Oxygen lance capable of improving heat source of converter and use method of oxygen lance

Abstract

The invention discloses an oxygen lance capable of improving the heat source of a converter and a using method thereof.The oxygen lance structurally comprises an oxygen lance tube body of a tubular structure, a total oxygen supply channel is formed in one end of the oxygen lance tube body, a set of oxygen lance main holes are formed in the bottom end of the oxygen lance tube body, and the oxygen lance further comprises a set of oxygen lance auxiliary hole bodies; a set of oxygen lance auxiliary hole body grooves are formed in the oxygen lance barrel body in the circumferential direction, the oxygen lance auxiliary hole bodies are detachably installed in the oxygen lance auxiliary hole body grooves in a replaceable mode, and the oxygen lance auxiliary hole bodies are internally provided with gas channel structures for preventing auxiliary hole oxygen flow from diffusing. By adopting the device and the method disclosed by the invention, the heat source of the converter can be increased, the scrap steel ratio of the converter can be increased, the oxygen flow of the auxiliary hole can be kept in a set direction after going out of the hole, the burning loss caused by oxygen diffusion at the outlet of the auxiliary hole is avoided, the secondary combustion reaction area of the oxygen lance is prolonged and enlarged, and the service life of the converter is prolonged. And the heating effect and the service life of the oxygen lance are improved.

Description

Technical Field

[0001] The invention relates to the technical field of converter steelmaking, and in particular to an oxygen lance for improving the heat source of a converter and a use method thereof. Background Art

[0002] For the blast furnace-converter process, increasing the scrap ratio in the converter process and reducing the consumption of molten iron are the key factors to reduce CO 2 To maintain the thermal balance of the converter, the converter usually adopts two methods to compensate for the heat: preheating scrap steel and adding heat supplement (mainly C and Si materials). Preheating scrap steel requires natural gas or coal gas combustion to heat up, and a heating device is required. The carbon emissions generated during the preheating process are not reduced overall. Although the addition of carbonaceous heat supplement has a significant temperature compensation effect, it cannot effectively reduce CO 2 Emissions: The addition of siliceous heating agent during the blowing process generates silicon oxide, which reduces the basicity of the slag. The amount of lime must be increased to ensure the smelting effect of the converter. The amount of converter slag increases, which is not conducive to the development requirements of green environmental protection.

[0003] The converter secondary combustion oxygen lance technology is a clean temperature raising technology. The principle of the secondary combustion oxygen lance is to use the oxygen jet ejected from the auxiliary hole to burn with the CO gas in the furnace to generate a large amount of heat, so that the converter's own heat can be fully utilized, thereby increasing the converter scrap ratio. According to whether the main and auxiliary oxygen holes share an oxygen channel, it can be divided into a single-flow secondary combustion oxygen lance and a double-flow secondary combustion oxygen lance. The characteristics of the double-flow secondary combustion oxygen lance are that the main and auxiliary oxygen holes are controlled by independent oxygen channels, and the oxygen flow and oxygen pressure of the main oxygen flow and the auxiliary oxygen flow can be controlled separately in different smelting periods. The double-flow secondary combustion oxygen lance has the advantage of a higher secondary combustion rate, but its structure is relatively complex, and the oxygen supply system of the original oxygen lance needs to be modified, which has a high investment cost. The characteristics of the single-flow secondary combustion oxygen lance are that the main and auxiliary oxygen holes share an oxygen channel, and the flow and pressure of the main and auxiliary holes oxygen cannot be controlled separately, but there is no need to carry out large-scale modification of the original gun body, which is suitable for large-scale production promotion and application.

