 170 effectively filters out residual moisture, ensuring the purity and quality of the hydrogen product. Simultaneously, the second wire mesh demister 172 is connected to the outlet of the carbon dioxide cooler, performing secondary dehumidification on the cooled carbon dioxide gas. This prevents moisture from entering the reforming reactor 100 with the circulating gas, preventing interference with the temperature field within the reforming reactor 100 due to moisture evaporation, protecting the stable progress of the calcium carbonate decomposition reaction, and also preventing moisture from damaging the carbon dioxide induced draft fan 132.

[0042] This application achieves centralized recovery and recycling of condensate within the system by connecting the outlets of both the first wire mesh demister 170 and the second wire mesh demister 172 to a water storage tank 114. The water separated by the two wire mesh demisters flows through pipelines into the water storage tank 114, and is then pumped back into the steam generator 110 via a feedwater pump 116 to participate in steam production, forming a closed-loop water resource cycle. This reduces the consumption of external pure water and lowers operating costs. This design integrates gas purification and water recovery functions into the demister structure, eliminating the need for an additional water treatment unit, simplifying system configuration, and improving equipment integration and economy.

[0043] In some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capture carbon further includes: a gas concentration detection device, which is installed at the syngas outlet of the reforming reactor 100, for monitoring the concentrations of hydrogen, methane, carbon monoxide and carbon dioxide, in order to determine the saturation state of the calcium oxide adsorbent.

[0044] In this embodiment, by installing a gas concentration detection device at the syngas outlet of the reforming reactor 100, the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide are monitored in real time, enabling online and accurate determination of the saturation state of the calcium oxide adsorbent.

[0045] The gas concentration detection device can be a gas chromatograph, used to monitor key data such as hydrogen, methane, carbon monoxide, and carbon dioxide to determine the state of the calcium oxide adsorbent in the reactor. When the concentrations of carbon-containing gases such as CH4, CO, and CO2 in the product syngas remain at low levels, the adsorbent is considered to still possess adsorption capacity. As the system operates, when the concentration of carbon-containing gases in the product exceeds a specified value, most of the CaO adsorbent packed in the reactor has been converted to CaCO3, losing its carbon removal adsorption capacity. At this point, the system operation should switch from hydrogen production mode to calcium oxide adsorbent regeneration mode.

[0046] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capture carbon further includes: a chiller unit 140, the cooling medium outlet of the chiller unit 140 being connected to the low-temperature side inlet of the condenser 120 and the cooling channel inlet of the reforming reactor 100, respectively, for providing cooling medium to the condenser 120 to condense water vapor in the hydrogen-rich synthesis gas, and for cooling the cover of the reforming reactor 100.

[0047] In this embodiment, by simultaneously connecting the cooling medium outlet of the chiller unit 140 to both the low-temperature inlet of the condenser 120 and the cooling channel inlet of the reformer 100's cover, this application achieves dual-use of cooling resources and system integration. The chiller unit 140 provides a stable low-temperature cooling medium to the condenser 120, ensuring efficient condensation of water vapor in the hydrogen-rich synthesis gas and improving the dehumidification purity of the hydrogen product. Simultaneously, it eliminates the need for a separate cooling system for the condenser 120, reducing the number of devices and piping complexity, and lowering the overall equipment size and investment cost. The centralized supply of the cooling medium also facilitates unified control of the cooling temperature, ensuring the condensation process is always under optimal operating conditions.

[0048] In addition, the chiller unit 140 simultaneously cools the cover of the reforming reactor 100, effectively controlling the external temperature level of the reforming reactor 100. The reforming reaction takes place under high-temperature conditions, and prolonged exposure to high temperatures can easily lead to aging and failure of seals, leaks at flange connections, and other problems. The low-temperature medium in the cooling channel continuously removes heat from the cover, maintaining the external temperature of the reforming reactor 100 within a safe range, protecting the integrity of the sealing structure and external piping, preventing the thermal radiation impact on surrounding equipment, extending the service life of the equipment, and improving the safety and reliability of the system operation.

[0049] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes: a recovery water tank 160, the inlet of which is connected to the outlet of the condenser 120 and the outlet of the cooling channel of the reforming reactor 100, for recovering cooling water.

