A comprehensive utilization system for H2 and CO co-production based on coal spontaneous combustion and blast furnace tail gas recycling.

Abstract

This application discloses a comprehensive utilization system based on the co-production of H2 and CO from coal spontaneous combustion and blast furnace tail gas recycling. The system includes a controlled coal spontaneous combustion reaction and hydrocarbon collection unit, a hydrocarbon gas catalytic cracking hydrogen production unit, a hydrogen compression and storage and blast furnace hydrogen-rich injection unit, a blast furnace gas purification and component separation and blending unit, and a central intelligent control and optimization platform. These components are connected via pipelines to form a closed-loop material circulation system: directional hydrocarbon production from coal spontaneous combustion – hydrogen production from hydrocarbon cracking – hydrogen-rich blast furnace smelting – tail gas return to the coal bed. By adjusting the ratio of inert gas to air, a low-temperature pyrolysis environment is created to achieve a high hydrocarbon production mode. High-purity hydrogen is produced through catalytic cracking and used for blast furnace injection, reducing coke ratio and carbon emissions. Simultaneously, blast furnace gas is separated to obtain CO-rich gas and inert gas; the former is used in the blast furnace or chemical industry, while the latter is reinjected into the coal bed to regulate reaction intensity. This application realizes the transformation of coal spontaneous combustion from a safety hazard to a controllable resource, supporting cross-system material closed-loop and low-carbon synergistic operation.

Description

Technical Field

[0001] This application relates to the interdisciplinary fields of energy, metallurgy and mine safety, and in particular to a comprehensive utilization system and method based on the co-production of H2 and CO from coal spontaneous combustion and blast furnace tail gas recycling. Background Technology

[0002] As the main energy source in my country's energy system, the safe, efficient development and clean utilization of coal are core elements in ensuring national energy security. Spontaneous combustion of coal (SCC) is one of the most frequent major disasters during coal mining and storage. It not only causes the burning and loss of large amounts of coal resources and triggers major safety accidents such as underground fires and gas explosions, but also continuously emits large amounts of greenhouse gases and toxic and harmful gases into the atmosphere, leading to serious ecological and environmental problems. Currently, the industry's control of coal spontaneous combustion mainly relies on passive prevention and control technologies. Mainstream technologies include conventional methods such as grouting fire extinguishing, inert gas injection, and sealing of air leaks. Although these methods can suppress the development of coal spontaneous combustion to a certain extent, they have drawbacks such as high control costs, poor sustainability of prevention and control, and inability to fundamentally change the uncontrollable nature of coal spontaneous combustion. More importantly, during the low-temperature pyrolysis and oxidation process of coal spontaneous combustion, gas resources rich in low-carbon hydrocarbons such as ethane and propane are continuously released. Existing prevention and control technologies completely ignore the high-value-added resource utilization of these hydrocarbon gases, failing to transform the disaster process of coal spontaneous combustion into a controllable resource production process, resulting in a large waste of resources and failing to achieve the synergistic unity of disaster prevention and control and resource utilization.

[0003] The steel industry is a vital pillar of my country's national economy, and blast furnace ironmaking, as the core process in steel production, is a key unit for carbon emissions and energy consumption in my country's industrial sector. Its carbon emissions account for over 70% of the total carbon emissions from the entire steel industry process, making it a crucial link in achieving the steel industry's "dual carbon" goals. The blast furnace ironmaking process produces a large amount of blast furnace gas (BFG), which is rich in components such as CO, CO2, and N2. Currently, blast furnace gas is mostly used as a low-calorific-value fuel for boiler combustion and power generation within the plant. This not only results in low energy efficiency but also leads to the direct emission of CO2 from the gas, exacerbating the greenhouse effect. Furthermore, the high-value CO component in the gas has not been efficiently purified and precisely utilized. In recent years, hydrogen-rich injection technology for blast furnaces has received widespread attention in the industry as one of the core technologies for reducing carbon emissions in blast furnace ironmaking. This technology injects hydrogen into the blast furnace to replace fossil fuels such as coke and pulverized coal. At the same time, it utilizes the strong reducing properties of hydrogen to enhance the reduction process of iron oxides, which can effectively reduce the coke ratio and carbon emission intensity of the blast furnace. However, the large-scale promotion and application of this technology has always been limited by the industry pain points of high production costs and difficulty in stable supply of clean hydrogen.

[0004] Currently, although some research has explored coal-to-hydrogen technology and blast furnace hydrogen-rich injection carbon reduction technology, and some technical solutions have attempted to simply couple coal chemical processes with iron and steel metallurgical processes, none of these have broken down the industry barriers between the three major sectors of coal mining, coal chemical industry, and iron and steel metallurgy. They have failed to construct a closed-loop material cycle system that converts harmful hydrocarbon gases generated during coal spontaneous combustion into clean hydrogen sources for blast furnace smelting, and utilizes the inert medium after purification and separation of blast furnace tail gas to precisely control the coal spontaneous combustion process. Existing technologies cannot simultaneously achieve proactive prevention and control of coal spontaneous combustion disasters in coal mines, stable production of low-cost clean hydrogen energy, carbon reduction and efficiency improvement in blast furnace ironmaking, and full-component resource utilization of blast furnace tail gas. They cannot achieve synergistic gains across the three major industrial processes, exhibiting problems such as low system integration, insufficient resource recycling rate, lack of cross-sectoral synergistic effects, and poor overall benefits. Significant technological gaps remain in the co-production of hydrogen and carbon monoxide based on the coal spontaneous combustion-blast furnace tail gas cycle and its comprehensive closed-loop utilization. Summary of the Invention

[0005] This application provides a comprehensive utilization system and method for the co-production of hydrogen and carbon monoxide based on coal spontaneous combustion and blast furnace tail gas recycling. Through intelligent control, coal spontaneous combustion is converted into a stable hydrogen source reactor. The produced hydrogen is used for blast furnace injection to replace fossil fuels, and the purified blast furnace tail gas is used to regulate the coal spontaneous combustion process, thereby forming an industrial ecological chain that achieves efficient material and energy recycling and combines safety and environmental benefits.

[0006] To achieve the above objectives, the technical solution of this invention is as follows: In a first aspect, embodiments of the present invention provide a comprehensive utilization system based on the co-production of hydrogen and carbon monoxide from coal spontaneous combustion and blast furnace tail gas circulation, comprising: a coal spontaneous combustion controlled reaction and hydrocarbon collection unit, a hydrocarbon gas catalytic cracking hydrogen production unit, a hydrogen compression storage and blast furnace hydrogen-rich injection unit, a blast furnace gas purification and component separation and blending unit, and a central intelligent control and optimization platform, which are connected in sequence through pipelines. The injection end of the hydrogen compression storage and blast furnace hydrogen-rich injection unit is connected to the tuyeres of the blast furnace. The gas outlet of the blast furnace is connected to the gas inlet of the blast furnace gas purification and component separation and blending unit through a pipeline. The inert gas outlet of the blast furnace gas purification and component separation and blending unit is connected to the gas injection port of the coal spontaneous combustion controlled reaction and hydrocarbon collection unit through a pipeline, forming a closed material circulation loop of coal spontaneous combustion directional hydrocarbon production, hydrocarbon cracking hydrogen production, hydrogen-rich blast furnace ironmaking, and blast furnace tail gas circulation regulation of coal spontaneous combustion. The central intelligent control and optimization platform is connected to the controlled reaction of coal spontaneous combustion and hydrocarbon collection unit, the catalytic cracking of hydrocarbon gas to produce hydrogen unit, the hydrogen compression and storage and blast furnace hydrogen-rich injection unit, and the blast furnace gas purification and component separation and blending unit. It is used to collect real-time operating data of each unit, dynamically adjust the operating parameters of each unit, coordinate the material and energy balance of the system, and execute global safety interlocks.

[0007] In some possible implementations, the coal spontaneous combustion controlled reaction and hydrocarbon collection unit includes a programmable temperature-controlled coal seam simulation reactor, a multi-channel gas injection and distribution system, and a real-time online monitoring module. The multi-channel gas injection and distribution system is used to inject a mixture of air and inert gas into the coal seam simulation reactor. The real-time online monitoring module includes gas composition monitoring sensors and temperature monitoring sensors to monitor the concentrations of oxygen, carbon monoxide, ethane, and propane, as well as the coal temperature, in the reactor in real time.

[0008] In some possible implementations, the hydrocarbon gas catalytic cracking hydrogen production unit includes a feed gas pretreatment subsystem, a catalytic pyrolysis reactor, and a hydrogen separation and purification device connected in sequence. The feed gas pretreatment subsystem is used to remove dust and desulfurize hydrocarbon-rich gases. The catalytic pyrolysis reactor is loaded with a nickel-based or carbon-based catalyst to catalytically crack ethane and propane into hydrogen and solid carbon. The hydrogen separation and purification device is a pressure swing adsorption (PSA) device used to separate and purify high-purity hydrogen.

