Method for evaluating smelting performance of metallurgical coke by using powder coke rate

Abstract

The application discloses a kind of with powder coke rate determination metallurgical coke smelting performance evaluation method, comprising: comprehensive analysis and detection of test sample;To carry out detection analysis to the research coke of its to be analyzed research;After coke thermal reactivity is discharged from rotary drum, the original detection method is screened with 10mm sieve one screen increase is screened with 18mm, 15mm, 10mm, 8mm, 5mm, 3mm, 2mm, 1mm and 0.2mm nine level sieve respectively;The numerical value of each parameter is analyzed;The porosity of 3mm or more after reaction coke, pore wall and microstructure are detected respectively;Each parameter is analyzed;Comprehensive evaluation method system of coke smelting performance is formed.The application makes full use of conventional detection process and its innovative characterization new technical parameters, solves the technical problems of metallurgical coke melting process difficult to evaluate effectively, metallurgical coke in blast furnace "black box".

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of detection, and particularly relates to a method for evaluating the smelting performance of metallurgical coke by using a powder coke rate. BACKGROUND

[0002] Metallurgical coke is a core raw material for the production of the pillar industry of the national economy, i.e., the steel industry, and is irreplaceable, playing an important role in guaranteeing and supporting the development of the steel industry. Metallurgical coke is a heat source, a reducing agent, a column skeleton and a permeation agent for blast furnace smelting production, and is also the most important means for adjusting the process of blast furnace production. In recent years, with the development and progress of blast furnace smelting technology, especially the rapid development of large-scale blast furnaces, high blast temperature technology and blast oxygen-enriched coal injection technology, coke, as the skeleton of the column in the blast furnace, plays a more prominent role in ensuring the air and liquid permeation in the blast furnace. The quality of metallurgical coke has a great influence on the modern blast furnace smelting process, and becomes a key factor for limiting the stable, balanced, high-quality and efficient production of molten iron in the blast furnace.

[0003] The smelting performance of metallurgical coke is an important technical quality index of metallurgical coke, and is generally represented by reactivity (CRI) and post-reaction strength (CSR). However, the post-reaction strength (CSR) index is a single index under the condition of a specified temperature (1100 DEG C) and a specified reaction gas concentration, and can better represent the smelting performance of coke from one aspect. However, due to the complexity of coke and the complexity of the use process in the blast furnace, the smelting performance of metallurgical coke cannot be comprehensively evaluated. In addition, the detection process of coke reactivity and post-reaction strength is long, time-consuming and complicated, and therefore, many innovative detections are carried out after the detection. It is of great significance for further understanding the smelting performance of metallurgical coke and revealing the inherent quality of coke. At present, the coke detected after the reaction is only calculated according to the standard, and the percentage of coke greater than 10 mm in the post-reaction coke is taken as the detection index of post-reaction strength (CSR). There is no further processing and research of the sample in the detection process, which is not conducive to the in-depth study of coke, and is a missed opportunity for further studying the smelting performance of coke, especially the melting capacity. At the same time, it is also a waste of the detection process and resources. SUMMARY

[0004] In order to solve the above technical problems, the purpose of the present application is to provide a method for evaluating the smelting performance of metallurgical coke by using the post-reaction strength microstructure performance and the powder coke rate.

[0005] In order to solve the above technical problems, the present application adopts the following technical scheme:

[0006] In order to solve the above technical problems, the present application adopts the following technical scheme:

[0007] An evaluation method for determining the smelting performance of metallurgical coke by post-reaction strength microstructure performance and powder coke rate, the principles of the patent method are described as follows:

[0008] Principle 1: After the coke melting loss reaction, the internal microstructure and properties of the coke change profoundly, which is manifested as changes in index performance, and the smelting performance of the coke can be further explored through the changes in index performance;

[0009] Principle 2: The method of detecting the thermal performance of coke is currently a relatively direct method for detecting the smelting performance of metallurgical coke, which can effectively characterize its smelting performance, but the characterization parameters of the detection are relatively single, and other characterization parameters are defined through in-depth analysis and research of the detection process;

[0010] Principle 3: The melting loss reaction of coke in the blast furnace is the most core and key reaction process of the smelting performance of metallurgical coke, and is also the concentrated embodiment of the performance of coke.

