A quenching and tempering method for a vanadium-containing pig iron purification and tempering device

Abstract

The present invention relates to a converter, and provides a quenching and tempering method for a vanadium-containing pig iron purification quenching and tempering device, comprising a furnace body, a plurality of air inlet holes opened at the bottom of the furnace body, and a bottom blowing device arranged below the furnace body; the bottom blowing device comprises a base, a plurality of air blowing devices arranged on the base, and an air supply device connected to the air blowing device; the air blowing device comprises a sleeve with an upper opening connected to the air supply device, and a nozzle detachably connected to the sleeve; the nozzle is detachably inserted in the air inlet hole. The quenching and tempering method for the vanadium-containing pig iron purification quenching and tempering device of the present invention can more efficiently perform vanadium extraction from converter bottom blowing pig iron.

Description

Technical Field

[0001] The invention relates to the technical field of converters, and in particular to a tempering method of a vanadium-containing pig iron purification and tempering device. Background Art

[0002] The hot metal pretreatment process of oxidizing vanadium in hot metal into vanadium slag and separating it from the hot metal is called pyrometallurgical vanadium extraction. Generally, no slag-making agent is added, and only air or oxygen is blown into the hot metal to oxidize the vanadium in it. The generated V2O5 enters the slag phase together with the oxides of other easily oxidizable elements such as Si, Ti, and Mn in the hot metal, and a usable vanadium slag is obtained.

[0003] The vanadium extraction process is generally carried out in a converter. Molten iron is poured into the converter, and then oxygen is blown in to oxidize the vanadium. However, the fluidity of the molten iron is poor, and it is difficult to fully stir the molten iron by blowing oxygen alone, which makes the oxidation efficiency of vanadium low. Therefore, bottom blowing is usually performed at the bottom of the converter, that is, gas (usually inert gas) is introduced into the bottom of the converter to stir the molten iron, so that the molten iron and oxygen are fully mixed and then fully oxidized. However, in the actual production process, the addition of bottom blowing gas is limited. First, the temperature of the molten iron is high, so if the temperature of the gas blown in is low, the molten iron will be cooled, affecting the oxidation efficiency. Secondly, if too much bottom blowing gas is added, the bottom blowing gas will take away some oxygen during the rising process, thereby affecting the oxidation efficiency, and the insufficient flow rate of the bottom blowing gas will affect the stirring efficiency. Secondly, since the bottom blowing structure is added to the bottom of the converter, its structure is more complicated, and the current bottom blowing structure is usually integrated with the converter, so it is very inconvenient to overhaul, maintain and replace, which seriously affects the service life of the converter. In summary, a converter with a simpler and more reliable structure and higher bottom blowing efficiency can be designed for the vanadium extraction process from pig iron. Summary of the invention

[0004] The object of the present invention is to provide a quenching and tempering method for a vanadium-containing pig iron purification and tempering device, which can more efficiently carry out vanadium extraction from converter bottom blowing pig iron.

[0005] The embodiments of the present invention are realized by the following technical scheme: the vanadium-containing pig iron purification and tempering device of the present invention comprises a furnace body, a plurality of air inlet holes opened at the bottom of the furnace body, and a bottom blowing device arranged below the furnace body; the bottom blowing device comprises a base, a plurality of air blowing devices arranged on the base, and an air supply device connected to the air blowing device; the air blowing device comprises a sleeve with an upper end opening connected to the air supply device, and a nozzle detachably connected to the sleeve; the nozzle is detachably inserted into the air inlet hole.

[0006] Furthermore, the air inlet holes are distributed along the circumferential direction of the bottom of the furnace body; and the distances between the plurality of air inlet holes and the axis of the furnace body are all different.

[0007] Furthermore, an air passage is provided inside the nozzle, the upper end of the air passage is arranged through the upper end of the nozzle, and the lower end of the air passage is arranged on the side wall of the nozzle; the upper end of the air passage is oriented obliquely upward.

[0008] Furthermore, the projection of the direction of the upper end of the air passage on the horizontal plane is parallel to the tangent direction of the circumference of the furnace body at the nozzle.

[0009] Furthermore, the air supply device includes an air source and an air pipe connected to the air outlet end of the air source; the air pipe passes through the side wall of the sleeve and is connected to the lower end of the airway.