[0009] In some possible implementations, the hydrogen compression storage and blast furnace hydrogen-rich injection unit includes a hydrogen compressor, a hydrogen storage device, and a blast furnace injection subsystem connected in sequence; the blast furnace injection subsystem includes a safety injection and mixing component and a dedicated spray gun, which is connected to the tuyeres of the blast furnace and is used to inject pressurized high-purity hydrogen into the blast furnace.

[0010] In some possible implementations, the blast furnace gas purification and component separation and distribution unit includes a dust removal and desulfurization device, a CO2 capture device, and a gas separation device connected in sequence; the gas separation device is a gas distillation device or a membrane separation device, used to separate the treated blast furnace gas into CO-rich gas, inert gas, and other tail gas; the outlet of the CO-rich gas is connected to the blast furnace inlet or the chemical synthesis pipeline, and the outlet of the inert gas is connected to the gas injection port of the controlled coal combustion reaction and hydrocarbon collection unit; the main components of the inert gas are nitrogen and uncaptured carbon dioxide.

[0011] In some possible implementations, the central intelligent control and optimization platform has a built-in trained machine learning model and process control algorithm. The machine learning model is a random forest model. The core control parameters of the central intelligent control and optimization platform include the reaction temperature of the controlled coal combustion reaction and hydrocarbon collection unit, the inert gas injection ratio, the gas flow rate, the reaction temperature of the hydrocarbon gas catalytic cracking hydrogen production unit, and the gas separation ratio of the blast furnace gas purification and component separation and blending unit.

[0012] Secondly, embodiments of the present invention provide a comprehensive utilization method for the co-production of hydrogen and carbon monoxide based on coal spontaneous combustion and blast furnace tail gas recycling, comprising: Coal with a tendency to spontaneously combust is placed in a coal spontaneous combustion reactor, and inert gas from blast furnace tail gas is introduced and injected into the coal seam along with air in a controllable proportion to inhibit the violent oxidation of the coal and create a low-temperature pyrolysis environment for the coal. The composition of the outlet gas and the temperature of the coal seam reaction are monitored online. Based on the coal quality characteristics and real-time monitoring data, the temperature, gas flow rate and the ratio of inert gas to air in the coal seam reaction are dynamically adjusted to ensure that the coal spontaneous combustion reaction operates stably in a high hydrocarbon production mode and continuously produces hydrocarbon-rich gas rich in ethane and propane. After pretreatment, the hydrocarbon-rich gas is fed into a catalytic pyrolysis reactor, where it undergoes a cracking reaction at 550-850℃ with the help of a catalyst to produce hydrogen and solid carbon. After separation and purification, high-purity hydrogen is obtained, and solid carbon by-products are collected at the same time. High-purity hydrogen is pressurized and injected into the blast furnace tuyeres through a special spray gun. The hydrogen burns in the blast furnace to provide heat and acts as a reducing agent to participate in the reduction reaction of iron oxides, replacing part of the coke and pulverized coal, thereby reducing the blast furnace coke ratio and carbon emissions. Blast furnace gas produced by the blast furnace is collected, purified and decarbonized, and then separated into a CO-rich gas stream and an inert gas stream. The CO-rich gas stream is returned to the blast furnace for recycling or supplied as a chemical raw material, while the inert gas stream is transported back to the coal seam reaction stage as a medium to regulate the intensity of the coal auto-combustion reaction, thus completing a closed material cycle. Continuously collect operational data from the entire system, predict the operational trends of key system nodes through models, and automatically fine-tune the operational parameters of each link through feedback control.

[0013] In some possible implementations, the optimization target for the high hydrocarbon production mode is an ethane concentration greater than 200 ppm and a propane concentration greater than 110 ppm, while controlling the oxygen concentration in the coal seam and the core temperature of the coal body below a preset safety threshold; coal quality characteristics include the BET surface area of ​​the coal.

[0014] In some possible implementations, key nodes include hydrocarbon yield, hydrogen yield, blast furnace fuel ratio, and tail gas composition; operating parameters include the composition of the injected gas for coalbed reaction, the temperature of the catalytic pyrolysis reaction, and the gas separation ratio of the blast furnace gas.

[0015] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: This invention constructs a novel closed-loop material cycle paradigm: harmful gases from coal spontaneous combustion → high-value hydrogen energy → green ironmaking → tail gas disaster control. It deeply integrates three independent industrial processes—coal spontaneous combustion prevention, hydrocarbon hydrogen production, and blast furnace ironmaking—into a synergistic ecosystem, achieving efficient co-production and precise utilization of H2 and CO. It not only extracts clean hydrogen energy from coal spontaneous combustion waste resources for application in the steelmaking sector, a field difficult to reduce emissions, to achieve carbon reduction and increased production, but also efficiently recovers and recycles CO from blast furnace gas, improving overall resource utilization.

[0016] Secondly, this invention, through intelligent injection of inert tail gas into the blast furnace and model predictive control, changes the runaway disaster nature of coal spontaneous combustion, transforming it into a controllable production unit that stably supplies hydrocarbon chemical raw materials. This achieves long-term prevention and control of coal spontaneous combustion from the source, improving the safety level of mines. At the same time, it uses hydrocarbons produced as a byproduct of coal spontaneous combustion to produce hydrogen, providing a low-cost and stable hydrogen source for hydrogen-rich injection into the blast furnace. Hydrogen replaces part of the coke and pulverized coal in the ironmaking reaction, effectively reducing the blast furnace coke ratio and process carbon emissions, and achieving carbon reduction and efficiency improvement in steel smelting. Attached Figure Description

[0017] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of a comprehensive utilization system for the co-production of H2 and CO based on coal spontaneous combustion and blast furnace tail gas recycling, provided in an embodiment of the present invention; Figure 2 This is a schematic flowchart of an embodiment of the comprehensive utilization method for H2 and CO based on coal spontaneous combustion and blast furnace tail gas recycling in this invention. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] In the relevant descriptions of this embodiment, the terms "including," "containing," and "possessing" are all open terms and are generally understood to include but not be limited to; the term "at least one" is generally understood to mean one or more, where "multiple" refers to two or more; the term "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items, for example, "at least one of a, b, or c", or "at least one of a, b, and c", which can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple; the symbol "A / B" is used to describe the selection relationship of associated objects, generally indicating an "or" relationship.

[0021] In the following description of the embodiments, the terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms "a" and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0022] Those skilled in the art should understand that, in the following description of the embodiments of this application, the sequence of numbers does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0023] Those skilled in the art will understand that the numerical ranges in the embodiments of this application should be understood to specifically disclose each intermediate value between the upper and lower limits of the range. Any stated value or intermediate value within a stated range, as well as any other stated value or each smaller range between intermediate values ​​within a range, are also included within this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0024] Unless otherwise stated, the technical / scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. While this application describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this application. All references to this specification are incorporated by way of citation to disclose and describe the methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0025] To illustrate the technical solution of the present invention, specific embodiments are described below.

[0026] Figure 1A schematic diagram of a comprehensive utilization system for the co-production of H2 and CO based on coal spontaneous combustion and blast furnace tail gas recycling, provided in an embodiment of the present invention, is shown below. Figure 1 As shown, the above-mentioned integrated utilization system based on coal spontaneous combustion and blast furnace tail gas recycling for H2 and CO production may include: a coal spontaneous combustion controlled reaction and hydrocarbon collection unit, a hydrocarbon gas catalytic cracking hydrogen production unit, a hydrogen compression storage and blast furnace hydrogen-rich injection unit, a blast furnace gas purification and component separation and blending unit, and a central intelligent control and optimization platform, which are connected in sequence through pipelines. The injection end of the hydrogen compression storage and blast furnace hydrogen-rich injection unit is connected to the tuyeres of the blast furnace. The gas outlet of the blast furnace is connected to the gas inlet of the blast furnace gas purification and component separation and blending unit through a pipeline. The inert gas outlet of the blast furnace gas purification and component separation and blending unit is connected to the gas injection port of the coal spontaneous combustion controlled reaction and hydrocarbon collection unit through a pipeline, forming a closed material circulation loop of coal spontaneous combustion directional hydrocarbon production, hydrocarbon cracking hydrogen production, hydrogen-rich blast furnace ironmaking, and blast furnace tail gas circulation regulation of coal spontaneous combustion. The central intelligent control and optimization platform is connected to the controlled reaction of coal spontaneous combustion and hydrocarbon collection unit, the catalytic cracking of hydrocarbon gas to produce hydrogen unit, the hydrogen compression and storage and blast furnace hydrogen-rich injection unit, and the blast furnace gas purification and component separation and blending unit. It is used to collect real-time operating data of each unit, dynamically adjust the operating parameters of each unit, coordinate the material and energy balance of the system, and execute global safety interlocks.

