Method for manufacturing a brick for a blast furnace tuyere

Abstract

The application relates to a method for manufacturing a blast furnace tuyere blocking brick, and belongs to the technical field of blast furnace iron-making. The method comprises the following manufacturing steps: applying a release agent in advance in a brick manufacturing mold to facilitate demolding; mixing and stirring castable material and water in a certain proportion, and pouring the mixture into the brick manufacturing mold; inserting a solid rod into the center of the castable material before the castable material dries, so as to manufacture a castable material hole; and demolding after the castable material completely dries, and the tuyere blocking brick is manufactured. The blast furnace tuyere blocking brick manufactured by the method has certain high-temperature resistance and suitable strength, and other excellent properties, so that the blast furnace tuyere blocking brick can be in a relatively stable hardness for a long time, thereby reducing the working strength of workers.

Description

Technical Field

[0001] This invention relates to the field of blast furnace ironmaking technology, specifically to a method for manufacturing bricks for blast furnace tuyeres. Background Technology

[0002] The tuyere is a crucial component in blast furnace ironmaking, used for air supply and pulverized coal injection. It typically consists of a large tuyere sleeve, a medium tuyere sleeve, and a small tuyere sleeve. When handling special furnace conditions, long-term shutdowns, major overhauls, or restarting a blast furnace, designated sections of the tuyere need to be sealed. Normally, each tuyere sealing operation involves first removing the air supply pipe, then plugging the small sleeve with bricks and refractory mortar, sealing it securely, reinstalling the air supply pipe, and finally completing the operation after pressure and leak testing. Because the process of removing and installing the air supply pipe is time-consuming, and ensuring the quality of the tuyere sealing is crucial—otherwise, failure to pass the pressure and leak tests will require reinstallation, or the tuyere may not be properly sealed, leading to subsequent air supply mortar blowing open and causing the tuyere to burn through—completing the tuyere sealing operation without removing the air supply pipe can save significant shutdown time.

[0003] In addition, choosing the right bricks is also crucial. If the bricks are too strong, it will make it difficult to plug the tuyeres, and may even force a shutdown and blockage of the tuyeres. However, the strength of bricks on the market varies, and purchased red bricks may not always be in a stable hardness state, which brings many uncertainties to the quality of blast furnace tuyer blockage. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings and defects of the existing technology by providing a method for manufacturing bricks for blast furnace tuyeres. The blast furnace tuyere bricks manufactured by this method utilize the excellent properties of iron storage trench casting material, such as certain high temperature resistance and suitable strength, so that they can maintain a relatively stable hardness even after long-term use, thereby reducing the workload of workers.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for manufacturing bricks for blast furnace tuyeres, characterized by the following manufacturing steps: S1, during manufacturing, a release agent is applied to the brick mold in advance to facilitate demolding; S2, the castable refractory and water are mixed in a certain proportion and stirred evenly, and then poured into the brick mold. The specific formula of the castable refractory is: Al2O3, corundum, white corundum, silicon carbide, magnesium, and bauxite, and the ratio of castable refractory to water is 20:1; S3, during casting... Before the tuyeres are dry, a solid rod is inserted into their center to create a hole for the tuyeres; S4, after the refractory material is completely dry, the tuyeres are demolded, and the tuyeres blockage bricks are completed; when using the tuyeres blockage bricks to block the tuyeres, the tuyeres blockage bricks are wrapped with refractory mortar on all sides; the strength and refractoriness of the tuyeres blockage bricks meet the following conditions: during the blast furnace smelting process, the tuyeres blockage bricks can not be blown open; during the process of blast furnace operators using steel rods to poke the tuyeres, the tuyeres can be pried open.

[0006] Furthermore, the brick-making mold is made of wood, hard plastic and steel plate materials.

[0007] Furthermore, the brick-making mold is made into a truncated "cone" smaller than the inner diameter of the small sleeve, based on the "cone" shape of the small sleeve head. The diameter of the end face with the larger diameter is smaller than the inner diameter of the small sleeve, so as to prevent the brick from being stuck at the front end of the small sleeve to block the air vent.

