Method for determining optimal injection range based on energy mass model of shale gas blast furnace

Abstract

The invention discloses an optimal injection range determination method based on a shale gas blast furnace energy mass model. The method comprises the following steps: S1, obtaining an optimal data initial injection range of a shale gas vanadium-titanium blast furnace; s2, setting shale gas components and injection quantity, determining the replacement ratio of the shale gas to coke and coal powder, and calculating the direct reduction degree of iron; s3, constructing a vanadium titano-magnetite blast furnace hydrogen-rich injection energy mass balance model, establishing a reasonable operation window, and determining an optimal injection range; and S4, verifying the optimal blowing range by using a Rist operation line module. Through mutual cooperation of the modules, the optimal injection range of the vanadium titano-magnetite blast furnace injection shale gas under different working conditions is determined, the optimal injection range of the vanadium titano-magnetite blast furnace injection shale gas under different working conditions is accurately determined, the energy utilization efficiency is improved, and the production cost and carbon emission are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of blast furnace ironmaking, and in particular to a method for determining an optimal injection range based on a shale gas blast furnace energy quality model. Background Art

[0002] In the steel industry's blast furnace ironmaking process, finding efficient and economical ways to utilize energy has always been a key demand for the industry's development. As the steel industry continues to expand, pressure on the supply of traditional energy sources and environmental issues have become increasingly prominent. Shale gas, a clean, abundant, and unconventional energy source, if properly utilized in blast furnace ironmaking, can alleviate the energy crisis to a certain extent and contribute to the steel industry's green transformation. Injecting shale gas into the blast furnace optimizes chemical reactions within the furnace, improving ironmaking efficiency while reducing reliance on traditional fossil fuels and lowering carbon emissions.

[0003] Traditional blast furnace ironmaking technology typically uses empirical methods or simple calculation models to determine the injection rate for fuel. This approach relies primarily on the operator's accumulated practical experience, roughly adjusting the injection rate based on the blast furnace's operating conditions. For example, when observing fluctuations in furnace temperature or changes in molten iron quality, the injection rate is increased or decreased based on experience. This approach offers the advantage of relative simplicity and the accumulation of experience in adapting to specific operating conditions through long-term practice. However, this approach has significant drawbacks. Due to the lack of precise calculations and scientific modeling, the injection rate is often not accurately determined, making it difficult to achieve optimal energy utilization in the blast furnace ironmaking process. Excessive injection leads to fuel waste and increased costs, while also affecting the chemical reaction balance within the blast furnace and reducing molten iron quality. Insufficient injection prevents the blast furnace from fully realizing its production potential, resulting in low production efficiency. Furthermore, empirical methods struggle to adapt to rapid changes in blast furnace operating conditions and cannot adjust injection strategies in a timely manner, making it difficult to effectively ensure the stability and economic efficiency of the blast furnace ironmaking process.

[0004] Existing shale gas injection in vanadium-titanium magnetite blast furnaces replaces traditional pulverized coal with oxygen-enriched blast, often leading to a decrease in theoretical combustion temperature and an increase in top gas temperature. However, shale gas injection in the tuyere significantly increases the H2 content in the tuyere combustion zone, enhancing the gas reduction potential and strengthening the reduction of iron-containing charge materials. This reduces the direct reduction degree, resulting in improved ironmaking efficiency and reduced fuel consumption, particularly reducing the demand for solid fuels such as coke and pulverized coal. This process increases the indirect reduction potential within the furnace, promotes indirect reduction, and reduces the solid fuel ratio. However, due to the use of oxygen-enriched blast, the amount of gas in the furnace is reduced. Due to the heat utilization efficiency of the entire furnace body under shale gas injection conditions, the flow field and temperature field in the furnace need to be optimized. However, due to production parameters, the furnace top gas temperature is often too high. Excessively high furnace top temperatures are detrimental to vanadium-titanium magnetite blast furnace production. Too high a temperature will increase heat loss within the furnace, increase the coke ratio, and shorten the service life of the furnace top charging equipment. Too low a temperature will cause the gas temperature to fall below the dew point, easily causing dust to clog the filter cloth, causing it to lose its filtering function and significantly reducing dust removal efficiency. The theoretical combustion temperature of the furnace is reduced and remains at a low temperature for a long time. Too low a theoretical combustion temperature will reduce the replacement ratio, increase the fuel ratio, and even lead to worsening furnace conditions.

[0005] To solve the above problems, the present invention proposes a method for determining the optimal injection range based on the shale gas blast furnace energy quality model. Summary of the Invention

[0006] Based on the above content, the present application provides a method for determining the optimal injection range based on a shale gas blast furnace energy quality model, comprising the following steps:

[0007] S1. Obtaining data to determine the optimal initial injection range for a shale gas vanadium titanium blast furnace;

[0008] S2. Set the shale gas composition and injection rate, determine the replacement ratio of shale gas to coke and pulverized coal, and calculate the direct reduction degree of iron;

[0009] S3. Construct an energy-mass balance model for hydrogen-rich injection in a vanadium-titanium magnetite blast furnace, establish a reasonable operating window, and determine the optimal injection range;

[0010] S4. Verify the optimal injection range through the Rist operation line module in the energy and mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace.

[0011] Preferably, the energy and mass balance model of hydrogen-rich injection in the vanadium-titanium magnetite blast furnace in S3 includes a material balance module, a heat balance module, a substitution ratio module, an operation window module and a Rist operation line module;

[0012] The material balance module calculates the balance of elements and components in molten iron, slag, blast air, hearth, and top gas, determines the material balance results, and provides material basis data for the heat balance module;

[0013] The heat balance module calculates the heat balance data of the whole furnace, high temperature zone and low temperature zone based on the material balance results;

[0014] The replacement ratio module combines material balance results and heat balance data to calculate the ratio of hydrogen-rich gas replacing coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, and feeds it back to the operation window module;

[0015] The operation window module adjusts the corresponding relationship between oxygen enrichment and injection amount in the blast to ensure stable operation of the blast furnace under different conditions through a reasonable operation window, and provides the boundary conditions of the optimal injection range;

[0016] The Rist operation line module verifies the optimal injection range by analyzing the blast furnace ironmaking process, and provides evaluation indicators and optimization directions for determining the optimal injection range;

[0017] The energy-mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace determines the optimal injection range of shale gas in a vanadium-titanium magnetite blast furnace under different working conditions through the cooperation of modules.

[0018] Preferably, the material balance module performs balance calculations on the elements and components in the molten iron, slag, blast air, hearth, and top gas to determine the material balance result, specifically comprising the following steps:

[0019] S3.1.1. Calculate the ore and flux consumption based on the iron balance principle, taking into account the iron content and distribution ratio in the raw materials and the expected target composition of the molten iron, and using the material conservation algorithm.