[0027] In some embodiments, the coal spontaneous combustion controlled reaction and hydrocarbon collection unit includes a programmable temperature-controlled coal seam simulation reactor, a multi-channel gas injection and distribution system, and a real-time online monitoring module; the multi-channel gas injection and distribution system is used to inject a mixture of air and inert gas into the coal seam simulation reactor, and the real-time online monitoring module includes a gas composition monitoring sensor and a temperature monitoring sensor for real-time monitoring of oxygen, carbon monoxide, ethane, propane concentrations and coal temperature in the reactor.

[0028] The programmable temperature-controlled coal seam simulation reactor is a tubular reactor with multi-stage independent temperature zone control capabilities. The reactor shell is made of high-temperature resistant material, lined with a heat-insulating refractory layer and an anti-corrosion coating. It has a vertical, closed-loop structure, with a sealed sampling chamber, a layered coal distribution chamber, and a gas distribution chamber arranged sequentially from top to bottom. It can be filled with coal samples of different particle sizes and spontaneous combustion tendencies (including lignite, high-volatile bituminous coal, medium-volatile bituminous coal, and anthracite) according to experimental or engineering needs, accurately simulating the real environment of underground coal seams. Its function is to precisely control the thermodynamic environment of the coal, guiding the spontaneous combustion process dominated by spontaneous oxidation towards a low-temperature pyrolysis path mainly based on free radical fracture and dehydrogenation, thereby enhancing the selective generation of light hydrocarbons such as ethane and propane. This reactor directly corresponds to the directional hydrocarbon production stage of coal spontaneous combustion, and its temperature setpoint forms a closed loop with the control parameters output by the central intelligent control and optimization platform. The reactor's outlet is connected to the pretreatment subsystem of the hydrocarbon gas catalytic cracking hydrogen production unit via an insulated pipe, ensuring that the produced hydrocarbon-rich gas is stably delivered to the downstream unit.

[0029] A multi-channel gas injection and distribution system is installed at the bottom of the coal seam simulation reactor. This system precisely injects a mixture of air and inert gas into the reactor. Specifically, it includes at least two independently controllable gas inlet branches: an air branch and an inert gas branch. The ends of both branches connect to a gas premixing chamber. After thorough mixing in the premixing chamber, the air and inert gas are evenly injected into the coal seam through a porous distribution plate in the reactor's gas distribution chamber. This avoids problems such as localized severe oxidation of the coal or insufficient pyrolysis efficiency caused by uneven local gas concentration.

[0030] The inert gas branch is directly connected to the inert gas outlet of the blast furnace gas purification and component separation and blending unit via a pressurized pipeline. It can directly receive the N2 / CO2 mixture produced by the system's self-circulation. At the same time, it reserves an interface for an external inert gas source for initial inerting during the system startup phase. The system can support two working modes: continuous injection and pulse injection. It can automatically switch according to the instructions of the central intelligent control and optimization platform. In the initial inerting phase, a large flow rate of continuous injection is used to quickly reduce the oxygen content of the coal seam to a safe threshold. In the stable high-hydrocarbon production phase, a precise ratio of continuous and stable injection is used to maintain the low-temperature pyrolysis environment of the coal seam. When the operating conditions fluctuate abnormally, pulse injection is used for rapid adjustment to ensure the stability of system operation.

[0031] The real-time online monitoring module can include at least gas composition monitoring sensors and temperature monitoring sensors. It communicates in real-time with the central intelligent control and optimization platform, providing comprehensive basic data for the system's intelligent regulation. The gas composition monitoring sensors can employ a monitoring architecture combining multi-component infrared gas sensors and electrochemical sensors. Sampling points are located at three key positions: the reactor inlet, the middle of the coal seam, and the outlet. It monitors the concentrations of oxygen, carbon monoxide, ethane, and propane in the reactor and the produced gas in real-time, while also monitoring the concentrations of characteristic gases such as CO2 and CH4. The monitoring range is adapted to the gas change characteristics throughout the entire coal combustion cycle. For example, it can simultaneously quantitatively detect O2 (range 0–21%, accuracy ±0.1%), CO (0–1000ppm, accuracy ±2ppm), C2H6 (0–500ppm, accuracy ±0.5ppm), and C3H8 (0–300ppm, accuracy ±0.3ppm). The monitoring data is uploaded to the central intelligent control and optimization platform in real-time.

[0032] In some embodiments, the workflow of the controlled coal spontaneous combustion reaction and hydrocarbon collection unit is coupled with the overall closed-loop system, as follows: During system startup, an N2 / CO2 inert mixture is received from the blast furnace gas purification and component separation and blending unit via a multi-channel gas injection and distribution system. This mixture is continuously injected into the coal seam simulation reactor at a high flow rate to rapidly reduce the oxygen concentration in the coal seam below a safe threshold, completing initial inerting and inhibiting severe coal oxidation. Subsequently, according to the proportion set by the central intelligent control and optimization platform, a controllable flow rate of air is mixed into the inert gas to gradually adjust the coal seam temperature to the target low-temperature pyrolysis range, guiding the coal from the oxidative spontaneous combustion process to the low-temperature pyrolysis process. During stable operation, the real-time online monitoring module maintains... The system continuously collects coal seam temperature and gas composition data and uploads them to the central platform. The central platform calls the built-in machine learning model to dynamically adjust the inert gas / air injection ratio, gas injection flow rate, and reactor temperature control parameters, so that the system can operate stably in the preset high hydrocarbon production mode, continuously producing hydrocarbon gas streams rich in ethane and propane, which are then transported to the downstream hydrocarbon gas catalytic cracking hydrogen production unit. Under abnormal operating conditions, when the monitoring module detects spontaneous combustion risk signals such as a sudden increase in local coal seam temperature, excessive oxygen concentration, and abnormal surge in CO concentration, it immediately sends an early warning to the central platform. The central platform triggers a global safety interlock, automatically cutting off the air branch and fully opening the inert gas branch, injecting a large flow of inert gas to quickly suppress coal oxidation, thereby preventing coal spontaneous combustion accidents.

[0033] In some embodiments, the hydrocarbon gas catalytic cracking hydrogen production unit includes a feed gas pretreatment subsystem, a catalytic pyrolysis reactor, and a hydrogen separation and purification device connected in sequence. The feed gas pretreatment subsystem is used to remove dust and desulfurize hydrocarbon-rich gases. The catalytic pyrolysis reactor is loaded with a nickel-based catalyst or a carbon-based catalyst to catalytically crack ethane and propane into hydrogen and solid carbon. The hydrogen separation and purification device is a pressure swing adsorption (PSA) device used to separate and purify high-purity hydrogen.

