A hydrogen-rich carbon cycle blast furnace combustion efficiency optimization method based on a pulverized coal-gas multi-element competitive combustion mechanism

Abstract

The application belongs to the field of low-carbon metallurgical technology, and specifically discloses a hydrogen-rich carbon cycle blast furnace combustion efficiency optimization method based on a coal powder-coal gas multi-element competitive combustion mechanism, which comprises the following steps: firstly, a multi-element competitive combustion reaction network model is constructed; then, key regulation parameters and a target function are determined; next, the influence mechanism of the key regulation parameters is analyzed; and finally, an optimization regulation strategy is formulated. In view of the problem that oxygen competition between coal gas and coal powder in the tuyere area of the hydrogen-rich carbon cycle blast furnace leads to a decrease in the coal powder burnout rate, the application builds a multi-element competitive combustion mechanism model, clearly defines the mutual influence relationship of each reaction path, and then proposes a blowing parameter synergistic regulation strategy with the goal of optimizing the coal powder burnout rate and the efficient utilization of coal gas chemical energy, so as to realize the synergistic optimization of the coal powder burnout rate and the utilization rate of coal gas chemical energy under different furnace conditions, and solve the problem that oxygen competition between coal gas and coal powder in the tuyere area of the hydrogen-rich carbon cycle blast furnace leads to coal powder combustion lag and a decrease in the coal powder burnout rate.

Description

Technical Field

[0001] This invention relates to the field of low-carbon metallurgical technology, specifically to a method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas. Background Technology

[0002] Under the development trend of the steel industry towards low-carbon and high-efficiency transformation, the hydrogen-rich carbon-recycled oxygen blast furnace, with its core characteristics of pure oxygen combustion and gas recycling, has become an important development direction for blast furnace ironmaking technology innovation. The core process feature of this technology is the multi-element synergistic injection of pulverized coal, circulating gas (rich in CO, H2, CH4), and pure oxygen in the blast furnace tuyeres area. Compared with the traditional pulverized coal-hot blast combustion system, it fundamentally changes the combustion reaction environment in the tuyeres area, forming a unique multi-element competitive combustion mechanism of pulverized coal and gas.

[0003] In the tuyere vortex zone of a hydrogen-rich carbon circulating blast furnace, the combustible components such as CO, H2, and CH4 in the circulating gas have a much higher reactivity than pulverized coal. Upon contact with pure oxygen, they preferentially undergo oxidation combustion, releasing a large amount of heat in a short time and rapidly reshaping the temperature field and component distribution in the zone. This reactivity characteristic creates a significant core contradiction in the combustion process of the tuyere zone: oxygen, as a common reactant in the combustion of gas components, the combustion of volatiles after pulverized coal pyrolysis, and the combustion of residual coke, is preferentially consumed by the gas, resulting in insufficient oxygen supply for pulverized coal combustion and consequently, delayed pulverized coal combustion. This delayed combustion directly leads to incomplete pyrolysis, volatile matter release, and residual coke gasification processes, ultimately causing a significant decrease in pulverized coal burnout rate, with a large amount of unburned pulverized coal entering the hearth with the gas flow. Unburned pulverized coal not only causes a serious waste of carbon resources and increases blast furnace fuel consumption, but also interacts adversely with slag, reducing slag fluidity, deteriorating slag desulfurization, dephosphorization and other metallurgical properties, further interfering with the descent of the blast furnace charge column and the rational distribution of gas flow, disrupting the smooth operation of the blast furnace, and seriously affecting the stability, continuity and production efficiency of ironmaking.

[0004] Current control methods typically alleviate the oxygen shortage problem in pulverized coal by increasing oxygen supply. However, this leads to the excessive oxidation of combustible components in the coal gas into CO2 and H2O, resulting in the loss of their chemical energy and reducing capacity, thus hindering the indirect reduction and utilization of the coal gas within the furnace. Conversely, simply controlling the oxygen supply to preserve the chemical energy of the coal gas further exacerbates the oxygen shortage in pulverized coal, causing a continuous decline in the pulverized coal burnout rate. Therefore, it is necessary to design a combustion efficiency optimization method for hydrogen-rich carbon cycle blast furnaces based on a multi-element competitive combustion mechanism between pulverized coal and coal gas. This method aims to address the problem of oxygen competition between coal gas and pulverized coal in the tuyeres area of ​​hydrogen-rich carbon cycle blast furnaces, which causes delayed pulverized coal combustion and consequently a decrease in the pulverized coal burnout rate. Summary of the Invention

[0005] The purpose of this invention is to provide a method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, so as to solve the problem that the competition for oxygen between coal gas and pulverized coal in the tuyeres area of ​​the hydrogen-rich carbon cycle blast furnace causes pulverized coal combustion to lag, resulting in a decrease in the pulverized coal burnout rate.