[0010] Furthermore, a pair of the air passages are provided in the nozzle, the pair of the air passages are respectively provided on the opposite sides of the nozzle and are symmetrically arranged, a sleeve is connected to a pair of the air pipes, the pair of the air pipes are respectively provided on the opposite sides of the sleeve, and a sleeve is communicated with an air passage.

[0011] Furthermore, a straight-line limiting head is provided at the lower end of the nozzle, and a straight-line limiting groove is provided on the inner bottom wall of the sleeve; the limiting head is clamped in the limiting groove, and the pair of air pipes are located at the same height.

[0012] Furthermore, the upper end of the sleeve is provided with a trumpet-shaped opening; the lower end of the air inlet hole is provided with a trumpet-shaped opening.

[0013] Furthermore, a spring is provided between the sleeve and the base.

[0014] The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device comprises the following steps:

[0015] (1) Push the base to the bottom of the furnace body, and then slowly lower the furnace body so that the nozzle is inserted into the air inlet;

[0016] (2) Pour molten iron into the furnace body and extend the oxygen blowing pipe into the furnace body;

[0017] (3) The nitrogen in the gas source is sprayed into the molten iron in the furnace body through the gas pipe and the gas channel, and the nozzles are marked as A, B, C, and D in the clockwise direction, the gas channels facing the clockwise direction are marked as A1, B1, C1, and D1, and the gas channels facing the counterclockwise direction are marked as A2, B2, C2, and D2;

[0018] (4) The air flow intensity is: when the bottom blowing device starts to operate, A2, B2, C1, and D2 are closed, D1>A1>B1>C2, and the oxygen blowing pipe is moved to the top of the nozzle D;

[0019] After 30-60s, A2, B2, C2, and D1 are closed, A1>B1>C1>D2, and the oxygen blowing tube is moved to the top of nozzle A;

[0020] After 30-60s, A1, B2, C2, and D2 are closed, B1>C1>D1>A2, and the oxygen blowing tube is moved to the top of nozzle B;

[0021] After 30-60s, A2, B1, C2, and D2 are closed, C1>D1>A1>B2, and the oxygen blowing tube is moved to the top of nozzle C;

[0022] (5) Repeat step (4) until the vanadium in the molten iron is fully converted into iron slag, and then discharge the iron slag and molten iron.

[0023] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects: the tempering method of the vanadium-containing pig iron purification and tempering device of the present invention can be used to move the bottom blowing device to the bottom of the furnace body through the driving device, and then move the position of the furnace body to insert the nozzle into the air inlet for jetting, and stir the molten iron by spraying inert gas, so that the molten iron is fully in contact with oxygen, and the vanadium in the molten iron is oxidized to form slag. In this process, the size of the jet flow of the nozzle can be cyclically adjusted to promote the molten iron to not only roll in a local range, but also to be in a state of slow flow as a whole, so that the molten iron can be stirred more fully. In this process, the nozzle is heated and expanded by the action of the high-temperature inert gas and the molten iron, and then can be stuck in the air inlet. When the purification is completed, the furnace body can be directly lifted, so that the nozzle is directly pulled out of the sleeve, and then the furnace body can be turned over to pour out the slag and molten iron, and then the furnace body can be lowered again and the nozzle can be reinserted into the sleeve. The whole process can not only effectively reduce the jet flow rate while ensuring the molten iron stirring efficiency, but also make the lower side of the furnace body more convenient for maintenance, inspection and replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic structural diagram of a device for purifying and tempering vanadium-containing pig iron from one perspective provided in an embodiment of the present invention;

[0026] Figure 2 A schematic structural diagram of a vanadium-containing pig iron purification and tempering device from two perspectives provided in an embodiment of the present invention;

[0027] Figure 3A schematic structural diagram of a vanadium-containing pig iron purification and tempering device from three perspectives provided in an embodiment of the present invention;

[0028] Figure 4 For along Figure 3 Partial cross-sectional view along the AA direction;

[0029] Figure 5 A schematic diagram of the structure of a bottom blowing device provided in an embodiment of the present invention;

[0030] Figure 6 A schematic diagram of the structure of a nozzle portion provided by an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of the structure inside the nozzle provided in an embodiment of the present invention.

