Method and system for characterizing pellet strength indicators based on micro-pore index

Abstract

The application discloses a method and system for characterizing pellet strength indexes based on micro-pore indexes, and the method comprises the following steps: layer-by-layer scanning of a pellet sample to be measured by using an industrial CT to obtain a plurality of pellet slice two-dimensional CT scanning structure images of the pellet sample to be measured; extracting pore-related data based on the pellet slice two-dimensional CT scanning structure images; calculating a pellet pore index based on the extracted pore-related data; and characterizing the pellet strength of the pellet sample to be measured based on the calculated pellet pore index; wherein the greater the pellet pore index, the better the pellet strength, and vice versa. The technical scheme of the application takes the pellet pore index value as a quantitative index to evaluate the compressive strength of the pellet. The method is simple to operate, accurate in result, suitable for popularization and application in steel enterprises and laboratory research, and has a good application prospect.

Description

Technical Field

[0001] This invention relates to the field of strength evaluation technology for blast furnace ironmaking pellets, and particularly to a method and system for characterizing the strength index of pellets based on the micropore index. Background Technology

[0002] With the rapid development of the steel industry, rich ore is becoming increasingly scarce while lean ore is becoming increasingly abundant, leading to rising production costs. Modern blast furnaces aim to produce molten iron on a large scale and at the lowest possible cost. Therefore, the demand for iron-containing furnace charge is increasing, especially for large blast furnaces. Currently, pellets are the main raw material for blast furnace ironmaking. The main charge structure of a blast furnace consists of sinter as the primary component, supplemented with a certain amount of pellets and lump ore. Because the production cost and pollution emissions of pellets are far lower than those of sinter, and because pellets have advantages such as high normal strength, uniform particle size, less powder, high iron content, and good reducibility, their use in blast furnaces is gradually increasing. Therefore, the quality of pellets plays a crucial role in reducing blast furnace energy consumption and increasing blast furnace output.

[0003] Before being fed into the furnace, ore pellets must meet certain compressive strength requirements, and the strength of the pellets is closely related to the distribution of their internal pores. The compressive strength of pellets directly affects the quality of the ore pellets, but currently there is no unified indicator to reflect the compressive strength of ore pellets. Furthermore, the internal structure of pellets is complex; conventional mercury intrusion porosimetry can only detect the overall porosity and cannot obtain data on internal closed pores. Therefore, it is impossible to provide a unified indicator for comparative analysis of the impact of inconsistent pellet sizes and different pore sizes on strength.

[0004] Currently, there is no method to obtain all the pore data inside the pellets, to unify the size of pellets with inconsistent sizes, and there is no indicator to characterize the impact of pellet pores on strength. Summary of the Invention

[0005] This invention provides a method and system for characterizing the strength index of pellets based on micropore index, in order to solve the technical problem that there is currently no method to obtain all the pore data inside the pellets, to unify the size of pellets with inconsistent sizes, and no index in this regard to characterize the influence of pellet pores on strength.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] On one hand, the present invention provides a method for characterizing the strength index of pellets based on the micropore index, the method comprising:

[0008] Industrial CT was used to scan the pellet sample layer by layer to obtain multiple two-dimensional CT scan images of pellet slices of the sample.

[0009] Pore-related data were extracted from two-dimensional CT scan images of pellet slices.

[0010] Based on the extracted pore-related data, the porosity index of the pellets is calculated;

[0011] The strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the pellet strength, and vice versa.

[0012] Furthermore, based on the two-dimensional CT scan structural images of the pellet slices, porosity-related data were extracted, including:

[0013] The multiple two-dimensional CT scan images of the pellet sample to be tested are superimposed layer by layer to obtain the overall three-dimensional CT scan image of the pellet sample to be tested.

[0014] Pore-related data are extracted based on the three-dimensional CT scan structural image; wherein, the pore-related data includes: pore volume, pore surface area, and pore three-dimensional scan coordinate data.

[0015] Furthermore, the calculation of the pellet porosity index based on the extracted pore-related data includes:

[0016] Based on the three-dimensional CT scan structural image, the distance of each pore from the CT scan center point is calculated according to the three-dimensional scan coordinate data of each pore. Then, the closest distance d from the CT scan center point among all pores is obtained. 最近 And the farthest distance d from the center point of the CT scan among all pores 最远 ;

[0017] Calculate the sphere radius of the pellet sample to be tested.