[0004] In the related single-channel converter secondary combustion oxygen lance technology, the inner wall of the secondary hole is usually designed as a straight cylinder or an inverted cone, and the speed of the secondary oxygen stream is much lower than the oxygen flow speed of the Laval nozzle of the main hole of the oxygen lance. The secondary combustion oxygen lance with this structure has a thinner connection between the secondary hole and the outer tube of the oxygen lance, and the secondary oxygen stream has a low speed. It is easy to disperse under the influence of the wall effect, especially when the converter oxygen supply pressure and oxygen supply flow fluctuate, the dispersion phenomenon is aggravated, the secondary combustion zone generated by the secondary hole is far from the molten steel liquid surface, the heat released by the combustion of CO is taken away by the rising furnace gas, and the molten steel heat supplement effect is poor; at the same time, the dispersed secondary oxygen stream will also cause the outlet of the secondary hole to be prone to wear, slag adhesion and ablation. Once the outlet of the secondary hole is ablated and water seeps, the entire oxygen lance needs to be scrapped and replaced, resulting in a low overall service life of the oxygen lance.

[0005] In the prior art, there are a kind of self-rotating secondary combustion oxygen lance disclosed in patent CN105154617A, a method for improving the heat source of the dephosphorization converter smelting process disclosed in patent CN108300831A, a single-flow channel secondary combustion oxygen lance for improving the scrap steel ratio of the converter disclosed in patent CN108977620A and a method of using the same, and a single-flow channel secondary combustion oxygen lance disclosed in patent CN 108977620A and a method of using the same; the prior art solutions mainly have the following problems: 1. Only the heating effect of the oxygen lance is paid attention to, and the service life of the oxygen lance is rarely paid attention to; 2. The inner wall surface of the auxiliary hole of the oxygen lance is usually designed to be a straight cylinder or an inverted cone, which does not really solve the problem that the jet velocity of the auxiliary hole of the non-Laval hole type is low and the scattered flow burning lance is easy to occur; 3. The main hole body and the auxiliary hole body of the oxygen lance are designed as an integral whole, and the auxiliary hole cannot be replaced after being burned, and the overall replacement cost is high. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention provides an oxygen lance for improving the heat source of a converter and a method for using the same. The heat supplement is stable and the outlet of the auxiliary hole of the oxygen lance is not easily burned.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] An oxygen lance for improving the heat source of a converter comprises an oxygen lance tube body, the oxygen lance tube body is in a tubular structure, one end of the oxygen lance tube body is a total oxygen supply channel, a group of oxygen lance main holes are arranged at the bottom end of the oxygen lance tube body, and a group of oxygen lance auxiliary hole bodies are also included. A group of oxygen lance auxiliary hole body grooves are arranged on the circumference of the oxygen lance tube body, the oxygen lance auxiliary hole bodies are detachably and replaceably installed in the oxygen lance auxiliary hole body grooves, and the oxygen lance auxiliary hole body has a gas channel structure to prevent the auxiliary hole oxygen flow stream from being scattered.

[0009] The group of oxygen lance main holes and the group of oxygen lance auxiliary holes are evenly spaced and staggered.

[0010] The oxygen lance tube body comprises an oxygen lance outer tube, an oxygen lance middle tube and an oxygen lance inner tube which are arranged in sequence from outside to inside; a water return channel is between the oxygen lance outer tube and the oxygen lance middle tube, and a water inlet channel is between the oxygen lance middle tube and the oxygen lance inner tube.

[0011] The main hole of the oxygen lance is a Laval type structure, the angle β between its central axis and the central axis of the oxygen lance tube body is 9-13°, the expansion angle θ is 6-7°, the throat diameter is 37-40mm, the outlet diameter is 48-50mm, and the Mach number is 1.95-2.05Ma.

[0012] The auxiliary hole body slot of the oxygen lance is a slot hole structure with an inverted taper, and the inverted taper is 1-2 degrees.

[0013] The angle α between the central axis of the oxygen lance auxiliary hole body and the central axis of the oxygen lance tube body is 25-35°.

[0014] The gas channel structure in the auxiliary hole body of the oxygen lance is a spiral gas channel.

[0015] The outer end of the auxiliary hole body of the oxygen lance protrudes from the outer edge of the oxygen lance tube body by 3 to 5 mm, and the front end of the auxiliary hole body of the oxygen lance protrudes from the oxygen lance tube body by 3 to 5 mm.