[0032] Icons: 11-furnace body, 12-air inlet, 21-base, 22-sleeve, 23-air pipe, 24-spring, 25-nozzle, 26-air duct. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Example 1

[0039] The following is further described in conjunction with specific embodiments. Figure 1 -Attached Figure 7 As shown in the figure (only the lower part of the furnace body 11 is shown in the figure), the vanadium-containing pig iron purification and tempering device of this embodiment includes a furnace body 11, a plurality of air inlet holes 12 opened at the bottom of the furnace body 11, and a bottom blowing device arranged below the furnace body 11; the bottom blowing device includes a base 21, a plurality of air blowing devices arranged on the base 21, and an air supply device connected to the air blowing device; the air blowing device includes a sleeve 22 with an upper end opening connected to the air supply device, and a nozzle 25 detachably connected to the sleeve 22; the nozzle 25 is detachably inserted in the air inlet hole 12. Specifically, the furnace body 11 can be a traditional converter structure. When in use, the bottom blowing device can be moved to the bottom of the furnace body 11 by the driving device, and then the position of the furnace body 11 can be moved to insert the nozzle 25 into the air inlet 12 for jetting. The molten iron is stirred by spraying inert gas, so that the molten iron is fully in contact with oxygen, and the vanadium in the molten iron is oxidized to form slag. In this process, the size of the jet flow rate of the nozzle 25 can be cyclically adjusted to cause the molten iron to not only roll in a local range, but also to flow slowly as a whole, so that the molten iron can be stirred more fully. In this process, the nozzle 25 is heated and expanded by the high-temperature inert gas and the molten iron, and then can be stuck in the air inlet 12. After the purification is completed, the furnace body 11 can be directly lifted, so that the nozzle 25 is directly pulled out from the sleeve 22, and then the furnace body 11 can be turned over to pour out the slag and molten iron, and then the furnace body 11 can be lowered again and the nozzle 25 can be reinserted into the sleeve 22. The whole process can not only effectively reduce the flow rate of the jet while ensuring the stirring efficiency of the molten iron, but also make the lower side of the furnace body 11 more convenient for maintenance, overhaul and replacement.

[0040] The air inlet holes 12 in this embodiment are distributed along the circumferential direction of the bottom of the furnace body 11; the distances between the multiple air inlet holes 12 and the axis of the furnace body 11 are all different. Specifically, this can not only stir the molten iron in the circumferential direction, but also stir the molten iron in the radial direction.

[0041] In this embodiment, the nozzle 25 is provided with an air passage 26, the upper end of the air passage 26 is arranged through the upper end of the nozzle 25, and the lower end of the air passage 26 is arranged on the side wall of the nozzle 25; the upper end of the air passage 26 is oriented obliquely upward. The projection of the upper end of the air passage 26 on the horizontal plane is parallel to the tangent direction of the circumference of the furnace body 11 at the nozzle 25. Specifically, this can push the molten iron to make a circular circulation motion.

[0042] The air supply device in this embodiment includes an air source and an air pipe 23 connected to the air outlet of the air source; the air pipe 23 passes through the side wall of the sleeve 22 and is connected to the lower end of the air channel 26. A pair of air channels 26 are provided in a nozzle 25, and the pair of air channels 26 are respectively arranged on the opposite sides of the nozzle 25 and are symmetrically arranged. A sleeve 22 is connected with a pair of air pipes 23, and the pair of air pipes 23 are respectively arranged on the opposite sides of the sleeve 22, and the sleeve 22 is connected with an air channel 26. Specifically, each air pipe 23 and air nozzle has an independent air supply, and the air flow size of the air channel 26 on the circumference of the same direction can be increased or decreased in sequence, so that a larger turbulence can be generated in a local range, and then the turbulence is pushed to make a circular motion to achieve better stirring and mixing.

[0043] In this embodiment, a straight-line stopper is provided at the lower end of the nozzle 25, and a straight-line stopper groove is provided on the inner bottom wall of the sleeve 22; the stopper groove is clamped in the stopper groove, and the pair of air pipes 23 are located at the same height. Specifically, after the nozzle 25 is inserted into the sleeve 22, the positioning can be directly achieved, and the air pipe 23 is more conveniently connected to the air passage 26, and since the pair of air passages 26 are in an identical symmetrical relationship, the direction of the airflow will not be affected.

