Method for predicting coke quality by using coking coal vitrinite reflectance, inert component content and gieseler maximum fluidity

Abstract

This invention relates to a method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum flowability of coking coal. The method characterizes and quantifies the quality properties of individual coal types using vitrinite reflectance, inert component content, and Gibbs maximum flowability. A ternary control chart is established using mathematical methods to evaluate the quality of coking coal, providing effective guidance for coking coal blending, thereby achieving the goal of controlling and improving coke quality.

Description

Technical Field

[0001] This invention relates to the field of coking technology, and in particular to a method for predicting coke quality using the vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal. Background Technology

[0002] Coke is an irregular, porous carbonaceous material containing cracks and defects. It is the primary raw material and fuel for blast furnace smelting and must possess high cold strength to resist mechanical impact and abrasion during its descent in a blocky zone. The crushing strength of coke refers to its ability to withstand external impact forces without breaking along structural cracks or defects. The abrasion resistance of coke refers to its ability to resist frictional forces without producing surface debris or powder.

[0003] In recent years, with the development of blast furnace smelting technology, especially the development of larger blast furnace volumes, high blast temperature technology, and oxygen-enriched pulverized coal injection technology, the role of coke in the blast furnace's burden support structure and its function in ensuring air and liquid permeability have become more prominent. This not only requires the coke in the blast furnace to have a certain degree of crush resistance (to support the upper burden) and a certain degree of abrasion resistance to maintain the blast furnace's permeability, but also places higher demands on the coke's thermal reactivity and post-reaction strength.

[0004] The thermal reactivity of coke primarily simulates its ability to undergo a gasification reaction (dissolution reaction) with CO2 before entering the tuyeres of a blast furnace. The gasification reaction between coke and carbon dioxide leads to erosion, causing weight loss and cracking, thinning of the internal pore walls, reduced coke strength, and accelerated breakage. Excessive reactivity in the softening zone results in poorer gas utilization, a higher coke ratio, and increased coke breakage producing more fragments and coke powder, further deteriorating the permeability of the blast furnace burden and hindering smooth operation. Coke thermal reactivity significantly impacts blast furnace smelting, becoming a key factor limiting the stable, balanced, high-quality, and efficient production of molten iron. To increase the carbon dioxide content in the top gas, improve gas utilization, optimize hearth temperature and gas flow distribution, facilitate smooth burden descent, and improve the coke skeleton's support function, the thermal reactivity (CRI) of coke at a given temperature must be minimized.

[0005] Coke post-reaction strength (CSR) measures the ability of coke to maintain its strength at high temperatures under conditions of CO2 and alkali metal corrosion. Coke undergoes a gasification reaction with carbon dioxide, and the corrosion process causes weight loss and cracking, thinning of the internal pore walls, reducing coke strength, and accelerating coke breakage. Excessive reactivity of coke in the softening zone leads to poorer gas utilization, an increased coke ratio, and more coke breakage producing fragments and coke powder, which also worsens the permeability of the blast furnace burden, affecting smooth blast furnace operation. Coke post-reaction strength has a significant impact on blast furnace smelting, becoming one of the key factors limiting the stable, balanced, high-quality, and efficient production of molten iron. To increase the carbon dioxide content in the top gas, improve gas utilization, optimize hearth temperature and gas flow distribution, facilitate smooth burden descent, and improve the support of the coke skeleton, the coke post-reaction strength (CSR) should be as high as possible at a given temperature.

[0006] These quality requirements for coke implicitly place higher demands on coking coal blending. It is necessary to conduct in-depth research on the impact of the quality of a single type of coal on the coke's crush resistance, abrasion resistance, thermal reactivity, and post-reaction strength, establish corresponding control models, and optimize coal blending to precisely control the coke quality within the range required for blast furnace operation.

[0007] Establishing predictive models and control methods for coke's shatter resistance, abrasion resistance, thermal reactivity, and post-reaction strength is of great significance for coking plants in selecting economical coal blending ratios, predicting and controlling coke quality, and managing coal yards. Due to differences in coal resources across countries, varying coal utilization strategies among coking plants, and differences in evaluation indicators and testing methods, the prediction methods for coke shatter resistance, abrasion resistance, thermal reactivity, and post-reaction strength also differ. In recent years, researchers both domestically and internationally have conducted extensive research on predicting coke shatter resistance, abrasion resistance, thermal reactivity, and post-reaction strength to improve coke quality. These studies can be broadly categorized as follows:

[0008] (1) Prediction using coal and rock parameters, such as the SI-CBI method (Intensity Index and Composition Balance Index) in the United States;

[0009] (2) Prediction using volatile matter and process parameters, such as the VY method (volatile matter-colloidal layer index method), VG method (volatile matter-binding index method) commonly used in my country, the V-TD method (volatile matter-total expansion method) in the UK, and the V-CSN method (volatile matter-crucible expansion ordinal number method) in Canada.

[0010] (3) Prediction using volatile matter and process parameters, such as the RG method (vitrinite reflectance-adhesion index method) and the Japanese MOF method (vitrinite reflectance-Gilead maximum flowability method).

[0011] (4) Prediction using coking process conditions, such as the German G-factor method.