[0006] To achieve the above objectives, the basic solution provided by this invention is: a method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, comprising the following steps: S1: Construct a multi-competitive combustion reaction network model: Identify the key homogeneous and heterogeneous reactions occurring in the tuyeres of a hydrogen-rich carbon circulating blast furnace, and analyze the competitive and synergistic relationships among the reactions to form a combustion mechanism model for the tuyeres of a hydrogen-rich carbon circulating blast furnace. S2: Determine key control parameters and objective functions: Based on the combustion mechanism of the combustion reaction network model in S1 and combined with the competition and synergy of each reaction, determine key control parameters, and clarify the primary and secondary objective functions to form an objective function system with maximizing the pulverized coal burnout rate in the tuyeres of the hydrogen-rich carbon cycle blast furnace as the primary objective and maximizing the utilization rate of coal gas chemical energy as the secondary objective. S3: Influence Mechanism Analysis: Using the CFD model and combined with the combustion mechanism model of the hydrogen-rich carbon circulating blast furnace tuyeres in S1, we analyze the influence of each key control parameter on the multi-element competitive combustion process. S4: Formulate graded optimization control strategies: Based on the impact of key control parameters in S3 on the multi-competitive combustion process, formulate parameter control methods under the objectives of maximum pulverized coal burnout rate, efficient utilization of coal gas chemical energy, and balanced optimization of furnace conditions. S5: Online monitoring and dynamic adjustment: The oxygen concentration at the tuyere, the composition of the gas at the top of the furnace, and the theoretical combustion temperature are monitored through the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere. Then, the pulverized coal burnout rate and the degree of gas combustion are estimated based on the monitoring data. Finally, the estimated results are compared with the target values ​​to fine-tune the molar ratio of circulating gas to oxygen and the temperature of circulating gas.

[0007] The beneficial effects of this invention are as follows: (1) This invention constructs a closed-loop technical system for combustion mechanism modeling, parameter determination, law analysis, strategy formulation, and online control. By constructing a multi-competitive combustion reaction network model of the tuyeres of a hydrogen-rich carbon circulating blast furnace from the perspective of chemical reaction engineering, it accurately defines key homogeneous and heterogeneous reactions such as coal gas combustion and coal powder pyrolysis. At the same time, it clarifies the three core reaction relationships of oxygen competition, heat coupling, and product correlation. Based on this, it conducts parameter influence mechanism analysis, and finally provides a theoretical basis for blast furnace combustion optimization, realizing the synergistic optimization of coal powder burnout rate and coal gas chemical energy utilization rate under different furnace conditions. (2) This invention distinguishes between two different optimization objectives and their corresponding operation directions: improving coal powder burnout rate and improving coal gas chemical energy utilization rate. It avoids the limitations of single index optimization. At the same time, it uses the circulating coal gas to oxygen molar ratio as the core control parameter, and combines auxiliary parameters such as coal gas temperature and coal powder particle size to form a synergistic control scheme, realizing the refined control of the combustion process, and upgrading the blast furnace operation from experience-based adjustment to scientific control.

[0008] Option 2, the preferred option of the basic scheme, involves homogeneous reactions in S1 including combustion of gas components: CO + 1 / 2O2 → CO2, H2 + 1 / 2O2 → H2O, CH4 + 1 / 2O2 → CO + 2H2, and combustion of volatiles: C α H β O γ N δ +O2→CO+H2O+N2; Heterogeneous reactions include: Pulverized coal pyrolysis: Coal → Volatile matter (C α H β O γ N δ + Residual coke, combustion and gasification of residual coke: C + 1 / 2O2 → CO, C + CO2 → 2CO, C + H2O → CO + H2. The key homogeneous and heterogeneous reaction types and specific reaction formulas of multi-element competitive combustion in the tuyere swirl zone of a hydrogen-rich carbon circulating blast furnace were clarified, defining the core constituent units of the combustion mechanism model; a strict distinction was made between homogeneous reactions between the gas phase and heterogeneous reactions between the gas and solid phases, closely aligning with the actual combustion reaction characteristics of the tuyere zone of a hydrogen-rich carbon circulating blast furnace, laying the foundation for subsequent analysis of the competitive and synergistic relationships between various reactions.