[0034] The feed gas pretreatment subsystem is a pre-purification module located at the inlet of the hydrocarbon gas catalytic cracking hydrogen production unit. It is used to remove dust particles and sulfur-containing impurities (such as H2S, COS, etc.) entrained in the hydrocarbon-rich gas from the controlled coal combustion reaction and hydrocarbon collection unit to prevent catalyst poisoning or bed blockage in the subsequent catalytic pyrolysis reactor. This subsystem can be a multi-stage series structure, for example, including a cyclone dust collector, a ceramic fiber filter, and a zinc oxide desulfurizer bed in sequence. The embodiments of this application do not impose special limitations on the specific structural form, number of stages, and size of each component of this subsystem. Its design parameters can be adapted and set according to the actual dust content, sulfur content, and flow rate of the hydrocarbon-rich gas. The catalytic pyrolysis reactor is one of a fixed-bed reactor, a fluidized-bed reactor, or a moving-bed reactor. Its shell is made of high-temperature resistant alloy steel and lined with a refractory ceramic insulation layer. This reactor provides a controllable high-temperature reaction environment for the catalytic cracking of ethane and propane, and achieves selective breaking of C–H and C–C bonds through a catalyst. It is connected to the feed gas pretreatment subsystem outlet via a high-temperature resistant metal bellows to ensure thermal expansion compatibility. The catalyst loaded inside the reactor is a nickel-based catalyst, such as Ni / Al₂O₃, Ni / SiO₂, or Ni / TiO₂, wherein the mass fraction of the nickel active component is... The catalyst composition is 5%–20%, with a support surface area of ​​150–300 m² / g; or it is a carbon-based catalyst, such as a composite material of activated carbon supported on transition metals (Fe, Co), or carbon nanotubes treated with high-temperature graphitization; the catalyst bed adopts a multi-stage temperature zone arrangement, with the inlet temperature controlled at 550–650℃ to promote the initial activation of C2H6, the middle stage temperature raised to 700–800℃ to accelerate the deep cracking of C3H8, and the outlet temperature maintained at 600–680℃ to inhibit excessive carbon deposition; the reaction pressure is atmospheric pressure to 0.5 MPa, and the space velocity (GHSV) is 500–2000 h⁻¹. -1 The embodiments of this application do not impose special limitations on the specific type, size, operating pressure and space velocity of the reactor. Its selection and operating parameters can be dynamically adjusted according to the concentration ratio of ethane to propane, the target hydrogen yield and the requirements of solid carbon morphology. The hydrogen separation and purification unit is a pressure swing adsorption (PSA) unit, a periodic operation unit that achieves selective separation based on the differences in adsorption affinity of different gases on the adsorbent surface. It is used to efficiently extract high-purity hydrogen from the outlet gas of a catalytic pyrolysis reactor, producing a desorbed gas stream rich in light hydrocarbons and CO as a byproduct. The PSA unit can include 4-12 adsorption towers, with adsorbents such as zeolite molecular sieves (e.g., 13X), activated carbon, or metal-organic framework materials. 13X molecular sieves have strong adsorption capacity for CO, CH4, and C2+ hydrocarbons, but weak adsorption for H2. Each adsorption tower is filled with a multi-layered gradient packing structure, with a bottom layer of large-pore support, a middle layer of... The main adsorption layer is topped by a protective layer. The PSA process cycle includes six steps: adsorption, pressure equalization, forward release, reverse release, rinsing, and pressure equalization boost. A complete cycle takes 30–120 seconds. By adjusting the adsorption time, the number of pressure equalization cycles, and the rinsing gas ratio, the purity of the product hydrogen can be stably maintained at over 99.9%, with a recovery rate of no less than 85%. The desorbed gas can be returned to the catalytic pyrolysis reactor as fuel gas to supplement heat, or sent to the tail gas combustion system for treatment. This application does not impose special limitations on the number of PSA towers, the type of adsorbent, the cycle sequence, or the destination of the desorbed gas. Its configuration can be optimized according to hydrogen purity requirements, system energy efficiency targets, and by-product gas utilization paths. Specifically, the process of the hydrocarbon gas catalytic cracking hydrogen production unit and the entire system operating in a closed loop is as follows: The hydrocarbon-rich feed gas produced by the controlled reaction of coal auto-combustion and the hydrocarbon collection unit first enters the feed gas pretreatment subsystem, where it undergoes a full-process purification process including dust removal, desulfurization, dehydration, and pressure stabilization to obtain clean hydrocarbon-rich gas that meets the requirements for catalyst feed. The clean feed gas is then fed into the catalytic pyrolysis reactor at a set flow rate and space velocity. Under the action of the catalyst at a reaction temperature of 550-850℃, ethane and propane undergo directional catalytic cracking reactions to generate a hydrogen-rich mixed gas and solid carbon byproducts. The hydrogen-rich mixed gas produced by cracking is sent to a hydrogen separation and purification unit. After purification by PSA pressure swing adsorption, high-purity hydrogen product is obtained and transported to the downstream hydrogen compression storage and blast furnace hydrogen-rich injection unit for use in blast furnace hydrogen enrichment. Hydrogen injection reduces carbon emissions; desorbed gas and unreacted hydrocarbon gases generated during the separation process are returned to the inlet of the catalytic pyrolysis reactor via a reflux pipeline for secondary cracking, achieving full utilization of the raw materials; solid carbon generated by cracking is collected by a capture system and stored as a byproduct; throughout the entire operation, the central intelligent control and optimization platform collects real-time operating data such as temperature, pressure, gas composition, flow rate, and impurity content of each device in the unit, dynamically adjusting the operating conditions of the pretreatment subsystem, the reaction temperature and feed flow rate of the catalytic pyrolysis reactor, and the adsorption cycle parameters of the hydrogen separation and purification device to ensure that the hydrocarbon cracking efficiency, hydrogen yield, and product purity are always within the optimal range, while dynamically matching the operating conditions with the upstream coal self-ignition unit and the downstream blast furnace injection unit to achieve material and energy balance of the entire system.

[0035] In this embodiment of the invention, by setting up a feed gas pretreatment subsystem, catalyst poisoning and blockage are effectively avoided, and the operating cycle of the catalytic pyrolysis reactor is extended. By limiting the loading of nickel-based or carbon-based catalysts in the catalytic pyrolysis reactor and controlling the reaction temperature within the range of 550–850°C, ethane and propane can achieve efficient bond breaking with low energy consumption, thereby improving the hydrogen production efficiency per unit volume of feed gas. By using a PSA as a hydrogen separation and purification device, there is no need for cryogenic or membrane material dependence, and it has the characteristics of mature technology, flexible start-up and shutdown, and strong adaptability to load fluctuations, thus supporting the robust operation of the entire system under conditions such as coal quality fluctuations and gas volume changes.

[0036] In some embodiments, the hydrogen compression storage and blast furnace hydrogen-rich injection unit includes a hydrogen compressor, a hydrogen storage device, and a blast furnace injection subsystem connected in sequence; the blast furnace injection subsystem includes a safety injection and mixing component and a dedicated spray gun, which is connected to the tuyeres of the blast furnace and is used to inject pressurized high-purity hydrogen into the blast furnace.

[0037] The hydrogen compressor can be a diaphragm compressor or an ionic liquid compressor, used to pressurize the atmospheric or low-pressure hydrogen output from the hydrocarbon gas catalytic cracking hydrogen production unit to a pressure range of 1.5–5.0 MPa. This pressure level meets the requirements of long-distance pipeline transportation and hydrogen storage device filling, and is also suitable for the dynamic response requirements under blast furnace tuyeres injection conditions. The inlet end of the hydrogen compressor is connected to the outlet of the hydrogen separation and purification device of the hydrocarbon gas catalytic cracking hydrogen production unit through a hydrogen embrittlement-resistant stainless steel pipe, and the outlet end is connected to the inlet of the hydrogen storage device. Its compression process adopts a multi-stage cooling and intermediate buffer design to control the exhaust temperature below 80°C, avoiding the risk of hydrogen embrittlement of materials due to high temperature. The operating parameters of the hydrogen compressor, including compression ratio, exhaust pressure and cooling water flow rate, are all controlled in real time by a central intelligent control and optimization platform to match the downstream hydrogen storage and injection rhythm.

[0038] The hydrogen storage device is a fixed high-pressure gaseous storage tank or a buffer gas storage tank with pressure regulation function. Its volume can be set according to the amount of hydrogen required for a single blast furnace injection cycle and the fluctuation of upstream hydrogen production. The inner wall of the storage tank is treated with nickel plating or ceramic coating to enhance its resistance to hydrogen permeation and hydrogen embrittlement. The gas inlet of the storage tank is connected to the outlet of the hydrogen compressor, and the gas outlet is connected to the inlet of the safety injection and mixing components of the blast furnace injection subsystem. A pressure transmitter and temperature sensor are installed at the top of the storage tank, and an automatic drain valve is installed at the bottom to periodically drain the trace amounts of moisture condensed during the compression process. The hydrogen storage device plays a role in supply and demand balance and pressure buffering in the system, allowing the catalytic cracking hydrogen production unit of hydrocarbon gas to maintain continuous blast furnace injection during periodic maintenance or load adjustment. The blast furnace injection subsystem includes a safety injection and mixing component and a dedicated injection gun. The safety injection and mixing component may include an emergency shut-off valve, a flame arrester, a flow regulating valve, a static mixer, and a hot blast mixing interface, arranged in series. The entire safety injection and mixing component is installed outside the blast furnace hot blast casing, with its inlet receiving high-pressure hydrogen from the hydrogen storage unit and its outlet connected to the dedicated injection gun. The emergency shut-off valve responds to safety interlock signals from the central intelligent control and optimization platform, completing a full shut-off action within 0.5 seconds upon detecting hydrogen leakage, abnormal pressure, or sudden changes in blast furnace operating conditions. The flame arrester adopts a sintered metal mesh structure with a pore size... With a thickness of ≤0.02mm, it can effectively prevent the flame from spreading in the hydrogen pipeline; the static mixer is equipped with a spiral guide vane, so that the incoming hydrogen and the 1200℃ hot air from the blast furnace hot blast main pipe can complete the initial turbulent mixing in front of the spray gun, improving the uniformity of contact between the two; the hot air mixing interface is located downstream of the static mixer to ensure that the hydrogen has formed a stable premixed airflow with the high temperature hot air before entering the special spray gun; the special spray gun undertakes the functions of precise hydrogen injection and efficient activation at the end of the system, so that the hydrogen can be rapidly dissociated in the high temperature reducing atmosphere and participate in the stepwise reduction reaction chain of Fe2O3→Fe3O4→FeO→Fe.