[0012] (5) Prediction can be made using coal ash catalytic index, such as the MCI index method or the MBI index method.

[0013] The properties of coking coal mainly depend on its degree of metamorphism, caking and melting properties, and the content and ratio of active and inert components in the coal. Coal petrification uses vitrinite reflectance to characterize the degree of coalification and inert component content and optimal ratio to characterize the component balance index, but lacks characterization of the coal's technological properties.

[0014] The composition and structure of coking coal are very complex and highly heterogeneous. The process parameters mentioned above can only represent one aspect of the process characteristics of coking coal and cannot reflect the differences in the quality of coal petrographic components and vitrinite.

[0015] Coking coals with similar metamorphic degrees and petrographic compositions may exhibit significant differences in their coking characteristics. Relying solely on vitrinite reflectance and petrographic component content to predict coke's crushing strength, abrasion resistance, thermal reactivity, or post-reaction strength has limitations. Differences in petrographic parameters are insufficient to reflect the plastic changes in coking coal during heating. Therefore, parameters reflecting plastic changes are needed to compensate for the shortcomings of petrographic parameters. Summary of the Invention

[0016] This invention provides a method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum flowability of coking coal. Based on coal-rock blending theory, a ternary coal blending model is established using parameters such as vitrinite reflectance, inert component content, and Gibbs maximum flowability of a single type of coking coal. Control charts are then established for coke crushing strength, coke abrasion resistance, coke thermal reactivity, and coke post-reaction strength, providing effective guidance for coking coal blending and achieving the goal of controlling and improving coke quality.

[0017] To achieve the above objectives, the present invention employs the following technical solution:

[0018] A method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal is proposed. The method uses vitrinite reflectance, inert component content, and Gibbs maximum fluidity to characterize and quantify the quality characteristics of a single type of coal. A ternary control chart is established using mathematical methods to evaluate the quality of coking coal, based on which the quality of coke is controlled.

[0019] A method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal, specifically includes the following steps:

[0020] 1) Conduct vitrinite reflectance tests on individual coal types to obtain the vitrinite reflectance of each type of coal.

[0021] 2) Quantitative analysis of coal petrographic components: The contents of vitrinite (V), inertinite (I), and chitinite (E) in each type of coal were tested. Assuming the relative density of the petrographic components in coking coal is 1.35 and the relative density of the minerals is 2.8, the mass fraction of the minerals is calculated using the Parr formula:

[0022] 1.08×A d +0.55×S t,d ...(Equation 1)

[0023] In the formula: A d —Dry basis ash content, mass fraction %;

[0024] S t,d— Total sulfur content on a dry basis, mass fraction %.

[0025] The mineral volume content MM is corrected by ash and sulfur content, as shown in equation (2):

[0026]

[0027] The inert component content TI of a single type of coal is calculated according to formula (3):

[0028] TI = I + MM……(Equation 3)

[0029] 3) Perform Gibbs maximum flowability test to obtain the Gibbs maximum flowability lgMF for a single type of coal;

[0030] 4) Conduct coke quality tests, including coke shatter resistance test, coke abrasion resistance test, coke thermal reactivity test, and coke post-reaction strength test; obtain the coke shatter resistance M of a single type of coal. 40 Coke abrasion resistance M 10 Coke thermal reactivity (CRI) and coke post-reaction strength (CSR) are also mentioned.

[0031] 5) Data normalization; for vitrinite reflectance The inert component content (TI) and Gibbs maximum flow rate (lgMF) were normalized using the following normalization equation:

[0032]

[0033] In the formula: R i —The normalized properties of the i-th single type of coal; r i —Properties of the i-th single type of coal; r max —The maximum value of property r; r min —The minimum value of property r;

[0034] 6) Draw coke quality control charts, including coke crush strength control chart, coke abrasion resistance control chart, coke thermal reactivity control chart, and coke post-reaction strength control chart; among which:

[0035] The coke crush resistance control chart is based on vitrinite reflectance. With the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a coke crush resistance strength M is established in a triangular coordinate system. 40 Contour map;

[0036] The coke abrasion resistance control chart is based on vitrinite reflectance. With the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a coke abrasion resistance M is established in a triangular coordinate system. 10 Contour map;

[0037] The coke thermal reactivity control chart is based on vitrinite reflectance. Using the X-axis as the inert component content TI as the Y-axis and the Gibbs maximum fluidity lgMF as the Z-axis, a contour map of the coke thermal reactivity CRI is established in a triangular coordinate system.

[0038] The intensity control chart after coke reaction is based on vitrinite reflectance. Using the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a contour map of the coke reaction strength CSR is established in a triangular coordinate system.

[0039] Furthermore, in step 1), the vitrinite reflectance of a single type of coal, i.e., the average maximum vitrinite reflectance, is specifically tested according to GB / T 6948-2008 "Microscopic Determination of Vitrinite Reflectance of Coal", with no fewer than 100 test points. The mean value μ of the test data is calculated, which is the vitrinite reflectance.

[0040] Furthermore, in step 2), the contents of vitrinite V, inertinite I, and chitinite E in each type of coal are tested according to GB / T 8899-201 "Methods for Microscopic Grouping and Mineral Determination of Coal".