[0020] S3.1.2. Based on the determined ore and flux consumption, taking into account their respective chemical compositions and chemical reactions during the blast furnace smelting process, and according to the law of conservation of elements, calculate the slag production and determine the contents of the main components of the slag, namely MgO, Al2O3, CaO, and SiO2;

[0021] S3.1.3. Obtain the initial content of each element in the ore, flux, and other raw materials. Based on the iron balance results and the transformation laws in the smelting reaction, combined with the principles of thermodynamics and kinetics, calculate the composition of Fe, C, Si, and Mn elements in the pig iron;

[0022] S3.1.4. Consider the composition of pig iron, slag, and the gas reactions and heat exchange information involved in the smelting process, and establish a gas balance-thermodynamic calculation model to determine the blast volume required to meet the smelting process requirements;

[0023] S3.1.5. Calculate the corresponding direct reduction degree based on the blast volume and the composition of the injected shale gas. Considering the generation and conversion of CO, CO2, H2, and CH4 gases, and using the principles of gas reaction equilibrium and the law of conservation of matter, calculate the composition of each component in the top gas and the total amount of gas.

[0024] S3.1.6. The calculated data on ore, flux, slag, pig iron, blast air, and top gas shall be classified, summarized, and organized according to the type of substance, elemental composition, and quantitative relationship, and a material balance sheet shall be prepared.

[0025] Preferably, the calculation process of the heat balance module is as follows:

[0026] S3.2.1. Obtain the chemical reaction heat of the raw materials and fuels, the physical sensible heat of each substance, the input and output values of the blast and injection energies in the blast furnace, perform a heat balance calculation for the entire furnace, and obtain the heat loss;

[0027] S3.2.2. Compare the heat loss obtained with the set standard to determine whether the heat loss is constant. If not, adjust the parameters and recalculate until the heat loss meets the constant requirement.

[0028] S3.2.3. Calculate the theoretical combustion temperature for the high-temperature zone of the blast furnace, assuming constant heat loss, taking into account the heat released by the fuel combustion reaction and the energy transfer and exchange within the zone;

[0029] S3.2.4. Calculate the furnace top gas temperature based on the heat exchange mechanism in the low-temperature zone, taking into account the heat transfer between the furnace gas and the material and the energy distribution state;

[0030] S3.2.5. Determine the reasonable theoretical combustion temperature and top gas temperature range based on the original raw material and fuel conditions of the blast furnace. Determine the original blast oxygen enrichment conditions of the charge based on the theoretical combustion temperature and top gas temperature calculated previously, and establish a mathematical model for the corresponding operation window.

[0031] Preferably, if the S3.2.2 is not constant, the parameters are adjusted and recalculated. The parameters include blast parameters, injection parameters and raw fuel parameters, which are adjusted according to the material data provided by the material balance module; the blast parameters are adjusted to include blast temperature, humidity, and oxygen enrichment rate; the injection parameters are adjusted to include shale gas injection range and component ratio; the raw fuel parameters are adjusted to include the calorific value and volatile matter content of coke and coal powder, and the heat input and output of each part are recalculated according to the heat balance until the heat loss reaches a constant state.

[0032] Preferably, the replacement ratio module includes a direct reduction unit, a hydrogen-rich gas replacement coke unit, and a hydrogen-rich gas replacement coal powder unit;

[0033] The direct reduction degree unit calculates the direct reduction degree of blast furnace iron based on the reaction path and distribution of iron elements in the blast furnace, combined with the element content of each substance in the material balance and the influence of heat reaction in the heat balance;

[0034] The hydrogen-rich gas replacement coke unit calculates the ratio of hydrogen-rich gas to coke by analyzing the chemical reactions between hydrogen-rich gas and coke in the blast furnace, their ability to provide heat and reducing gas, and combining the material input determined by the material balance results and the heat demand reflected by the heat balance data.

[0035] The hydrogen-rich gas replacement pulverized coal unit calculates the ratio of hydrogen-rich gas to pulverized coal based on the reaction characteristics and energy contribution of hydrogen-rich gas and pulverized coal in the furnace, combined with material balance and heat balance data;

[0036] By feeding back the calculated ratio of hydrogen-rich gas replacing coke and pulverized coal and the direct reduction degree of blast furnace iron to the operation window module, key data are provided for determining a reasonable operation window.

[0037] Preferably, the operation window module includes a raceway theoretical combustion temperature unit and a furnace top gas temperature unit;

[0038] The raceway theoretical combustion temperature unit simulates the fuel combustion process in the raceway based on the heat data provided by the heat balance module, the material input information of the material balance module, and the reaction parameters of the substitution ratio module, calculates the theoretical combustion temperature, and obtains the feasible range of blast oxygen enrichment and injection rate under the theoretical combustion temperature;

[0039] The top gas temperature unit calculates the top gas temperature based on the heat exchange conditions of the entire furnace, gas composition and flow data, and evaluates the thermal status of the upper part of the blast furnace and the gas energy utilization rate;

[0040] The reasonable operation window is comprehensively determined by the theoretical combustion temperature unit of the raceway zone and the furnace top gas temperature unit. Based on the temperature boundaries under different working conditions, the correspondence between oxygen enrichment and injection amount in the blast is dynamically adjusted to provide boundary conditions for determining the optimal injection range.

[0041] Preferably, the reaction parameters of the substitution ratio module include the content of each substance element in the material balance, the reaction heat of the reaction in the substitution ratio module, the amount and proportion of the substance participating in the reaction, and the reaction rate data; each substance includes ore, fuel, and blast; ore includes compounds corresponding to iron, calcium, and silicon elements; fuel includes substances corresponding to carbon and hydrogen elements; and blast includes oxygen and nitrogen.

[0042] Preferably, the Rist operating line module includes an operating line unit, a coke saving potential unit and a furnace efficiency unit;

[0043] The operating line unit is based on material balance and heat balance, combined with the chemical reaction and transmission process of various substances in the blast furnace, to intuitively display the progress and status of the redox reaction in the blast furnace;

[0044] The coke saving potential unit analyzes the potential space for reducing coke consumption by improving the reaction path and energy utilization under hydrogen-rich injection conditions based on the results of the operating line unit;

[0045] The furnace efficiency unit evaluates the effectiveness of heat transfer and reduction reaction in the furnace;

[0046] The operating line unit identifies the key nodes and states of the reaction in the blast furnace, the coke saving potential unit points out the direction of reducing coke usage, and the furnace body efficiency unit reflects the working performance of the furnace body. Through comprehensive analysis of the blast furnace ironmaking process, it provides the degree of coke saving, reaction efficiency evaluation indicators, and optimization directions for adjusting the injection range and optimizing operating parameters to determine the most suitable injection amount.