[0016] The ultra-high temperature ceramic coating is prepared around the oxygen outlet end face of the oxygen lance auxiliary hole body by supersonic plasma spraying.

[0017] A method for using the oxygen lance for increasing the heat source of the converter is:

[0018] According to the constant pressure variable gun position operation process, the converter blowing and slag splashing protection are carried out, and the oxygen pressure supplied by the inner tube of the oxygen gun is controlled at 0.8-1.1Mpa, and the oxygen supply flow rate is controlled at 17000-25000m 3 / h; To protect the oxygen lance and furnace bottom, the lowest lance position is not less than 0.9m, and the blowing lance position is 1.0-1.3m; the nitrogen pressure during slag splashing is controlled at 1.0-1.2Mpa, the slag splashing lance position is 0.9-1.2mm, the slag splashing time is 2-5min, and the oxygen blowing intensity is 2.5-4.5Nm 3 / t·min, bottom blowing intensity is 0.01~0.03Nm 3 / t·min.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The main hole of the oxygen lance provided by the present invention adopts a Laval type structure, and the inner wall of the auxiliary hole body is processed with a plurality of concave and convex spiral gas channels, the main hole and the auxiliary hole are evenly spaced and staggered, and the oxygen flow of the auxiliary hole body spins during the injection process, so that the oxygen flow of the auxiliary hole can still maintain a predetermined direction after exiting the hole without scattered flow, and the outlet of the auxiliary hole of the oxygen lance is not easy to burn;

[0021] 2. The oxygen lance main hole body and the oxygen lance auxiliary hole body of the present invention are designed separately. During the manufacturing process of the oxygen lance, the parameters of the spiral gas channel of the oxygen lance auxiliary hole body can be flexibly adjusted according to the furnace characteristics of different converters, without the need to modify the main hole body of the oxygen lance; when the main hole body and the auxiliary hole body of the oxygen lance are assembled, the advantages of the inverted taper structure are utilized, and a welding and mortise method is adopted. Once the welding area at the front end of the oxygen lance auxiliary hole body is ablated, the original oxygen lance auxiliary hole body can be easily removed, which is convenient for replacing a new oxygen lance auxiliary hole body, avoiding the problem of scrapping and replacing the entire oxygen lance due to ablation of the oxygen lance auxiliary hole body, and further improving the life of the oxygen lance;

[0022] 3. Compared with the traditional secondary combustion oxygen lance, the secondary combustion reaction area of ​​the oxygen lance is longer, the molten steel temperature raising effect is more significant, and at the same time, the burning caused by oxygen dispersion at the outlet of the secondary hole is avoided, and the service life of the oxygen lance is increased; under the same smelting conditions, the life and use method of the oxygen lance are 50-100 times longer than the traditional single-channel secondary combustion oxygen lance in smelting furnaces, the heating effect is increased by more than 10°C, the scrap steel loading capacity of the converter is increased by 6kg / t steel, the converter smelting cycle is shortened by 1.5-2.0min, the carbon emission per ton of steel is reduced by 10kg / t steel, and the heat supplement is stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The following is a brief description of the contents and symbols in the drawings of this specification:

[0024] Figure 1 It is a schematic diagram of the front cross section of the oxygen lance nozzle of the present invention.

[0025] Figure 2 It is a top view cross-sectional schematic diagram of the oxygen lance nozzle of the present invention.

[0026] Figure 3 It is a schematic diagram of the main cross-section of the main hole body of the oxygen lance nozzle of the present invention.

[0027] Figure 4 It is a top view cross-sectional schematic diagram of the main hole body of the oxygen lance nozzle of the present invention.

[0028] Figure 5 It is a schematic diagram of the main cross-section of the auxiliary hole body of the oxygen lance nozzle of the present invention.

[0029] Figure 6 For along Figure 5 AA cross-sectional view.