[0041] Furthermore, in step 3), the maximum Gibbs flowability lgMF of a single type of coal is tested according to GB / T 25213-2010 "Coal Plasticity Constant Torque Gibbs Plasticity Tester Method".

[0042] Furthermore, in step 4), the coke shatter resistance strength is tested using a coke oven experiment, as detailed below:

[0043] Single-type coke was prepared using a 40kg coke oven; the crushing strength M of the coke was tested using a Micum drum test according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". 40 Take coke and sieve it using a vibrating screen. For coke with a particle size greater than 60 mm, perform a Micum drum test. After 100 revolutions, let it stand for 1 to 2 minutes. Then, sieve the obtained coke using a 40 mm screen and weigh it.

[0044] Crushing strength of coke: M 40 =m1 / m×100%……(Equation 5)

[0045] In the formula, m: mass of coke entering the drum, kg;

[0046] m1: The mass of coke larger than 40mm after exiting the drum, in kg.

[0047] Furthermore, in step 4), the abrasion resistance of coke is tested using a coke oven experiment, as detailed below:

[0048] Single-type coke was prepared using a 40kg coke oven; the abrasion resistance M of the coke was tested using a Micum drum tester according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". 10 Take coke and sieve it using a vibrating screen. For coke with a particle size greater than 60 mm, perform a Micum drum test. After 100 revolutions, let it stand for 1 to 2 minutes. Then, sieve the obtained coke using a 10 mm screen and weigh it.

[0049] Abrasion resistance of coke: M 10 = m² / m × 100%……(Equation 6)

[0050] In the formula, m: mass of coke entering the drum, kg;

[0051] m2: The mass of coke smaller than 10mm after exiting the drum, in kg.

[0052] Furthermore, in step 4), the thermal reactivity of coke is tested using a coke oven experiment, as detailed below:

[0053] The thermal reactivity (CRI) of coke was tested according to GB / T 4000-2008 "Test Methods for Reactivity and Post-Reaction Strength of Coke"; a value greater than [missing value] was taken. 20 kg of coke was crushed and reduced in size using a jaw crusher, yielding 10 kg. Circular hole sieve sieving, for sizes larger than The coke blocks are further crushed and screened to produce... coke;

[0054] Weigh 200±0.5g of coke was placed in a high-temperature alloy steel reactor or a corundum reactor and reacted with carbon dioxide at a flow rate of 5L / min at 1100℃±5℃ for 2h. The coke reactivity CRI was expressed as the percentage of coke mass loss.

[0055] CRI = (m³ - m⁴) / m × 100% … (Equation 7)

[0056] In the formula, m3: mass of coke before reaction, g;

[0057] m4: Mass of residual coke after reaction, in grams.

[0058] Furthermore, in step 4), the strength of the coke after reaction is tested using a coke oven experiment, as detailed below:

[0059] The post-reaction strength (CSR) of coke was tested according to GB / T 4000-2008 "Test Methods for Reactivity and Post-Reaction Strength of Coke"; a value greater than 100% was taken. 20 kg of coke was crushed and reduced to 10 kg using a jaw crusher; Circular hole sieve sieving, for sizes larger than The coke blocks are further crushed and screened to produce... coke;

[0060] Weigh 200±0.5g of coke was placed in a high-temperature alloy steel reactor or a corundum reactor and reacted with carbon dioxide at a flow rate of 5L / min at 1100℃±5℃ for 2h. After a Type I drum test, the coke strength CSR after reaction was expressed as the mass fraction of coke with particle size greater than 10mm in the coke after reaction.

[0061] CSR=(m5-m6) / m×100%……(Equation 8)

[0062] In the formula, m5: mass of residual coke after reaction, g;

[0063] m6: Mass of coke particles larger than 10mm after drum rotation, in g.

[0064] Furthermore, in step 6), the data analysis methods used include polynomial regression, inverse distance weighted interpolation, Kriging, minimum curvature method, improved Shepard method, natural neighbor method, nearest neighbor method, radial basis function method, linear interpolation triangular network method, moving average method, and local polynomial method.

[0065] Compared with the prior art, the beneficial effects of the present invention are:

[0066] 1) Based on the theory of coal and rock blending, a ternary coal blending model is established using parameters such as vitrinite reflectance, inert component content and Gibbs maximum fluidity of a single type of coking coal. Control charts are established for coke crushing strength, coke abrasion resistance, coke thermal reactivity and coke post-reaction strength, providing effective guidance for coking coal blending and achieving the goal of controlling and improving coke quality.

[0067] 2) During the coking process, coking coal forms two parts: a fusible component (active component) and an infusible component (inert component). Vitrin reflectance is the most scientifically accurate parameter for characterizing the degree of metamorphism of coking coal. For coking coal at a certain metamorphic stage, only when the inert and active components are mixed in the most suitable ratio can coke with good shatter resistance be produced.

