Coke evaluation method taking microscopic parameters as core

Abstract

The invention discloses a coke evaluation method taking microcosmic parameters as a core. The coke evaluation method comprises the following steps: detecting metallurgical coke quality performance detection indexes including moisture, ash content, volatile components and sulfur content; the crushing strength and the abrasive resistance are high; macroscopic indexes of thermal reactivity and post-thermal-reaction strength are divided into three dimensions, and metallurgical coke performance is evaluated macroscopically; analyzing a metallurgical coke pore structure; analyzing a metallurgical coke microcrystalline structure; a metallurgical coke pore structure and a microcrystalline structure are combined to carry out coke microcosmic performance research; analyzing economic and technical parameters of the blast furnace using the metallurgical coke; and constructing a three-dimensional metallurgical coke evaluation method which takes the macroscopic index as a basis, takes the microcosmic index as a core and takes the blast furnace smelting demand as a characteristic. The method effectively solves the problems that coke evaluation indexes cannot form a powerful guiding effect on production of the blast furnace, and some macroscopic indexes are good in performance in the application process of the coke evaluation indexes in the blast furnace, but the coke evaluation indexes cannot reflect good universality in the production process of the blast furnace.

Description

Technical Field

[0001] The present invention belongs to the technical field of detection, and particularly relates to a method for evaluating coke with microparameters as the core. Background Art

[0002] Metallurgical coke is the core raw material for steel production, a pillar industry of the national economy, and is irreplaceable, playing an important guarantee and supporting role in the development of the steel industry. Metallurgical coke is the heat source, reducing agent, burden column skeleton and penetrant in blast furnace smelting production, and is also the most important means for adjusting parameters in the blast furnace production process. In recent years, with the development and progress of blast furnace smelting technology, especially the rapid development of large-scale blast furnace volume, high blast temperature technology and oxygen-enriched coal injection technology, coke, as the skeleton of the burden column in the blast furnace, plays a more prominent role in ensuring air permeability and liquid permeability in the blast furnace. The important role of coke in the blast furnace is self-evident. There are many evaluation indexes for the quality performance of coke, including basic indexes such as moisture, ash, volatile matter, sulfur content, mechanical strength, etc., and thermal performance indexes (thermal reactivity and strength after reaction) that better simulate the state in the blast furnace. These quality indexes of macroscopic properties can reflect the quality performance of metallurgical coke to a certain extent. As a carbon matrix porous brittle material, especially in the application process in the blast furnace, although some macroscopic index performances are good, the actual performance in the blast furnace production is not good. That is to say, the evaluation indexes of coke cannot strongly guide the blast furnace production. In other words, the matching between the evaluation of coke quality performance and blast furnace application is not strong. The complexity of the coke structure determines that it is one-sided to evaluate the smelting process of metallurgical coke in the blast furnace only by macroscopic performance indexes, and it is also difficult to explain the production phenomena in the blast furnace and the differences in coke quality. There is a need for a method to evaluate the performance of metallurgical coke from a microscopic perspective to reasonably explain the production phenomena in the blast furnace. Summary of the Invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to provide a method for evaluating coke with microparameters as the core.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A method for evaluating coke with microparameters as the core according to the present invention includes the following steps:

[0006] Step 1: Divide the metallurgical coke quality performance detection indexes, including moisture, ash, volatile matter, sulfur content; shatter strength, abrasion strength; thermal reactivity, strength after thermal reaction, into three dimensions to evaluate the performance of metallurgical coke macroscopically;

[0007] Step 2: Analyze the pore structure of metallurgical coke;

[0008] The pore structure of metallurgical coke is analyzed by microscope analysis and scanning electron microscope (SEM) analysis respectively;

[0009] Step 3: Analyze the microcrystalline structure of metallurgical coke;

[0010] The microcrystalline structure of metallurgical coke is generally detected by XRD;