[0030] Figure 7 It is a three-dimensional stereogram of the auxiliary hole body of the oxygen lance nozzle of the present invention.

[0031] In the figure:

[0032] 1-0, oxygen lance main hole body, 1-1, oxygen lance outer tube, 1-2, oxygen lance middle tube, 1-3, oxygen lance inner tube, 1-4, water distribution plate, 1-5, oxygen lance main hole, 1-6, oxygen lance auxiliary hole body groove, 2-0, oxygen lance auxiliary hole body, 2-1, concave spiral gas channel, 2-2, convex spiral gas channel, 2-3, oxygen lance auxiliary hole body front end welding area, 2-4, oxygen lance auxiliary hole body rear end high temperature resistant O-type gasket tenon joint area. DETAILED DESCRIPTION

[0033] The specific implementation modes of the present invention will be further explained in detail below through the description of embodiments with reference to the accompanying drawings.

[0034] like Figures 1 to 7As shown, the oxygen lance for improving the heat source of the converter includes an oxygen lance tube body, which is a tubular structure; specifically, the oxygen lance tube body includes an oxygen lance main hole body and an oxygen lance auxiliary hole body; one end of the oxygen lance main hole body is a total oxygen supply channel, a group of oxygen lance main holes are provided at the bottom end of the oxygen lance main hole body, a group of oxygen lance auxiliary hole body grooves are provided on the circumference of the oxygen lance main hole body, the oxygen lance auxiliary hole body is detachably and replaceably installed in the oxygen lance auxiliary hole body groove, and the oxygen lance auxiliary hole body has a gas channel structure to avoid the auxiliary hole oxygen flow stream from being scattered.

[0035] Based on the problem of long life and high-efficiency heat supplement of converter oxygen lance under the background of "dual carbon", a special oxygen lance is designed to improve the heat source of converter. The main hole of the oxygen lance adopts Laval structure, and the inner wall of the auxiliary hole body is processed with multiple concave and convex spiral gas channels. The main hole and the auxiliary hole are evenly spaced and staggered. The oxygen flow of the auxiliary hole body can spin during the injection process, which avoids the dispersion of the oxygen flow stream of the auxiliary hole, so that the auxiliary oxygen flow stream can still maintain the established direction after leaving the hole.

[0036] Compared with the traditional secondary combustion oxygen lance, the secondary combustion reaction area of ​​the oxygen lance is longer, which makes the molten steel temperature increase more significant. At the same time, it avoids the burning caused by oxygen dispersion at the outlet of the secondary hole and increases the service life of the oxygen lance.

[0037] The main hole body and auxiliary hole body of the traditional secondary combustion oxygen gun adopt an integral design, and the auxiliary hole cannot be replaced after being burned. The main hole body and auxiliary hole body of the oxygen gun of the present invention are designed separately, and the auxiliary hole body can be disassembled and replaced after being burned, thereby further improving the overall service life of the oxygen gun.

[0038] A method for using an oxygen lance to increase the heat source of a converter is given, which requires a low lance position, high oxygen supply intensity, and high oxygen pressure. The converter temperature rises by 25 to 30°C, and the smelting cycle is shortened by 1.5 to 2.0 minutes; the heat supplement is stable.

[0039] The preferred structural scheme of the present invention is:

[0040] The present invention provides an oxygen lance structure for improving the heat source of a converter, the oxygen lance structure comprising an oxygen lance main hole body and an oxygen lance auxiliary hole body, the oxygen lance main hole body is tubular and comprises an oxygen lance outer tube, an oxygen lance middle tube, an oxygen lance inner tube, a water distribution plate, an oxygen lance main hole, and an oxygen lance auxiliary hole body groove in sequence from outside to inside; the oxygen lance main hole body is provided with 4 to 5 oxygen lance auxiliary hole body grooves with an inverted taper of 1 to 2 degrees in the circumferential direction, and 4 to 5 oxygen lance main holes are provided at the bottom, the oxygen lance outer tube and the oxygen lance middle tube are provided with a return water channel, the oxygen lance middle tube and the oxygen lance inner tube are provided with a water inlet channel, the oxygen lance inner tube is provided with a total oxygen supply channel, and a water distribution plate is provided around the oxygen lance main hole. The oxygen lance main hole is a Laval type structure, the angle β between the central axis and the central axis of the oxygen lance main hole body is 9 to 13 degrees, the expansion angle θ is 6 to 7 degrees, the throat diameter is 37 to 40 mm, the outlet diameter is 48 to 50 mm, and the Mach number is 1.95 to 2.05 Ma.

