Method and system for determining the mixing capacity of kr stirrers throughout their service life

Abstract

The application discloses a kind of KR stirring paddle whole service cycle stirring capacity determination method and system, comprising: the appearance of stirring paddle under different service furnace number in current working condition is photographed, and the appearance of stirring paddle picture is obtained;The picture is handled, and the appearance of stirring paddle change characteristic size is determined;Determine the relationship formula of characteristic size with the change of stirring paddle service furnace number, establish the three-dimensional physical model of stirring paddle;According to the three-dimensional physical model of stirring paddle, the molten iron multiphase flow field distribution is calculated;Analysis molten iron multiphase flow field distribution characteristics, obtain molten iron multiphase flow distribution and the relationship formula of change of stirring paddle service furnace number;KR stirring paddle stirring power is calculated under working condition, and the stirring power calculated is used as evaluation index, adjusts and optimizes stirring process parameter.The technical scheme of the application can quantitatively determine the strength of KR stirring paddle stirring capacity in whole service cycle, which can be used as the basis for optimizing process parameters.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of steelmaking in metallurgical industry, and particularly relates to a method and system for judging stirring capacity of KR stirring paddle in whole service cycle. BACKGROUND

[0002] It is very important to reduce the sulfur content in steel as much as possible to meet the mechanical properties of the product. Due to good thermodynamic conditions, desulfurization is usually carried out before the molten iron enters the converter, which is called the molten iron pretreatment process. KR stirring reactor is widely used in the molten iron pretreatment desulfurization in modern steelmaking industry, and its main principle is to promote the kinetics of the desulfurization reaction by mechanical stirring. The size of the stirring paddle has a crucial influence on the flow field of the molten iron in the KR stirring process and the desulfurization rate. Generally, the size change of the stirring paddle during service is related to the refractory material quality of the stirring paddle, the maintenance of the stirring paddle, the slag sticking and slagging frequency of the stirring paddle, the molten iron conditions, the desulfurizer composition, and the desulfurizer addition amount, etc. Its shape will change during use. The size change caused by the wear of the stirring paddle will continuously change the stirring capacity in the whole service cycle, and then affect the desulfurization efficiency and the desulfurization cycle. Therefore, it is of great significance to optimize the process parameters of the stirring paddle in the whole service cycle, improve the desulfurization efficiency and reduce the production cost by accurately judging the stirring capacity of the KR stirring paddle after being used in different number of furnaces. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a method and system for judging the stirring capacity of KR stirring paddle in whole service cycle, which can quantitatively determine the strength of the stirring capacity of the KR stirring paddle in the whole service cycle, and serve as the basis for optimizing the process parameters.

[0004] To achieve the above-mentioned purpose, the present application adopts the following technical solution:

[0005] A method for judging the stirring capacity of KR stirring paddle in whole service cycle, comprising:

[0006] Step S1, taking pictures of the appearance of the stirring paddle after being used in different number of furnaces under the current working condition to obtain the appearance pictures of the stirring paddle;

[0007] Step S2, determining the characteristic size of the appearance change of the stirring paddle according to the appearance pictures of the stirring paddle;

[0008] Step S3, establishing a three-dimensional physical model of the stirring paddle according to the characteristic size of the appearance change of the stirring paddle and through the relationship between the characteristic size and the number of furnaces used by the stirring paddle;

[0009] Step S4, establishing a molten iron multiphase coupling numerical model of the stirring process according to the three-dimensional physical model of the stirring paddle to calculate the distribution of the molten iron multiphase flow field;

[0010] Step S5, according to the molten iron multiphase flow field distribution, determine the molten iron multiphase flow distribution and the change relationship of the stirring paddle used in the furnace number;

[0011] According to step S6, the KR stirring paddle stirring power under the working condition is calculated according to the molten iron multiphase flow distribution and the change relationship of the stirring paddle used in the furnace number, and the calculated stirring power is taken as an evaluation index to adjust and optimize the stirring process parameters.

[0012] As preferred, the characteristic size of the stirring paddle morphology change includes the stirring paddle height, the stirring paddle upper diameter, the stirring paddle lower diameter, the stirring paddle blade width, the stirring paddle upper adhesion height and the stirring paddle lower adhesion height.

[0013] As preferred, the characteristic size change relationship with the stirring paddle used in the furnace number is:

[0014]

[0015] Wherein, C1, C2, C3, C4, K1, K2, K3, K4, K5 and K6 are constants; H 1,initial The stirring paddle height is not used; D 1,initial The stirring paddle upper diameter is not used; D 2,initial The stirring paddle lower diameter is not used; W 1,initial The stirring paddle blade width is not used; N heat The stirring paddle used in the furnace number.