[0011] The main technical parameters of the microcrystalline structure of metallurgical coke include the peak width of the XRD pattern, the peak height of the XRD pattern, and the stacking height of the lamellae;

[0012] Step 4: Carry out research on the microscopic properties of coke by combining the pore structure and microcrystalline structure of metallurgical coke;

[0013] Step 5: Analyze the economic and technical parameters of the blast furnace using metallurgical coke;

[0014] The analysis of the economic and technical parameters of the blast furnace should be based on the stable state of the blast furnace;

[0015] The blast furnace volumes and burden structures for comparative analysis of the economic and technical parameters of the blast furnace should be basically the same;

[0016] Step 6: Construct a three-dimensional evaluation method for metallurgical coke based on macroscopic indicators, with microscopic indicators as the core and blast furnace smelting requirements as the characteristics.

[0017] Furthermore, the moisture detection of coke is carried out in accordance with the national standard GB / T2001; the ash detection of coke is carried out in accordance with the national standard GB / T2001.

[0018] Furthermore, the volatile matter detection of coke is carried out in accordance with the national standard GB / T2001; the sulfur content detection of coke is carried out in accordance with the national standard GB / T2001.

[0019] Furthermore, the shatter strength detection of coke is carried out in accordance with the national standard GB / T2006; the abrasion resistance strength detection of coke is carried out in accordance with the national standard GB / T2006.

[0020] Furthermore, the reactivity with carbon dioxide of coke is detected in accordance with the national standard GB / T4000; the strength after reaction with carbon dioxide of coke is detected in accordance with the national standard GB / T4000.

[0021] Furthermore, the pore structure of metallurgical coke includes but is not limited to parameters such as porosity, pore wall thickness, and pore diameter.

[0022] Furthermore, the economic and technical parameters determined by the blast furnace include at least but are not limited to parameters such as the blast furnace utilization coefficient, fuel ratio, and blast furnace stable production cycle technical parameters.

[0023] Compared with the prior art, the beneficial technical effects of the present invention:

[0024] The present invention effectively solves the problem that the indexes for coke evaluation cannot strongly guide the production of blast furnaces. Especially during the application process in blast furnaces, there is a common problem that some macro indexes have good performance, but the performance is not good during the production process of blast furnaces. A three-dimensional metallurgical coke evaluation method based on macro indexes, with micro indexes as the core and the characteristics of blast furnace smelting requirements, is constructed. It is of great significance and practical value for scientifically and objectively evaluating the quality of metallurgical coke, especially the behavior changes of metallurgical coke during blast furnace smelting, improving the role of metallurgical coke in blast furnaces, reducing the fuel ratio, and increasing the utilization coefficient of blast furnaces. At the same time, it also has guiding significance for optimizing the coking coal blending structure, expanding new coking coal sources, and reducing the cost of coking coal blending. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an analysis diagram of the pore structure of coke for a 7-meter top-charging coke oven;

[0026] Figure 2 It is an analysis diagram of the pore structure of coke for a 6-meter top-charging coke oven. DETAILED DESCRIPTION OF THE INVENTION

[0027] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention will be further described in detail below in conjunction with the specific embodiments.

[0028] A coke evaluation method with micro parameters as the core according to the present invention, the core principle of the method is: based on macro indexes, three-dimensional division of macro indexes; with micro indexes as the core, using pore structure and microcrystalline structure characterization means to construct a three-dimensional metallurgical coke evaluation method based on the properties of the coke body and characterized by the requirements of blast furnace smelting.

[0029] Theoretical basis 1 of the method: During the blast furnace smelting process, from the perspective of transport theory, its essence is a heat transfer, mass transfer, and phase change process of reverse contact of material flow and energy flow in a specific shaft furnace. This process is interlaced, interdependent, and sometimes contradictory. Blast furnace smelting is dynamic, non-equilibrium, and always in a state of change. Any change in the energy flow and material flow will affect the process.