[0041] The main hole oxygen lance and the auxiliary hole of the oxygen lance are designed and processed separately; the auxiliary hole of the oxygen lance is installed in the auxiliary hole groove of the oxygen lance, and the angle α between the central axis and the central axis of the main hole of the oxygen lance is 25-35°; the inner wall of the auxiliary hole of the oxygen lance is processed with 3-6 concave and convex spiral gas channels; the pitch L of the concave spiral gas channel and the convex spiral gas channel are the same (about 130-150mm); the curvature radius R of the concave spiral gas channel 1 The curvature radius of the convex spiral gas channel is R 2 is 0.8~1.5mm, and R 1 =nR 2 The oxygen lance main hole and the oxygen lance auxiliary hole body are evenly spaced and staggered along the oxygen lance main hole body; the oxygen lance auxiliary hole body is installed in the oxygen lance auxiliary hole body groove, and the main and auxiliary oxygen holes share an oxygen channel.

[0042] The outer wall surface of the oxygen lance auxiliary hole body is in an inverted cone shape with γ of 1 to 2 degrees, the oxygen lance auxiliary hole body groove protrudes 3 to 5 mm from the oxygen lance outer tube, and the corresponding front end of the oxygen lance auxiliary hole body protrudes 3 to 5 mm from the oxygen lance outer tube, and the protruding length is equal to the width of the welding area between the oxygen lance outer tube and the oxygen lance auxiliary hole body; the rear end of the oxygen lance auxiliary hole body is communicated with the oxygen lance inner tube, and the outer wall surface of the rear end of the oxygen lance auxiliary hole body is provided with a 3 to 5 mm high temperature resistant O-type gasket tenon joint area. During the oxygen supply period of the oxygen lance, the high temperature resistant O-type gasket tenon joint area at the rear end of the oxygen lance auxiliary hole body will further self-tighten under the influence of the inverted taper, oxygen pressure, and thermal expansion.

[0043] In order to further reduce the possibility of ablation in the welding area between the oxygen lance outer tube and the oxygen lance auxiliary hole body, an ultra-high temperature ceramic coating is prepared around the oxygen flow outlet end face of the oxygen lance auxiliary hole body by supersonic plasma spraying.

[0044] The oxygen blowing flow rate of the main hole of the oxygen lance accounts for 85% to 90% of the total oxygen supply flow rate of the inner tube of the oxygen lance; the oxygen blowing flow rate Q of the auxiliary hole body accounts for 10% to 15% of the total oxygen supply flow rate of the inner tube of the oxygen lance; from the cross section perpendicular to the central axis of the auxiliary hole body, the oxygen distribution inside the auxiliary hole body of the oxygen lance is "fan-shaped". In the process of oxygen flowing forward, the high-pressure "fan-shaped" oxygen flow stream will rotate with the spiral gas channel, and the spin angular velocity ω=KQ / (L·(R 1 -R 2 ) 2 ).

[0045] The embodiment of the present invention also provides a method for using an oxygen lance to improve the heat source of a converter. The method includes performing converter blowing and slag splashing protection according to a constant pressure variable lance position operation process. To avoid the phenomenon of "soft blowing" of the auxiliary hole oxygen flow, the oxygen pressure supplied by the inner tube of the oxygen lance is controlled at 0.8-1.1Mpa, and the oxygen supply flow rate is controlled at 17000-25000m3 / h; To protect the oxygen lance and furnace bottom, the lowest lance position is not less than 0.9m, and the blowing lance position is 1.0-1.3m; the nitrogen pressure during slag splashing is controlled at 1.0-1.2Mpa, the slag splashing lance position is 0.9-1.2mm, the slag splashing time is 2-5min, and the oxygen blowing intensity is 2.5-4.5Nm 3 / t·min, bottom blowing intensity is 0.01~0.03Nm 3 / t·min.