[0044] The upper end of the sleeve 22 in this embodiment is provided with a trumpet-shaped opening; the lower end of the air inlet 12 is provided with a trumpet-shaped opening. A spring 24 is provided between the sleeve 22 and the base 21. Specifically, the trumpet-shaped opening is for better insertion. It should be noted that the nozzle 25 can be provided with a two-stage structure with a small upper part and a large lower part, so that it can not only be better inserted into the air inlet 12, but the nozzle 25 itself also has a higher strength. The air inlet 12 needs to be designed into a shape that matches the nozzle 25 to improve the sealing performance; the spring 24 is provided between the sleeve 22 and the base 21 in order to better push the nozzle 25 into the air inlet 12.

[0045] Example 2

[0046] This embodiment provides a quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device based on Embodiment 1, comprising the following steps:

[0047] (1) Push the base 21 to the bottom of the furnace body 11, and then slowly lower the furnace body 11 so that the nozzle 25 is inserted into the air inlet 12;

[0048] (2) Pour molten iron into the furnace body 11, and extend the oxygen blowing pipe into the furnace body 11;

[0049] (3) The nitrogen in the gas source is sprayed into the molten iron in the furnace body 11 through the gas pipe 23 and the gas channel 26, and the nozzles 25 are marked as A, B, C, and D in the clockwise direction, and the gas channels 26 facing the clockwise direction are marked as A1, B1, C1, and D1 respectively, and the gas channels 26 facing the counterclockwise direction are marked as A2, B2, C2, and D2 respectively;

[0050] (4) The air flow intensity is: when the bottom blowing device starts to operate, A2, B2, C1, and D2 are closed, D1>A1>B1>C2, and the oxygen blowing pipe is moved to the top of the nozzle 25D;

[0051] After 60 seconds, A2, B2, C2, and D1 are closed, A1>B1>C1>D2, and the oxygen blowing tube is moved to just above the nozzle 25A;

[0052] After 60s, A1, B2, C2, and D2 are closed, B1>C1>D1>A2, and the oxygen blowing tube is moved to just above the nozzle 25B;

[0053] After 60 seconds, A2, B1, C2, and D2 are closed, C1>D1>A1>B2, and the oxygen blowing tube is moved to just above the nozzle 25C;

[0054] (5) Repeat step (4) until the vanadium in the molten iron is fully converted into iron slag, and then discharge the iron slag and molten iron.

[0055] In this embodiment, four air inlets 12 are provided, wherein the air passage 26 in each air inlet 12 does not flow in a clockwise direction, and the gas discharged from the air passage 26 in front of the air passage 26 with the largest air flow (clockwise) is directed in a counterclockwise direction. Although the air flow discharged in the counterclockwise direction is the smallest, it can better disturb the rapidly advancing turbulent group and achieve more efficient and uniform disturbance. In addition, an oxygen blowing pipe is provided above the air inlet 12 with the largest air flow because the molten iron here has the largest tumbling rate, and oxygen blowing at this time can achieve a more efficient oxidation reaction.

[0056] In summary, the tempering method of the vanadium-containing pig iron purification and tempering device of this embodiment can be used to move the bottom blowing device to the bottom of the furnace body 11 through the driving device when in use, and then move the position of the furnace body 11 to insert the nozzle 25 into the air inlet 12 for jetting, and stir the molten iron by spraying inert gas, so that the molten iron is fully in contact with oxygen, and the vanadium in the molten iron is oxidized into slag. In this process, the size of the jet flow rate of the nozzle 25 can be cyclically adjusted to promote the molten iron to not only roll in a local range, but also to be in a state of slow flow as a whole, so that the molten iron can be stirred more fully. In this process, the nozzle 25 is heated and expanded by the action of the high-temperature inert gas and the molten iron, and then can be stuck in the air inlet 12. When the purification is completed, the furnace body 11 can be directly lifted, so that the nozzle 25 is directly pulled out from the sleeve 22, and then the furnace body 11 can be turned over to pour out the slag and molten iron, and then the furnace body 11 can be lowered again, and the nozzle 25 can be reinserted into the sleeve 22. The whole process can not only effectively reduce the flow rate of the jet while ensuring the stirring efficiency of the molten iron, but also make the lower side of the furnace body 11 more convenient for maintenance, overhaul and replacement.

