Blast furnace off-line and on-line material distribution simulation method

Abstract

The invention relates to a blast furnace off-line and on-line material distribution simulation method, which belongs to a blast furnace material distribution simulation method, and comprises the following steps of: acquiring basic data, namely acquiring crude fuel quality data, under-tank material discharge data, a material distribution matrix, a stock rod, a material distribution signal and chute tilting data; an online material distribution model algorithm is divided into three parts, namely a material flow falling point, a material surface shape and material surface downward movement, and the material flow falling point analyzes the stress and movement law of a single furnace charge particle according to a single particle stress analysis method; according to a normal distribution method, the furnace throat is radially and equidistantly divided according to the charge level shape by using an infinitesimal thought, and iterative calculation is carried out by adopting a volume equality principle; according to the charge level downward moving method, calculation is conducted according to the principle that a furnace throat vertically moves downwards and a furnace body radiates downwards; and model algorithm correction: comparing a simulation result with an actual result, comprehensively considering an actual loading process, and correcting and perfecting the model algorithm in a later period.

Description

Technical Field

[0001] The invention relates to a simulation method for blast furnace burden distribution. Background Art

[0002] Intelligent manufacturing technology has become an objective trend in the development of the world's manufacturing industry, and the blast furnace charge distribution system is the core link of the blast furnace smelting process. How to quantitatively analyze the rationality of the charge distribution system, and how to reasonably optimize and adjust the charge distribution system according to changes in furnace conditions during the production process as raw material quality, batch size, blast furnace charge structure, coke load, air volume, etc. change. It is urgent to use the Internet of Things technology and intelligent systems to implement blast furnace charge distribution control technology to reduce production costs, improve production efficiency, and reduce furnace condition fluctuations.

[0003] At present, there are disclosed methods for blast furnace charge distribution control, for example: Patent Publication No. CN113656966A discloses an online charge distribution model simulation method for a blast furnace bell-free top, the main steps of which are to calculate the material flow trajectory, material flow width, charge stacking angle in the furnace, coke slippage, etc., and then simulate the shape of the blast furnace charge surface after charge distribution based on the model calculation results and the initial charge surface shape of the blast furnace. However, the influence of the mixed layer of the charge surface is not considered, and the state information of the charge surface after charge distribution on the top cannot be accurately calculated.

[0004] Therefore, it is necessary to propose a method that fully considers the influence of changing factors such as the stacking angle of the charge in the furnace and the mixed layer of the charge surface, can calculate the landing point information at any charge distribution angle, the charge surface shape and radial ore-coke ratio distribution under any charge distribution matrix, and intuitively display the blast furnace charge surface shape parameters, etc., so as to facilitate technicians to accurately control the airflow through changes in the radial coke load distribution, which is of great significance for achieving low-carbon smelting in the blast furnace. Summary of the invention

[0005] The purpose of the present invention is to propose an accurate and practical method for calculating / simulating the material surface after blast furnace top distribution. Offline and online simulation calculations are performed on the material flow trajectory, internal material surface shape, and material surface downward movement process of blast furnace top distribution. The landing point position information under any distribution angle, the material surface shape under any distribution matrix, and the radial ore-coke ratio distribution can be calculated. The airflow is precisely controlled by the change of radial coke load distribution to achieve low-carbon smelting in the blast furnace.

[0006] The technical solution adopted by the present invention to solve the above problems is: a blast furnace off-line and on-line material distribution simulation method, comprising the following steps:

[0007] Step 1: Basic data collection: including raw material quality data (in the MES system), under-tank material discharge data, material distribution matrix, probe, material distribution signal, chute tilting (in the PLC control system) and other data, which are collected through OPC and DBLink, and stored in the Oracle database according to the principle of "classification and table, high frequency short-term, low frequency long-term" (high-frequency data is stored for a short period, low-frequency data is stored for a long period), which ensures data application needs while improving storage capacity and query efficiency.