[0030] Theoretical basis 2 of the method: Metallurgical coke is the most basic, important, and largest-consuming basic material in blast furnace production, and its quality is the key to improving the utilization coefficient of blast furnaces.

[0031] Theoretical basis 3 of the method: The test design idea of coke reactivity (CRI) and post-reaction strength (CSR) simulates the carbon melting reaction of coke in blast furnaces, which is a big step forward compared to M40 and M10. However, its simulation is still not ideal during the operation of blast furnaces, and there are problems such as alkali-free conditions, reaction temperature, and CO2 concentration.

[0032] Theoretical Basis 4: Metallurgical coke is a cracked, massive, heterogeneous, and brittle solid material composed of pores and pore walls. Coke thermal performance is primarily determined by the pore structure parameters of the coke itself. Differences in volatile matter release and softening flow behavior lead to significant differences in the pore structure of coke formed from different coal ranks. Pores provide pathways for CO2 to enter the coke, significantly influencing the coke dissolution reaction.

[0033] Theoretical Basis 5: Coking coal is a mixture of various organic compounds and small amounts of inorganic minerals. The organic compounds are composed of high-molecular-weight organic polymers centered around an aromatic nucleus. Its basic structural unit is a polymerized aromatic nucleus with peripheral side chains. During the coking process, the side chains on the aromatic nucleus of the coking coal continuously detach and decompose, while the aromatic nucleus condenses and condenses to form a microcrystalline structure. Therefore, the basic unit of the coke pore wall is a microcrystalline containing residual inorganic minerals from the coal.

[0034] The specific steps of this embodiment are as follows:

[0035] Step 1: divide the metallurgical coke quality performance test indicators such as moisture, ash, volatile matter, sulfur; crushing strength (M40), abrasion resistance (M10); thermal reactivity (CRI), and post-thermal reaction strength (CSR) into three dimensions to evaluate the metallurgical coke performance from a macro perspective;

[0036] Furthermore, the moisture content of coke is tested in accordance with the national standard GB / T2001;

[0037] Furthermore, the ash content of coke is tested in accordance with the national standard GB / T2001;

[0038] Furthermore, the coke volatile matter test is carried out in accordance with the national standard GB / T2001;

[0039] Furthermore, the sulfur content of coke is tested in accordance with the national standard GB / T2286;

[0040] Furthermore, the coke crushing strength (M40) test is carried out in accordance with the national standard GB / T2006;

[0041] Furthermore, the coke abrasion resistance (M10) test is carried out in accordance with the national standard GB / T2006;

[0042] Furthermore, the coke thermal reactivity (CRI) test is carried out in accordance with the national standard GB / T4000;

[0043] Furthermore, the coke strength after thermal reaction (CSR) test is carried out in accordance with the national standard GB / T4000;

[0044] Step 2: Analyze the pore structure of metallurgical coke

[0045] Furthermore, the pore structure of metallurgical coke is analyzed by microscopy and scanning electron microscopy (SEM) respectively;

[0046] Furthermore, the pore structure of metallurgical coke includes, but is not limited to, parameters such as porosity, pore wall thickness, and pore diameter;

[0047] Step 3: Analyze the microcrystalline structure of metallurgical coke;

[0048] Furthermore, the microcrystalline structure of metallurgical coke is generally detected by XRD;

[0049] Furthermore, the main technical parameters of the microcrystalline structure of metallurgical coke include the peak width of the XRD pattern, the peak height of the XRD pattern, and the stacking height of the lamellae;

[0050] Step 4: Conduct research on the microscopic properties of coke by combining the pore structure and microcrystalline structure of metallurgical coke;

[0051] Step 5: Analyze the economic and technical parameters of the blast furnace using metallurgical coke;

[0052] Furthermore, the analysis of the economic and technical parameters of the blast furnace should be based on the stable state of the blast furnace;

[0053] Furthermore, the blast furnace volumes and burden structures for comparative analysis of the economic and technical parameters of the blast furnace should be basically the same;

[0054] Furthermore, the determined economic and technical parameters of the blast furnace include at least, but are not limited to, technical parameters such as the blast furnace utilization coefficient, fuel ratio, and stable production cycle of the blast furnace;

[0055] Step 6: Construct a three-dimensional evaluation method for metallurgical coke based on macroscopic indicators, with microscopic indicators as the core and blast furnace smelting requirements as the characteristics.