[0046] The present invention has the following effects: 1. The main hole of the oxygen gun provided by the present invention adopts a Laval type structure, and the inner wall of the auxiliary hole body is processed with a plurality of concave and convex spiral gas channels, the main hole and the auxiliary hole are evenly spaced and staggered, and the oxygen flow of the auxiliary hole body spins during the injection process, so that the oxygen flow of the auxiliary hole can still maintain a predetermined direction after exiting the hole without dispersion. 2. The main hole body and the auxiliary hole body of the oxygen gun of the present invention are designed separately. During the production process of the oxygen gun, the parameters of the spiral gas channel of the auxiliary hole body of the oxygen gun can be flexibly adjusted according to the furnace characteristics of different converters, without the need to modify the main hole body of the oxygen gun; when the main hole body and the auxiliary hole body of the oxygen gun are assembled, the advantages of the inverted taper structure are utilized, and the welding and mortise method is adopted. Once the welding area at the front end of the auxiliary hole body of the oxygen gun is ablated, the original auxiliary hole body of the oxygen gun can be easily removed, which is convenient for replacing the new auxiliary hole body of the oxygen gun, avoiding the problem of scrapping and replacing the entire oxygen gun due to ablation of the auxiliary hole body of the oxygen gun, and further improving the life of the oxygen gun. 3. Compared with the traditional secondary combustion oxygen lance, the secondary combustion reaction area of ​​the oxygen lance is longer, the molten steel temperature raising effect is more significant, and at the same time, the burning caused by oxygen dispersion at the outlet of the secondary hole is avoided, thereby prolonging the service life of the oxygen lance; under the same smelting conditions, the life and use method of the oxygen lance are 50 to 100 times longer than that of the traditional single-channel secondary combustion oxygen lance, the heating effect is increased by more than 10°C, the scrap steel loading amount of the converter is increased by 6kg / t steel, the converter smelting cycle is shortened by 1.5 to 2.0min, and the carbon emission per ton of steel is reduced by 10kg / t steel.

[0047] The specific preferred embodiments of the present invention are:

[0048] The embodiment of the present invention provides an oxygen lance structure (such as Figure 1 and 2 ), the oxygen lance structure includes an oxygen lance main hole body 1-0 and an oxygen lance auxiliary hole body 2-0, the oxygen lance main hole body 1-0 (such as Figure 3 and Figure 4) is tubular and includes, from outside to inside, an oxygen lance outer tube 1-1, an oxygen lance middle tube 1-2, an oxygen lance inner tube 1-3, a water distribution plate 1-4, an oxygen lance main hole 1-5, and an oxygen lance auxiliary hole body groove 1-6; the oxygen lance main hole body 1-0 is provided with 4 oxygen lance auxiliary hole body grooves 1-6 with an inverted taper of 2° on the circumference, and 4 oxygen lance main holes 1-5 are provided on the bottom, and a water return channel is provided between the oxygen lance outer tube 1-1 and the oxygen lance middle tube 1-2. The water inlet channel is between the gun middle tube and the oxygen gun inner tube 1-3, the oxygen gun inner tube 1-3 is the total oxygen supply channel, and a water distribution plate 1-4 is arranged around the oxygen gun main hole 1-5; the oxygen gun main hole 1-5 is a Laval type structure, and the angle β between its central axis and the central axis of the oxygen gun main hole body is 11.5°, the expansion angle θ is 6.8°, the throat diameter is 38.6mm, the outlet diameter is 49.7mm, and the Mach number is 1.98Ma.