[0008] Step 2. Model algorithm design: The online distribution model algorithm is divided into three parts: material flow landing point, material surface shape, and material surface downward movement. Among them: a. The material flow landing point is based on the single-particle force analysis method to analyze the force and movement law of a single charge particle from the material tank-center throat-chute-empty area-material surface; b. The material surface shape is based on the normal distribution method, using the microelement idea to divide the furnace throat radially into equal intervals, and the volume equality principle (the actual volume loaded is the same as the volume piled up in this simulation) is used for iterative calculation; c. The material surface downward movement method uses the principle of "vertical downward movement of the furnace throat and radial downward movement of the furnace body" for calculation.

[0009] Step 3: Model algorithm correction: By comparing the simulation results with the actual results and taking into account the actual loading process, the model algorithm was corrected and improved in the following aspects: a. Material tank form, parallel tanks or series tanks; b. Chute shape: square and round; c. Chute tilting: considering the inter-gear materials with large adjacent angle differences in the distribution matrix.

[0010] Step 4: Software development: This model software development adopts CS architecture and uses .NET language for development, including server, client, Socekt communication service, etc.

[0011] Step 5. Functional design: including dynamic simulation of blast furnace charging process, material surface shape, material surface downward movement process, real-time calculation and analysis of radial ore-coke layer thickness and ore-coke ratio distribution corresponding to the distribution matrix, providing quantitative basis for blast furnace operators to adjust the distribution system.

[0012] According to the technical solution of step 3, the internal and external stack angles of the charge are corrected and calculated, where the internal stack angle β in Refers to the angle between the inclined plane formed by the charge close to the center line of the blast furnace and the horizontal plane; the outer pile angle β out Refers to the angle between the inclined plane formed by the charge close to the blast furnace wall and the horizontal plane. The inner and outer pile angles are mainly affected by the height of the charge line and the radius of the landing point. The deeper the charge line is, the greater the impact of the charge on the charge surface is, and the smaller the pile angle is; the closer the landing point is to the furnace wall, the greater the support effect of the furnace wall on the charge is, and the smaller the outer pile angle is.

[0013] β in and β out The calculation formula is as follows:

[0014]

[0015] In the formula

[0016] a i , a0——the maximum value of the internal stack angle of the blast furnace;

[0017] b i , b0——the influence factor of material line on the stacking angle,

[0018]

[0019] c i , c0——the influence factor of the landing point on the heap angle,

[0020]

[0021] r——radius of the charge landing point, m;

[0022] R 喉 ——Blast furnace throat radius, m.

[0023] According to the technical solution of step 3, the influence of the mixed layer on the material surface is fully considered. The main factors affecting the formation of the mixed layer include the particle diameter of different batches of furnace materials, bulk density and material line height. The greater the difference in particle diameter of the furnace materials entering the furnace, the stronger the mixed layer; the greater the difference in bulk density of the furnace materials entering the furnace, the stronger the mixed layer; the deeper the material line, the stronger the mixed layer. The calculation formula of the mixed layer △l is as follows:

[0024]

[0025] In the formula

[0026] l——material layer thickness, unit: m;

[0027] n 布 - number of fabric loops;

[0028] r x ——Distance from the landing point, unit: m;

[0029] r——radius of the landing point, unit: m;

[0030] a, b——material surface shape coefficients, unit: m.

[0031] After the above scheme is implemented, the "offline + online" charging of the blast furnace can be calculated, the shape of the charging surface can be simulated offline, the distribution of the ore-coke ratio can be obtained, and an exploratory attempt can be made on the effect of the charging system; the establishment of the online model is based on the single-grain force analysis and collision theory, and comprehensively considers factors such as the physical properties of the charge, the type of charge tank, the shape of the chute, the sliding of the charge, the adhesion of the gas flow, etc., and analyzes the movement state of the charge from the charge tank->throat->chute->charge surface. The flow trajectory of the charging on the blast furnace top, the shape of the internal charge surface, and the downward movement of the charge surface are simulated online to achieve online simulation of the blast furnace charge surface shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the inner and outer angles of the charge in the blast furnace charge distribution simulation method in the embodiment;