[0011] The present application is an evaluation method for determining the smelting performance of metallurgical coke by powder coke rate, which specifically comprises the following steps:

[0012] Step 1: comprehensively analyze and detect the test sample, and focus on detecting parameters such as coke porosity, pore wall thickness, and coke microstructure;

[0013] Step 2: according to the national detection technical standard GB / T4000 "Detection method for reactivity and post-reaction strength of metallurgical coke", the research coke to be analyzed and researched is detected and analyzed;

[0014] Step 3: after the coke thermal reactivity is discharged from the rotary drum, the original detection method is increased to nine levels of 18mm, 15mm, 10mm, 8mm, 5mm, 3mm, 2mm, 1mm and 0.2mm screen sieving of the reaction product by adding a 10mm screen;

[0015] Step 4: analyze the numerical values of each characterization parameter in step 3;

[0016] Data analysis should be fully combined with principle 3, and the present application describes the melting capacity of coke in the blast furnace through new characterization parameters after the reaction, thereby providing new parameter support for blast furnace adaptability coke;

[0017] Step 5: detect the porosity, pore wall and microstructure of the coke with a particle size of 3mm or more after the reaction;

[0018] Step 6: analyze each parameter in step 5;

[0019] Step 7: construct a comprehensive evaluation method system for the smelting performance of coke.

[0020] Further, in step 3, the percentage content of each particle size is calculated after sieving by the nine levels of screens.

[0021] Further, in step 3, the powder coke rate is characterized by the percentage of the weight of ≤3mm to the weight after reaction.

[0022] Further, in step 3, the fine powder coke rate is characterized by the percentage of the weight of ≤1mm to the weight after reaction.

[0023] Further, in step 3, the columnar analysis graph and trend graph of each particle size sieve residue are drawn respectively.

[0024] Further, in step 6, the pore rate, pore wall and microstructure of the coke before reaction are analyzed and studied in combination with the parameters of step 5.

[0025] Compared with the prior art, the beneficial technical effects of the present application are:

[0026] The present application provides a technical solution for scientifically and effectively evaluating the smelting performance of metallurgical coke, which is a new technical parameter for innovative characterization in the process of fully utilizing conventional detection, solves the technical problems of difficult effective evaluation of metallurgical coke melting loss process and "black box" of metallurgical coke in blast furnace, and the application of the present application is a new evaluation system method for the use process of metallurgical coke, which can more scientifically understand metallurgical coke, especially the intuitive parameter characterization of the melting loss process of metallurgical coke in blast furnace, provides a system method for new understanding of metallurgical coke, provides a cognitive method for different volume blast furnace using quality differentiated coke, has important and practical significance for the stable operation and economic index improvement of blast furnace, and has good guiding significance for scientific coal blending, optimization of coal blending technology structure and reduction of coal blending coking cost, thereby generating huge economic benefits and good social benefits. DETAILED DESCRIPTION

[0027] In order to enable the personnel in the technical field to better understand the present application scheme, the present application will be further described in detail below in combination with specific embodiments.

[0028] The present application is an evaluation method for determining the smelting performance of metallurgical coke according to the strength microstructure performance and powder coke rate after reaction, and the principles of the patent method are described as follows:

[0029] Principle 1: The internal microstructure and properties of coke after coke melting loss reaction change deeply, which is manifested as changes in index performance, and the smelting performance of coke can be further explored through the changes in index performance.

[0030] Principle 2: The method of coke thermal performance detection is a relatively intuitive method for detecting the smelting performance of metallurgical coke, which can effectively characterize the smelting performance, but the characterization parameters of detection are relatively single, and other characterization parameters are defined through in-depth analysis and research on the detection process.