[0039] Specifically, in this embodiment of the invention, the working process of the hydrogen compression storage and blast furnace hydrogen-rich injection unit is as follows: High-purity hydrogen from the hydrocarbon gas catalytic cracking hydrogen production unit first enters the hydrogen compressor. Under the target pressure command calculated by the central intelligent control and optimization platform based on the current fuel ratio of the blast furnace and the theoretical combustion temperature of the tuyeres, it is compressed to the set pressure. After cooling and dehumidification, the compressed hydrogen is sent to the hydrogen storage device for temporary storage. When the blast furnace enters the injection cycle, the outlet pressure of the hydrogen storage device triggers the start of the safety injection and mixing components, the emergency shut-off valve is opened, and the hydrogen flows through the flame arrester and flow regulating valve, and then completes primary mixing with 1200°C hot air in the static mixer. The premixed gas flow then enters the special spray gun, and under the constraint of the high-temperature alloy nozzle and the guidance of the micro-pore array, it is injected into the blast furnace tuyeres swirling zone in the form of multiple fine jets, achieving uniform spatial distribution and synchronous ignition in time, ensuring that the hydrogen plays a dual role as a heat source and reducing agent in the melting zone.

[0040] In some embodiments, the blast furnace gas purification and component separation and blending unit includes a dust removal and desulfurization device, a CO2 capture device, and a gas separation device connected in sequence; the gas separation device is a gas distillation device or a membrane separation device, used to separate the treated blast furnace gas into CO-rich gas, inert gas, and other tail gas; the outlet of the CO-rich gas is connected to the blast furnace inlet or the chemical synthesis pipeline, and the outlet of the inert gas is connected to the gas injection port of the controlled coal combustion reaction and hydrocarbon collection unit; the main components of the inert gas are nitrogen and uncaptured carbon dioxide.

[0041] The dust removal and desulfurization device can be a combined purification unit consisting of a cyclone dust collector and a wet desulfurization tower connected in series, or a modular structure consisting of an electrostatic precipitator and a dry desulfurization reactor connected in parallel and coupled. The dust removal and desulfurization device is used to remove dust particles with a diameter greater than 1μm and acidic gases such as hydrogen sulfide and sulfur dioxide from blast furnace gas, prevent the packing of the subsequent CO2 capture device from becoming clogged and the catalyst from becoming poisoned, and ensure the cleanliness of the gas inlet of the gas separation device. Its inlet is connected to the main pipeline of blast furnace gas, and its outlet is connected to the inlet of the CO2 capture device through a pipeline. A buffer pressure stabilizing tank can be set between the two to balance instantaneous airflow fluctuations. The CO2 capture device can be an amine absorption tower, a cryogenic separation unit, or a solid adsorption bed. The CO2 capture device is used to selectively remove 50%–95% of the CO2 components from blast furnace gas, reduce the load on subsequent gas separation, and achieve preliminary enrichment of carbon resources. Its inlet is connected to the outlet of the dust removal and desulfurization unit, and the CO2 volume concentration in the outlet gas can be controlled at 1%–15%. The specific value can be dynamically set according to the CO2 ratio requirement of the inert gas in the coal self-combustion process. The regeneration gas flow of this device can be directed to the combustion unit or compressed and liquefied for storage, and does not enter the main circulation loop of this system. The gas separation device can be a multi-stage distillation column system, for example, with 20-60 trays, an operating pressure of 0.3-0.8 MPa, a CO-rich distillate at the top, and the remaining liquid at the bottom as tail gas, with an inert gas stream drawn off from the side. Alternatively, it can be a hollow fiber membrane module, using polyimide or palladium-silver alloy composite membranes, with a membrane area of ​​50-500 m², and an operating temperature of 303-353 K. Selective permeation separation of CO / N₂ / CO₂ is achieved by adjusting the pressure difference across the membrane and the gas flow rate. The gas separation device is used to separate the purified coal gas after CO₂ capture into components according to their boiling points. Precise diversion is achieved based on differences in point or permeation rate, resulting in three independent gas streams: CO-rich gas (CO volume concentration ≥ 50%, O2 content < 1%), inert gas (N2 volume percentage ≥ 65%, CO2 volume percentage 5%–30%, O2 content < 5%), and the remaining tail gas (mainly containing H2, CH4, trace organic matter, and residual impurities). The CO-rich gas outlet is connected to the combustion air pipeline of the blast furnace hot blast stove or the inlet pipeline of the methanol synthesis reactor, while the inert gas outlet is connected to the gas injection port of the controlled coal combustion reaction and hydrocarbon collection unit through a pressure-resistant gas pipeline, forming a closed loop. Specifically, the blast furnace gas first enters the dust removal and desulfurization unit, where, under the synergistic effect of gravity settling and liquid film absorption, the dust removal rate is >99%, and the H2S and SO2 removal rates are >95%. It then enters the CO2 capture unit, where CO2 selective enrichment is achieved under atmospheric to medium pressure conditions. The capture efficiency can be dynamically adjusted within the range of 40%–90% according to instructions issued by the central intelligent control and optimization platform. Finally, it enters the gas separation unit, where, according to a preset separation ratio, the purified gas flow is precisely divided into three streams: CO-rich gas, after pressure regulation, is directly supplied to the blast furnace hot blast stove for combustion and temperature increase, or transported to downstream chemical units as a carbon source; inert gas, after cooling and drying, is pressurized to 0.2–0.4 MPa and transported to the coal seam simulation reactor to dilute the oxygen concentration and inhibit free radical chain oxidation reactions, thereby guiding coal auto-combustion towards a controllable pyrolysis path; the remaining tail gas is introduced into the flare system for safe combustion or sent to a gas-fired boiler for waste heat recovery. The preset separation ratio can be calculated in real time by the central platform based on the coal surface area, historical hydrocarbon yield, and current inert gas inventory.

[0042] In this embodiment of the invention, by setting up a dust removal and desulfurization device, a CO2 capture device, and a gas separation device connected in sequence, blast furnace gas can be purified in a graded and gradient manner, avoiding the overload failure of a single purification unit. The gas separation device can be a gas distillation device or a membrane separation device, which can be adapted to different scales and investment constraints, ensuring separation flexibility and engineering robustness. The inert gas stream is directionally transported back to the controlled reaction of coal spontaneous combustion and hydrocarbon collection unit, constructing a negative feedback closed loop with blast furnace tail gas as the control medium, so that the coal spontaneous combustion process is transformed from a disaster state to a production state. The CO-rich gas can be returned to the blast furnace or supplied to chemical synthesis, improving the local consumption rate of CO resources and the overall energy efficiency of the system.

[0043] In some embodiments, the central intelligent control and optimization platform has a built-in trained machine learning model and process control algorithm, and the machine learning model is a random forest model; the core control parameters of the central intelligent control and optimization platform include the reaction temperature of the controlled reaction of coal spontaneous combustion and hydrocarbon collection unit, the inert gas injection ratio, the gas flow rate, the reaction temperature of the hydrocarbon gas catalytic cracking hydrogen production unit, and the gas separation ratio of the blast furnace gas purification and component separation and blending unit.