[0009] Option 3, an optimal choice of Option 2, involves the competitive and synergistic relationships among the reactions in S1, including oxygen competition, heat coupling, and product correlation. This ensures that subsequent control strategies revolve around resolving the core contradictions, avoiding blind control. Simultaneously, it integrates the dispersed reactions into an organic system of competition and synergy, clarifying the heat and material correlations between coal gas combustion and pulverized coal combustion. This upgrades the combustion mechanism model from a list of single reactions to a reaction network system, making it more closely aligned with the coupling characteristics of actual combustion.

[0010] Option 4, an optimal choice from the basic option, identifies key control parameters in S2, including the molar ratio of circulating gas to oxygen, circulating gas temperature, oxygen preheating temperature, and pulverized coal particle size distribution. This approach determines the parameters that decisively influence the multi-component competitive combustion process, avoiding interference from secondary parameters.

[0011] Option 5, an optimal choice from Option 4, specifically addresses the influence of the circulating gas to oxygen molar ratio in S3 as follows: When the ratio is too high (insufficient oxygen), combustion is incomplete, heat release is low, and pulverized coal pyrolysis and combustion rates slow down. When the ratio is too low (excessive oxygen), gas and volatiles are over-oxidized, and the high-temperature zone becomes too concentrated. The circulating gas temperature enhances initial combustion intensity and promotes earlier pulverized coal pyrolysis; excessively high temperature leads to premature combustion. Oxygen preheating temperature increases theoretical combustion temperature and strengthens combustion. Pulverized coal particle size increases surface area, resulting in faster reactions. This clarifies the influence, direction, and positive / negative effects of each parameter in the multi-stage competitive combustion process, providing a quantitative mechanism basis for subsequent graded control strategies and avoiding furnace condition problems caused by blind adjustments.

[0012] Option 6, the preferred option based on this, in S4, the operation method for pursuing the highest pulverized coal combustion rate is: moderately reduce the molar ratio of circulating gas to oxygen, increase the oxygen ratio, ensuring that there is surplus oxygen for pulverized coal combustion after the gas combustion is completed, and at the same time, appropriately increase the circulating gas temperature or oxygen preheating temperature; the operation method for pursuing efficient utilization of gas chemical energy is: moderately increase the molar ratio of circulating gas to oxygen, reduce the oxygen ratio, and at the same time, pay attention to whether the pulverized coal combustion rate decreases. If the pulverized coal combustion rate decreases, increase the pulverized coal concentration or optimize the pulverized coal particle size to a finer particle size; the operation method for balanced optimization of the molar ratio of circulating gas to oxygen, gas utilization rate and pulverized coal combustion rate is: based on the theoretical basis provided by the combustion mechanism model and CFD model of the hydrogen-rich carbon circulating blast furnace tuyere zone, combined with the real-time monitoring data provided by the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere and calculate it to obtain the maximum molar ratio of circulating gas to oxygen constrained by the pulverized coal combustion rate, and then adjust the key control parameters according to the obtained maximum molar ratio of circulating gas to oxygen. Different control strategies are developed to meet the production needs of different blast furnaces, adapting to the optimization requirements of different furnace conditions and improving the accuracy and real-time nature of the optimization results.

[0013] Option 7 is the preferred option of Option 6. In S4, the constraint value of pulverized coal combustion rate η_char is greater than 80%. Detailed Implementation