[0031] Principle 3, the melting loss reaction of coke in the blast furnace is the most core and key reaction process of the smelting performance of metallurgical coke, and is also the embodiment of the performance of coke.

[0032] An evaluation method for determining the smelting performance of metallurgical coke according to the post-reaction strength microstructure performance and the powder coke rate, the specific implementation steps are:

[0033] Step 1, comprehensively analyze and detect the test sample, and focus on detecting the coke porosity, pore wall thickness, coke microstructure and other parameters;

[0034] Step 2, according to the national detection technical standard GB / T4000 "Metallurgical coke reactivity and post-reaction strength detection method", the research coke to be analyzed and studied is detected and analyzed;

[0035] Step 3, after the hot reactivity of the coke is discharged from the drum, the original detection method is increased to one screening with 18mm, 15mm, 10mm, 8mm, 5mm, 3mm, 2mm, 1mm and 0.2mm nine levels of screen;

[0036] Further, after the nine-level screen screening, the percentage content of each particle size is calculated;

[0037] Further, the powder coke rate is characterized by the percentage of the weight of ≤3mm to the weight after reaction;

[0038] Further, the fine powder coke rate is characterized by the percentage of the weight of ≤1mm to the weight after reaction;

[0039] Further, the columnar analysis graph and the trend graph of each particle size screen are drawn respectively;

[0040] Step 4, analyze the numerical values of each characterization parameter in step 3;

[0041] Further, the data analysis should be fully combined with principle 3, and the present patent is to describe the melting capacity of coke in the blast furnace through the new characterization parameters after reaction, so as to provide new parameter support for the blast furnace adaptability coke;

[0042] Step 5, detect the porosity, pore wall and microstructure of the coke after reaction of more than 3mm;

[0043] Step 6, analyze each parameter in step 5;

[0044] Further, the porosity, pore wall and microstructure of the coke before reaction are combined with each parameter in step 5 for analysis and research;

[0045] Step 7, construct a comprehensive evaluation method system of coke smelting performance.

[0046] The present application provides a technical scheme for scientifically and effectively evaluating the smelting performance of metallurgical coke, which is a new technical parameter for innovative characterization of a conventional detection process, solves the technical problems of difficult effective evaluation of the smelting loss process of metallurgical coke and the “black box” of metallurgical coke in a blast furnace, and is a new evaluation system method for the use process of metallurgical coke, which can more scientifically understand metallurgical coke, especially the intuitive parameter characterization of the smelting loss process of metallurgical coke in a blast furnace, and provides a systematic method for understanding metallurgical coke, a cognitive method for different volume blast furnaces using differentiated coke, and important and practical significance for the stable operation and economic index improvement of a blast furnace, and good guiding significance for scientific coal blending, optimization of the technical structure of coal blending, and reduction of the cost of coal blending coking, thereby generating huge economic benefits and good social benefits.

[0047] In order to better illustrate the present patent technology, the metallurgical coke produced by a coking plant of a certain steel joint enterprise is evaluated in terms of the post-reaction strength microstructure performance and the powder coke rate.

[0048] The metallurgical coke production of the steel joint enterprise is 7-meter top-charged coke oven production. The coal blending structure is shown in Table 1.

[0049] Table 1 Coal blending structure

[0050]

[0051] The test sample is comprehensively analyzed and detected, and the parameters such as coke porosity, pore wall thickness, and coke microstructure are detected. The detection values are shown in Table 2.

[0052] Table 2 Sample detection values

[0053]

[0054] According to the national detection technical standard GB / T4000 “Detection method for reactivity and post-reaction strength of metallurgical coke”, the research coke to be analyzed and studied is detected and analyzed. After the thermal reactivity of the coke is discharged from the drum, the original detection method is increased to nine levels of sieve screening of the reaction product by using 18 mm, 15 mm, 10 mm, 8 mm, 5 mm, 3 mm, 2 mm, 1 mm, and 0.2 mm sieves, respectively, and the percentage mass of each particle size is calculated. The detection data limit is shown in Table 3.