[0068] 3) Gibbs maximum flowability reflects both the quantity and quality of the plastic mass. The higher the Gibbs maximum flowability of coking coal, the better the fluidity of the plastic mass, which can flow fully between coal particles and bind solid particles to obtain higher quality coke. Gibbs maximum flowability has a strong ability to distinguish the binding characteristics of low-rank coking coal and is more sensitive to changes in the properties of coking coal. It is suitable for low-rank coking coal and situations with diverse coal sources.

[0069] 4) The design of this invention is reasonable. It scientifically characterizes and quantifies the quality characteristics of a single type of coking coal by using vitrinite reflectance, inert component content, and Gibbs maximum fluidity. It uses mathematical methods to establish a ternary control chart for four coke quality-related indicators, which effectively overcomes the shortcomings of current coking coal use and coking coal blending processes, realizes the scientific evaluation of coking coal quality, and provides quantitative guidance for precise control of coke quality, thereby achieving the goal of stabilizing and improving coke quality.

[0070] 5) The method described in this invention is simple to operate and easy to implement, and can effectively improve the quality stability of coke used in blast furnaces. Attached Figure Description

[0071] Figure 1 The coke crush resistance M described in the embodiments of the present invention 40 Three-dimensional control chart.

[0072] Figure 2 The coke crushing strength M of coal blending scheme 1 in this embodiment of the invention. 40 Predicted area (shaded area in the figure).

[0073] Figure 3 The coke crushing strength M of coal blending scheme 2 in this embodiment of the invention. 40 Predicted area (shaded area in the figure).

[0074] Figure 4 The coke crushing strength M of coal blending scheme 3 in this embodiment of the invention. 40 Predicted area (shaded area in the figure).

[0075] Figure 5 The coke abrasion resistance M described in the embodiments of the present invention 10 Three-dimensional control chart.

[0076] Figure 6 The coke abrasion resistance M of coal blending scheme 1 in this embodiment of the invention. 10 Predicted area (shaded area in the figure).

[0077] Figure 7 The coke abrasion resistance M of coal blending scheme 2 in this embodiment of the invention. 10 Predicted area (shaded area in the figure).

[0078] Figure 8 The coke abrasion resistance M of coal blending scheme 3 in this embodiment of the invention. 10 Predicted area (shaded area in the figure).

[0079] Figure 9 This is a ternary control chart of coke thermal reactivity CRI as described in an embodiment of the present invention.

[0080] Figure 10 The shaded area in the figure represents the CRI prediction region for coke thermal reactivity in coal blending scheme 1 of this embodiment of the invention.

[0081] Figure 11 The shaded area in the figure represents the CRI prediction region for coke thermal reactivity in coal blending scheme 2 of this embodiment of the invention.

[0082] Figure 12 The shaded area in the figure represents the CRI prediction region for coke thermal reactivity in coal blending scheme 3 of this embodiment of the invention.

[0083] Figure 13 This is a ternary control chart of the coke post-reaction strength (CSR) as described in an embodiment of the present invention.

[0084] Figure 14 The area shown in the figure is the predicted coke reaction strength (CSR) region for coal blending scheme 1 in this embodiment of the invention.

[0085] Figure 15 The area shown in the figure is the predicted coke reaction strength (CSR) region for coal blending scheme 2 in this embodiment of the invention (shaded area).

[0086] Figure 16 The area shown in the figure is the predicted coke reaction strength (CSR) region for coal blending scheme 3 in this embodiment of the invention (shaded area). Detailed Implementation

[0087] This invention describes a method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum flowability of coking coal. The method characterizes and quantifies the quality characteristics of a single type of coal using vitrinite reflectance, inert component content, and Gibbs maximum flowability. A ternary control chart is established using mathematical methods to evaluate the quality of coking coal, based on which the quality of coke is controlled.

[0088] The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal, as described in this invention, specifically includes the following steps:

[0089] 1) Conduct vitrinite reflectance tests on individual coal types to obtain the vitrinite reflectance of each type of coal.

[0090] 2) Quantitative analysis of coal petrographic components: The contents of vitrinite (V), inertinite (I), and chitinite (E) in each type of coal were tested. Assuming the relative density of the petrographic components in coking coal is 1.35 and the relative density of the minerals is 2.8, the mass fraction of the minerals is calculated using the Parr formula:

[0091] 1.08×A d +0.55×S t,d ...(Equation 1)

[0092] In the formula: A d —Dry basis ash content, mass fraction %;

[0093] S t,d— Total sulfur content on a dry basis, mass fraction %.

[0094] The mineral volume content MM is corrected by ash and sulfur content, as shown in equation (2):

[0095]

[0096] The inert component content TI of a single type of coal is calculated according to formula (3):

[0097] TI = I + MM……(Equation 3)

[0098] 7) Perform Gibbs maximum fluidity test to obtain the Gibbs maximum fluidity lgMF for a single type of coal;

[0099] 8) Conduct coke quality tests, including coke shatter resistance test, coke abrasion resistance test, coke thermal reactivity test, and coke post-reaction strength test; obtain the coke shatter resistance M of a single type of coal. 40 Coke abrasion resistance M 10 Coke thermal reactivity (CRI) and coke post-reaction strength (CSR) are also mentioned.