[0047] Preferably, the optimal injection range is determined by the energy and mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace, specifically including:

[0048] S3.1. Calculate the element and component data of molten iron, slag, blast air, hearth, and top gas through the material balance module to form the material basis.

[0049] S3.2. Use the heat balance module to calculate the heat balance data of the entire furnace, high temperature zone, and low temperature zone to provide energy data support for other modules;

[0050] S3.3. The replacement ratio module uses data from the material balance module and the heat balance module to calculate the ratio of hydrogen-rich gas replacement of coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, through the direct reduction degree unit, the hydrogen-rich gas replacement of coke unit, and the hydrogen-rich gas replacement of pulverized coal unit. This calculation is then fed back to the operation window module.

[0051] S3.4. The operation window module uses the raceway theoretical combustion temperature unit and the furnace top gas temperature unit, combined with data from the material balance module, heat balance module, and displacement ratio module, to determine the feasible range and boundary conditions for blast oxygen enrichment and injection rate under different operating conditions.

[0052] S3.5. Use the Rist operating line module to analyze the blast furnace ironmaking process through the operating line unit, coke saving potential unit and furnace body efficiency unit, provide evaluation indicators and optimization directions, iterate the data of each module, and dynamically adjust the injection range based on the boundary conditions of the operating window module and the evaluation optimization direction of the Rist operating line module until the constraints of stable operation and efficient production of the blast furnace are met, and determine the optimal injection range of shale gas injection in the vanadium-titanium magnetite blast furnace under different working conditions.

[0053] Compared with the prior art, the technical solution of this application has the following technical effects:

[0054] The present invention improves the energy utilization efficiency of the blast furnace ironmaking process. In traditional blast furnace ironmaking, the determination of the injection range lacks an accurate basis, resulting in energy waste or insufficient supply. The present invention uses a material balance module to accurately calculate the elements and components of various substances such as molten iron, slag, and blast, providing a solid foundation for heat balance calculations. Based on these data, the heat balance module accurately calculates the heat balance data of the entire furnace, high temperature zone, and low temperature zone, and clearly grasps the input and output of energy. The replacement ratio module further combines material and heat balance data to calculate the ratio of hydrogen-rich gas to replace coke and coal powder, making energy utilization more reasonable.

[0055] This invention enhances the stability of the blast furnace ironmaking process. The raceway theoretical combustion temperature unit and the top gas temperature unit in the operation window module play a key role. The raceway theoretical combustion temperature unit simulates the fuel combustion process and determines the feasible range of blast oxygen enrichment and injection rate under different operating conditions. The top gas temperature unit assesses the thermal state of the upper part of the blast furnace and the degree of gas energy utilization. Combining these two models, they comprehensively determine a reasonable operation window, providing a guarantee for the stable operation of the blast furnace. When the blast furnace encounters changes in operating conditions such as fluctuations in raw material composition and changes in ambient temperature, the corresponding relationship between blast oxygen enrichment and injection range can be dynamically adjusted based on the operation window determined by these two models.

[0056] The present invention uses the coke-saving potential unit in the Rist operating line module to analyze the potential space for reducing coke consumption under hydrogen-rich injection conditions, guides the blast furnace ironmaking process to be optimized towards reducing coke usage, accurately determines the optimal injection range, and avoids energy waste and additional carbon emissions caused by excessive injection. Shale gas, as a relatively clean energy source, its rational use in blast furnaces also reduces the emission of other pollutants. In this way, while improving ironmaking efficiency, it effectively reduces the negative impact on the environment, helps the steel industry achieve green and sustainable development goals, complies with environmental protection policy requirements, and enhances the social responsibility and market competitiveness of steel companies.

[0057] The present invention can significantly improve the production efficiency and product quality of blast furnace ironmaking. The replacement ratio module accurately calculates the ratio of hydrogen-rich gas replacing coke and pulverized coal and the direct reduction degree of blast furnace iron, providing more reasonable reaction conditions for the blast furnace ironmaking process. The operation window module determines the optimal injection volume boundary conditions, ensuring that the blast furnace operates in the best state. The Rist operation line module provides direction for optimizing blast furnace operating parameters by evaluating indicators such as furnace body efficiency, further promoting the efficient implementation of the blast furnace ironmaking process.

[0058] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiment of the present application in conjunction with the accompanying drawings.

[0059] Based on the detailed description of the specific embodiments of the present application in conjunction with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without inventive work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0061] Figure 1 This is a flow chart of the method for determining the optimal injection range based on the shale gas blast furnace energy quality model;

[0062] Figure 2 This is a model structure diagram of the method for determining the optimal injection range based on the shale gas blast furnace energy quality model;

[0063] Figure 3 Prepare material balance flow chart for material balance module;

[0064] Figure 4 Calculate the flow chart for the heat balance module;

[0065] Figure 5 Flow chart for determining the optimal injection range for the energy-mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace;

[0066] Figure 6 This is the calculation flow chart of the energy and mass balance model for hydrogen-rich injection in a vanadium-titanium magnetite blast furnace;

[0067] Figure 7 Schematic diagram of shale gas injection rate when the hydrogen-rich gas temperature is 25°C and the blast temperature is 1100°C;

[0068] Figure 8 Schematic diagram of shale gas injection rate when the hydrogen-rich gas temperature is 25°C and the blast temperature is 1200°C;

[0069] Figure 9 Schematic diagram of shale gas injection rate when the hydrogen-rich gas temperature is 625℃ and the blast temperature is 1100℃. DETAILED DESCRIPTION

[0070] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. In the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures has been omitted in the embodiments.

[0071] It should be understood that references throughout this specification to "one embodiment" or "this embodiment" mean that a particular feature, structure, or characteristic associated with the embodiment is included in at least one embodiment of the present application. Therefore, the appearance of "one embodiment" or "this embodiment" throughout this specification does not necessarily refer to the same embodiment. Furthermore, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0072] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0073] The term "and / or" in this article only describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another relationship between associated objects, indicating that two relationships may exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0074] The term "at least" in this article only describes the association relationship of associated objects, indicating that there can be three relationships. For example, at least A and B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0075] It should also be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include," "comprises," or any other variations thereof are intended to cover non-exclusive inclusion.