[0044] The central intelligent control and optimization platform can be a hardware and software collaborative system integrated into an industrial control server. Its hardware includes data acquisition cards, PLC controllers, edge computing modules, and human-machine interface terminals, while its software includes data communication middleware, a model inference engine, process control algorithm modules, and a visual monitoring interface. This platform connects to the sensors and actuators of each functional unit via industrial Ethernet or fieldbus to collect real-time operating data such as temperature, pressure, gas concentration, flow rate, and valve opening. It then sends control commands to the regulating valves, heating devices, fans, compressors, and separation equipment actuators of each unit. The trained machine learning model can be a data-driven prediction model trained using historical operating data and simulation data. This model is used to establish a nonlinear mapping relationship between multiple input variables and key performance indicators, thereby enabling early prediction of system operating trends. A random forest model can be a specific implementation of this machine learning model. It consists of multiple integrated decision trees and has advantages such as resistance to overfitting, feature importance assessment, and robustness to missing data. It is suitable for the complex coal spontaneous combustion reaction dynamics, strong multi-source disturbances, and large fluctuations in operating conditions characteristic of this system. The process control algorithm can be a model predictive control (MPC) or a fuzzy PID composite control algorithm. It receives the trend prediction results output by the machine learning model and the set target value, and combines the dynamic response characteristics of each unit to generate the optimal control action sequence for the actuators, so as to achieve smooth, accurate and rapid adjustment of parameters. The reaction temperature of the coal spontaneous combustion controlled reaction and hydrocarbon collection unit can refer to the average temperature or core area temperature reflected by the temperature measurement point inside the coal seam simulated reactor. Its regulatory role is to affect the selection of coal pyrolysis reaction path and hydrocarbon generation rate. This temperature, together with the inert gas injection ratio and gas flow rate, constitutes the triple synergistic regulation of the coal spontaneous combustion controlled reaction and hydrocarbon collection unit. The three dimensions, when combined, can suppress severe oxidation and promote the selective formation of C2H6 and C3H8; the inert gas injection ratio refers to the percentage of inert gas injected into the coal seam to the total injected gas volume. Its regulatory role is to dilute the oxygen concentration and adjust the heat capacity of the reaction system. This ratio is linked with the reaction temperature and gas flow rate, jointly determining the local oxygen potential and heat transfer efficiency of the coal seam, thereby affecting the stability of hydrocarbon yield; the gas flow rate refers to the total volumetric flow rate of the mixed gas entering the coal seam simulated reactor. Its regulatory role is to control the mass transfer rate of reactants and the product carry-out efficiency. This flow rate, in conjunction with the reaction temperature and the inert gas injection ratio, can avoid the aggravation of side reactions caused by local heat accumulation or product retention. The reaction temperature of the hydrocarbon gas catalytic cracking hydrogen production unit can refer to the axial average temperature of the catalyst bed in the catalytic pyrolysis reactor. Its regulatory role is to affect the cracking conversion rate of ethane and propane and the selectivity of hydrogen. This temperature is coupled with the reaction temperature of the controlled coal combustion reaction and the hydrocarbon collection unit, because the gas composition of the former directly affects the feed load and heat balance of the latter. The gas separation ratio of the blast furnace gas purification and component separation and blending unit can refer to the proportion of CO-rich gas flow in the gas distillation unit or membrane separation unit to the total volume of the processed blast furnace gas. Its regulatory role is to balance the demand for CO-rich gas external supply / return to the furnace and the supply of inert gas circulation. This ratio forms a closed loop feedback with the inert gas injection ratio of the controlled coal combustion reaction and the hydrocarbon collection unit to ensure that the total amount of inert medium dynamically matches the demand for coal combustion regulation. Specifically, the central intelligent control and optimization platform collects real-time data from temperature and gas composition sensors in the controlled coal combustion reaction and hydrocarbon collection unit, temperature and pressure sensors in the hydrocarbon gas catalytic cracking hydrogen production unit, and flow meter and component analyzer data in the blast furnace gas purification and component separation and blending unit. This multi-source heterogeneous data is then input into a random forest model for inference, predicting the trends in hydrocarbon yield, hydrogen yield, and blast furnace fuel ratio over the next 10–30 minutes. When the predicted values ​​deviate from the set target range, the process control algorithm automatically calculates and issues new reaction temperature setpoints, inert gas injection ratio setpoints, gas flow rate setpoints, catalytic cracking reaction temperature setpoints, and gas separation ratio setpoints based on the prediction deviation, the hysteresis characteristics of each parameter adjustment, and safety constraints. This drives the corresponding actuators to operate, thereby achieving feedforward-feedback coordinated control of the entire system's multi-variable, strongly coupled processes.

[0045] In this invention, a novel closed-loop material cycle paradigm is constructed, encompassing coal spontaneous combustion hazardous gases → high-value hydrogen energy → green ironmaking → tail gas disaster control. This deeply integrates three independent industrial processes—coal spontaneous combustion prevention, hydrocarbon hydrogen production, and blast furnace ironmaking—into a synergistic ecosystem, achieving efficient co-production and precise utilization of H2 and CO. It not only extracts clean hydrogen energy from coal spontaneous combustion waste resources for application in the steel smelting sector, a field difficult to reduce emissions, to achieve carbon reduction and increased production, but also efficiently recovers and recycles CO from blast furnace gas, improving overall resource utilization.

[0046] Secondly, this invention, through intelligent injection of inert tail gas into the blast furnace and model predictive control, changes the runaway disaster nature of coal spontaneous combustion, transforming it into a controllable production unit that stably supplies hydrocarbon chemical raw materials. This achieves long-term prevention and control of coal spontaneous combustion from the source, improving the safety level of mines. At the same time, it uses hydrocarbons produced as a byproduct of coal spontaneous combustion to produce hydrogen, providing a low-cost and stable hydrogen source for hydrogen-rich injection into the blast furnace. Hydrogen replaces part of the coke and pulverized coal in the ironmaking reaction, effectively reducing the blast furnace coke ratio and process carbon emissions, and achieving carbon reduction and efficiency improvement in steel smelting.

[0047] Based on the same inventive concept, this application also provides a comprehensive utilization method for H2 and CO based on coal spontaneous combustion and blast furnace tail gas recycling. Figure 2 This is a schematic flowchart of an embodiment of the comprehensive utilization method for H2 and CO based on the co-production of coal spontaneous combustion and blast furnace tail gas recycling in this invention. See also: Figure 2 As shown, the method may include: S201 involves placing coal with a tendency to spontaneously combust in a coal spontaneous combustion reactor, introducing inert gas from blast furnace tail gas in a controlled ratio, and injecting it into the coal seam to inhibit severe oxidation of the coal and create a low-temperature pyrolysis environment for the coal. Understandably, the coal spontaneous combustion reactor is a programmable temperature-controlled coal seam simulation reactor. Its structure is adapted to the pore distribution and heat and mass transfer characteristics of real coal seams, used to simulate and control the spontaneous combustion evolution process of coal under controlled conditions. The temperature control range of this reactor is 300K–500K to ensure that the coal does not enter the violent oxidation and exothermic stage, but remains stably in the hydrocarbon production range dominated by pyrolysis. The inert gas from the blast furnace tail gas is the gas stream remaining after dust removal, desulfurization, and CO2 capture, output from the blast furnace gas purification and component separation and blending unit. Its main components are nitrogen and incompletely captured carbon dioxide, with an oxygen content lower than 1%. The inert gas, containing 5% oxygen and free of combustible components, acts as a reaction atmosphere control medium. By diluting the oxygen concentration and reducing the local reaction rate, it physically blocks the chain reaction of coal oxidation. The controllable proportion of air is an oxygen-containing gas that is mixed with the inert gas at a preset volume ratio and then introduced into the reactor. The injection ratio is dynamically set according to the coal quality characteristics, initial coal temperature, and target hydrocarbon production window. The typical ratio range is 5%–15% of the total volume of the mixed gas. This ratio control directly determines the oxygen partial pressure level in the reactor, thereby affecting the competitive balance between coal pyrolysis and partial oxidation. It is a key operating parameter for achieving the dual goals of inhibiting severe oxidation and maintaining pyrolysis activity. In some embodiments, this application may dynamically adjust the intake volume of the two gases through a proportional control valve group based on the real-time flow feedback signals of the inert gas and air; this application may also use a PID closed-loop control algorithm to reversely correct the air injection ratio based on the online monitoring value of the oxygen concentration at the reactor outlet; further, this application may pre-adjust the mixture composition 0.5–2 hours in advance based on the predictive control instructions output by the machine learning model built into the central intelligent control and optimization platform; this application obtains a stable and controllable low-temperature pyrolysis environment based on any of the above methods, so that the coal spontaneous combustion process is transformed from catastrophic uncontrollable oxidation to resource-based controllable hydrocarbon production.

[0048] S202 monitors the composition of the outlet gas and the temperature of the coal seam reaction online. Based on the coal quality characteristics and real-time monitoring data, it dynamically adjusts the temperature, gas flow rate and the ratio of inert gas to air in the coal seam reaction, so that the coal spontaneous combustion reaction can operate stably in a high hydrocarbon production mode and continuously produce hydrocarbon-rich gas rich in ethane and propane. Understandably, the outlet gas composition consists of the concentrations of oxygen, carbon monoxide, ethane, and propane. Monitoring is conducted using real-time online gas composition sensors with a response time of less than 30 seconds and detection limits of 1 ppm (O2), 0.5 ppm (CO), 0.1 ppm (C2H6), and 0.05 ppm (C3H8), respectively. The coal temperature refers to the temperature of the core region within the coal seam, collected at multiple points using thermocouple arrays buried at different depths within the coal seam, with a sampling frequency of no less than 1 Hz. Coal quality characteristics are inherent parameters reflecting the coal's microstructure and reactivity, including but not limited to the coal's BET surface area, volatile matter content, and vitrinite reflectance. These parameters serve as model input features, used to calibrate the prediction benchmark of the machine learning model in the central intelligent control and optimization platform. The high-hydrocarbon production mode is an operational state with ethane and propane yields as the optimization objective. It represents maximizing the generation rate and cumulative concentration of C2H6 and C3H8 while ensuring that the core coal temperature and oxygen concentration are within safe thresholds (e.g., temperature ≤ 420 K, O2 ≤ 200 ppm).