[0033] Figure 2 This is a diagram of the material surface display interface of a blast furnace in the embodiment, which uses software to implement blast furnace online material distribution calculation according to this method. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with the embodiments shown in the accompanying drawings. The embodiments are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0035] As shown in the figure, a blast furnace "offline + online" material distribution simulation method in this embodiment includes the following steps:

[0036] Step 1: Basic data collection: including raw material quality data (in the MES system), under-tank material discharge data, material distribution matrix, probe, material distribution signal, chute tilting (in the PLC control system) and other data, which are collected through OPC and DBLink, and stored in the Oracle database according to the principle of "classification and table, high frequency short-term, low frequency long-term" (high-frequency data is stored for a short period, low-frequency data is stored for a long period), which ensures data application needs while improving storage capacity and query efficiency.

[0037] Step 2. Model algorithm design: The online distribution model algorithm is divided into three parts: material flow landing point, material surface shape, and material surface downward movement. Among them: a. The material flow landing point is based on the single particle force analysis method to analyze the force and movement law of a single charge particle from the material tank-center throat-chute-empty area-material surface; b. The material surface shape is based on the normal distribution method, using the microelement idea to divide the furnace throat radially into equal intervals, and the volume equality principle (the actual volume loaded is the same as the volume piled up in this simulation) is used for iterative calculation; c. The material surface downward movement method uses the principle of "vertical downward movement of the furnace throat and radial downward movement of the furnace body" for calculation.

[0038] Step 3: Model algorithm correction: By comparing the simulation results with the actual results and taking into account the actual charging process, the model algorithm was corrected and improved in the following aspects: a. Material tank form, parallel tanks or series tanks; b. Chute shape: square and round; c. Chute tilting; d. Internal and external stacking angles of furnace charge; e. Influence of mixed material layer. Interlayer materials with large angle differences between adjacent layers in the distribution matrix were considered.

[0039] The calculation of the correction of the inner and outer pile angles of the charge is as follows: Inner pile angle β in Refers to the angle between the inclined plane formed by the charge close to the center line of the blast furnace and the horizontal plane; the outer pile angle β out Refers to the angle between the inclined plane formed by the charge close to the blast furnace wall and the horizontal plane. The inner and outer pile angles are mainly affected by the height of the charge line and the radius of the landing point. The deeper the charge line is, the greater the impact of the charge on the charge surface is, and the smaller the pile angle is; the closer the landing point is to the furnace wall, the greater the support effect of the furnace wall on the charge is, and the smaller the outer pile angle is.

[0040] β in and β out The calculation formula is as follows:

[0041]

[0042] In the formula

[0043] a i , a0——the maximum value of the internal stack angle of the blast furnace;

[0044] b i , b0——the influence factor of material line on the stacking angle,

[0045]

[0046] c i , c0——the influence factor of the landing point on the heap angle,

[0047]

[0048] r——radius of the charge landing point, m;

[0049] R 喉 ——Blast furnace throat radius, m.

[0050] The mixed material layer is calculated as follows: The main factors affecting the formation of the mixed layer include the particle diameter of different batches of furnace materials, bulk density and material line height. The greater the difference in particle diameter of the furnace materials entering the furnace, the stronger the mixed layer; the greater the difference in bulk density of the furnace materials entering the furnace, the stronger the mixed layer; the deeper the material line, the stronger the mixed layer. The calculation formula for the mixed material layer is as follows:

[0051]

[0052] In the formula

[0053] l——material layer thickness, unit: m;

[0054] n 布 - number of fabric loops;

[0055] r x ——Distance from the landing point, unit: m;

[0056] r——radius of the landing point, unit: m;

[0057] a, b——material surface shape coefficients, unit: m.

[0058] Step 4: Software development: This model software development adopts CS architecture and uses .NET language for development, including server, client, Socekt communication service, etc.

[0059] Step 5. Functional design: including dynamic simulation of blast furnace charging process, material surface shape, material surface downward movement process, real-time calculation and analysis of radial ore-coke layer thickness and ore-coke ratio distribution corresponding to the distribution matrix, providing quantitative basis for blast furnace operators to adjust the distribution system.