[0076] Example 1

[0077] This embodiment mainly describes the method for determining the optimal injection range based on the shale gas blast furnace energy quality model. Figure 1 As shown, the following steps are included:

[0078] S1. Obtaining data to determine the optimal initial injection range for a shale gas vanadium titanium blast furnace;

[0079] S2. Set the shale gas composition and injection rate, determine the replacement ratio of shale gas to coke and pulverized coal, and calculate the direct reduction degree of iron;

[0080] S3. Construct an energy-mass balance model for hydrogen-rich injection in a vanadium-titanium magnetite blast furnace, establish a reasonable operating window, and determine the optimal injection range;

[0081] S4. Verify the optimal injection range through the Rist operating line module in the energy and mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace;

[0082] The initial data values in S1 include raw fuel data, basic blast data, blast furnace equipment parameters, and preset target molten iron composition data; they also include shale gas characteristic data, the proportions of the main components of methane and hydrogen, and the initially set shale gas injection temperature and pressure parameters;

[0083] When setting the shale gas composition in S2, the volume fractions of the main components of methane CH4 and hydrogen H2 in the shale gas are measured. The shale gas injection rate is initially set to s based on the production scale of the blast furnace and the previous test data. Based on the equivalent relationship between the reducing gas and heat provided in the chemical reaction and the actual reaction conditions in the blast furnace, the direct reduction degree of iron r is calculated. d When, through the formula: Calculate, where is the direct reduction degree at the reference time (without fuel injection); s is the injection amount of reducing substance; λ is the chemical composition coefficient of the injection material, and the formula is: λ = 0.2(C) + 0.9(H), (C) is the content of C atoms in the injection material, which is 0-1, (H) is the content of H atoms in the injection material, which is 0-4, and the natural gas is 2; t0 is the blast temperature, which is 1000℃; φ is the current humidity; the direct reduction degree of iron is calculated by combining the reaction amount of each substance determined by material balance and heat balance.

[0084] like Figure 2 As shown in Figure 3, an energy and mass balance model for hydrogen-rich injection in a vanadium-titanium magnetite blast furnace is constructed to establish a reasonable operating window and determine the most appropriate injection range;

[0085] Furthermore, the energy and mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace includes material balance module, heat balance module, substitution ratio module, operation window module and Rist operation line module;

[0086] The material balance module calculates the balance of elements and components in molten iron, slag, blast air, hearth, and top gas, determines the material balance results, and provides material basis data for the heat balance module;

[0087] The heat balance module calculates the heat balance data of the whole furnace, high temperature zone and low temperature zone based on the material balance results;

[0088] The replacement ratio module combines material balance results and heat balance data to calculate the ratio of hydrogen-rich gas replacing coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, and feeds it back to the operation window module;

[0089] The operation window module adjusts the corresponding relationship between oxygen enrichment and injection amount in the blast to ensure stable operation of the blast furnace under different conditions through a reasonable operation window, and provides the boundary conditions of the optimal injection range;

[0090] The Rist operation line module verifies the optimal injection range by analyzing the blast furnace ironmaking process, and provides evaluation indicators and optimization directions for determining the optimal injection range;

[0091] The energy-mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace determines the optimal injection range of shale gas in a vanadium-titanium magnetite blast furnace under different working conditions through the cooperation of modules.

[0092] Further, if Figure 3 As shown, the material balance module performs balance calculations on the elements and components in molten iron, slag, blast air, hearth, and top gas to determine the material balance results. Specifically, the following steps are included:

[0093] S3.1.1. Calculate the ore and flux consumption based on the iron balance principle, taking into account the iron content and distribution ratio in the raw materials and the expected target composition of the molten iron, and using the material conservation algorithm.

[0094] S3.1.2. Based on the determined ore and flux consumption, taking into account their respective chemical compositions and chemical reactions during the blast furnace smelting process, and according to the law of conservation of elements, calculate the slag production and determine the contents of the main components of the slag, namely MgO, Al2O3, CaO, and SiO2;

[0095] S3.1.3. Obtain the initial content of each element in the ore, flux, and other raw materials. Based on the iron balance results and the transformation laws in the smelting reaction, combined with the principles of thermodynamics and kinetics, calculate the composition of Fe, C, Si, and Mn elements in the pig iron;

[0096] S3.1.4. Consider the composition of pig iron, slag, and the gas reactions and heat exchange information involved in the smelting process, and establish a gas balance-thermodynamic calculation model to determine the blast volume required to meet the smelting process requirements;

[0097] S3.1.5. Calculate the corresponding direct reduction degree based on the blast volume and the composition of the injected shale gas. Considering the generation and conversion of CO, CO2, H2, and CH4 gases, and using the principles of gas reaction equilibrium and the law of conservation of matter, calculate the composition of each component in the top gas and the total amount of gas.

[0098] S3.1.6. The calculated data on ore, flux, slag, pig iron, blast air, and top gas shall be classified, summarized, and organized according to the type of substance, elemental composition, and quantitative relationship, and a material balance sheet shall be prepared.

[0099] In S3.1.4, when establishing the gas balance-thermodynamic calculation model, the main gases involved in the blast furnace smelting reaction are clearly identified. Based on the law of conservation of mass, the changes in the amount of each gas substance before and after the reaction are considered. In combination with the principles of thermodynamics, the Gibbs free energy change ΔG of each gas participating in the reaction is determined. According to the van't Hoff isotherm equation, ΔG = ΔG° + RTln Q l (R is the gas constant, T is the reaction temperature, Q l Calculate the free energy change of the reaction (for the reaction quotient), determine the direction and limit of the reaction; determine the blast volume V that meets the needs of the smelting process g When establishing the formula in It is based on the amount of oxygen required for the smelting reaction and can be determined based on the reaction relationship of each substance in the material balance. is the volume fraction of oxygen in the blast. This formula, combined with the oxygen demand of the reaction in the gas balance-thermodynamic calculation model, is used to calculate the blast volume required to meet the smelting process.

[0100] Further, if Figure 4 As shown, the calculation process of the heat balance module is as follows:

[0101] S3.2.1. Obtain the chemical reaction heat of the raw materials and fuels, the physical sensible heat of each substance, the input and output values of the blast and injection energies in the blast furnace, perform a heat balance calculation for the entire furnace, and obtain the heat loss;

[0102] S3.2.2. Compare the heat loss obtained with the set standard to determine whether the heat loss is constant. If not, adjust the parameters and recalculate until the heat loss meets the constant requirement.

[0103] S3.2.3. Calculate the theoretical combustion temperature for the high-temperature zone of the blast furnace, assuming constant heat loss, taking into account the heat released by the fuel combustion reaction and the energy transfer and exchange within the zone;

[0104] S3.2.4. Calculate the furnace top gas temperature based on the heat exchange mechanism in the low-temperature zone, taking into account the heat transfer between the furnace gas and the material and the energy distribution state;

[0105] S3.2.5. Determine the reasonable theoretical combustion temperature and top gas temperature range based on the original raw material and fuel conditions of the blast furnace. Determine the original blast oxygen enrichment conditions of the charge based on the theoretical combustion temperature and top gas temperature calculated previously, and establish a mathematical model for the corresponding operation window.