[0016] As preferred, the molten iron multiphase flow distribution and the change relationship of the stirring paddle used in the furnace number are:

[0017]

[0018] Wherein, C6 is a constant; ε is the turbulent energy dissipation rate; n is the rotating speed; N heat The stirring paddle used in the furnace number.

[0019] The present application also provides a KR stirring paddle full service cycle stirring capacity judgment system, comprising:

[0020] The first processing module is used for shooting the stirring paddle morphology after different service life of the stirring paddle under the current working condition, and obtaining the stirring paddle morphology picture;

[0021] The second processing module is used for determining the characteristic size of the stirring paddle morphology change according to the stirring paddle morphology picture;

[0022] The third processing module is used for establishing the stirring paddle three-dimensional physical model through the characteristic size change relationship with the stirring paddle used in the furnace number according to the characteristic size of the stirring paddle morphology change;

[0023] The fourth processing module is used to establish a multiphase coupling numerical model of molten iron during the stirring process based on the three-dimensional physical model of the stirring paddle, and to calculate the multiphase flow field distribution of molten iron.

[0024] The fifth processing module is used to determine the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle, based on the multiphase flow field distribution of molten iron.

[0025] The sixth processing module is used to calculate the stirring power of the KR stirrer under working conditions based on the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirrer. The calculated stirring power is used as an evaluation index to adjust and optimize the stirring process parameters.

[0026] Preferably, the dimensions of the impeller morphology variation characteristics include impeller height, impeller upper diameter, impeller lower diameter, impeller blade width, upper adhesion height of the impeller, and lower adhesion height of the impeller.

[0027] Preferably, the relationship between the characteristic dimension and the number of furnaces using the agitator is as follows:

[0028]

[0029]

[0030] Where C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 are constants; H 1,initial The height of the unused agitator; D 1,initial The diameter of the unused agitator; D 2,initial The diameter of the unused agitator; W 1,initial N represents the width of unused agitator blades. heat Number of furnaces used for the agitator.

[0031] Preferably, the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle is as follows:

[0032]

[0033] Where C6 is a constant; ε is the turbulent kinetic energy dissipation rate; n is the rotational speed; N heat Number of furnaces used for the agitator.

[0034] This invention involves photographing the morphology of the stirring paddle under different heats used in the current operating conditions to obtain images of the stirring paddle morphology; processing the images to determine the characteristic dimensions of the stirring paddle morphology changes; determining the relationship between the characteristic dimensions and the number of heats used by the stirring paddle, and establishing a three-dimensional physical model of the stirring paddle; calculating the multiphase flow field distribution of molten iron based on the three-dimensional physical model of the stirring paddle; analyzing the characteristics of the multiphase flow field distribution of molten iron to obtain the relationship between the multiphase flow distribution of molten iron and the number of heats used by the stirring paddle; calculating the stirring power of the KR stirring paddle under operating conditions, and using the calculated stirring power as an evaluation index to adjust and optimize the stirring process parameters. This invention can quantitatively determine the strength of the stirring capability of the KR stirring paddle throughout its entire service life, and can serve as a basis for optimizing process parameters. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0036] Figure 1 This is a flowchart of the method for determining the stirring capacity of the KR impeller throughout its entire service life according to an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the characteristic dimensions of the agitator impeller after wear in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the multiphase flow field distribution of molten iron in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram showing the multiphase flow distribution of molten iron and the change in the number of furnaces using the stirring paddle in an embodiment of the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] Example 1:

[0043] like Figure 1As shown, this embodiment of the invention provides a method for determining the stirring capacity of a KR impeller throughout its entire service life, including:

[0044] Step S1: Take pictures of the morphology of the stirring paddle under different numbers of furnaces used in the current working conditions to obtain images of the stirring paddle morphology;

[0045] Step S2: Based on the captured images of the impeller morphology, observe the locations where the impeller morphology changes and determine the characteristic dimensions of the impeller morphology changes as impeller height, upper diameter of the impeller, lower diameter of the impeller, width of the impeller blade, upper adhesion height of the impeller, and lower adhesion height of the impeller.

[0046] Step S3: Based on the size distribution of the characteristic dimensions of the agitator morphology under different numbers of furnaces, obtain the relationship between the characteristic dimensions and the number of furnaces. Based on the change in the characteristic dimensions, use 3D modeling software to establish a 3D physical model of the agitator.

[0047] Step S4: Determine the calculation domain of molten iron flow based on the three-dimensional physical model of the stirring paddle, and use the molten iron-air multiphase VOF model and the molten iron flow k-ε model to numerically calculate the molten iron velocity and turbulent kinetic energy distribution, and obtain the multiphase flow field of molten iron under different number of furnaces and rotation speeds of stirring paddles.