[0014] The present invention will be further described in detail below through specific embodiments: Example 1 A method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas includes the following steps: S1: Constructing a multi-component competitive combustion reaction network model: Identifying the key homogeneous and heterogeneous reactions occurring in the tuyeres of a hydrogen-rich carbon-cycle blast furnace. Homogeneous reactions include combustion of gas components: CO + 1 / 2O2 → CO2, H2 + 1 / 2O2 → H2O, CH4 + 1 / 2O2 → CO + 2H2, and combustion of volatiles: C α H β O γ N δ +O2→CO+H2O+N2; Heterogeneous reactions include pulverized coal pyrolysis: coal → volatile matter (C α H β O γ N δ The combustion and gasification of residual coke are analyzed: C + 1 / 2O2 → CO, C + CO2 → 2CO, C + H2O → CO + H2. Simultaneously, the competitive and synergistic relationships between these reactions are analyzed to form a combustion mechanism model for the tuyeres of a hydrogen-rich carbon-cycle blast furnace. The competitive and synergistic relationships between these reactions include oxygen competition (specifically, oxygen is a reactant in the combustion of coal gas components, volatile matter, and residual coke), thermal coupling (coal gas combustion provides a high-temperature environment for pulverized coal pyrolysis and combustion), and product correlation (coal gas combustion products CO2 and H2O can act as residual coke gasification agents). S2: Determine key control parameters and objective functions: Based on the combustion mechanism of the combustion reaction network model in S1 and combined with the competition and synergy of each reaction, determine the circulating gas to oxygen molar ratio (C / O ratio), circulating gas temperature, oxygen preheating temperature and pulverized coal particle size distribution. At the same time, clarify the primary and secondary objective functions, forming an objective function system with maximizing the pulverized coal burnout rate in the tuyeres of the hydrogen-rich carbon circulating blast furnace as the primary objective, and maximizing the chemical energy utilization rate of the gas and avoiding over-combustion as secondary objectives for CO2 and H2O. S3: Parameter Influence Mechanism Analysis Based on Reaction Kinetics: Using a CFD model combined with the combustion mechanism model of the hydrogen-rich carbon circulating blast furnace tuyeres in S1, the influence of key control parameters on the multi-element competitive combustion process is analyzed. The specific effects of the circulating gas to oxygen molar ratio (C / O ratio) are as follows: When the circulating gas to oxygen molar ratio (C / O ratio) is too high, i.e., insufficient oxygen, the gas combustion is incomplete, less heat is released, and the pyrolysis and combustion rates of pulverized coal slow down; when the circulating gas to oxygen molar ratio (C / O ratio) is too low, i.e., excessive oxygen, the gas and volatiles are over-oxidized, and the high-temperature zone is too concentrated. The specific effects of circulating gas temperature are as follows: Increasing the circulating gas temperature can enhance the initial combustion intensity of the gas and promote the early pyrolysis of pulverized coal; excessively high circulating gas temperature can easily lead to excessively advanced combustion. The effects of oxygen preheating temperature: Preheating oxygen can increase the theoretical combustion temperature and enhance combustion. The effects of pulverized coal particle size are as follows: Fine-particle-size pulverized coal has a larger specific surface area, resulting in a faster reaction. S4: Formulate a graded optimization control strategy: Based on the impact of key control parameters in S3 on the multi-competitive combustion process, formulate parameter control methods under the objectives of maximum pulverized coal burnout rate, efficient utilization of coal gas chemical energy, and balanced optimization of furnace conditions. The operation method for pursuing the maximum pulverized coal burnout rate is: moderately reduce the molar ratio of circulating coal gas to oxygen, increase the oxygen ratio, ensuring that there is surplus oxygen available for pulverized coal combustion after the coal gas combustion is completed, while appropriately increasing the circulating coal gas temperature or oxygen preheating temperature. The operation method for pursuing efficient utilization of coal gas chemical energy is: moderately increase the molar ratio of circulating coal gas to oxygen, and decrease the oxygen ratio... For example, while monitoring whether the pulverized coal burnout rate decreases, if the pulverized coal burnout rate decreases, the pulverized coal concentration is increased or the pulverized coal particle size is optimized to a finer particle size. The operation method for balancing and optimizing the circulating gas to oxygen molar ratio, gas utilization rate and pulverized coal burnout rate is as follows: Based on the theoretical basis provided by the combustion mechanism model and CFD model of the hydrogen-rich carbon circulating blast furnace tuyere zone, combined with the real-time monitoring data provided by the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere and calculated, the pulverized coal burnout rate constraint value η_char>80% is obtained, and then the key control parameters are adjusted according to the obtained maximum circulating gas to oxygen molar ratio. S5: Online monitoring and dynamic adjustment: The oxygen concentration at the tuyere, the composition of the gas at the top of the furnace, and the theoretical combustion temperature are monitored through the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere. Then, the pulverized coal burnout rate and the degree of gas combustion are estimated based on the monitoring data. Finally, the estimated results are compared with the target values ​​to fine-tune the molar ratio of circulating gas to oxygen and the temperature of circulating gas.