[0018] The volume V of the pellet sample to be tested is calculated based on the sphere radius r of the pellet sample to be tested.

[0019] The pore diameter of each pore is calculated based on the pore volume and surface area.

[0020] The number M of pores with a diameter smaller than a preset threshold is counted.

[0021] Calculate the porosity index of the pellets

[0022] Furthermore, the step of counting the number of pores with a diameter smaller than a preset threshold includes:

[0023] Based on the pore size, the pores of different pellets are classified into micropores, mesopores, and macropores; wherein, micropores refer to pores with a pore size of less than 20 μm, mesopores refer to pores with a pore size in the range of 20 to 60 μm, and macropores refer to pores with a pore size of more than 60 μm.

[0024] The number of micropores, mesopores, and macropores in the pellet sample to be tested are counted; where, when calculating the pellet porosity index P, the number of pores with a pore size smaller than a preset threshold refers to the number of micropores.

[0025] On the other hand, the present invention also provides a system for characterizing the strength index of pellets based on the micropore index, the system comprising:

[0026] The scanning module is used to perform layer-by-layer scanning of the pellet sample under test using industrial CT to obtain multiple two-dimensional CT scan structural images of pellet slices of the pellet sample under test.

[0027] The data processing module is used for:

[0028] Pore-related data were extracted from two-dimensional CT scan images of pellet slices.

[0029] Based on the extracted pore-related data, the porosity index of the pellets is calculated;

[0030] The strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the pellet strength, and vice versa.

[0031] Furthermore, based on the two-dimensional CT scan structural images of the pellet slices, porosity-related data were extracted, including:

[0032] The multiple two-dimensional CT scan images of the pellet sample to be tested are superimposed layer by layer to obtain the overall three-dimensional CT scan image of the pellet sample to be tested.

[0033] Pore-related data are extracted based on the three-dimensional CT scan structural image; wherein, the pore-related data includes: pore volume, pore surface area, and pore three-dimensional scan coordinate data.

[0034] Furthermore, the calculation of the pellet porosity index based on the extracted pore-related data includes:

[0035] Based on the three-dimensional CT scan structural image, the distance of each pore from the CT scan center point is calculated according to the three-dimensional scan coordinate data of each pore. Then, the closest distance d from the CT scan center point among all pores is obtained. 最近And the farthest distance d from the center point of the CT scan among all pores 最远 ;

[0036] Calculate the sphere radius of the pellet sample to be tested.

[0037] The volume V of the pellet sample to be tested is calculated based on the sphere radius r of the pellet sample to be tested.

[0038] The pore diameter of each pore is calculated based on the pore volume and surface area.

[0039] The number M of pores with a diameter smaller than a preset threshold is counted.

[0040] Calculate the porosity index of the pellets

[0041] Furthermore, the step of counting the number of pores with a diameter smaller than a preset threshold includes:

[0042] Based on the pore size, the pores of different pellets are classified into micropores, mesopores, and macropores; wherein, micropores refer to pores with a pore size of less than 20 μm, mesopores refer to pores with a pore size in the range of 20 to 60 μm, and macropores refer to pores with a pore size of more than 60 μm.

[0043] The number of micropores, mesopores, and macropores in the pellet sample to be tested are counted; where, when calculating the pellet porosity index P, the number of pores with a pore size smaller than a preset threshold refers to the number of micropores.

[0044] The beneficial effects of the technical solution provided by this invention include at least the following:

[0045] This invention employs industrial CT scanning technology for non-destructive testing, overcoming the limitation of traditional mercury intrusion porosimetry (MIP) methods in detecting pellet porosity by failing to obtain data on internally sealed pores. It directly characterizes the size and pore distribution of pellets of varying sizes, thereby evaluating the impact of different pellet pore distributions on the compressive strength of the pellet ore. This invention solves the problem of existing technologies being unable to characterize the influence of internal pores on strength, and provides a quantitative index for evaluating the compressive strength of different pellets' pores, filling a gap in current testing and evaluation of the impact of internal pores on pellet strength. Furthermore, this invention can simultaneously scan multiple pellets of varying sizes, enabling more time-efficient and accurate representation of different pellet pore distributions, providing a new approach and method for pellet quality evaluation systems. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of the execution flow of the method for characterizing the strength index of pellets based on the micropore index provided in the embodiments of the present invention;

[0048] Figure 2 This is a graph showing the relationship between the porosity index of O1 and O2 spheres and their compressive strength.