[0048] Step S5: Based on the distribution data of molten iron velocity and turbulent kinetic energy under different stirring paddle usage numbers and rotation speeds, fit the relationship between the magnitude of molten iron turbulent kinetic energy and the number of stirring paddles used and the rotation speed.

[0049] According to step S6, based on the relationship between the magnitude of the turbulent kinetic energy of molten iron and the number of furnaces used by the agitator and the change in rotation speed, the magnitude of the turbulent kinetic energy of molten iron when the agitator is used for 1 furnace and at a rotation speed of 90 rpm is obtained. Taking the magnitude of the turbulent kinetic energy of molten iron greater than or equal to the above-mentioned magnitude as the evaluation criterion, the rotation speed of the agitator is adjusted for different numbers of furnaces used by the agitator.

[0050] As one embodiment of the present invention, the dimensions of the stirring impeller morphology variation feature include the stirring impeller height, the upper diameter of the stirring impeller, the lower diameter of the stirring impeller, the width of the stirring impeller blade, the upper adhesion height of the stirring impeller, and the lower adhesion height of the stirring impeller.

[0051] As one embodiment of the present invention, the relationship between the feature size and the number of furnaces using the stirring paddle is expressed as follows:

[0052]

[0053] Where C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 are constants; H 1,initial The height of the unused agitator; D 1,initial The diameter of the unused agitator; D 2,initialThe diameter of the unused agitator; W 1,initial N represents the width of unused agitator blades. heat Number of furnaces used for the agitator.

[0054] Preferably, the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle is as follows:

[0055]

[0056] Where C6 is a constant; ε is the turbulent kinetic energy dissipation rate; n is the rotational speed; N heat Number of furnaces used for the agitator.

[0057] The embodiments of this invention target a stirrer with an initial unused height of 950mm, an initial unused upper diameter of 1350mm, an initial unused lower diameter of 1250mm, and an initial unused blade width of 480mm. The KR stirrer, after use under the current operating conditions, is fixed in place, and its appearance is photographed using a camera to obtain images of the stirrer's morphology for different furnace usage scenarios; for example... Figure 1 As shown, the image is processed, and the characteristic dimensions of the impeller shape change are determined according to the change law of the impeller shape. Based on the change of characteristic dimensions, a three-dimensional physical model of the impeller is established, and the constants C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 in the relationship between the characteristic dimensions and the number of furnaces using the impeller are determined to be -2.615, -3.945, -3.036, -0.926, 0.00516, 0.00506, 0.00533, 0.00078, 34.0, and 17.3, respectively. Figure 2 As shown, a multiphase coupled numerical model of molten iron during the stirring process is established based on the three-dimensional physical model of the agitator, and the multiphase flow field distribution of molten iron is calculated; as follows: Figure 3 As shown, the distribution characteristics of the multiphase flow field of molten iron were determined, and the constant C6 in the formula relating the multiphase flow distribution of molten iron to the number of furnaces using the agitator was found to be 2.3 × 10⁻⁶. -4 Based on the relationship between the multiphase flow distribution of water and the number of furnaces using the agitator, it was calculated that after using 120 furnaces, the stirring power of the KR agitator at a speed of 90 rpm was 0.128 W / kg. Based on this, the stirring process parameters were adjusted and optimized.

[0058] This invention determines the characteristic dimensions of the KR agitator under different numbers of furnaces used, and quantitatively assesses the agitation capacity of the KR agitator throughout its entire service life. Based on the determination criteria of this invention, the agitation process parameters throughout the entire service life of the agitator can be adjusted and optimized according to actual production conditions, serving as the basis for optimizing process parameters.

[0059] Example 2:

[0060] This invention also provides a system for determining the stirring capacity of a KR impeller throughout its entire service life, comprising:

[0061] The first processing module is used to take pictures of the morphology of the stirring paddle after using different numbers of furnaces under the current working conditions, and to obtain images of the stirring paddle morphology.

[0062] The second processing module is used to determine the size of the morphological change characteristics of the impeller based on the impeller morphology image;

[0063] The third processing module is used to establish a three-dimensional physical model of the impeller based on the characteristic dimensions of the impeller shape and the relationship between the characteristic dimensions and the number of furnaces used by the impeller.

[0064] The fourth processing module is used to establish a multiphase coupling numerical model of molten iron during the stirring process based on the three-dimensional physical model of the stirring paddle, and to calculate the multiphase flow field distribution of molten iron.

[0065] The fifth processing module is used to determine the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle, based on the multiphase flow field distribution of molten iron.

[0066] The sixth processing module is used to calculate the stirring power of the KR stirrer under working conditions based on the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirrer. The calculated stirring power is used as an evaluation index to adjust and optimize the stirring process parameters.