[0106] Furthermore, if S3.2.2 is not constant, the parameters are adjusted and recalculated. The parameters include blast parameters, injection parameters and raw fuel parameters, which are adjusted according to the material data provided by the material balance module; the blast parameters include blast temperature, humidity and oxygen enrichment rate; the injection parameters include shale gas injection range and component ratio; the raw fuel parameters include the calorific value and volatile matter content of coke and coal powder, and the heat input and output of each part are recalculated according to the heat balance until the heat loss reaches a constant state.

[0107] Furthermore, the replacement ratio module includes a direct reduction degree unit, a hydrogen-rich gas replacement coke unit, and a hydrogen-rich gas replacement coal powder unit;

[0108] The direct reduction degree unit calculates the direct reduction degree of blast furnace iron based on the reaction path and distribution of iron elements in the blast furnace, combined with the element content of each substance in the material balance and the influence of heat reaction in the heat balance;

[0109] The hydrogen-rich gas replacement coke unit calculates the ratio of hydrogen-rich gas to coke by analyzing the chemical reactions between hydrogen-rich gas and coke in the blast furnace, their ability to provide heat and reducing gas, and combining the material input determined by the material balance results and the heat demand reflected by the heat balance data.

[0110] The hydrogen-rich gas replacement pulverized coal unit calculates the ratio of hydrogen-rich gas to pulverized coal based on the reaction characteristics and energy contribution of hydrogen-rich gas and pulverized coal in the furnace, combined with material balance and heat balance data;

[0111] By feeding back the calculated ratio of hydrogen-rich gas replacing coke and pulverized coal and the direct reduction degree of blast furnace iron to the operation window module, key data are provided for determining a reasonable operation window.

[0112] Furthermore, the operation window module includes a raceway theoretical combustion temperature unit and a furnace top gas temperature unit;

[0113] The raceway theoretical combustion temperature unit simulates the fuel combustion process in the raceway based on the heat data provided by the heat balance module, the material input information of the material balance module, and the reaction parameters of the substitution ratio module, calculates the theoretical combustion temperature, and obtains the feasible range of blast oxygen enrichment and injection rate under the theoretical combustion temperature;

[0114] The top gas temperature unit calculates the top gas temperature based on the heat exchange conditions of the entire furnace, gas composition and flow data, and evaluates the thermal status of the upper part of the blast furnace and the gas energy utilization rate;

[0115] The reasonable operation window is comprehensively determined by the theoretical combustion temperature unit of the raceway zone and the furnace top gas temperature unit. Based on the temperature boundaries under different working conditions, the correspondence between oxygen enrichment and injection amount in the blast is dynamically adjusted to provide boundary conditions for determining the optimal injection range.

[0116] Furthermore, the reaction parameters of the substitution ratio module include the content of each substance element in the material balance, the reaction heat of the reaction in the substitution ratio module, the amount and proportion of the substance participating in the reaction, and the reaction rate data; each substance includes ore, fuel, and blast; ore includes compounds corresponding to iron, calcium, and silicon elements; fuel includes substances corresponding to carbon and hydrogen elements; and blast includes oxygen and nitrogen.

[0117] Furthermore, the Rist operating line module includes an operating line unit, a coke saving potential unit, and a furnace efficiency unit;

[0118] The operating line unit is based on material balance and heat balance, combined with the chemical reaction and transmission process of various substances in the blast furnace, to intuitively display the progress and status of the redox reaction in the blast furnace;

[0119] The coke saving potential unit analyzes the potential space for reducing coke consumption by improving the reaction path and energy utilization under hydrogen-rich injection conditions based on the results of the operating line unit;

[0120] The furnace efficiency unit evaluates the effectiveness of heat transfer and reduction reaction in the furnace;

[0121] The operating line unit identifies the key nodes and states of the reaction in the blast furnace, the coke saving potential unit points out the direction of reducing coke usage, and the furnace body efficiency unit reflects the working performance of the furnace body. Through comprehensive analysis of the blast furnace ironmaking process, it provides the degree of coke saving, reaction efficiency evaluation indicators, and optimization directions for adjusting the injection range and optimizing operating parameters to determine the most suitable injection range.

[0122] Further, if Figure 5 As shown in the figure, the optimal injection range is determined by the energy and mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace, which specifically includes:

[0123] S3.1. Calculate the element and component data of molten iron, slag, blast air, hearth, and top gas through the material balance module to form the material basis.

[0124] S3.2. Use the heat balance module to calculate the heat balance data of the entire furnace, high temperature zone, and low temperature zone to provide energy data support for other modules;

[0125] S3.3. The replacement ratio module uses data from the material balance module and the heat balance module to calculate the ratio of hydrogen-rich gas replacement of coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, through the direct reduction degree unit, the hydrogen-rich gas replacement of coke unit, and the hydrogen-rich gas replacement of pulverized coal unit. This calculation is then fed back to the operation window module.

[0126] S3.4. The operation window module uses the raceway theoretical combustion temperature unit and the furnace top gas temperature unit, combined with data from the material balance module, heat balance module, and displacement ratio module, to determine the feasible range and boundary conditions for blast oxygen enrichment and injection rate under different operating conditions.

[0127] S3.5. Use the Rist operating line module to analyze the blast furnace ironmaking process through the operating line unit, coke saving potential unit and furnace body efficiency unit, provide evaluation indicators and optimization directions, continuously iterate the data of each module, and dynamically adjust the injection range based on the boundary conditions of the operating window module and the evaluation optimization direction of the Rist operating line module until the constraints of stable operation and efficient production of the blast furnace are met, and determine the optimal injection range of shale gas injection in the vanadium-titanium magnetite blast furnace under different working conditions.

[0128] This embodiment describes in detail the energy and mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace constructed in this application. Through the coordinated work of various modules, the optimal injection amount can be accurately determined, which can effectively optimize the energy utilization of the blast furnace ironmaking process, reduce the consumption of traditional fuels such as coke and pulverized coal, improve the energy utilization rate of shale gas, stabilize the operating conditions of the blast furnace, reduce the impurity content of molten iron, and improve the quality of molten iron, providing technical support for energy conservation and emission reduction, cost reduction and efficiency improvement in blast furnace ironmaking, and promoting green and efficient development of the steel industry.

[0129] Based on Example 1, this example describes in detail the calculation process of the energy-mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace of the present application, as follows: Figure 6 As shown, the details are as follows;

[0130] Obtain and import initial data values; including raw material and fuel composition, such as the content of various elements in iron ore, the chemical composition of coke and coal powder; blast parameters, such as blast temperature, humidity, and oxygen enrichment rate; slag basicity, coke ratio, and coal ratio in the element distribution ratio; and molten iron and slag temperatures.