[0049] Figure 3 This is a graph showing the relationship between the porosity index of O3 to O5 pellets and their compressive strength. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0051] First Embodiment

[0052] This embodiment provides a method for characterizing the strength index of pellets based on the micropore index. This method can be implemented by electronic equipment, and the execution flow of the method is as follows: Figure 1 As shown, it includes the following steps:

[0053] S1. Industrial CT is used to scan the pellet sample under test layer by layer to obtain multiple two-dimensional CT scan images of pellet slices of the pellet sample under test.

[0054] Specifically, in this embodiment, the implementation process of S1 is as follows:

[0055] S11, configure parameters for the industrial CT;

[0056] S12, using an industrial CT scanner with the parameters set, the test pellet sample is scanned layer by layer to obtain N CT scan structural images of the test pellet sample slices.

[0057] S2, based on the two-dimensional CT scan structural image of the pellet slice, extract the porosity-related data;

[0058] Specifically, in this embodiment, the implementation process of S2 is as follows: multiple two-dimensional CT scan images of the pellet sample to be tested are superimposed layer by layer to obtain the overall three-dimensional CT scan image of the pellet sample to be tested; based on the three-dimensional CT scan image, the pore-related data are extracted from the CT scan image of the pellet pores to obtain the pore volume, pore surface area, and three-dimensional scan data x, y, z of the pellet sample to be tested.

[0059] S3, Calculate the porosity index of the pellets based on the extracted pore-related data;

[0060] Specifically, in this embodiment, the implementation process of S3 is as follows:

[0061] S31, take the x, y, and z values ​​of different pores in the pellet to obtain the distance from the pore to the center point of the CT scan in the pellet to be tested. Then, the nearest distance d from the center point of the CT scan in all pores is obtained. 最近 And the farthest distance d from the center point of the CT scan among all pores 最远 ;

[0062] S32, calculate the radius of the sphere in the pellet sample to be tested.

[0063] S33, Calculate the volume of the pellet sample to be tested based on the sphere radius r of the sample.

[0064] S34, based on the volume V of the pores 孔 and surface area S 孔 The pore diameter of each pore was calculated.

[0065] S35, based on the pore size, the pores of different pellets are classified into micropores (pore size < 20 μm), mesopores (pore size between 20 and 60 μm), and macropores (pore size > 60 μm), thus obtaining the number of micropores, mesopores, and macropores in the sample, denoted as M. ＜20um M 20～60um M ＞60um .

[0066] S36, calculate the porosity index of the pellets.

[0067] S4, the strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the compressive strength performance of the pellet, and vice versa.

[0068] Specifically, in this embodiment, the implementation process of S4 is as follows:

[0069] S41, to obtain the porosity index and compressive strength of different pellets;

[0070] S42. Based on the compressive strength values ​​measured for different pellets, the porosity index values ​​of the pellets are analyzed and evaluated. The compressive strength of the pellets corresponding to the porosity index values ​​is obtained. By combining the analysis of the pellet porosity index values ​​and compressive strength, the index is evaluated, and the relationship between the pellet porosity index and compressive strength is obtained.

[0071] Among them, such as Figure 2 and Figure 3 As shown, the method in this embodiment, by comparing the unit volume porosity corresponding to the micropores of different pellets, obtains a unified measurement index, the pellet porosity index, which allows for a more in-depth evaluation of the impact of the pore distribution of different pellets on the compressive strength of the pellet ore. The specific implementation process is as follows:

[0072] The test pellets O1-O5 were selected, where O1 and O2 were acidic pellets, and O3-O5 were alkaline pellets. Industrial CT was used to scan the pellet samples O1-O5 layer by layer, obtaining N CT scan images of the pellet slices. Pore-related data, such as pore volume, pore surface area, and three-dimensional pore data (x, y, z), were extracted from each pellet pore CT scan image. Several pore CT scan images were then layer-by-layer superimposed to obtain a complete three-dimensional CT scan image.

[0073] Then, take the x1, y1, and z1 values ​​of the pores in the O1 pellet to obtain the distance from the pores in the pellet to be tested to the center point of the CT scan. Then, the closest value d from the center point of the CT scan. 最近 And the farthest value d 最远 ,pass The radius r of the sphere O1 to be tested is obtained. O1 =9.687.