[0049] During the implementation of the present invention, the traditional secondary combustion oxygen lance is technically improved, and the oxygen lance main hole body 1-0 and the oxygen lance auxiliary hole body 2-0 are separately designed and processed; the oxygen lance auxiliary hole body 2-0 is installed in the oxygen lance auxiliary hole body groove 1-6, and the angle α between its central axis and the central axis of the oxygen lance main hole body 1-0 is 33°, and the inner wall surface of the oxygen lance auxiliary hole body 2-0 is processed with 6 concave and convex spiral gas channels; the pitch L of the concave spiral gas channel 2-1 and the convex spiral gas channel 2-2 are the same (both are 136mm); the curvature radius R of the concave spiral gas channel 2-1 is 100mm, and ... 1 The curvature radius of the convex spiral gas channel 2-2 is R 2 is 1.3 mm, and R 1 =5R 2 The oxygen lance main hole 1-5 and the oxygen lance auxiliary hole body 2-0 are evenly spaced and staggered along the oxygen lance main hole body 1-0; the oxygen lance auxiliary hole body 2-0 is installed in the oxygen lance auxiliary hole body groove 1-6, and the main and auxiliary oxygen holes share an oxygen channel.

[0050] The outer wall surface of the oxygen lance auxiliary hole body 2-0 is an inverted cone with γ of 2°, the oxygen lance auxiliary hole body groove 1-6 protrudes from the oxygen lance outer tube 1-1 by about 5mm, and the corresponding front end of the oxygen lance auxiliary hole body 2-0 protrudes from the oxygen lance outer tube 1-1 by about 5mm, and the protruding length is equal to the width of the oxygen lance outer tube 1-1 and the welding area 2-3 of the oxygen lance auxiliary hole body; the rear end of the oxygen lance auxiliary hole body 2-0 is connected to the oxygen lance inner tube 1-3, and the outer wall surface of the rear end of the oxygen lance auxiliary hole body 2-0 is provided with a 5mm high-temperature resistant O-type gasket tenon joint area 2-4. During the oxygen supply period of the oxygen lance, the high-temperature resistant O-type gasket tenon joint area 2-4 at the rear end of the oxygen lance auxiliary hole body will further self-tighten under the influence of the inverted taper, oxygen pressure, and thermal expansion.

[0051] In order to further reduce the possibility of ablation of the welding area between the oxygen lance outer tube 1-1 and the oxygen lance auxiliary hole body 2-0, an ultra-high temperature ceramic coating is prepared around the oxygen flow outlet end face of the oxygen lance auxiliary hole body 2-0 by supersonic plasma spraying.

[0052] The oxygen blowing flow rate of the oxygen lance main hole 1-5 accounts for 85% to 90% of the total oxygen supply flow rate of the oxygen lance inner tube 1-3; the oxygen blowing flow rate Q of the auxiliary hole body accounts for 10% to 15% of the total oxygen supply flow rate of the oxygen lance inner tube; from the cross section perpendicular to the central axis of the auxiliary hole body 2-0, the oxygen distribution inside the oxygen lance auxiliary hole body 2-0 is "fan-shaped" (such as Figure 3 ), in the process of oxygen flowing forward, the high-pressure "fan-shaped" oxygen flow will rotate along the spiral gas channels 2-1 and 2-2, and the spinning angular velocity ω = 19.2rad / s.

[0053] The device and method of the present invention can increase the heat source of the converter and improve the scrap steel ratio of the converter. At the same time, the oxygen flow of the auxiliary hole can maintain a predetermined direction after exiting the hole, thereby avoiding burning caused by oxygen dispersion at the outlet of the auxiliary hole, extending and expanding the secondary combustion reaction area of ​​the oxygen gun, and improving the heating effect and service life of the oxygen gun. The solution requires less equipment investment, low labor intensity, and is easy and simple to operate. It provides a new green, environmentally friendly and efficient thermal compensation technology for the converter.