[0131] After completing the data import, set the shale gas composition and injection rate, set the replacement ratio of shale gas to coke and pulverized coal, and calculate the direct reduction degree of blast furnace iron based on the effective carbon and hydrogen content, blast temperature and humidity data of the hydrogen-rich gas;

[0132] Ore and flux consumption is calculated based on the iron balance principle, which is based on the law of conservation of matter, meaning the total amount of iron input to the blast furnace should equal the total amount of iron output. During this calculation, the material conservation algorithm is used to accurately determine the iron content and distribution rate in the raw fuel, as well as the expected target composition of the molten iron. By establishing an iron balance equation and undergoing complex calculations, the amount of iron ore required to meet molten iron production needs is determined. At the same time, flux consumption is calculated based on the slag alkalinity requirements and the gangue composition of the ore to ensure that the slag has good performance and meets the desulfurization and slag removal requirements during the blast furnace smelting process.

[0133] After determining the ore and flux consumption, calculate the slag and its composition. Based on the determined ore and flux consumption, consider their respective chemical compositions and chemical reactions during the blast furnace smelting process, and perform calculations based on the law of conservation of elements. For example, the calcium, magnesium, silicon, and aluminum elements in the ore will react with the flux during the smelting process to form the main components of the slag. By analyzing and calculating these chemical reactions, the contents of the main components in the slag, such as MgO, Al2O3, CaO, and SiO2, as well as the amount of slag generated, can be determined.

[0134] When calculating the composition of pig iron, the initial content of each element in the ore, flux, and other raw materials is determined. This is based on the results of the iron balance and the transformation patterns in the smelting reactions, combined with the principles of thermodynamics and kinetics. For example, carbon participates in multiple reactions in the blast furnace, some of which enters the pig iron and some of which generates gases such as carbon monoxide. Through in-depth research and calculation of these reactions, the composition of the main elements in the pig iron, such as Fe, C, Si, and Mn, can be determined.

[0135] By comprehensively considering the composition of pig iron and slag, as well as information on gas reactions and heat exchange involved in the smelting process, a gas balance-thermodynamic calculation model is established to determine the blast volume required to meet the smelting process requirements. The model takes into account factors such as the reaction between oxygen and fuel, the amount and composition of generated gases, etc., to ensure that the chemical reactions in the blast furnace proceed smoothly and maintain a stable smelting process.

[0136] After calculating the slag and pig iron composition and blast volume, the top gas composition and volume are calculated. This calculation is based on the blast volume and the composition of the injected shale gas, taking into account the generation and conversion of gases such as CO, CO₂, H₂, and CH₄, and employing the principles of gas reaction equilibrium and the law of conservation of matter.

[0137] During the blast furnace smelting process, the combustion of fuels such as coke, pulverized coal, and shale gas produces a large amount of gas. Simultaneously, the reduction reaction of the ore also consumes and generates gas. For example, carbon reacts with oxygen to produce carbon monoxide and carbon dioxide, and methane in shale gas undergoes cracking and conversion reactions at high temperatures. By analyzing these complex reactions and combining the amounts of each substance in the material balance, a gas reaction balance equation is established to solve for the composition of each component in the top gas.

[0138] When calculating the total amount of coal gas, the amounts of each gas component are added together and converted into the actual coal gas volume based on the ideal gas state equation, combined with the temperature and pressure conditions of the blast furnace top. This provides key data for subsequent heat balance calculations and optimization of blast furnace operations.

[0139] After completing the above material balance calculations, it is necessary to organize the calculated data on ore, flux, slag, pig iron, blast, top gas, etc., compile a material balance sheet, and classify and summarize them according to the type of substance, elemental composition, and quantitative relationship, so that the material flow situation in the entire blast furnace smelting process can be clearly seen.

[0140] The material balance sheet details the input quantities of various raw materials and fuels, including the mass and composition of iron ore, coke, pulverized coal, and flux; the output quantities and composition of molten iron and slag; the flow rate and composition of blast air; and the flow rate and composition of top gas. The material balance sheet clearly shows the distribution and movement of each element within the blast furnace, facilitating the accuracy of calculations and providing intuitive data support for subsequent heat balance calculations and adjustments to blast furnace operations.

[0141] Heat balance calculation includes heat balance calculation of the whole furnace, heat balance calculation of high temperature zone, heat balance calculation of low temperature zone, theoretical combustion temperature calculation and furnace top gas temperature calculation;

[0142] Perform a full furnace heat balance calculation to obtain the chemical reaction heat of the raw fuel, the physical sensible heat of each substance, and the input and output values of the blast and injection energy in the blast furnace. Calculate the heat loss using the law of conservation of energy and compare the obtained heat loss with the set standard to determine whether the heat loss is constant. If not, adjust the blast parameters (such as blast temperature, humidity, and oxygen enrichment rate), injection parameters (such as shale gas injection volume and composition ratio), and raw fuel parameters (such as the calorific value and volatile matter content of coke and pulverized coal) based on the material data provided by the material balance module. Recalculate the heat input and output of each part according to the heat balance principle until the heat loss meets the constant requirement.

[0143] On the basis of constant heat loss, the theoretical combustion temperature of the high-temperature zone of the blast furnace is calculated in combination with the heat released by the fuel combustion reaction and the energy transfer and exchange in the area. According to the heat exchange mechanism of the low-temperature zone, the heat transfer between the gas and the material in the furnace and the energy distribution state are taken into consideration to calculate the top gas temperature. Through heat balance calculation, the energy distribution and utilization in the blast furnace are mastered.

[0144] This implementation describes in detail the construction of a comprehensive and accurate energy and mass balance calculation system for hydrogen-rich injection in blast furnaces. Through a strict calculation process, it achieves precise control of matter and energy in each link of blast furnace smelting, determines the optimal injection range, optimizes the fuel structure, and reduces solid fuel consumption; at the same time, it stabilizes the temperature field in the furnace, avoids abnormalities in the top gas temperature and theoretical combustion temperature, reduces equipment loss, improves production efficiency, promotes efficient and stable operation of blast furnaces, and promotes energy conservation, emission reduction and sustainable development in the steel industry.

