Small oxygen supply sleeve of oxygen blast furnace and mounting method of small oxygen supply sleeve

Abstract

The invention belongs to the technical field of blast furnace ironmaking, and particularly discloses an oxygen blast furnace gas supply small sleeve and an installation method thereof.The oxygen blast furnace gas supply small sleeve comprises a small sleeve outer wall and a small sleeve channel, the small sleeve channel is located in the middle of the small sleeve, a hollow cavity is formed in the small sleeve outer wall, a pressing contact surface is arranged on the small sleeve and is an inwards-concave arc surface, and an annular bottom wall is arranged on the periphery of the pressing contact surface; a water inlet and a water outlet are formed in the annular bottom wall, an oxygen channel is formed in the outer wall of the small sleeve, the inlet end of the oxygen channel is located in the three o'clock direction of the annular bottom wall, the outlet end of the oxygen channel is located in a small sleeve channel, and an annular oxygen channel is formed in the section 50 mm away from the rear end face of the small sleeve. And a plurality of circular hole channels with the same size for communicating the small sleeve channel are uniformly distributed on the annular oxygen channel. The combustion efficiency of pulverized coal can be improved, and abrasion of high-temperature gas to the small sleeve and a hearth side wall brick lining is reduced.

Description

Technical Field

[0001] This invention relates to the field of blast furnace ironmaking technology, and in particular to an oxygen blast furnace gas supply sleeve and its installation method. Background Technology

[0002] The tuyere sleeve is one of the most critical components and operates under the harshest conditions in blast furnace equipment. Its technical background revolves around the core objective of ensuring the long-term stable, efficient, and smooth operation of the blast furnace.

[0003] The tuyeres are the main channel for high-temperature blast furnace air to enter the furnace. The tuyer sleeve is the crucial link between the furnace interior and exterior, connecting the blast furnace body (hot zone) with the external cooling water and air supply systems. It is a critical point where energy, material, and information flows converge. Its front end operates in a near-2000°C environment, with molten slag exceeding 1400°C. The temperature of the medium passing through the tuyer sleeve is also above 1000°C, making its working environment extremely harsh. The tuyer sleeve requires a rationally designed front-end shape and injection angle, directly affecting the combustion efficiency of pulverized coal, the shape and size of the swirling zone, and consequently, the rational distribution of gas flow within the furnace and the activity level of the hearth. The tuyer sleeve itself is an integrated system encompassing metallurgy, heat transfer, fluid mechanics, and materials science. Its technological level directly reflects the advanced level of modern blast furnace smelting.

[0004] The main problems with the small tuyere sleeves currently used in blast furnaces are as follows: Low-carbon smelting is the future development trend of blast furnaces. In hydrogen-rich carbon-cycle oxygen blast furnaces, high-temperature coal gas, oxygen, and pulverized coal are injected. The various injection media interact with each other, and improper handling can affect the safety, stability, and long service life of the system. Currently, the traditional small-set structure is not suitable for low-carbon blast furnace processes and has a short service life.

[0005] The currently developed oxygen blast furnace tuyeres device, when the amount of pulverized coal injected reaches a certain level, is affected by the injected oxygen and injected coal gas, and the small sleeve parts in the injection direction are prone to wear. The currently developed oxygen blast furnace tuyeres have relatively low pulverized coal combustion efficiency. Summary of the Invention

[0006] To address the problems mentioned above, the present invention provides an oxygen blast furnace gas supply sleeve and its installation method.

[0007] To achieve the above objectives, the basic solution provided by this invention is as follows: an oxygen blast furnace gas supply sleeve, comprising an outer wall of the sleeve and a sleeve channel, wherein the sleeve channel is located in the middle of the sleeve, the inner part of the outer wall of the sleeve is a hollow cavity, the sleeve is provided with a pressing contact surface, the pressing contact surface is an inwardly concave arc surface, the pressing contact surface is surrounded by a circular bottom wall, the circular bottom wall is provided with a water inlet and a water outlet, the outer wall of the sleeve is provided with an oxygen channel, the inlet end of the oxygen channel is located at the three o'clock position of the circular bottom wall, the outlet end of the oxygen channel is located inside the sleeve channel, and an annular oxygen passage is provided at a cross-section 50mm from the rear end face of the sleeve, the annular oxygen passage having a plurality of circular channels of the same size evenly distributed on it for connecting the sleeve channel.

[0008] Furthermore, the front and middle portions of the oxygen channel are rectangular.

[0009] Furthermore, the cross-sectional area of ​​the rectangular oxygen channel is more than 1.1 times larger than the cross-sectional area of ​​the annular oxygen channel.