[0074] Then, based on the radius r of sphere O1 O1 ,pass Calculate the volume V of the sphere. O1 =3806.09. Then, by statistically analyzing the pore volume V1 and pore surface area S1 of sphere O1, the pore diameter value is obtained. Based on the pore size, the pores of the O1 spheres are classified into micropores (<20µm), mesopores (20–60µm), and macropores (>60µm), thus obtaining the number of micropores, mesopores, and macropores (M) in the O1 spheres. ＜20um M 20～60um M ＞60um The values ​​are 217519, 165120, and 1487 respectively. Then, the volume V of sphere O1 is calculated. O1 The average number of micropores M ＜20um,pass The porosity per unit volume of sphere O1 was found to be P1 = 57.15, completing one set of treatments.

[0075] Repeat the above steps to obtain the porosity P per unit volume of the O2-O5 spheres. i Values: P2 = 67.56, P3 = 51.05, P4 = 68.53, P5 = 85.74, completing 4 sets of processing.

[0076] Based on the compressive strength values ​​measured for acidic spheres O1-O2 and basic spheres O3-O5, the porosity index P of the pellets was then calculated. i The value was analyzed and evaluated. The porosity index P of the pellets was obtained. i The value corresponds to the compressive strength of the pellet, such as Figure 2 and Figure 3 As shown, the influence of the pore distribution of different pellets on compressive strength is quantitatively evaluated based on the obtained processing results. Finally, the porosity P per unit volume corresponding to the micropores of the pellets is obtained. i The higher the value, the better the compressive strength of the pellets, and vice versa.

[0077] It is worth mentioning that, to increase the objectivity of the calculation of the porosity index P of the pellets, another calculation method can be used, specifically: 1. Calculate the number of micropores per unit volume. 2. Calculate the proportion of micropores in all pores. 3. Calculate the porosity index of the pores. in, Let be the pore size of the i-th micropore. Let be the diameter of the i-th central hole. 4. The porosity index of the pellet is obtained by weighted summing of the above parameters, i.e.: Wherein, λ1, λ2, and λ3 are all preset weight values, and in this embodiment, their values ​​are 0.5, 0.3, and 0.2, respectively.

[0078] In summary, this embodiment employs industrial CT scanning technology for non-destructive testing, overcoming the limitation of traditional mercury intrusion porosimetry in detecting pellet porosity by failing to obtain data on internally sealed pores. It directly characterizes the size and pore distribution of pellets of varying sizes, thereby evaluating the impact of different pellet pore distributions on the compressive strength of the pellet ore. This solves the problem of existing technologies being unable to characterize the influence of internal pores on strength, and provides a quantitative index for evaluating the compressive strength of different pellets' pores, filling a gap in current testing and evaluation of the impact of internal pores on pellet strength. Furthermore, it can simultaneously scan multiple pellets of varying sizes, providing a more time-efficient and accurate representation of different pellet pore distributions, offering a new approach and method for pellet quality evaluation systems.

[0079] Second Embodiment

[0080] This embodiment provides a system for characterizing the strength index of pellets based on the micropore index. The system includes the following modules:

[0081] The scanning module is used to perform layer-by-layer scanning of the pellet sample under test using industrial CT to obtain multiple two-dimensional CT scan structural images of pellet slices of the pellet sample under test.

[0082] The data processing module is used for:

[0083] Pore-related data were extracted from two-dimensional CT scan images of pellet slices.

[0084] Based on the extracted pore-related data, the porosity index of the pellets is calculated;

[0085] The strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the pellet strength, and vice versa.

[0086] The system for characterizing pellet strength based on micropore index in this embodiment corresponds to the method for characterizing pellet strength based on micropore index in the first embodiment described above. The functions implemented by each module in the system for characterizing pellet strength based on micropore index in this embodiment correspond one-to-one with the process steps in the method for characterizing pellet strength based on micropore index in the first embodiment described above; therefore, they will not be repeated here.

[0087] Furthermore, it should be noted that the present invention can be provided as a method, apparatus, or computer program product. Therefore, embodiments of the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code.