[0049] In some embodiments, this application may maintain the current temperature and ratio unchanged based on the determination that the C2H6 concentration in the outlet gas is higher than 200 ppm and the C3H8 concentration is higher than 110 ppm for 3 consecutive minutes; this application may also automatically lower the reaction temperature and increase the proportion of inert gas when the CO concentration rise rate is detected to exceed the threshold, so as to suppress deep oxidation side reactions.

[0050] S203 involves pre-treating hydrocarbon-rich gas and then passing it into a catalytic pyrolysis reactor. Under the action of a catalyst at 550-850℃, a cracking reaction occurs to generate hydrogen and solid carbon. After separation and purification, high-purity hydrogen is obtained, and solid carbon by-products are collected at the same time. The hydrocarbon-rich gas is the gas stream from the controlled coal combustion reaction and hydrocarbon collection unit outlet. This gas needs to be pretreated before entering the catalytic pyrolysis reactor to remove dust particles and sulfide impurities and prevent catalyst poisoning. The catalytic pyrolysis reactor is a tubular or fixed-bed reactor, loaded with nickel-based or carbon-based catalysts. The nickel-based catalyst is a porous solid material with NiO as the active component and Al2O3 or SiO2 as the support, which forms highly dispersed Ni nanoparticles after reduction and activation. The carbon-based catalyst is a graphene derivative or activated carbon-supported metal additive material with high specific surface area and abundant edge defect sites. Both types of catalysts can efficiently drive the C-C bond breaking and C-H bond recombination reactions of ethane and propane in the temperature range of 550–850℃. The cracking reaction is a process in which hydrocarbon molecules are adsorbed, activated and undergo bond breaking and rearrangement on the catalyst surface under anaerobic or micro-oxygen conditions. The main reaction pathways include ethane dehydrogenation condensation to produce carbon and hydrogen, propane cracking to methane and ethylene and further conversion, etc., which are characterized by net hydrogen production and carbon deposition.

[0051] S204 involves pressurizing high-purity hydrogen and injecting it into the blast furnace tuyeres through a special spray gun. The hydrogen burns inside the blast furnace to provide heat and acts as a reducing agent in the reduction reaction of iron oxides, replacing some of the coke and pulverized coal, thereby reducing the blast furnace coke ratio and carbon emissions. Specifically, high-purity hydrogen is the product purified by a hydrogen separation and purification device, with a purity greater than 99.9%. Impurities mainly include trace amounts of CH4, CO, and N2, with a total content of less than 100 ppm. The special spray gun is a high-temperature resistant and corrosion-resistant dual-channel or multi-channel nozzle. The outer channel delivers hydrogen, while the inner channel can simultaneously inject a small amount of nitrogen or steam to adjust the flame shape and penetration depth. The nozzle design is adapted to the diameter of the blast furnace tuyeres and the airflow velocity. The combustion of hydrogen in the blast furnace provides heat by reacting with residual oxygen or iron oxides in the blast furnace exothermically, releasing heat and replenishing the heat balance of the hearth. As a reducing agent, hydrogen participates in the reduction reaction of iron oxides by reacting with Fe2O3, Fe3O4, and FeO in the upper part of the furnace body in a stepwise gas-solid reduction reaction. Its kinetic rate is significantly higher than that of CO reduction, especially in the low-temperature zone. For example, this application may dynamically adjust the proportion of hydrogen injection to the total fuel energy at the tuyeres based on the combined feedback of the H2 / CO ratio in the blast furnace top gas and the hearth temperature; or it may pre-adjust the injection intensity using a feedforward-feedback composite control strategy based on the historical trends of the silicon content in molten iron and the slag-iron temperature; furthermore, this application may also combine the change rate of CO2 concentration in the blast furnace gas to assess the contribution of hydrogen reduction in real time and correct the injection parameters in reverse.

[0052] S205 collects blast furnace gas produced by the blast furnace. After purification and decarbonization, the blast furnace gas is separated into a CO-rich gas stream and an inert gas stream. The CO-rich gas stream is returned to the blast furnace for recycling or supplied as a chemical raw material. The inert gas stream is transported back to the coal seam reaction stage as a medium to regulate the intensity of coal auto-ignition reaction, thus completing a closed material cycle. Understandably, blast furnace gas is a by-product gas produced during the blast furnace ironmaking process. Purification and decarbonization treatment includes, in sequence: mechanical dust removal, wet desulfurization, and CO2 capture. After treatment, the sulfur content in the gas is below 1 ppm, and the CO2 content is reduced to 5–10% (e.g., 7.3%). The separation of CO-rich gas stream and inert gas stream is achieved through a gas distillation unit or a membrane separation unit. The gas distillation unit is a tower system that performs low-temperature fractionation based on the boiling point differences of each component. The membrane separation unit is a modular system that uses polyimide or palladium alloy composite membranes to selectively enrich CO and N2 / CO2 by utilizing the difference in permeation rates within the membrane. The CO-rich gas stream has a CO volume concentration greater than 50% (e.g., 65%) and can be directly returned to the blast furnace tuyeres as auxiliary fuel, or compressed and stored for use in chemical processes such as methanol synthesis and Fischer-Tropsch synthesis. The inert gas stream mainly consists of N2 and residual CO2, with an oxygen content below 5%. It is reinjected into the coal auto-ignition reactor as a closed-loop control medium, forming the core carrier gas of the material circulation loop.

[0053] S206 continuously collects operational data from the entire system, predicts the operational trends of key system nodes through models, and automatically fine-tunes the operational parameters of each component through feedback control.

[0054] The system's operational data includes, but is not limited to: coal seam reactor temperature field distribution, outlet gas component concentration sequence, catalytic pyrolysis reactor inlet and outlet temperatures and pressure difference, hydrogen purity and flow rate, blast furnace tuyere hydrogen injection pressure and instantaneous flow rate, blast furnace gas composition and calorific value, and outlet flow rate and composition of each gas separation unit. All data are uploaded to the central intelligent control and optimization platform at 1–10 second intervals. The model predicts the operational trends of key nodes in the system using a random forest model built into the central intelligent control and optimization platform. This model uses historical operational data as its training set, and its input features include coal quality parameters, real-time operating variables of each unit, and time series variables with lag orders of 1–5. The output prediction targets are the changing trends of four key nodes—hydrogen yield, hydrogen yield, blast furnace fuel ratio, and tail gas composition—within the next 1–60 minutes. The feedback control automatically fine-tunes the operating parameters of each link by generating control commands and issuing them to the execution units based on the comparison results between the prediction deviation and the set threshold. For example, when it is predicted that the hydrocarbon yield will decrease by more than 10% after 15 minutes, the platform automatically sends a combined instruction of increasing the temperature by +0.3 K / min and increasing the inert gas ratio by +0.8% to the coal spontaneous combustion controlled reaction and hydrocarbon collection unit; when it is predicted that the blast furnace fuel ratio will increase beyond the allowable bandwidth, an instruction of increasing the injection volume by 5% is sent to the hydrogen compression storage and blast furnace hydrogen-rich injection unit.

[0055] In some embodiments, the optimization target of the high hydrocarbon production mode is that the ethane concentration is greater than 200 ppm and the propane concentration is greater than 110 ppm, while the oxygen concentration in the coal seam and the core temperature of the coal body are controlled below a preset safety threshold; the coal quality characteristics include the BET surface area of ​​the coal.

[0056] In some embodiments, key nodes include hydrocarbon yield, hydrogen yield, blast furnace fuel ratio, and tail gas composition; operating parameters include the composition of the injected gas for coalbed reaction, the temperature of the catalytic pyrolysis reaction, and the gas separation ratio of the blast furnace gas.

[0057] The method of the present invention will be described below with reference to a specific embodiment: For example, this invention can be deployed in an integrated demonstration park, using local high-volatile bituminous coal as raw material. In a controlled coal combustion reaction and hydrocarbon collection unit, an inert mixture (N2-70%, CO2-30%) from blast furnace tail gas is injected to control the coal bed temperature at 380K. Under the regulation of a central intelligent control and optimization platform, hydrocarbon gas is continuously produced, with an average C2H6 concentration of 205ppm and an average C3H8 concentration of 108ppm. This hydrocarbon-rich gas, after pretreatment, is fed into a catalytic pyrolysis reactor (reaction temperature 720°C, nickel-based catalyst), achieving a hydrogen yield of 7.18 mol / m³. After PSA separation, the hydrogen purity reached 99.95%. The obtained hydrogen was injected into a 2000m³ blast furnace at a ratio of 20% of the total fuel calorific value at the blast furnace tuyeres. Monitoring showed that the coke ratio decreased by 8.5%, the output increased by 3%, the H2 content in the blast furnace gas increased, and the CO2 emission intensity decreased by about 10%. After purification and separation, part of the CO-rich gas (CO concentration 65%) was returned to the furnace, and the inert gas was pressurized and sent back to the coal bed. After one week of system operation, the external inert gas replenishment demand decreased by 90%. The central platform successfully predicted and automatically adjusted the hydrocarbon yield decline caused by coal quality fluctuations twice, and restored it to the optimal state within 2 hours.