[0100] 9) Data normalization; for vitrinite reflectance The inert component content (TI) and Gibbs maximum flow rate (lgMF) were normalized using the following normalization equation:

[0101]

[0102] In the formula: R i —The normalized properties of the i-th single type of coal; r i —Properties of the i-th single type of coal; r max —The maximum value of property r; r min —The minimum value of property r;

[0103] 10) Draw coke quality control charts, including coke crush strength control chart, coke abrasion resistance control chart, coke thermal reactivity control chart, and coke post-reaction strength control chart; among which:

[0104] The coke crush resistance control chart is based on vitrinite reflectance. With the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a coke crush resistance strength M is established in a triangular coordinate system. 40 Contour map;

[0105] The coke abrasion resistance control chart is based on vitrinite reflectance. With the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a coke abrasion resistance M is established in a triangular coordinate system. 10 Contour map;

[0106] The coke thermal reactivity control chart is based on vitrinite reflectance. Using the X-axis as the inert component content TI as the Y-axis and the Gibbs maximum fluidity lgMF as the Z-axis, a contour map of the coke thermal reactivity CRI is established in a triangular coordinate system.

[0107] The intensity control chart after coke reaction is based on vitrinite reflectance. Using the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a contour map of the coke reaction strength CSR is established in a triangular coordinate system.

[0108] Furthermore, in step 1), the vitrinite reflectance of a single type of coal, i.e., the average maximum vitrinite reflectance, is specifically tested according to GB / T 6948-2008 "Microscopic Determination of Vitrinite Reflectance of Coal", with no fewer than 100 test points. The mean value μ of the test data is calculated, which is the vitrinite reflectance.

[0109] Furthermore, in step 2), the contents of vitrinite V, inertinite I, and chitinite E in each type of coal are tested according to GB / T 8899-201 "Methods for Microscopic Grouping and Mineral Determination of Coal".

[0110] Furthermore, in step 3), the maximum Gibbs flowability lgMF of a single type of coal is tested according to GB / T 25213-2010 "Coal Plasticity Constant Torque Gibbs Plasticity Tester Method".

[0111] Furthermore, in step 4), the coke shatter resistance strength is tested using a coke oven experiment, as detailed below:

[0112] Single-type coke was prepared using a 40kg coke oven; the crushing strength M of the coke was tested using a Micum drum test according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". 40 Take coke and sieve it using a vibrating screen. For coke with a particle size greater than 60 mm, perform a Micum drum test. After 100 revolutions, let it stand for 1 to 2 minutes. Then, sieve the obtained coke using a 40 mm screen and weigh it.

[0113] Crushing strength of coke: M 40 =m1 / m×100%……(Equation 5)

[0114] In the formula, m: mass of coke entering the drum, kg;

[0115] m1: The mass of coke larger than 40mm after exiting the drum, in kg.

[0116] Furthermore, in step 4), the abrasion resistance of coke is tested using a coke oven experiment, as detailed below:

[0117] Single-type coke was prepared using a 40kg coke oven; the abrasion resistance M of the coke was tested using a Micum drum tester according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". 10 Take coke and sieve it using a vibrating screen. For coke with a particle size greater than 60 mm, perform a Micum drum test. After 100 revolutions, let it stand for 1 to 2 minutes. Then, sieve the obtained coke using a 10 mm screen and weigh it.

[0118] Abrasion resistance of coke: M 10 = m² / m × 100%……(Equation 6)

[0119] In the formula, m: mass of coke entering the drum, kg;

[0120] m2: The mass of coke smaller than 10mm after exiting the drum, in kg.

[0121] Furthermore, in step 4), the thermal reactivity of coke is tested using a coke oven experiment, as detailed below:

[0122] The thermal reactivity (CRI) of coke was tested according to GB / T 4000-2008 "Test Methods for Reactivity and Post-Reaction Strength of Coke"; a value greater than [missing value] was taken. 20 kg of coke was crushed and reduced in size using a jaw crusher, yielding 10 kg. Circular hole sieve sieving, for sizes larger than The coke blocks are further crushed and screened to produce... coke;

[0123] Weigh 200±0.5g of coke was placed in a high-temperature alloy steel reactor or a corundum reactor and reacted with carbon dioxide at a flow rate of 5L / min at 1100℃±5℃ for 2h. The coke reactivity CRI was expressed as the percentage of coke mass loss.

[0124] CRI = (m³ - m⁴) / m × 100% … (Equation 7)

[0125] In the formula, m3: mass of coke before reaction, g;

[0126] m4: Mass of residual coke after reaction, in grams.

[0127] Furthermore, in step 4), the strength of the coke after reaction is tested using a coke oven experiment, as detailed below:

[0128] The post-reaction strength (CSR) of coke was tested according to GB / T 4000-2008 "Test Methods for Reactivity and Post-Reaction Strength of Coke"; a value greater than 100% was taken. 20 kg of coke was crushed and reduced to 10 kg using a jaw crusher; Circular hole sieve sieving, for sizes larger than The coke blocks are further crushed and screened to produce... coke;

[0129] Weigh 200±0.5g of coke was placed in a high-temperature alloy steel reactor or a corundum reactor and reacted with carbon dioxide at a flow rate of 5L / min at 1100℃±5℃ for 2h. After a Type I drum test, the coke strength CSR after reaction was expressed as the mass fraction of coke with particle size greater than 10mm in the coke after reaction.