[0015] Option 2 A method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas is described. The steps are identical to those in Example 1, except that: S2: Because the current furnace condition shows that the indirect reduction in the furnace body is strong, we pursue the efficient utilization of the chemical energy of the coal gas. Under the premise of ensuring that the coal powder combustion rate is >75%, we increase the CO+H2 content in the tuyere gas. S3: Under initial operating conditions, the molar ratio of circulating gas to oxygen (C / O ratio) is 2.2, the circulating gas temperature is 1200℃, the simulated pulverized coal combustion rate is 82%, and the volume fraction of CO+H2 in the tuyere gas is 85%. S4: To pursue efficient utilization of coal gas chemical energy, when the molar ratio of circulating coal gas to oxygen (C / O ratio) is increased to 2.5, the CFD model shows that the pulverized coal combustion rate drops to 78%, but still meets the requirement of >75%. Meanwhile, the volume fraction of CO+H2 in the tuyere gas rises to 88%. At this point, to compensate for the possible weakening of combustion intensity due to the increased molar ratio of circulating coal gas to oxygen, the circulating coal gas temperature is increased to 1250℃. After adjustment, the CFD model shows that the pulverized coal combustion rate recovers to 80%, and the volume fraction of CO+H2 is 87.5%. S5: The online monitoring system for the hydrogen-rich carbon cycle blast furnace tuyeres shows that the theoretical combustion temperature dropped from 2050℃ to 1980℃ after adjustment, and the CO content in the top gas increased by 1.5%. Through sampling analysis, the measured pulverized coal burnout rate at the boundary of the swirling zone was 79%.

[0016] Option 3 A method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas is described. The steps are identical to those in Example 2, except that: S2: Due to the poor coal quality and low volatile matter in the current furnace, the goal is to achieve the highest pulverized coal combustion rate. Under the premise of ensuring that the pulverized coal combustion rate is >85%, the molar ratio of circulating gas to oxygen is reduced. S3: Pulverized coal particle size ≤80μm, oxygen preheating temperature 800℃; S4: In pursuit of the highest pulverized coal combustion rate, when the molar ratio of circulating gas to oxygen (C / O ratio) is reduced to 1.8, the CFD model shows that the pulverized coal combustion rate increases to 88%. After increasing the circulating gas temperature to 1300℃, the residual coke gasification rate increases by 15%. S5: The online monitoring system for the hydrogen-rich carbon cycle blast furnace tuyeres shows that the theoretical combustion temperature has increased from 2050℃ to 2150℃ after adjustment.

[0017] Option 4 A method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas is described. The steps are identical to those in Example 2, except that: S2: Due to the high requirements for smooth operation of the blast furnace, it is necessary to take into account both the pulverized coal burnout rate and the efficient utilization of coal gas chemical energy. Under the premise of ensuring that the pulverized coal burnout rate is >80%, the utilization rate of coal gas chemical energy should be improved. S3: Pulverized coal particle size is 90μm, oxygen preheating temperature is 700℃; S4: When the molar ratio of circulating gas to oxygen (C / O ratio) is reduced to 2.0, the CFD model shows that the pulverized coal combustion rate increases to 83%, while the volume fraction of CO+H2 in the tuyere gas increases to 86%. After raising the circulating gas temperature to 1220℃, the fuel ratio is reduced by 2.5% compared to the traditional method.

[0018] In summary, by constructing a multi-competitive combustion reaction network model, clarifying key control parameters and objective functions, and combining this with CFD model analysis of parameter influence mechanisms, we not only ensured the supply of oxygen and high-temperature environment for pulverized coal combustion in the tuyeres of the hydrogen-rich carbon cycle blast furnace, but also precisely controlled the degree of gas combustion, avoiding excessive loss of gas chemical energy. Furthermore, by formulating a graded optimization control strategy and simultaneously conducting online monitoring and dynamic adjustments, we achieved synergistic optimization of pulverized coal burnout rate and gas chemical energy utilization rate under different furnace conditions. This upgraded blast furnace combustion control from experience-based operation to scientific and precise management, ultimately achieving efficient pulverized coal burnout in the blast furnace, significantly improving the overall combustion efficiency of the hydrogen-rich carbon cycle blast furnace, and simultaneously enhancing the energy efficiency and carbon emission reduction targets of ironmaking production, ensuring the long-term stable operation of the blast furnace.