[0050] In this embodiment, the present application achieves simultaneous dual-path synchronous recovery of condensate and cooling water by simultaneously connecting the inlet of the recovery water tank 160 to the outlet of the condenser 120 and the outlet of the cooling channel of the reformer 100 cover. The condensate generated by the condenser 120 and the cooling water discharged from the cover cooling channel are both clean water sources. After being collected uniformly by the recovery water tank 160, they can be directly reused in the steam generator 110 to produce steam, avoiding water waste, reducing the need for external pure water replenishment, and reducing operating costs.

[0051] Meanwhile, the cooling water under the machine cover carries the residual heat of the machine cover of the reformer reactor 100. After mixing and recovering it with the condensate, it is sent to the steam generator 110, which can partially replace the external heating energy consumption and improve the overall thermal efficiency of the system.

[0052] like Figure 1 As shown in some embodiments provided in this application, the integrated equipment for methane reforming to produce hydrogen and capture carbon further includes: a methane heater 150, which is disposed on the methane inlet pipeline and is used to heat the methane gas entering the reforming reactor 100; and a second control valve, which is disposed on the methane inlet pipeline and is used to open or close the methane inlet pipeline.

[0053] In this embodiment, the integrated equipment for methane reforming to produce hydrogen and capturing carbon also includes a methane heater 150 and a second control valve. By installing the methane heater 150 on the methane inlet pipeline, the methane gas entering the reforming reactor 100 is preheated, effectively reducing the temperature rise load of the reforming reactor 100 and shortening the system start-up time. The preheated methane has a smaller temperature difference when it comes into contact with high-temperature steam, avoiding thermal shock to the catalyst bed caused by low-temperature methane and protecting the activity and structural integrity of the catalyst. At the same time, the higher feed temperature is conducive to the forward reforming reaction, improving the methane conversion rate and hydrogen yield, and enhancing the overall hydrogen production efficiency of the equipment.

[0054] A second control valve is installed on the methane inlet pipeline, enabling precise start-up and shutdown control of the methane supply path. In hydrogen production mode, the valve is opened to ensure a continuous methane supply; in adsorbent regeneration mode or when the system shuts down, the valve is closed to quickly cut off the methane source and prevent unreacted methane from entering the reformer 100 and causing safety hazards. The second control valve, in conjunction with the gas concentration detection device and the first control valve, forms a multi-level safety interlock and operating condition switching mechanism, giving the equipment flexible operational control capabilities and a high level of inherent safety.

[0055] like Figure 2 As shown, the second aspect of this application provides a control method for an integrated equipment for methane reforming to produce hydrogen and capturing carbon, comprising the following steps: S202: Hydrogen production step: Water vapor and methane are introduced into a fixed-bed reforming reactor filled with methane reforming catalyst and calcium oxide adsorbent to cause a reforming reaction to generate hydrogen. At the same time, the carbon dioxide generated by the reaction is adsorbed in situ by the calcium oxide adsorbent, and hydrogen-rich synthesis gas is output from the outlet of the reforming reactor. S204: Status monitoring steps: Monitor the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide in the syngas outlet gas of the reforming reactor to determine the saturation state of the calcium oxide adsorbent. S206: Switching step: When the concentration of carbon-containing gas exceeds the preset threshold or the concentration of hydrogen is lower than the preset threshold, the methane inlet is shut off, and water vapor continues to be introduced to flush the reforming reactor. S208: Regeneration Step: After flushing, start the carbon dioxide circulation loop, heat the carbon dioxide gas and pass it into the reforming reactor to decompose the calcium carbonate in the reforming reactor into calcium oxide and carbon dioxide, thereby regenerating the calcium oxide adsorbent. The carbon dioxide generated during regeneration is then recycled back to the reforming reactor to maintain the regeneration reaction.

[0056] The control method for the integrated equipment for methane reforming hydrogen production and carbon capture provided in this application achieves precise identification of the saturation state of the calcium oxide adsorbent and automatic control of the hydrogen production process through the coordinated operation of the hydrogen production step and the state monitoring step. In the hydrogen production stage, methane and water vapor undergo a reforming reaction under the action of a catalyst to generate hydrogen. The calcium oxide adsorbent captures the carbon dioxide produced in situ, allowing high-purity hydrogen-rich gas to be directly output from the syngas outlet, eliminating the need for subsequent additional decarbonization processes and simplifying the process flow. By monitoring the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide in the syngas outlet gas of the reforming reactor, it is possible to accurately determine whether the adsorbent has reached saturation without relying on time estimation or experience. When the concentration of carbon-containing gas exceeds a preset threshold or the hydrogen concentration falls below a preset threshold, the system automatically triggers a switch, avoiding hydrogen production loss due to premature regeneration of the adsorbent before saturation and preventing carbon dioxide penetration and hydrogen purity reduction caused by continued hydrogen production after the adsorbent has reached saturation, thus ensuring the continuity of the hydrogen production process and the stability of product quality.