[0060] After the above scheme is implemented, the "offline + online" charging of the blast furnace can be calculated, the shape of the charging surface can be simulated offline, the distribution of the ore-coke ratio can be obtained, and an exploratory attempt can be made on the effect of the charging system; the establishment of the online model is based on the single-grain force analysis and collision theory, and comprehensively considers factors such as the physical properties of the charge, the type of charge tank, the shape of the chute, the sliding of the charge, the adhesion of the gas flow, etc., and analyzes the movement state of the charge from the charge tank->throat->chute->charge surface. The flow trajectory of the charging on the blast furnace top, the shape of the internal charge surface, and the downward movement of the charge surface are simulated online to achieve online simulation of the blast furnace charge surface shape.

[0061] In addition to the above embodiments, the present invention also includes other implementation modes. Any technical solutions formed by equivalent transformation or equivalent replacement should fall within the protection scope of the claims of the present invention.

Claims

1. A blast furnace off-line and on-line material distribution simulation method, characterized in that: include: Step 1: Basic data collection: including raw fuel quality data, under-tank material discharge data, material distribution matrix, probe, material distribution signal, and chute tilting data, which are collected through OPC and DBLink; Step 2: Model algorithm design: The online distribution model algorithm is divided into three parts: material flow landing point, material surface shape, and material surface downward movement. Among them: a. The material flow landing point is based on the single particle force analysis method to analyze the force and movement law of a single charge particle from the material tank-central throat-chute-empty area-material surface; b. The material surface shape is based on the normal distribution method, using the microelement idea to divide the furnace throat radially into equal intervals, and the equal volume principle is adopted: the actual volume loaded is the same as the volume piled up in this simulation for iterative calculation; c. The material surface downward movement method uses the principle of vertical downward movement of the furnace throat and radial downward movement of the furnace body for calculation; Step 3: Model algorithm correction: By comparing the simulation results with the actual results and taking the actual loading process into consideration, the model algorithm is corrected and improved in the following aspects: a. Material tank form, parallel tanks or series tanks; b. Chute shape: square and round; c. Chute tilting: Consider the adjacent large angle difference between the interlayer materials in the material distribution matrix.

2. The method according to claim 1, characterized in that: Step 1: For data collection, it is stored in the Oracle database according to the principle of "classification and table division, high frequency short-term, low frequency long-term", with high-frequency data stored for a short period and low-frequency data stored for a long period.

3. The method according to claim 1, characterized in that: Step 3: Correct the internal and external stack angles of the charge, where the internal stack angle β in Refers to the angle between the inclined plane formed by the charge close to the center line of the blast furnace and the horizontal plane; the outer pile angle β out Refers to the angle between the inclined plane formed by the charge close to the blast furnace wall and the horizontal plane, β in and β out The calculation formula is as follows: In the formula a i , a0——the maximum value of the internal stack angle of the blast furnace; b i , b0——the influence factor of material line on the stacking angle; c i , c0——the influence factor of the landing point on the pile angle; r——radius of the charge landing point, m; R 喉 ——Blast furnace throat radius, m.

4. The method according to claim 1, characterized in that: Step 3: Considering the influence of the mixed layer on the material surface, the calculation formula for the mixed layer thickness △l is as follows: In the formula l——material layer thickness, unit: m; n 布 ——Number of fabric loops; rx——the distance from the landing point, unit: m; r——radius of the landing point, unit: m; a, b——material surface shape coefficients, unit: m.

5. The method according to claim 1, characterized in that: Also includes: Step 4: Software development: Adopt CS architecture and use .NET language for development, including server, client, and Socekt communication service; Step 5. Functional design: including dynamic simulation of blast furnace charging process, material surface shape, material surface downward movement process, real-time calculation and analysis of radial ore-coke layer thickness and ore-coke ratio distribution corresponding to the distribution matrix, providing quantitative basis for blast furnace operators to adjust the distribution system.

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