[0056] The present invention effectively solves the problem that the indicators for coke evaluation cannot strongly guide the production of blast furnaces. Especially during the application process in blast furnaces, although some macroscopic indicator performances are good, the actual performance during blast furnace production is not satisfactory. A three-dimensional evaluation method for metallurgical coke based on macroscopic indicators, with microscopic indicators as the core and blast furnace smelting requirements as the characteristics, is constructed. It is of great significance and practical value for scientifically and objectively evaluating the quality of metallurgical coke, especially for understanding the behavior changes of metallurgical coke during blast furnace smelting, enhancing the role of metallurgical coke in blast furnaces, reducing the fuel ratio, and increasing the blast furnace utilization coefficient. At the same time, it also has guiding significance for optimizing the coking coal blending structure, exploring new coking coal sources, and reducing the cost of coking coal blending.

[0057] Using the self-produced metallurgical coke of a certain iron and steel enterprise to supply a 3000 m 3 blast furnace, the evaluation of metallurgical coke is carried out according to the patent method.

[0058] The macroscopic indexes for detecting the quality and performance of metallurgical coke, such as moisture, ash content, volatile matter, sulfur content; shatter strength (M40), abrasion resistance (M10); reactivity (CRI), strength after reaction (CSR), etc., are divided into three dimensions to evaluate the performance of metallurgical coke macroscopically. The specific test values are shown in Table 1.

[0059] Table 1 (%)

[0060]

[0061] The pore structure of metallurgical coke is analyzed by microscopy, as shown in Figure 1 and Figure 2 .

[0062] The pore structure of coke directly affects the carbon solution reaction, thus affecting the properties of coke. Coke is a porous brittle material, and its strength depends on the strength of the pore walls, cracks and pore structure characteristics. From the comprehensive analysis of two groups of typical coke pore diagrams, the pore analysis should achieve "four combinations within the diagram", that is, the four parameters of porosity, average pore diameter, average wall thickness and pore size distribution are combined and analyzed as a whole. From the analysis of the four parameter indexes, the coke from the 7-meter top-charging coke oven is significantly better than that from the 6-meter top-charging coke oven.

[0063] The microcrystalline structure of metallurgical coke is analyzed. The microcrystalline structure of metallurgical coke is generally detected by XRD, and the main technical parameters measured are the carbon layer diameter La, the layer stacking height Lc and the layer spacing d 002 These three parameters. The microcrystalline structure of the coke in the blast furnace at the tuyere area is analyzed to better study the changes in the microcrystalline structure of metallurgical coke after dissolution loss in the blast furnace. The values are shown in Table 2.

[0064] Table 2 Microcrystalline structure parameters of coke at different tuyeres

[0065]

[0066] The micro-performance research of coke is carried out by combining the pore structure and microcrystalline structure of metallurgical coke;

[0067] Under the stable state of the blast furnace, the economic and technical parameters of the blast furnace using metallurgical coke are analyzed. The economic and technical parameters determined by the blast furnace include at least but are not limited to technical parameters such as blast furnace utilization coefficient, fuel ratio, and stable production cycle of the blast furnace, as shown in Tables 3 - 6 respectively.