[0010] Furthermore, the cross-sectional area of ​​the annular oxygen channel is greater than 1.1 times the sum of the areas of the several circular channels.

[0011] Furthermore, both the annular oxygen channel and the circular channel are made of wear-resistant and high-temperature resistant ceramic material.

[0012] Furthermore, the angle between each of the circular channels and the inner wall of the small sleeve channel is 15°-75°, and the air outlet direction is towards the rear of the small sleeve.

[0013] A method for installing a gas supply sleeve in an oxygen blast furnace includes the following steps: S1. Place the small sleeve into the air vent. When installing the small sleeve, tilt it downwards by 3°-6° and to the right by 3°-6°. S2. Insert the direct-blowing pipe into the air outlet; S3. Press the top of the straight blow tube against the pressing contact surface of the small sleeve; S4. Open the sealing gas and check if there is any air leakage at the air outlet. If there is any air leakage, readjust the position of the direct blow pipe and the small sleeve. If there is no air leakage, connect the direct blow pipe to the equipment pipeline that delivers high-temperature gas.

[0014] Furthermore, step S2 also includes inserting the pulverized coal injection pipe diagonally above the direct injection pipe into the small sleeve channel, extending it to 50-100mm from the circular channel.

[0015] Furthermore, during blast furnace operation, the oxygen flow rate at the outlet end of the circular channel is controlled at 120-160 m / s, and the oxygen flow rate at the outlet end of the circular channel is 50-100 m / s lower than the medium flow rate in the small sleeve channel.

[0016] Compared with the prior art, the advantages of this invention are: (1) The design structure of this small set can meet the requirements of all-oxygen blast furnace smelting and is in line with the development trend of low-carbon smelting; (2) The structural design of the small set is that a uniform oxygen nozzle is arranged around the outlet at the rear end of the small set. The area of ​​the oxygen nozzle is smaller than the cross-sectional area of ​​the oxygen channel. Both the oxygen channel and the annular nozzle are designed with wear-resistant ceramic. The material has strong wear resistance and deformation resistance, so it can ensure that each nozzle of the annular oxygen nozzle can spray oxygen evenly.

[0017] (3) In this small tuyer, before the pulverized coal enters the furnace, the pulverized coal injection airflow meets the dual airflow of hot air blowing and oxygen ring jet, and the correction towards the center of the tuyer is stronger than that of the traditional blast furnace. This not only improves the combustion efficiency of pulverized coal, but also improves the position and shape of the tuyer swirling zone.

[0018] (4) By setting an oxygen ring injection channel in the small set, the present invention can more effectively improve the combustion efficiency of pulverized coal by increasing the oxygen concentration in the gas, improve the position and shape of the tuyere swirl zone, and reduce the wear of pulverized coal injection on the small set equipment. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of an oxygen blast furnace gas supply sleeve according to the present invention; Figure 2 for Figure 1 Sectional view of AA. Detailed Implementation

[0020] The present invention will be further described in detail below through specific embodiments: The reference numerals in the accompanying drawings include: 1. Outer wall of the small sleeve; 2. Small sleeve channel; 3. Pressing contact surface; 4. Circular bottom wall; 5. Oxygen channel; 6. Circular oxygen channel; 7. Circular hole; 8. Hollow cavity.

[0021] like Figure 1 and Figure 2As shown: A small oxygen blast furnace gas supply jacket includes an outer wall 1 and a small jacket channel 2. The small jacket channel 2 is located in the middle of the jacket. The outer wall 1 has a hollow cavity 8. The jacket has a pressing contact surface 3, which is a concave arc surface. The pressing contact surface 3 is surrounded by a circular bottom wall 4, which has an inlet and an outlet. An oxygen channel 5 is provided inside the outer wall 1. The inlet end of the oxygen channel 5 is located at the three o'clock position of the circular bottom wall 4, and the outlet end of the oxygen channel 5 is located inside the small jacket channel 2. An annular oxygen passage 6 is provided at a cross-section 50 mm from the rear end face of the jacket. Several circular channels 7 of the same size are evenly distributed on the annular oxygen passage 6 to connect to the small jacket channel 2. The front and middle parts of the oxygen channel 5 are rectangular. The cross-sectional area of ​​the rectangular channel of the oxygen channel 5 is more than 1.1 times the cross-sectional area of ​​the annular oxygen passage 6. The cross-sectional area of ​​the annular oxygen passage 6 is greater than 1.1 times the sum of the areas of the several circular channels 7. Both the annular oxygen channel 6 and the circular channel 7 are made of wear-resistant and high-temperature resistant ceramic material. The angle between each circular channel 7 and the inner wall of the small sleeve channel 2 is 15°-75°, and the gas outlet direction is towards the rear of the small sleeve.