[0054] The above is only an explanation of the preferred embodiments of the present invention, and the above technical features can be arbitrarily combined to form multiple embodiments of the present invention.

[0055] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. An oxygen lance for improving the heat source of a converter, comprising an oxygen lance tube body, wherein the oxygen lance tube body is a tubular structure, one end of the oxygen lance tube body is a total oxygen supply channel, and a group of oxygen lance main holes are provided at the bottom end of the oxygen lance tube body, characterized in that: The oxygen lance also includes a group of oxygen lance auxiliary hole bodies, wherein a group of oxygen lance auxiliary hole body grooves are provided on the circumference of the oxygen lance tube body, the oxygen lance auxiliary hole bodies are detachably and replaceably installed in the oxygen lance auxiliary hole body grooves, and the oxygen lance auxiliary hole bodies have a gas channel structure for preventing the auxiliary hole oxygen flow stream from being scattered.

2. The oxygen lance for increasing the heat source of the converter as claimed in claim 1, characterized in that: The group of oxygen lance main holes and the group of oxygen lance auxiliary holes are evenly spaced and staggered.

3. The oxygen lance for increasing the heat source of the converter as claimed in claim 1, characterized in that: The oxygen lance tube body comprises an oxygen lance outer tube, an oxygen lance middle tube and an oxygen lance inner tube which are arranged in sequence from outside to inside; a water return channel is between the oxygen lance outer tube and the oxygen lance middle tube, and a water inlet channel is between the oxygen lance middle tube and the oxygen lance inner tube.

4. The oxygen lance for increasing the heat source of the converter as claimed in claim 1, characterized in that: The main hole of the oxygen lance is a Laval type structure, the angle β between its central axis and the central axis of the oxygen lance tube body is 9-13°, the expansion angle θ is 6-7°, the throat diameter is 37-40mm, the outlet diameter is 48-50mm, and the Mach number is 1.95-2.05Ma.

5. The oxygen lance for increasing the heat source of the converter as claimed in claim 1, characterized in that: The auxiliary hole body slot of the oxygen lance is a slot hole structure with an inverted taper, and the inverted taper is 1-2 degrees.

6. The oxygen lance for increasing the heat source of the converter as claimed in claim 1, characterized in that: The angle α between the central axis of the oxygen lance auxiliary hole body and the central axis of the oxygen lance tube body is 25-35°.

7. The oxygen lance for increasing the heat source of a converter as claimed in claim 1, characterized in that: The gas channel structure in the auxiliary hole body of the oxygen lance is a spiral gas channel.

8. The oxygen lance for increasing the heat source of a converter as claimed in claim 1, characterized in that: The outer end of the auxiliary hole body of the oxygen lance protrudes from the outer edge of the oxygen lance tube body by 3 to 5 mm, and the front end of the auxiliary hole body of the oxygen lance protrudes from the oxygen lance tube body by 3 to 5 mm.

9. The oxygen lance for increasing the heat source of the converter as claimed in claim 8, characterized in that: The ultra-high temperature ceramic coating is prepared around the oxygen outlet end face of the oxygen lance auxiliary hole body by supersonic plasma spraying.

10. A method for using an oxygen lance for increasing the heat source of a converter as claimed in any one of claims 1 to 9, characterized in that: The method of use is: According to the constant pressure variable gun position operation process, the converter blowing and slag splashing protection are carried out, and the oxygen pressure supplied by the inner tube of the oxygen gun is controlled at 0.8-1.1Mpa, and the oxygen supply flow rate is controlled at 17000-25000m 3 / h; To protect the oxygen lance and furnace bottom, the lowest lance position is not less than 0.9m, and the blowing lance position is 1.0-1.3m; the nitrogen pressure during slag splashing is controlled at 1.0-1.2Mpa, the slag splashing lance position is 0.9-1.2mm, the slag splashing time is 2-5min, and the oxygen blowing intensity is 2.5-4.5Nm 3 / t·min, bottom blowing intensity is 0.01~0.03Nm 3 / t·min.

Images