[0019] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, characterized in that, Includes the following steps: S1: Construct a multi-competitive combustion reaction network model: Identify the key homogeneous and heterogeneous reactions occurring in the tuyeres of a hydrogen-rich carbon circulating blast furnace, and analyze the competitive and synergistic relationships among the reactions to form a combustion mechanism model for the tuyeres of a hydrogen-rich carbon circulating blast furnace. S2: Determine key control parameters and objective functions: Based on the combustion mechanism of the combustion reaction network model in S1 and combined with the competition and synergy of each reaction, determine key control parameters, and clarify the primary and secondary objective functions to form an objective function system with maximizing the pulverized coal burnout rate in the tuyeres of the hydrogen-rich carbon cycle blast furnace as the primary objective and maximizing the utilization rate of coal gas chemical energy as the secondary objective. S3: Influence Mechanism Analysis of Key Control Parameters: Using a CFD model and combined with the combustion mechanism model of the hydrogen-rich carbon circulating blast furnace tuyeres in S1, the influence of each key control parameter on the multi-element competitive combustion process is analyzed. S4: Formulate graded optimization control strategies: Based on the impact of key control parameters in S3 on the multi-competitive combustion process, formulate parameter control methods under the objectives of maximum pulverized coal burnout rate, efficient utilization of coal gas chemical energy, and balanced optimization of furnace conditions. S5: Online monitoring and dynamic adjustment: The oxygen concentration at the tuyere, the composition of the gas at the top of the furnace, and the theoretical combustion temperature are monitored through the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere. Then, the pulverized coal burnout rate and the degree of gas combustion are estimated based on the monitoring data. Finally, the estimated results are compared with the target values ​​to fine-tune the molar ratio of circulating gas to oxygen and the temperature of circulating gas.

2. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 1, is characterized in that... In S1, homogeneous reactions include combustion of gas components: CO + 1 / 2O2 → CO2, H2 + 1 / 2O2 → H2O, CH4 + 1 / 2O2 → CO + 2H2 and combustion of volatiles: C α H β O γ N δ +O2→CO+H2O+N2; Heterogeneous reactions include: Pulverized coal pyrolysis: Coal → Volatile matter + Residual coke, Residual coke combustion and gasification: C+1 / 2O2→CO, C+CO2→2CO, C+H2O→CO+H2.

3. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 2, is characterized in that... In S1, the competitive and cooperative relationships between the reactions include oxygen competition, thermal coupling, and product correlation.

4. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 1, is characterized in that... In S2, key control parameters include the molar ratio of circulating gas to oxygen, circulating gas temperature, oxygen preheating temperature, and coal powder particle size distribution.

5. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 4, is characterized in that... In S3, the effects of the circulating gas to oxygen molar ratio are specifically manifested as follows: when the circulating gas to oxygen molar ratio is too high, i.e., when oxygen is insufficient, the gas combustion is incomplete, less heat is released, and the pyrolysis and combustion rate of pulverized coal slows down; when the circulating gas to oxygen molar ratio is too low, i.e., when oxygen is excessive, the gas and volatiles are over-oxidized and the high-temperature zone is too concentrated. The effects of circulating gas temperature are specifically manifested as follows: increasing the circulating gas temperature can enhance the initial intensity of gas combustion and promote the early pyrolysis of pulverized coal, while excessively high circulating gas temperature can easily cause combustion to be too early. The effects of oxygen preheating temperature: preheating oxygen can increase the theoretical combustion temperature and enhance combustion. The effects of pulverized coal particle size are specifically manifested as follows: fine-particle-size pulverized coal has a larger specific surface area, resulting in a faster reaction.

6. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 1, is characterized in that... In S4, the operation method for pursuing the highest pulverized coal combustion rate is: moderately reduce the molar ratio of circulating gas to oxygen, increase the oxygen ratio, and ensure that there is surplus oxygen available for pulverized coal combustion after the gas combustion is completed. At the same time, the circulating gas temperature or oxygen preheating temperature should be appropriately increased. The operation method for pursuing efficient utilization of gas chemical energy is: moderately increase the molar ratio of circulating gas to oxygen, reduce the oxygen ratio, and pay attention to whether the pulverized coal combustion rate decreases. If the pulverized coal combustion rate decreases, the pulverized coal concentration should be increased or the pulverized coal particle size should be optimized to a finer particle size. The operation method for balanced optimization of the molar ratio of circulating gas to oxygen, gas utilization rate, and pulverized coal combustion rate is: based on the theoretical basis provided by the combustion mechanism model and CFD model of the hydrogen-rich carbon circulating blast furnace tuyere zone, combined with the real-time monitoring data provided by the online monitoring system of the hydrogen-rich carbon circulating blast furnace tuyere, and calculate the maximum molar ratio of circulating gas to oxygen constrained by the pulverized coal combustion rate, and then adjust the key control parameters according to the obtained maximum molar ratio of circulating gas to oxygen.

7. The method for optimizing the combustion efficiency of a hydrogen-rich carbon cycle blast furnace based on a multi-element competitive combustion mechanism of pulverized coal and coal gas, as described in claim 6, is characterized in that... In S4, the constraint value for pulverized coal burnout rate is η_char > 80%.