[0057] This application achieves a smooth transition from hydrogen production mode to regeneration mode by shutting off the methane inlet and continuing to introduce steam for gas flushing during the switching process. After shutting off the methane inlet, there is no new carbon source input into the reforming reactor. The introduced steam gradually replaces and removes the unreacted methane remaining in the bed, while reducing the carbon load in the bed and creating favorable conditions for subsequent calcium carbonate decomposition. In addition, steam flushing avoids the thermal shock and structural damage to the catalyst bed caused by directly introducing high-temperature carbon dioxide gas, protecting the catalyst activity and the sealing integrity of the reforming reactor, enabling the equipment to maintain long-term stable operation during frequent hydrogen production-regeneration cycle switching.

[0058] This application achieves efficient adsorbent regeneration and a closed-loop carbon dioxide system by initiating a carbon dioxide circulation loop during the regeneration process. Heated carbon dioxide gas is introduced into the reforming reactor to decompose calcium carbonate, and the generated carbon dioxide is recycled back to maintain the regeneration reaction. This design eliminates the need for external regeneration media, utilizing the system's own generated carbon dioxide for regeneration, thus reducing operating costs and avoiding carbon emissions. The recycled carbon dioxide maintains a high-temperature atmosphere within the reforming reactor, which is conducive to the complete decomposition of calcium carbonate, improving the regeneration efficiency and cycle life of the calcium oxide adsorbent. This enables the equipment to operate with long cycles, low emissions, and high efficiency.

[0059] like Figure 1 As shown in the specific embodiment, the integrated equipment for methane reforming to produce hydrogen and capture carbon provided in this application includes a reforming reactor 100, a steam generator 110, a chiller unit 140 and its related circuits, a steam heat exchanger 112, a methane heater 150, a steam heater 118, a carbon dioxide heater 134, a carbon dioxide circulation circuit and related equipment, a condenser 120, a water storage system, and related testing equipment and pipelines.

[0060] In the aforementioned equipment, the reforming reactor 100, methane heater 150, steam heater 118, and carbon dioxide heater 134 are key components of the system. The system has two operating stages: an adsorption-enhanced methane reforming hydrogen production stage and a high-temperature calcination CaO regeneration stage. When high-temperature steam and methane gas enter the reforming reactor 100, an adsorption-enhanced methane steam reforming reaction occurs, where methane is reformed into syngas containing H2, CO, CO2, and steam. The CO content is low and does not affect the process. Subsequently, the adsorbent CaO adsorbs the CO2 in the syngas, converting it into CaCO3. The hydrogen-rich, low-carbon syngas after adsorption and carbon removal is transported to the condenser 120 for condensation and dehumidification before being output as a product. The condensate obtained from the condenser 120 is used for subsequent steam generation, saving water consumption. The chiller unit 140 is mainly used for cooling the low-temperature side of the condenser 120 and for cooling the cover of the reforming reactor 100, ensuring stable equipment operation. The steam heat exchanger 112 is used for heat recovery between the internal streams of the system, and to reuse the waste heat during the operation of the system to improve the thermal efficiency of the system.

[0061] The carbon dioxide circulation loop mainly consists of a cold water tank 130, a second wire mesh demister 172, a carbon dioxide induced draft fan 132, a carbon dioxide heater 134, and related pipelines and detection devices. Because the carbon dioxide induced draft fan 132 cannot operate normally under the predetermined high-temperature conditions, the cold water tank 130 is used to cool the high-temperature CO2 stream before it is circulated through the carbon dioxide induced draft fan 132. Each heating device is equipped with a heating resistance wire to heat methane, water vapor, and carbon dioxide, providing the necessary heat for the reforming reactor 100.