[0088] Embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0089] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing terminal equipment to cause a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0090] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0091] Finally, it should be noted that the above description represents a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A method for characterizing the strength index of pellets based on micropore index, characterized in that, include: Industrial CT was used to scan the pellet sample layer by layer to obtain multiple two-dimensional CT scan images of pellet slices of the sample. Pore-related data were extracted from two-dimensional CT scan images of pellet slices. Based on the extracted pore-related data, the porosity index of the pellets is calculated; The strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the pellet strength, and vice versa. Based on the two-dimensional CT scan images of the pellet slices, porosity-related data were extracted, including: The multiple two-dimensional CT scan images of the pellet sample to be tested are superimposed layer by layer to obtain the overall three-dimensional CT scan image of the pellet sample to be tested. Pore-related data were extracted from the three-dimensional CT scan structural image; The calculation of the pellet porosity index based on the extracted pore-related data includes: Based on the three-dimensional CT scan structural image, the distance of each pore from the CT scan center point is calculated according to the three-dimensional scan coordinate data of each pore. Then, the shortest distance from the CT scan center point among all pores is obtained. And the farthest distance from the center point of the CT scan among all pores ; Calculate the sphere radius of the pellet sample to be tested. ; Based on the sphere radius of the pellet sample to be tested The volume of the pellet sample to be tested was calculated. V ; The pore diameter of each pore is calculated based on the pore volume and surface area. Count the number of pores with a diameter smaller than a preset threshold. M ; Calculate the porosity index of the pellets .

2. The method for characterizing the strength index of pellets based on micropore index as described in claim 1, characterized in that, The pore-related data includes: pore volume, pore surface area, and pore three-dimensional scan coordinate data.

3. The method for characterizing the strength index of pellets based on micropore index as described in claim 1, characterized in that, The method of counting the number of pores with a diameter smaller than a preset threshold includes: Based on the pore size, the pores of different pellets are classified into micropores, mesopores, and macropores; wherein, micropores refer to pores with a pore size of less than 20 μm, mesopores refer to pores with a pore size in the range of 20 to 60 μm, and macropores refer to pores with a pore size of more than 60 μm. The number of micropores, mesopores, and macropores in the pellet sample to be tested were statistically determined; among them, the porosity index of the pellets was calculated. When the pore size is smaller than the preset threshold, the number of pores refers to the number of micropores.

4. A system for characterizing the strength index of pellets based on micropore index, characterized in that, include: The scanning module is used to perform layer-by-layer scanning of the pellet sample under test using industrial CT to obtain multiple two-dimensional CT scan structural images of pellet slices of the pellet sample under test. The data processing module is used for: Pore-related data were extracted from two-dimensional CT scan images of pellet slices. Based on the extracted pore-related data, the porosity index of the pellets is calculated; The strength of the pellet sample is characterized by the calculated pellet porosity index; wherein, the larger the pellet porosity index, the better the pellet strength, and vice versa. Based on the two-dimensional CT scan images of the pellet slices, porosity-related data were extracted, including: The multiple two-dimensional CT scan images of the pellet sample to be tested are superimposed layer by layer to obtain the overall three-dimensional CT scan image of the pellet sample to be tested. Pore-related data were extracted from the three-dimensional CT scan structural image; The calculation of the pellet porosity index based on the extracted pore-related data includes: Based on the three-dimensional CT scan structural image, the distance of each pore from the CT scan center point is calculated according to the three-dimensional scan coordinate data of each pore. Then, the shortest distance from the CT scan center point among all pores is obtained. And the farthest distance from the center point of the CT scan among all pores ; Calculate the sphere radius of the pellet sample to be tested. ; Based on the sphere radius of the pellet sample to be tested The volume of the pellet sample to be tested was calculated. V ; The pore diameter of each pore is calculated based on the pore volume and surface area. Count the number of pores with a diameter smaller than a preset threshold. M ; Calculate the porosity index of the pellets .

5. The system for characterizing the strength index of pellets based on micropore index as described in claim 4, characterized in that, The pore-related data includes: pore volume, pore surface area, and pore three-dimensional scan coordinate data.

6. The system for characterizing the strength index of pellets based on micropore index as described in claim 4, characterized in that, The method of counting the number of pores with a diameter smaller than a preset threshold includes: Based on the pore size, the pores of different pellets are classified into micropores, mesopores, and macropores; wherein, micropores refer to pores with a pore size of less than 20 μm, mesopores refer to pores with a pore size in the range of 20 to 60 μm, and macropores refer to pores with a pore size of more than 60 μm. The number of micropores, mesopores, and macropores in the pellet sample to be tested were statistically determined; among them, the porosity index of the pellets was calculated. When the pore size is smaller than the preset threshold, the number of pores refers to the number of micropores.

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