[0068] Table 3 Quality of sinter in the blast furnace (unit: %)

[0069] TFe FeO CaO <![CDATA[SiO2]]> F S MgO P R Drum Zn 56.67 9.27 10.48 5.08 0.11 0.0309 2.07 0.067 2.03 78.78 0.025

[0070] Table 4 Quality of pellet in the blast furnace (unit: %)

[0071] TFe FeO CaO <![CDATA[SiO2]]> F MgO S R Drum Swelling ratio Compressive strength 62.84 1.34 1.4 4.42 0.05 1.05 0.01 0.31 95.38 15.95 2008.2

[0072] Table 5 Blast Furnace Operating Parameters

[0073]

[0074] Table 6 Blast Furnace Technical Indicators

[0075] Output t Utilization coefficient Coke ratio kg / t Coke breeze ratio kg / t Fuel ratio kg / t Coal ratio kg / t 7063 2.354 327.3 36.4 534.7 171

[0076] Through the analysis of the economic and technical indicators of the blast furnace, the 3000m 3 blast furnace of this factory uses metallurgical coke, and the economic indicators of the blast furnace are good. Both the fuel ratio and the blast furnace utilization coefficient are at the forefront among blast furnaces of the same furnace type in the country.

[0077] Through the implementation of the above steps, a three-dimensional metallurgical coke evaluation method is constructed based on macroscopic indicators, with microscopic indicators as the core and the blast furnace smelting requirements as the characteristics.

[0078] The embodiments described above are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A coke evaluation method with microscopic parameters as the core, characterized in that: It includes the following steps: Step 1: Divide the metallurgical coke quality performance detection indicators, namely moisture, ash content, volatile matter, sulfur content, shatter strength, abrasion resistance, reactivity, and strength after reactivity, into three dimensions to evaluate the performance of metallurgical coke macroscopically; Step 2: Analyze the pore structure of metallurgical coke; The pore structure of metallurgical coke is analyzed by microscope analysis and scanning electron microscope (SEM) analysis respectively; Step 3: Analyze the microcrystalline structure of metallurgical coke; The microcrystalline structure of metallurgical coke is generally detected by XRD; The main technical parameters of the microcrystalline structure of metallurgical coke include the peak width of the XRD pattern, the peak height of the XRD pattern, and the stacking height of the lamellae; Step 4: Conduct research on the microscopic properties of coke by combining the pore structure and microcrystalline structure of metallurgical coke; Step 5: Analyze the economic and technical parameters of the blast furnace using metallurgical coke; The analysis of the economic and technical parameters of the blast furnace should be based on the stable state of the blast furnace; The blast furnace volumes and burden structures for comparative analysis of the economic and technical parameters of the blast furnace should be basically the same; Step 6: Construct a three-dimensional metallurgical coke evaluation method based on macroscopic indicators, with microscopic indicators as the core and blast furnace smelting requirements as the characteristics.

2. The coke evaluation method with microscopic parameters as the core according to claim 1, characterized in that: The detection of coke moisture is carried out in accordance with the national standard GB / T2001; the detection of coke ash content is carried out in accordance with the national standard GB / T2001.

3. The coke evaluation method with micro-parameters as the core according to claim 1, characterized in that: The detection of coke volatile matter is carried out in accordance with the national standard GB / T2001; the detection of coke sulfur content is carried out in accordance with the national standard GB / T2286.

4. The coke evaluation method with micro-parameters as the core according to claim 1, characterized in that: The detection of coke shatter strength is carried out in accordance with the national standard GB / T2006; the detection of coke abrasion resistance is carried out in accordance with the national standard GB / T2006.

5. The coke evaluation method with microscopic parameters as the core according to claim 1, characterized in that: The detection of coke reactivity is carried out in accordance with the national standard GB / T4000; the detection of coke strength after reactivity is carried out in accordance with the national standard GB / T4000.

6. The coke evaluation method with micro-parameters as the core according to claim 1, characterized in that: The pore structure of metallurgical coke includes, but is not limited to, parameters such as porosity, pore wall thickness, and pore diameter; 7. The coke evaluation method with microparameters as the core according to claim 1, characterized in that: The economic and technical parameters determined for the blast furnace include at least, but are not limited to, blast furnace utilization factor, fuel ratio, and technical parameters of the stable production cycle of the blast furnace.

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