[0062] During the hydrogen production process, key data such as hydrogen and carbon dioxide concentrations in the product are monitored using devices such as gas chromatographs to determine the state of the CaO adsorbent in the reforming reactor 100. When the concentrations of carbon-containing gases such as CH4, CO, and CO2 in the product syngas remain at low levels, the adsorbent is considered to still possess adsorption capacity. As the system operates, when the concentration of carbon-containing gases in the product exceeds a specified value, most of the CaO adsorbent packed in the reforming reactor 100 has been converted to CaCO3, losing its carbon removal adsorption capacity. The system should then switch from hydrogen production to calcium oxide regeneration. During this change in system operation, the methane inlet is closed, while high-temperature steam is continuously fed into the reforming reactor 100 to flush it and remove excess gas. After a period of flushing, the steam supply is stopped, and the carbon dioxide circulation loop and its electric heater are activated, supplying high-temperature carbon dioxide gas into the reforming reactor 100. This causes the calcium carbonate to decompose under high temperature, generating carbon dioxide and calcium oxide, thus regenerating the adsorbent. When the relevant instruments detect that the CO2 concentration is at a certain value, it indicates that the calcination reaction is proceeding normally.

[0063] Compared with existing SMR hydrogen production technology, this integrated equipment for methane reforming hydrogen production and carbon capture has the following advantages: This integrated equipment enables continuous and convenient carbon capture during hydrogen production, significantly reducing carbon capture costs compared to traditional carbon capture and storage (CCUS) technology. Furthermore, the system can output excess high-purity CO2-rich gas to meet other production needs.

[0064] This integrated equipment will achieve hydrogen production and adsorbent calcination and regeneration in stages by regulating the stream flowing into the reforming reactor and its related temperature. Compared with circulating fluidized bed and dual fluidized bed reforming reactors, it simplifies the system structure, realizes the integration and miniaturization of the reforming reactor, reduces the cost of equipment production, installation, operation, and other related costs, and improves the system's economic efficiency.

[0065] Other supplementary notes: (1) Some of the CaO adsorbent will be deactivated during operation and will lose its function as the operating time increases, affecting product quality. Therefore, the reforming reactor should be equipped with a packing port and a discharge port to facilitate the packing process later.

[0066] (2) The chemical reactions mentioned above are the main reactions in each operation process. Other side chemical reactions are not considered.

[0067] (3) Considering the instability of hydrogen, explosion-proof measures are added to all key components and pipelines of the system to ensure safety during operation.

[0068] (4) When the accuracy of the carbon dioxide monitoring equipment is low and cannot meet the preset requirements, only the hydrogen concentration detection device can be used. The hydrogen concentration data is used to determine the condition of the packing material inside the reforming reactor and to determine when to carry out the adsorbent regeneration process.

[0069] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0070] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0071] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An integrated equipment for methane reforming to produce hydrogen and capturing carbon, characterized in that, include: The reforming reactor is filled with a methane reforming catalyst and a calcium oxide adsorbent. The reforming reactor has a hydrogen production mode and an adsorbent regeneration mode. In the hydrogen production mode, the introduced water vapor and methane undergo a reforming reaction to generate hydrogen, and the carbon dioxide produced by the reaction is adsorbed in situ by the calcium oxide adsorbent. In the adsorbent regeneration mode, the calcium carbonate produced by the reaction is decomposed into calcium oxide and carbon dioxide. A steam generator, the outlet of which is connected to the steam inlet of the reforming reactor, is used to supply steam to the reforming reactor; A methane inlet pipeline is connected to the methane inlet of the reforming reactor and is used to supply methane gas to the reforming reactor. A condenser, the inlet of which is connected to the syngas outlet of the reforming reactor, is used to condense and dehumidify the hydrogen-rich syngas output from the reforming reactor in hydrogen production mode to obtain hydrogen product. A carbon dioxide circulation loop is provided, which is activated only in the adsorbent regeneration mode. Its inlet is connected to the gas circulation outlet of the reforming reactor, and its outlet is connected to the gas circulation inlet of the reforming reactor. The carbon dioxide circulation loop is used to circulate and process the carbon dioxide gas released by the decomposition of calcium carbonate in the reforming reactor and send it back to the reforming reactor to maintain the adsorbent regeneration reaction.

2. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 1, characterized in that, Also includes: A steam heat exchanger is installed on the pipeline between the syngas outlet of the reforming reactor and the condenser, and is connected to the steam transport pipeline between the steam generator and the reforming reactor through a heat exchange pipeline. It is used to recover waste heat from the hydrogen-rich syngas to preheat the steam entering the reforming reactor.

3. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 2, characterized in that, Also includes: A water storage tank containing pure water, the water storage tank having a water outlet; A water pump, the inlet of which is connected to the outlet of the water storage tank, and the outlet of which is connected to the inlet of the steam generator; A steam heater is installed on the pipeline between the steam outlet of the steam generator and the steam inlet of the reforming reactor for heating the steam output from the steam generator.

4. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 3, characterized in that, The carbon dioxide cycle loop includes: The first control valve has its inlet connected to the gas circulation outlet of the reforming reactor; A carbon dioxide cooler, the inlet of which is connected to the outlet of the first control valve, is used to cool the discharged high-temperature carbon dioxide gas. A carbon dioxide induced draft fan, the inlet of which is connected to the outlet of the carbon dioxide cooler, is used to transport cooled carbon dioxide gas; A carbon dioxide heater, whose inlet is connected to the outlet of the carbon dioxide induced draft fan and whose outlet is connected to the gas circulation inlet of the reforming reactor, is used to electrically heat the cooled carbon dioxide gas and then send it back to the reforming reactor.

5. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 4, characterized in that, Also includes: The first wire mesh demister is connected to the gas outlet of the condenser and is used to filter out residual moisture in the hydrogen-rich synthesis gas. A hydrogen conveying fan is connected to the gas outlet of the first wire mesh demister and is used to convey hydrogen products. The second wire mesh demister is connected to the gas outlet of the carbon dioxide cooler and is used to filter out moisture entrained in the carbon dioxide gas. The gas outlet of the second wire mesh demister is connected to the inlet of the carbon dioxide induced draft fan. The outlets of the first and second wire mesh demisters are connected to the water storage tank.

6. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 1, characterized in that, Also includes: A gas concentration detection device is installed at the syngas outlet of the reforming reactor to monitor the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide to determine the saturation state of the calcium oxide adsorbent.

7. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 1, characterized in that, Also includes: The chiller unit has its cooling medium outlet connected to the low-temperature side inlet of the condenser and the cooling channel inlet of the reforming reactor cover, respectively. It is used to provide cooling medium to the condenser to condense water vapor in the hydrogen-rich synthesis gas and to cool the cover of the reforming reactor.

8. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to claim 7, characterized in that, Also includes: A recovery water tank, the inlet of which is connected to the outlet of the condenser and the outlet of the cooling channel of the reforming reactor, is used to recover cooling water.

9. The integrated equipment for methane reforming to produce hydrogen and capturing carbon according to any one of claims 1 to 8, characterized in that, Also includes: A methane heater is installed on the methane inlet pipe to heat the methane gas entering the reforming reactor. The second control valve is installed in the methane inlet pipeline and is used to open or close the methane inlet pipeline.

10. A control method for an integrated equipment for methane reforming hydrogen production and carbon capture as described in any one of claims 1 to 9, characterized in that, Includes the following steps: Hydrogen production steps: Water vapor and methane are introduced into a fixed-bed reforming reactor filled with methane reforming catalyst and calcium oxide adsorbent to cause a reforming reaction to generate hydrogen. At the same time, the carbon dioxide generated by the reaction is adsorbed in situ by the calcium oxide adsorbent, and hydrogen-rich syngas is output from the outlet of the reforming reactor. Status monitoring steps: Monitor the concentrations of hydrogen, methane, carbon monoxide, and carbon dioxide in the syngas outlet gas of the reforming reactor to determine the saturation state of the calcium oxide adsorbent. Switching steps: When the concentration of carbon-containing gas exceeds the preset threshold or the concentration of hydrogen is lower than the preset threshold, the methane inlet is shut off, and water vapor continues to be introduced to flush the reforming reactor. Regeneration steps: After flushing, start the carbon dioxide circulation loop, heat the carbon dioxide gas and pass it into the reforming reactor to decompose the calcium carbonate in the reforming reactor into calcium oxide and carbon dioxide, thereby regenerating the calcium oxide adsorbent. The carbon dioxide generated during regeneration is then recycled back to the reforming reactor to maintain the regeneration reaction.

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