[0055] Table 3 Detection mass percentage of reaction product screened by nine levels of sieves

[0056]

[0057] Through the data analysis of the above table, after the coke thermal performance detection and multi-stage screen screening, the reaction coke of 3mm or more accounts for 71.04% of the total amount of the reaction coke, the reaction coke of 1mm or less accounts for 26.16% of the total amount of the reaction coke, and the reaction coke of 0.2mm or less accounts for 16% of the total amount of the reaction coke. The analysis of the thermal reaction coke screening composition can clearly determine the melting loss of the coke in the state of carbon dioxide. The higher the pulverization rate of the coke, the more intense the melting loss reaction of the coke, which indicates that the ability of the coke to resist carbon dioxide is poor, and the quality performance of the coke is not good.

[0058] Analyzing the data of each stage of the coke after the thermal reaction, the melting loss reaction of the coke in the blast furnace directly represents the metallurgical coke that is continuously melted and lost, and the coke particle size gradually becomes smaller and more fragmented due to gas erosion, and the coke fines increase. Corresponding to the present application, the coke of less than 3mm after the reaction increases, so that the melting ability of the metallurgical coke in the blast furnace can be represented by this index, thereby providing new parameter support for the blast furnace adaptability coke.

[0059] The pore rate, pore wall and microstructure of the coke of 3mm or more after the reaction are detected, and the detection values are shown in Table 4.

[0060] Table 4 Pore analysis values of the coke of 3mm or more after the reaction

[0061]

[0062] The open pores and closed pores are formed when the gas is precipitated. The former is the gas that is decomposed in the coking process and is precipitated through the channel, so it is connected with the outside world. The latter is formed because the decomposed gas is blocked by the surrounding colloid and cannot be precipitated. Most of the coke (more than 90%) is open pores, and the rest is closed pores. The open pores directly affect the carbon dissolution reaction of the coke, and then affect the strength. The closed pores affect the matrix structure of the coke. In the carbon dissolution reaction process, the open pores continuously merge and grow, which may make the closed pores penetrate, affecting the reactivity of the coke. From the data analysis in Table 4, the pore rate of the coke after the reaction increases, the pore wall becomes thinner, and the average diameter of the pores increases, which all represent that the coke is melting, and the internal structure of the coke is changing deeply.

[0063] The coke smelting performance comprehensive evaluation method system is formed by the above implementation process of the patent, which guides the stable operation of the blast furnace.

[0064] The above-described embodiments only describe the preferred modes of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements of the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. A method for evaluating the smelting performance of metallurgical coke by coke powder rate, characterized by: Specifically comprising the following steps: Step 1, comprehensively analyzing and detecting the test sample, focusing on detecting the coke porosity, pore wall thickness, and coke microstructure parameters; Step 2, detecting and analyzing the coke to be analyzed according to the national detection technical standard GB / T4000 "Metallurgical coke reactivity and post-reaction strength detection method"; Step 3, after the end of the coke heat reaction process, the reaction material is sieved by 18mm, 15mm, 10mm, 8mm, 5mm, 3mm, 2mm, 1mm and 0.2mm nine sieves; after sieving by the nine sieves, the percentage content of each particle size is calculated; the weight percentage of ≤3mm to the weight of the post-reaction is used to represent the powder coke rate; the weight percentage of ≤1mm to the weight of the post-reaction is used to represent the fine powder coke rate; the columnar analysis graph and trend graph of each particle size sieve residue are drawn respectively; Step 4, analyzing the numerical values of the parameters in step 3; The new characterization parameters after the reaction describe the melting ability of the coke in the blast furnace, thereby providing new parameter support for the blast furnace adaptability coke; Step 5, detecting the porosity, pore wall and microstructure of the coke with a particle size of more than 3mm after the reaction; Step 6, analyzing the parameters in step 5; combining and analyzing the porosity, pore wall and microstructure of the coke before the reaction with the parameters in step 5; Step 7, constructing a comprehensive evaluation method system for the smelting performance of coke.

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