[0067] As one embodiment of the present invention, the dimensions of the stirring impeller morphology variation feature include the stirring impeller height, the upper diameter of the stirring impeller, the lower diameter of the stirring impeller, the width of the stirring impeller blade, the upper adhesion height of the stirring impeller, and the lower adhesion height of the stirring impeller.

[0068] As one embodiment of the present invention, the relationship between the feature size and the number of furnaces using the stirring paddle is expressed as follows:

[0069]

[0070] Where C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 are constants; H 1,initial The height of the unused agitator; D 1,initial The diameter of the unused agitator; D 2,initial The diameter of the unused agitator; W 1,initial N represents the width of unused agitator blades. heat Number of furnaces used for the agitator.

[0071] As one embodiment of the present invention, the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle is expressed as follows:

[0072]

[0073] Where C6 is a constant; ε is the turbulent kinetic energy dissipation rate; n is the rotational speed; N heat Number of furnaces used for the agitator.

[0074] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for judging the stirring capacity of a KR impeller throughout its entire service life, characterized in that, include: Step S1: Take pictures of the morphology of the stirring paddle under different numbers of furnaces used in the current working conditions to obtain images of the stirring paddle morphology; Step S2: Determine the characteristic dimensions of the impeller morphology change based on the impeller morphology image; Step S3: Based on the characteristic dimensions of the impeller morphology, and through the relationship between the characteristic dimensions and the number of furnaces used, establish a three-dimensional physical model of the impeller. Step S4: Based on the three-dimensional physical model of the stirring paddle, establish a multiphase coupling numerical model of molten iron during the stirring process, and calculate the multiphase flow field distribution of molten iron. Step S5: Based on the multiphase flow field distribution of molten iron, determine the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle; Step S6: Calculate the stirring power of KR stirring paddle under working conditions based on the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle. Use the calculated stirring power as an evaluation index to adjust and optimize the stirring process parameters. The relationship between the characteristic dimension and the number of furnaces using the agitator is as follows: Where C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 are constants; H 1,initial The height of the unused agitator; D 1,initial The diameter of the unused agitator; D 2,initial The diameter of the unused agitator; W 1,initial N represents the width of unused agitator blades. heat Number of furnaces used for the agitator.

2. The method for determining the stirring capacity of a KR impeller throughout its entire service life as described in claim 1, characterized in that, The dimensions of the impeller morphology variation include impeller height, upper diameter, lower diameter, blade width, upper adhesion height, and lower adhesion height.

3. The method for determining the stirring capacity of a KR impeller throughout its entire service life as described in claim 2, characterized in that, The relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle is as follows: Where C6 is a constant; ε is the turbulent kinetic energy dissipation rate; n is the rotational speed; N heat Number of furnaces used for the agitator.

4. A system for determining the stirring capacity of a KR impeller throughout its entire service life, characterized in that, include: The first processing module is used to take pictures of the morphology of the stirring paddle after using different numbers of furnaces under the current working conditions, and to obtain images of the stirring paddle morphology. The second processing module is used to determine the size of the morphological change characteristics of the impeller based on the impeller morphology image; The third processing module is used to establish a three-dimensional physical model of the impeller based on the characteristic dimensions of the impeller shape and the relationship between the characteristic dimensions and the number of furnaces used by the impeller. The fourth processing module is used to establish a multiphase coupling numerical model of molten iron during the stirring process based on the three-dimensional physical model of the stirring paddle, and to calculate the multiphase flow field distribution of molten iron. The fifth processing module is used to determine the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle, based on the multiphase flow field distribution of molten iron. The sixth processing module is used to calculate the stirring power of the KR stirring paddle under working conditions based on the relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle. The calculated stirring power is used as an evaluation index to adjust and optimize the stirring process parameters. The relationship between the characteristic dimension and the number of furnaces using the agitator is as follows: Where C1, C2, C3, C4, K1, K2, K3, K4, K5, and K6 are constants; H 1,initial The height of the unused agitator; D 1,initial The diameter of the unused agitator; D 2,initial The diameter of the unused agitator; W 1,initial N represents the width of unused agitator blades. heat Number of furnaces used for the agitator.

5. The system for determining the stirring capacity of the KR impeller throughout its entire service life as described in claim 4, characterized in that, The dimensions of the impeller morphology variation include impeller height, upper diameter, lower diameter, blade width, upper adhesion height, and lower adhesion height.

6. The system for determining the stirring capacity of a KR impeller throughout its entire service life as described in claim 5, characterized in that, The relationship between the multiphase flow distribution of molten iron and the number of furnaces using the stirring paddle is as follows: Where C6 is a constant; ε is the turbulent kinetic energy dissipation rate; n is the rotational speed; N heat Number of furnaces used for the agitator.

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