[0130] CSR=(m5-m6) / m×100%……(Equation 8)

[0131] In the formula, m5: mass of residual coke after reaction, g;

[0132] m6: Mass of coke particles larger than 10mm after drum rotation, in g.

[0133] Furthermore, in step 6), the data analysis methods used include polynomial regression, inverse distance weighted interpolation, Kriging, minimum curvature method, improved Shepard method, natural neighbor method, nearest neighbor method, radial basis function method, linear interpolation triangular network method, moving average method, and local polynomial method.

[0134] To make the objectives, technical solutions, and technical effects of this invention clearer, the technical solutions in the embodiments of this invention are now described clearly and completely. However, the embodiments described below are only some embodiments of this invention, not all embodiments. All other embodiments obtained by those skilled in the art in conjunction with the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0135] The following three examples illustrate the use of coking coal from a large coking plant with four 52-hole JNX70-2 type reheating and down-regulating coke ovens and an annual coke production of 2.55 million tons.

[0136]

Example 1

[0137] Coal blending scheme 1 uses eight types of single coal. The quality characteristics of each type of coal and the coke index are shown in Table 1. The parameters of the quality characteristics of each type of coal after normalization are shown in Table 2.

[0138] Table 1 Quality characteristics of single types of coal and various coke indicators

[0139]

[0140] Table 2. Parameters after normalization of quality characteristics of single coal types.

[0141]

[0142] The experimental mixes of eight single coal types are shown in Table 3. The weighted value of R is 48.35 (normalized), the weighted value of TI is 50.786 (normalized), and the weighted value of lgMF is 47.498 (normalized).

[0143] Table 3 Experimental proportions

[0144] Ratio / % 12 16 18 12 10 14 8 10

[0145] This embodiment utilizes a ternary control chart of coke crush resistance strength (such as...). Figure 1 (As shown), calculate the crushing strength M of this blended coal. 40 ( Figure 2 (Middle shaded area). This embodiment utilizes the shatter resistance M of coke produced in a 40kg coke oven. 40 The result was 67.9%, which is within the control range of the predicted value, with minimal deviation.

[0146] This embodiment utilizes a three-dimensional control chart of coke abrasion resistance (such as...). Figure 5 (As shown), calculate the abrasion resistance M of this blended coal. 10 ( Figure 6 (Middle shaded area). This embodiment utilizes the abrasion resistance M of coke produced in a 40kg coke oven. 10 The figure was 13.1%, which is within the control range of the predicted value, with a very small deviation.

[0147] This embodiment utilizes a ternary control chart of coke thermal reactivity (such as...). Figure 9 As shown), calculate the thermal reactivity CRI of this blended coal. Figure 10 (Middle shaded area). In this embodiment, the thermal reactivity CRI of coke produced using a 40kg coke oven is 28.6%, which is within the control range of the predicted value and the deviation is minimal.

[0148] This embodiment utilizes a ternary control chart of coke intensity after reaction (such as...). Figure 13 As shown), calculate the post-reaction strength (CSR) of this blended coal. Figure 14 (Middle shaded area). In this embodiment, the post-reaction strength (CSR) of coke produced in a 40kg coke oven is 58.9%, which is within the control range of the predicted value with minimal deviation.

[0149]

Example 2

[0150] Coal blending scheme 2 uses eight types of single coal. The quality characteristics of each type of coal and the coke indicators are shown in Table 4. The parameters of the quality characteristics of each type of coal after normalization are shown in Table 5.

[0151] Table 4 Quality characteristics of single coal types and various coke indices

[0152]

[0153] Table 5. Parameters after normalization of quality characteristics of single coal types.

[0154]

[0155] The experimental mixes of eight single coal types are shown in Table 6. The weighted value of R is 44.252 (normalized), the weighted value of TI is 51.364 (normalized), and the weighted value of lgMF is 74.694 (normalized).

[0156] Table 6 Experimental Proportions

[0157] Ratio / % 10 20 12 20 16 8 8 6

[0158] This embodiment utilizes a ternary control chart of coke crush resistance strength (such as...). Figure 1 (As shown), calculate the crushing strength M of this blended coal. 40 ( Figure 3(Middle shaded area). This embodiment utilizes the shatter resistance M of coke produced in a 40kg coke oven. 40 The result was 71.2%, which is within the control range of the predicted value, with minimal deviation.

[0159] This embodiment utilizes a three-dimensional control chart of coke abrasion resistance (such as...). Figure 5 (As shown), calculate the abrasion resistance M of this blended coal. 10 ( Figure 7 (Middle shaded area). This embodiment utilizes the abrasion resistance M of coke produced in a 40kg coke oven. 10 The value was 10.9%, which is within the control range of the predicted value, with minimal deviation.

[0160] This embodiment utilizes a ternary control chart of coke thermal reactivity (such as...). Figure 9 As shown), calculate the thermal reactivity CRI of this blended coal. Figure 11 (Middle shaded area). In this embodiment, the thermal reactivity CRI of coke produced using a 40kg coke oven is 24.3%, which is within the control range of the predicted value and the deviation is minimal.