[0057] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A quenching and tempering method for a vanadium-containing pig iron purification quenching and tempering device, characterized in that: The invention comprises a furnace body (11), a plurality of air inlet holes (12) opened at the bottom of the furnace body (11), and a bottom blowing device arranged below the furnace body (11); the bottom blowing device comprises a base (21), a plurality of air blowing devices arranged on the base (21), and an air supply device connected to the air blowing device; the air blowing device comprises a sleeve (22) with an upper end opening connected to the air supply device, and a nozzle (25) detachably connected to the sleeve (22); the nozzle (25) is detachably inserted into the air inlet hole (12); an air duct (26) is arranged inside the nozzle (25), the upper end of the air duct (26) passes through the upper end of the nozzle (25), and the air duct (26) is arranged The lower end of the air passage (26) is arranged on the side wall of the nozzle (25); the upper end of the air passage (26) is oriented obliquely upward; the air supply device comprises an air source and an air pipe (23) connected to the air outlet end of the air source; the air pipe (23) passes through the side wall of the sleeve (22) and is communicated with the lower end of the air passage (26); a pair of air passages (26) is arranged in one nozzle (25), the pair of air passages (26) are respectively arranged on two opposite sides of the nozzle (25) and are symmetrically arranged; one sleeve (22) is connected to a pair of air pipes (23), the pair of air pipes (23) are respectively arranged on two opposite sides of the sleeve (22), and one sleeve (22) is communicated with one air passage (26); (1) Push the base (21) to the bottom of the furnace body (11), and then slowly lower the furnace body (11) so that the nozzle (25) is inserted into the air inlet (12); (2) pouring molten iron into the furnace body (11), and extending an oxygen blowing pipe into the furnace body (11); (3) nitrogen in the gas source is sprayed into the molten iron in the furnace body (11) through the gas pipe (23) and the gas channel (26), and the nozzles (25) are marked as A, B, C, and D in the clockwise direction, the gas channels (26) facing the clockwise direction are marked as A1, B1, C1, and D1, and the gas channels (26) facing the counterclockwise direction are marked as A2, B2, C2, and D2, respectively; (4) The air flow intensity is: when the bottom blowing device starts to operate, A2, B2, C1, and D2 are closed, D1>A1>B1>C2, and the oxygen blowing pipe is moved to the top of the nozzle (25) D; After 30-60 seconds, A2, B2, C2, and D1 are closed, A1>B1>C1>D2, and the oxygen blowing tube is moved to the top of the nozzle (25) A; After 30-60 seconds, A1, B2, C2, and D2 are closed, B1>C1>D1>A2, and the oxygen blowing tube is moved to the top of the nozzle (25) B; After 30-60 seconds, A2, B1, C2, and D2 are closed, C1>D1>A1>B2, and the oxygen blowing tube is moved to the top of the nozzle (25) C; (5) Repeat step (4) until the vanadium in the molten iron is fully converted into iron slag, and then discharge the iron slag and molten iron.

2. The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device according to claim 1, characterized in that: The air inlet holes (12) are distributed along the circumferential direction of the bottom of the furnace body (11); and the distances between the plurality of air inlet holes (12) and the axis of the furnace body (11) are all different.

3. The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device according to claim 1, characterized in that: The projection of the upper end of the air passage (26) on a horizontal plane is parallel to the tangent direction of the circumference of the furnace body (11) at the nozzle (25).

4. The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device according to claim 1, characterized in that: The lower end of the nozzle (25) is provided with a straight-line limiting head, and the inner bottom wall of the sleeve (22) is provided with a straight-line limiting groove; the limiting head is clamped in the limiting groove, and the pair of air pipes (23) are located at the same height.

5. The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device according to claim 1, characterized in that: The upper end of the sleeve (22) is provided with a trumpet-shaped opening; the lower end of the air inlet (12) is provided with a trumpet-shaped opening.

6. The quenching and tempering method of the vanadium-containing pig iron purification quenching and tempering device according to claim 1, characterized in that: A spring (24) is provided between the sleeve (22) and the base (21).

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