[0022] A method for installing a gas supply sleeve in an oxygen blast furnace includes the following steps: S1. Place the small sleeve into the air vent. When installing the small sleeve, tilt it downwards by 3°-6° and to the right by 3°-6°. S2. Insert the direct-blowing pipe into the air outlet; S3. Press the top of the straight blow tube against the pressing contact surface 3 of the small sleeve; S4. Open the sealing gas and check if there is any air leakage at the air outlet. If there is any air leakage, readjust the position of the direct blow pipe and the small sleeve. If there is no air leakage, connect the direct blow pipe to the equipment pipeline that delivers high-temperature gas.

[0023] Step S2 also includes inserting the pulverized coal injection pipe obliquely above the direct-fired pipe into the small sleeve channel 2 and extending it to a distance of 750-100mm from the circular channel; during blast furnace operation, the oxygen flow rate at the outlet end of the circular channel 7 is controlled at 120-160m / s, and the oxygen flow rate at the outlet end of the circular channel 7 is 50-100m / s lower than the medium flow rate in the small sleeve channel 2.

[0024] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An oxygen blast furnace delivery tip characterized by, It comprises a sleeve outer wall (1) and a sleeve channel (2), the sleeve channel (2) is located in the middle of the sleeve, the sleeve outer wall (1) is a hollow cavity (8), the sleeve is provided with a pressing contact surface (3), the pressing contact surface (3) is a concave arc surface, the pressing contact surface (3) is surrounded by a circular bottom wall (4), the circular bottom wall (4) is provided with a water inlet and a water outlet, the sleeve outer wall (1) is provided with an oxygen channel (5), the inlet end of the oxygen channel (5) is located at the three o'clock direction of the circular bottom wall (4), the outlet end of the oxygen channel (5) is located inside the sleeve channel (2), a ring-shaped oxygen channel (6) is arranged at the section 50mm away from the rear end surface of the sleeve, and the ring-shaped oxygen channel (6) is uniformly provided with a plurality of circular holes (7) of the same size for communicating the sleeve channel (2).

2. An oxygen blast lance gas delivery shroud according to claim 1, characterised in that, The front part and the middle part of the oxygen channel (5) are rectangular.

3. An oxygen blast lance gas delivery shroud according to claim 1, characterized in that, The cross-sectional area of the rectangular channel of the oxygen channel (5) is greater than 1.1 times the cross-sectional area of the ring-shaped oxygen channel (6).

4. An oxygen blast lance gas delivery shroud according to claim 1 wherein, The cross-sectional area of the ring-shaped oxygen channel (6) is greater than 1.1 times the sum of the areas of the plurality of circular holes (7).

5. An oxygen blast lance gas delivery shroud according to claim 1 wherein, The materials of the ring-shaped oxygen channel (6) and the circular holes (7) are wear-resistant and high-temperature-resistant ceramic materials.

6. An oxygen blast lance gas delivery shroud according to claim 1 wherein, The included angle between each circular hole (7) and the inner wall of the sleeve channel (2) is 15°-75°, and the gas outlet direction is towards the rear of the sleeve.

7. A method for installing a small gas supply sleeve in an oxygen blast furnace, characterized in that, It comprises the following steps: S1, the sleeve (9) is placed in the tuyere, and the sleeve (9) is inclined downward by 3°-6° and inclined to the right by 3°-6° during installation; S2, the straight blowing pipe (10) is placed in the tuyere; S3, the top end of the straight blowing pipe (10) is tightly pressed against the pressing contact surface (3) of the sleeve (9); S4, open the sealing gas, check whether the tuyere leaks, if the leakage phenomenon occurs, adjust the position of the straight blowing pipe (10) and the sleeve (9); if the leakage phenomenon does not occur, connect the straight blowing pipe (10) with the device pipeline for sending high-temperature gas.

8. A method of installing an oxygen blast furnace gas delivery bushing according to claim 7, characterised in that, In step S2, the coal injection pipe (11) obliquely above the straight blowing pipe (10) is inserted into the sleeve channel (2) and extends to 50-100mm away from the circular hole (7).

9. A method of installing an oxygen blast furnace gas delivery bushing as defined in claim 8, wherein, During the operation of the blast furnace, the oxygen flow rate at the outlet end of the circular hole (7) is controlled at 120-160m / s, and the oxygen flow rate at the outlet end of the circular hole (7) is lower than the medium flow rate in the sleeve channel (2) by 50-100m / s.

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