[0058] In this invention, by transforming the coal spontaneous combustion process from passive prevention to active control, and by creating a controllable low-temperature pyrolysis environment using inert gas from blast furnace tail gas, a fundamental transformation from a disaster source to a resource-based reactor is achieved. Online monitoring and model-driven dynamic parameter optimization ensure the long-term stable operation of the high-hydrogen-yield mode. The coupling of catalytic cracking of hydrocarbon-rich gas for hydrogen production and blast furnace hydrogen-rich injection achieves the unification of on-site hydrogen production, on-site consumption, and deep carbon reduction. Through the purification and separation of blast furnace gas and the closed-loop reuse of inert components, a complete material cycle covering coal → hydrocarbon → hydrogen → iron → gas → coal is constructed. Finally, by leveraging a central intelligent control and optimization platform for the fusion analysis and closed-loop execution of multi-source heterogeneous data, an autonomous operating mechanism of perception-analysis-decision-execution-re-perception is formed. This solves systemic technical challenges such as difficult cross-industry process coupling, multi-objective synergy optimization, and poor controllability of disaster processes, thereby achieving deep integration and synergistic gains in the three major fields of energy, metallurgy, and mine safety.

[0059] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, please refer to each other. Each embodiment focuses on describing the differences from other embodiments.

[0060] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.

Claims

1. A comprehensive utilization system based on coal spontaneous combustion and blast furnace tail gas for co-production of H2 and CO, characterized in that, It includes a coal spontaneous combustion controlled reaction and hydrocarbon collection unit, a hydrocarbon gas catalytic cracking hydrogen production unit, a hydrogen compression storage and blast furnace hydrogen-rich injection unit, a blast furnace gas purification and component separation and blending unit, and a central intelligent control and optimization platform, all connected sequentially by pipelines. The injection end of the hydrogen compression storage and blast furnace hydrogen-rich injection unit is connected to the tuyeres of the blast furnace. The gas outlet of the blast furnace is connected to the gas inlet of the blast furnace gas purification and component separation and blending unit through a pipeline. The inert gas outlet of the blast furnace gas purification and component separation and blending unit is connected to the gas injection port of the coal spontaneous combustion controlled reaction and hydrocarbon collection unit through a pipeline, forming a closed material circulation loop of coal spontaneous combustion directional hydrocarbon production, hydrocarbon cracking hydrogen production, hydrogen-rich blast furnace ironmaking, and blast furnace tail gas circulation regulation of coal spontaneous combustion. The central intelligent control and optimization platform is connected to the controlled reaction of coal spontaneous combustion and hydrocarbon collection unit, the catalytic cracking of hydrocarbon gas to produce hydrogen unit, the hydrogen compression storage and blast furnace hydrogen-rich injection unit, and the blast furnace gas purification and component separation and blending unit. It is used to collect real-time operating data of each unit, dynamically adjust the operating parameters of each unit, coordinate the material and energy balance of the system, and execute global safety interlocks.

2. The system of claim 1, wherein, The controlled reaction and hydrocarbon collection unit for spontaneous combustion of coal includes a coal seam simulation reactor with programmable temperature control, a multi-channel gas injection and distribution system, and a real-time online monitoring module. The multi-channel gas injection and distribution system is used to inject a mixture of air and inert gas into the coal seam simulation reactor. The real-time online monitoring module includes a gas composition monitoring sensor and a temperature monitoring sensor, which are used to monitor the concentrations of oxygen, carbon monoxide, ethane, and propane, as well as the temperature of the coal body in the reactor in real time.

3. The system of claim 2, wherein, The hydrocarbon gas catalytic cracking hydrogen production unit includes a feed gas pretreatment subsystem, a catalytic pyrolysis reactor, and a hydrogen separation and purification device connected in sequence. The feed gas pretreatment subsystem is used to remove dust and desulfurize hydrocarbon-rich gases. The catalytic pyrolysis reactor is loaded with a nickel-based catalyst or a carbon-based catalyst to catalytically crack ethane and propane into hydrogen and solid carbon. The hydrogen separation and purification device is a pressure swing adsorption (PSA) device used to separate and purify high-purity hydrogen.

4. The system of claim 3, wherein, The hydrogen compression storage and blast furnace hydrogen-rich injection unit includes a hydrogen compressor, a hydrogen storage device, and a blast furnace injection subsystem connected in sequence. The blast furnace injection subsystem includes a safety injection and mixing component and a dedicated spray gun. The dedicated spray gun is connected to the tuyeres of the blast furnace and is used to inject pressurized high-purity hydrogen into the blast furnace.

5. The system of claim 4, wherein, The blast furnace gas purification and component separation and blending unit includes a dust removal and desulfurization device, a CO2 capture device, and a gas separation device connected in sequence. The gas separation device is a gas distillation device or a membrane separation device, used to separate the treated blast furnace gas into CO-rich gas, inert gas, and other tail gas. The outlet of the CO-rich gas is connected to the blast furnace inlet or a chemical synthesis pipeline, and the outlet of the inert gas is connected to the gas injection port of the controlled coal combustion reaction and hydrocarbon collection unit. The main components of the inert gas are nitrogen and uncaptured carbon dioxide.

6. The system of claim 5, wherein, The central intelligent control and optimization platform has a built-in trained machine learning model and process control algorithm. The machine learning model is a random forest model. The core control parameters of the central intelligent control and optimization platform include the reaction temperature of the controlled coal combustion reaction and hydrocarbon collection unit, the inert gas injection ratio, the gas flow rate, the reaction temperature of the hydrocarbon gas catalytic cracking hydrogen production unit, and the gas separation ratio of the blast furnace gas purification and component separation and blending unit.

7. A comprehensive utilization method for co-production of H2 and CO based on coal spontaneous combustion and blast furnace tail gas circulation, characterized in that, include: Coal with a tendency to spontaneously combust is placed in a coal spontaneous combustion reactor, and inert gas from blast furnace tail gas is introduced and injected into the coal seam along with air in a controllable proportion to inhibit the violent oxidation of the coal and create a low-temperature pyrolysis environment for the coal. The composition of the outlet gas and the temperature of the coal seam reaction are monitored online. Based on the coal quality characteristics and real-time monitoring data, the temperature, gas flow rate and the ratio of inert gas to air in the coal seam reaction are dynamically adjusted to ensure that the coal spontaneous combustion reaction operates stably in a high hydrocarbon production mode and continuously produces hydrocarbon-rich gas rich in ethane and propane. After pretreatment, the hydrocarbon-rich gas is fed into a catalytic pyrolysis reactor, where it undergoes a cracking reaction at 550-850℃ with the help of a catalyst to produce hydrogen and solid carbon. After separation and purification, high-purity hydrogen is obtained, and solid carbon by-products are collected at the same time. High-purity hydrogen is pressurized and injected into the blast furnace tuyeres through a special spray gun. The hydrogen burns in the blast furnace to provide heat and acts as a reducing agent to participate in the reduction reaction of iron oxides, replacing part of the coke and pulverized coal, thereby reducing the blast furnace coke ratio and carbon emissions. Blast furnace gas produced by the blast furnace is collected, purified and decarbonized, and then separated into a CO-rich gas stream and an inert gas stream. The CO-rich gas stream is returned to the blast furnace for recycling or supplied as a chemical raw material, while the inert gas stream is transported back to the coal seam reaction stage as a medium to regulate the intensity of the coal auto-combustion reaction, thus completing a closed material cycle. Continuously collect operational data from the entire system, predict the operational trends of key system nodes through models, and automatically fine-tune the operational parameters of each link through feedback control.

8. The method of claim 7, wherein, The optimization target of the high hydrocarbon production mode is that the ethane concentration is greater than 200 ppm and the propane concentration is greater than 110 ppm, while controlling the oxygen concentration in the coal seam and the core temperature of the coal body below the preset safety threshold; the coal quality characteristics include the BET surface area of ​​the coal.

9. The method of claim 8, wherein, The key nodes include hydrocarbon yield, hydrogen yield, blast furnace fuel ratio, and tail gas composition; the operating parameters include the composition of the injected gas for coal seam reaction, the temperature of catalytic pyrolysis reaction, and the gas separation ratio of blast furnace gas.

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