[0161] This embodiment utilizes a ternary control chart of coke intensity after reaction (such as...). Figure 13 As shown), calculate the post-reaction strength (CSR) of this blended coal. Figure 15 (Middle shaded area). In this embodiment, the post-reaction strength (CSR) of coke produced in a 40kg coke oven is 62.4%, which is within the control range of the predicted value with minimal deviation.

[0162]

Example 3

[0163] Coal blending scheme 3 uses 6 types of single coal. The quality characteristics of each single coal and the coke index are shown in Table 7. The parameters of the quality characteristics of the single coal after normalization are shown in Table 8.

[0164] Table 7 Quality characteristics of single types of coal and various coke indicators

[0165]

[0166] Table 8. Parameters after normalization of quality characteristics of single coal types.

[0167]

[0168] The proposed blending ratios for the six single coal types are shown in Table 9. The weighted average value of R is 68.472 (normalized), the weighted average value of TI is 45.776 (normalized), and the weighted average value of lgMF is 50.334 (normalized).

[0169] Table 9 Experimental Proportions

[0170] Ratio / % 8 22 26 20 16 8

[0171] This embodiment utilizes a ternary control chart of coke crush resistance strength (such as...). Figure 1 (As shown), calculate the crushing strength M of this blended coal. 40 ( Figure 4 (Middle shaded area). This embodiment utilizes the shatter resistance M of coke produced in a 40kg coke oven. 40 The result was 69.3%, which is within the control range of the predicted value, with minimal deviation.

[0172] This embodiment utilizes a three-dimensional control chart of coke abrasion resistance (such as...). Figure 5 (As shown), calculate the abrasion resistance M of this blended coal. 10 ( Figure 8 (Middle shaded area). This embodiment utilizes the abrasion resistance M of coke produced in a 40kg coke oven. 10 The result was 10.7%, which is within the control range of the predicted value, with minimal deviation.

[0173] This embodiment utilizes a ternary control chart of coke thermal reactivity (such as...). Figure 9 As shown), calculate the thermal reactivity CRI of this blended coal. Figure 12 (Middle shaded area). In this embodiment, the thermal reactivity CRI of coke produced using a 40kg coke oven is 25.5%, which is within the control range of the predicted value and the deviation is minimal.

[0174] This embodiment utilizes a ternary control chart of coke intensity after reaction (such as...). Figure 13 As shown), calculate the post-reaction strength (CSR) of this blended coal. Figure 16 (Middle shaded area). In this embodiment, the post-reaction strength (CSR) of coke produced in a 40kg coke oven is 61.3%, which is within the control range of the predicted value with minimal deviation.

[0175] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal, characterized in that, The quality characteristics of individual coal types are characterized and quantified using vitrinite reflectance, inert component content, and Gibbs maximum fluidity. A ternary control chart is established mathematically to evaluate the quality of coking coal, assessing its shatter resistance, abrasion resistance, thermal reactivity, and post-reaction strength. Based on this evaluation, coke quality is controlled. The specific steps include: 1) Single coal vitrinite reflectance test is conducted to obtain single coal vitrinite reflectance R o max ; 2) Quantitative analysis of coal petrographic components: The contents of vitrinite (V), inertinite (I), and chrysinite (E) in each type of coal were tested. Assuming the relative density of the petrographic components in coking coal is 1.35 and the relative density of the minerals is 2.8, the mass fraction of the minerals is calculated using the Parr formula: 1.08 x A d + 0.55 x S t,d (Formula 1) In the formula: A d - dry basis ash, mass %; S t,d - dry basis total sulfur content, mass %; The mineral volume content MM is corrected by ash and sulfur content, as shown in equation (2): (Equation 2) The inert component content TI of a single type of coal is calculated according to formula (3): TI = I + MM (Equation 3) The Gibbs maximum fluidity test was conducted to obtain the Gibbs maximum fluidity lgMF for a single type of coal. Coke quality tests were conducted, including coke crush resistance test, coke abrasion resistance test, coke thermal reactivity test, and coke post-reaction strength test; the coke crush resistance M40, coke abrasion resistance M10, coke thermal reactivity CRI, and coke post-reaction strength CSR of a single type of coal were obtained. Data normalization; vitrinite reflectance R o max The TI, lgMF are normalized, and the normalization equation is: (Equation 4) In the formula: R i - The normalized properties of the i-th single type of coal; r i - Properties of the i-th single type of coal; r max - The maximum value of property r; r min - The minimum value of property r; Draw coke quality control charts, including coke crush strength control chart, coke abrasion resistance control chart, coke thermal reactivity control chart, and coke post-reaction strength control chart; among which: The coke crush resistance control chart is based on the vitrinite reflectance R. o max Using the X-axis as the inert component content TI as the Y-axis and the Gibbs maximum flowability lgMF as the Z-axis, a contour map of coke crush resistance strength M40 is established in a triangular coordinate system. The coke abrasion resistance control chart is based on the vitrinite reflectance R. o max Using the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a contour map of the coke abrasion resistance M10 is established in a triangular coordinate system. The coke thermal reactivity control chart is based on the vitrinite reflectance R. o max Using the X-axis as the inert component content TI as the Y-axis and the Gibbs maximum fluidity lgMF as the Z-axis, a contour map of the coke thermal reactivity CRI is established in a triangular coordinate system. The intensity control chart after coke reaction is based on the vitrinite reflectance R. o max Using the X-axis as the inert component content TI as the Y-axis and the Gibbs free flowability lgMF as the Z-axis, a contour map of the coke reaction strength CSR is established in a triangular coordinate system.

2. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 1), the vitrinite reflectance of a single type of coal, i.e., the average maximum vitrinite reflectance, is specifically tested according to GB / T 6948-2008 "Microscopic Determination of Vitrinite Reflectance of Coal," with no fewer than 100 test points. The mean value μ of the test data is calculated, which is the vitrinite reflectance R. o max .

3. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 2), the contents of vitrinite V, inertinite I, and chitinite E in each type of coal are tested according to GB / T 8899-201 "Methods for Microanalysis and Mineral Determination of Coal".

4. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 3), the maximum Gibbs flowability lgMF of a single type of coal is tested according to GB / T 25213-2010 "Coal Plasticity Constant Torque Gibbs Plasticity Tester Method".

5. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 4), the coke crush resistance strength is tested using a coke oven experiment, as detailed below: A single type of coal coke was prepared using a 40kg coke oven. The crushing strength M40 of the coke was tested using a Micum drum test according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". The coke was sieved by vibrating screen, and the coke with a particle size greater than 60mm was tested by Micum drum test. After 100 revolutions, the coke was allowed to stand for 1-2 minutes. The resulting coke was then sieved by 40mm and weighed. The crush resistance of coke: M40 = m1 / m × 100% (Equation 5) In the formula, m: mass of coke entering the drum, kg; m1: The mass of coke larger than 40mm after exiting the drum, in kg.

6. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 4), the abrasion resistance of coke is tested using a coke oven experiment, as detailed below: A single type of coal coke was prepared using a 40kg coke oven. The abrasion resistance M10 of the coke was tested using a Micum drum test according to GB / T 2006-2008 "Method for Determination of Mechanical Strength of Coke". The coke was sieved by vibrating screen, and the coke with a particle size greater than 60mm was subjected to the Micum drum test. After 100 revolutions, the coke was allowed to stand for 1-2 minutes. The resulting coke was then sieved by 10mm and weighed. Abrasion resistance of coke: M 10 =m2 / m×100% (Equation 6) In the formula, m: mass of coke entering the drum, kg; m2: The mass of coke smaller than 10mm after exiting the drum, in kg.

7. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 4), the thermal reactivity of coke is tested using a coke oven experiment, as detailed below: The thermal reactivity (CRI) of coke was tested according to GB / T 4000-2008 "Test Methods for Reactivity and Post-Reaction Strength of Coke"; 20 kg of coke larger than ø25 mm was crushed and reduced using a jaw crusher to obtain 10 kg; the coke lumps larger than ø25 mm were further crushed and screened using ø25 mm and ø23 mm round hole sieves to produce coke lumps of ø23 to ø25 mm; Weigh 200±0.5g of coke with a diameter of ø25~ø23mm and place it in a high-temperature alloy steel reactor or a corundum reactor. After reacting with carbon dioxide at a flow rate of 5 L / min at 1100℃±5℃ for 2h, the coke reactivity CRI is expressed as the percentage of coke mass loss. CRI = (m³ - m⁴) / m × 100% (Equation 7) In the formula, m3: mass of coke before reaction, g; m4: Mass of residual coke after reaction, in grams.

8. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 4), the strength test of coke after reaction is conducted using a coke oven experiment, as detailed below: The post-reaction strength (CSR) of coke was tested according to GB / T 4000-2008 "Test Method for Reactivity and Post-Reaction Strength of Coke". 20 kg of coke larger than ø25 mm was crushed and reduced using a jaw crusher to obtain 10 kg of coke. The coke lumps larger than ø25 mm were then sieved using ø25 mm and ø23 mm round hole sieves. The coke lumps larger than ø25 mm were then crushed and sieved again to produce coke lumps with a diameter of ø23 to ø25 mm. Weigh 200±0.5g of coke with a particle size of ø23~ø25mm and place it in a high-temperature alloy steel reactor or a corundum reactor. React it with carbon dioxide at a flow rate of 5 L / min at 1100℃±5℃ for 2h. After a Type I drum test, the coke strength CSR after reaction is expressed as the mass fraction of coke with a particle size greater than 10mm in the coke after reaction. CSR = (m5 - m6) / m × 100% (Equation 8) In the formula, m5: mass of residual coke after reaction, g; m6: Mass of coke particles larger than 10mm after drum rotation, in g.

9. The method for predicting coke quality using vitrinite reflectance, inert component content, and Gibbs maximum fluidity of coking coal according to claim 1, characterized in that, In step 6), the data analysis methods used include polynomial regression, inverse distance weighted interpolation, Kriging, minimum curvature method, improved Shepard method, natural neighbor method, nearest neighbor method, radial basis function method, linear interpolation triangular network method, moving average method, and local polynomial method.

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