[0145] Based on Example 1, this example describes in detail the effect of shale gas temperature on the operating window of the shale gas blast furnace energy quality model of this application, such as Figure 7-9 As shown, Figure 7 The hydrogen-rich gas temperature is 25°C and the blast temperature is 1100°C; Figure 8 The hydrogen-rich gas temperature is 25°C and the blast temperature is 1200°C; Figure 9 The hydrogen-rich gas temperature is 625°C and the blast temperature is 1100°C. The specific comparison is:

[0146] Figure 7 and Figure 8 The figure shows the operating window for shale gas replacement of coke at blast temperatures of 1100°C and 1200°C, respectively, while keeping other parameters constant (coal ratio: 108 kg / tHM, hydrogen-enriched gas temperature: 25°C). The figure shows that the shale gas operating window shifts downward and to the right with increasing blast temperature, while its shape and area do not change significantly. This indicates that, at the same injection rate, increasing blast temperature helps lower the upper and lower limits of oxygen enrichment, but has little effect on its adjustment range. As the blast temperature increases from 1100°C to 1200°C, the shale gas comprehensive operating window (RAFT range of 2000–2200°C) increases from 0–90 kg / tHM to 0–90.4 kg / tHM, respectively, and the oxygen enrichment corresponding to the maximum injection rate decreases from 14.2% to 12.9%. This indicates that increasing blast temperature slightly increases the injection range of the operating window but significantly reduces the corresponding oxygen enrichment range.

[0147] Figure 7 and Figure 9 It means that when the blast furnace is injected with hydrogen-rich gas, the heat income of the blast furnace is increased by preheating the hydrogen-rich gas, so as to reduce the coke ratio of the blast furnace. The operating window after coke replacement is calculated when the shale gas temperature is 25℃ and 600℃ (the blast temperature is constant at 1100℃ and the coal ratio is constant at 108kg / tHM). Figure 6 and Figure 8It can be seen that increasing the preheating temperature causes the operating window to shift downward and to the right. Under the same injection rate conditions, increasing the preheating temperature from 25°C to 600°C changes the shale gas comprehensive operating window injection rate range from 0-90 kg / tHM to 0-94 kg / tHM, and the oxygen enrichment rate corresponding to the maximum injection rate decreases from 14.2% to 13.7%. This shows that increasing the preheating temperature can significantly increase the injection range of the operating window, but has little effect on the oxygen enrichment rate range.

[0148] This implementation describes and compares the operating windows at different shale gas temperatures in detail, clearly demonstrating that increasing the shale gas preheating temperature can significantly increase the injection range of the operating window. Under the conditions of a constant blast temperature of 1100°C and a coal ratio of 108kg / tHM, when the shale gas temperature increases from 25°C to 600°C, the injection rate range of the comprehensive operating window expands from 0-90kg / tHM to 0-94kg / tHM, with little impact on the oxygen enrichment rate range. This means that flexible adjustments can be made within a wider injection rate range, providing greater room for optimizing blast furnace smelting operations.

[0149] The above are only preferred embodiments of the present invention, which do not limit the scope of protection of the present invention. For those skilled in the art, the present invention can be modified and varied in various ways. Any changes, modifications, replacements, integrations and parameter changes to these embodiments through conventional substitutions or that can achieve the same functions without departing from the principles and spirit of the present invention fall within the scope of protection of the present invention.

Claims

1. A method for determining the optimal injection range based on a shale gas blast furnace energy quality model, characterized in that: include: S1. Obtaining data to determine the optimal initial injection range for a shale gas vanadium titanium blast furnace; S2. Set the shale gas composition and injection rate, determine the replacement ratio of shale gas to coke and pulverized coal, and calculate the direct reduction degree of iron; S3. Construct an energy-mass balance model for hydrogen-rich injection in a vanadium-titanium magnetite blast furnace, establish a reasonable operating window, and determine the optimal injection range; S4. Verify the optimal injection range through the Rist operation line module in the energy and mass balance model of hydrogen-rich injection in vanadium-titanium magnetite blast furnace.

2. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 1, characterized in that: The energy and mass balance model of hydrogen-rich injection in the vanadium-titanium magnetite blast furnace in S3 includes a material balance module, a heat balance module, a substitution ratio module, an operation window module and a Rist operation line module; The material balance module calculates the balance of elements and components in molten iron, slag, blast air, hearth, and top gas, determines the material balance results, and provides material basis data for the heat balance module; The heat balance module calculates the heat balance data of the whole furnace, high temperature zone and low temperature zone based on the material balance results; The replacement ratio module combines material balance results and heat balance data to calculate the ratio of hydrogen-rich gas replacing coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, and feeds it back to the operation window module; The operation window module adjusts the corresponding relationship between oxygen enrichment and injection amount in the blast to ensure stable operation of the blast furnace under different conditions through a reasonable operation window, and provides the boundary conditions of the optimal injection range; The Rist operation line module verifies the optimal injection range by analyzing the blast furnace ironmaking process, and provides evaluation indicators and optimization directions for determining the optimal injection range; The energy-mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace determines the optimal injection range of shale gas in a vanadium-titanium magnetite blast furnace under different working conditions through the cooperation of modules.

3. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 2, characterized in that: The material balance module performs balance calculations on the elements and components in molten iron, slag, blast air, hearth, and top gas to determine the material balance results, specifically including the following steps: S3.1.

1. Calculate the ore and flux consumption based on the iron balance principle, taking into account the iron content and distribution ratio in the raw materials and the expected target composition of the molten iron, and using the material conservation algorithm. S3.1.

2. Based on the determined ore and flux consumption, taking into account their respective chemical compositions and chemical reactions during the blast furnace smelting process, and according to the law of conservation of elements, calculate the slag production and determine the contents of the main components of the slag, namely MgO, Al2O3, CaO, and SiO2; S3.1.

3. Obtain the initial content of each element in the ore, flux, and other raw materials. Based on the iron balance results and the transformation laws in the smelting reaction, combined with the principles of thermodynamics and kinetics, calculate the composition of Fe, C, Si, and Mn elements in the pig iron; S3.1.

4. Consider the composition of pig iron, slag, and the gas reactions and heat exchange information involved in the smelting process, and establish a gas balance-thermodynamic calculation model to determine the blast volume required to meet the smelting process requirements; S3.1.

5. Calculate the corresponding direct reduction degree based on the blast volume and the composition of the injected shale gas. Considering the generation and conversion of CO, CO2, H2, and CH4 gases, and using the principles of gas reaction equilibrium and the law of conservation of matter, calculate the composition of each component in the top gas and the total amount of gas. S3.1.

6. The calculated data on ore, flux, slag, pig iron, blast air, and top gas shall be classified, summarized, and organized according to the type of substance, elemental composition, and quantitative relationship, and a material balance sheet shall be prepared.

4. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 2, characterized in that: The calculation process of the heat balance module is as follows: S3.2.

1. Obtain the chemical reaction heat of the raw materials and fuels, the physical sensible heat of each substance, the input and output values of the blast and injection energies in the blast furnace, perform a heat balance calculation for the entire furnace, and obtain the heat loss; S3.2.

2. Compare the heat loss obtained with the set standard to determine whether the heat loss is constant. If not, adjust the parameters and recalculate until the heat loss meets the constant requirement. S3.2.

3. Calculate the theoretical combustion temperature for the high-temperature zone of the blast furnace, assuming constant heat loss, taking into account the heat released by the fuel combustion reaction and the energy transfer and exchange within the zone; S3.2.

4. Calculate the furnace top gas temperature based on the heat exchange mechanism in the low-temperature zone, taking into account the heat transfer between the furnace gas and the material and the energy distribution state; S3.2.

5. Determine the reasonable theoretical combustion temperature and top gas temperature range based on the original raw material and fuel conditions of the blast furnace. Determine the original blast oxygen enrichment conditions of the charge based on the theoretical combustion temperature and top gas temperature calculated previously, and establish a mathematical model for the corresponding operation window.

5. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 2, characterized in that: If the parameters in S3.2.2 are not constant, the parameters are adjusted and recalculated. The parameters include blast parameters, injection parameters and raw fuel parameters, which are adjusted according to the material data provided by the material balance module; the blast parameters are adjusted to include blast temperature, humidity, and oxygen enrichment rate; the injection parameters are adjusted to include shale gas injection range and component ratio; the raw fuel parameters are adjusted to include the calorific value and volatile matter content of coke and coal powder, and the heat input and output of each part are recalculated according to the heat balance until the heat loss reaches a constant state.

6. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 2, characterized in that: The replacement ratio module includes a direct reduction unit, a hydrogen-rich gas replacement coke unit, and a hydrogen-rich gas replacement coal powder unit; The direct reduction degree unit calculates the direct reduction degree of blast furnace iron based on the reaction path and distribution of iron elements in the blast furnace, combined with the element content of each substance in the material balance and the influence of heat reaction in the heat balance; The hydrogen-rich gas replacement coke unit calculates the ratio of hydrogen-rich gas to coke by analyzing the chemical reactions between hydrogen-rich gas and coke in the blast furnace, their ability to provide heat and reducing gas, and combining the material input determined by the material balance results and the heat demand reflected by the heat balance data. The hydrogen-rich gas replacement pulverized coal unit calculates the ratio of hydrogen-rich gas to pulverized coal based on the reaction characteristics and energy contribution of hydrogen-rich gas and pulverized coal in the furnace, combined with material balance and heat balance data; By feeding back the calculated ratio of hydrogen-rich gas replacing coke and pulverized coal and the direct reduction degree of blast furnace iron to the operation window module, key data are provided for determining a reasonable operation window.

7. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 6, characterized in that: The operation window module includes a raceway theoretical combustion temperature unit and a furnace top gas temperature unit; The raceway theoretical combustion temperature unit simulates the fuel combustion process in the raceway based on the heat data provided by the heat balance module, the material input information of the material balance module, and the reaction parameters of the substitution ratio module, calculates the theoretical combustion temperature, and obtains the feasible range of blast oxygen enrichment and injection rate under the theoretical combustion temperature; The top gas temperature unit calculates the top gas temperature based on the heat exchange conditions of the entire furnace, gas composition and flow data, and evaluates the thermal status of the upper part of the blast furnace and the gas energy utilization rate; The reasonable operation window is comprehensively determined by the theoretical combustion temperature unit of the raceway zone and the furnace top gas temperature unit. Based on the temperature boundaries under different working conditions, the correspondence between oxygen enrichment and injection amount in the blast is dynamically adjusted to provide boundary conditions for determining the optimal injection range.

8. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 7, characterized in that: The reaction parameters of the substitution ratio module include the content of each substance element in the material balance, the reaction heat of the reaction in the substitution ratio module, the amount and proportion of the substance participating in the reaction, and the reaction rate data; each substance includes ore, fuel, and blast; ore includes compounds corresponding to iron, calcium, and silicon elements; fuel includes substances corresponding to carbon and hydrogen elements; and blast includes oxygen and nitrogen.

9. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claim 2, characterized in that: The Rist operating line module includes an operating line unit, a coke saving potential unit and a furnace efficiency unit; The operating line unit is based on material balance and heat balance, combined with the chemical reaction and transmission process of various substances in the blast furnace, to intuitively display the progress and status of the redox reaction in the blast furnace; The coke saving potential unit analyzes the potential space for reducing coke consumption by improving the reaction path and energy utilization under hydrogen-rich injection conditions based on the results of the operating line unit; The furnace efficiency unit evaluates the effectiveness of heat transfer and reduction reaction in the furnace; The operating line unit identifies the key nodes and states of the reaction in the blast furnace, the coke saving potential unit points out the direction of reducing coke usage, and the furnace body efficiency unit reflects the working performance of the furnace body. Through comprehensive analysis of the blast furnace ironmaking process, it provides the degree of coke saving, reaction efficiency evaluation indicators, and optimization directions for adjusting the injection range and optimizing operating parameters to determine the most suitable injection amount.

10. The method for determining the optimal injection range based on the shale gas blast furnace energy quality model according to claims 1-9, characterized in that: The optimal injection range is determined by the energy-mass balance model of hydrogen-rich injection in a vanadium-titanium magnetite blast furnace, specifically including: S3.

1. Calculate the element and component data of molten iron, slag, blast air, hearth, and top gas through the material balance module to form the material basis. S3.

2. Use the heat balance module to calculate the heat balance data of the entire furnace, high temperature zone, and low temperature zone to provide energy data support for other modules; S3.

3. The replacement ratio module uses data from the material balance module and the heat balance module to calculate the ratio of hydrogen-rich gas replacement of coke and pulverized coal, as well as the direct reduction degree of blast furnace iron, through the direct reduction degree unit, the hydrogen-rich gas replacement of coke unit, and the hydrogen-rich gas replacement of pulverized coal unit. This calculation is then fed back to the operation window module. S3.

4. The operation window module uses the raceway theoretical combustion temperature unit and the furnace top gas temperature unit, combined with data from the material balance module, heat balance module, and displacement ratio module, to determine the feasible range and boundary conditions for blast oxygen enrichment and injection rate under different operating conditions. S3.

5. Use the Rist operating line module to analyze the blast furnace ironmaking process through the operating line unit, coke saving potential unit and furnace body efficiency unit, provide evaluation indicators and optimization directions, iterate the data of each module, and dynamically adjust the injection range based on the boundary conditions of the operating window module and the evaluation optimization direction of the Rist operating line module until the constraints of stable operation and efficient production of the blast furnace are met, and determine the optimal injection range of shale gas injection in the vanadium-titanium magnetite blast furnace under different working conditions.

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