[0008] Furthermore, the diameter of the solid rod is 15mm-20mm, and the insertion depth is 20mm-25mm.

[0009] After adopting the above technical solution, the beneficial effects of the present invention are as follows: the blast furnace tuyeres bricks manufactured by this method utilize the high-temperature resistance and suitable strength of the iron storage trench casting material, which enable them to maintain a relatively stable hardness even after long-term use, thereby reducing the workload of workers. Attached Figure Description

[0010] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a drawing of the prefabricated mold for the special brick for blocking air vents of the present invention;

[0012] Figure 2 This is a cross-sectional view of a special brick used for blocking air vents;

[0013] Figure 3 This is a diagram showing the use of bricks specifically designed for blocking air vents. Detailed Implementation

[0014] See Figures 1-3 As shown, the technical solution adopted in this specific embodiment includes the following manufacturing steps:

[0015] S1. During the manufacturing process, a release agent is applied to the brick mold in advance to facilitate demolding. The brick mold can be made of wood, hard plastic, or steel plate. The brick mold is made with a truncated cone shape smaller than the inner diameter of the small sleeve, based on the cone shape of the small sleeve head. The diameter of the end face with the larger diameter is smaller than the inner diameter of the small sleeve to prevent the brick from blocking the air vent and getting stuck at the front end of the small sleeve.

[0016] S2, the castable and water are mixed in a certain proportion and stirred evenly, and then poured into the brick mold. The specific formula of the castable is: Al2O3, corundum, white corundum, silicon carbide, magnesium, bauxite, and the ratio of castable to water is 20:1.

[0017] S3. Before the cast brick dries, insert a solid rod with a diameter of 15mm-20mm into its center, with an insertion depth of 20mm-25mm, thus creating a hole in the cast brick. This hole allows the prepared blocking brick to be easily inserted into the small sleeve of the air vent when sealing it later.

[0018] S4. After the castable is completely dry, demold and make the air vent with bricks.

[0019] More specifically, the operator can prefabricate special bricks of different thicknesses and sizes for the blast furnace shut-off time and the ease of restoring the furnace condition.

[0020] A method for using bricks for blocking blast furnace tuyeres, characterized in that: it includes cast bricks made from any type of blast furnace tuyere bricks, wherein when using cast bricks to block tuyeres, the cast bricks are surrounded by refractory mortar, and the cast bricks can act as a skeleton.

[0021] The following is a specific embodiment of a method for manufacturing bricks for plugging tuyeres in blast furnaces: Example 1

[0022] Before a blast furnace is started up and put into operation, most of the tuyeres need to be blocked. This means that air is supplied from multiple tuyeres in the direction of the blast furnace taphole, and air is supplied from other directions at intervals. The blocked tuyeres are gradually cleared according to the blast furnace start-up process. Blast furnace operators use iron storage trough castable, which is prepared with a castable-to-water ratio of approximately 20:1 and thoroughly mixed. Special tuyer blockage bricks are made in advance using tuyer blockage brick making molds according to the inner diameter of the tuyer sleeve. Before starting the furnace and supplying air, remove the air supply pipe of the tuyeres to be blocked. Fill the tuyeres with refractory mortar to a depth of 100mm. Then, use an oxygen blowing pipe or tuyeres blocking rake to pass through the pre-reserved holes in the cast bricks. Send the special brick for blocking the tuyeres into the tuyeres and let it come into contact with the refractory mortar at the front end. Then send more refractory mortar into the tuyeres to form a structure of "refractory mortar + tuyeres blocking brick + refractory mortar" in the entire tuyeres. The overall depth should be 350mm-450mm. After completion, clean the contact surface between the tuyeres and the air supply pipe, and then install the air supply pipe.

[0023] After the blast furnace was started and blast was supplied, the furnace condition was good, and the blast volume was gradually increased. According to the progress, the blast furnace operator planned to use a steel rod to pry open the tuyeres through the inspection hole of the blast pipe. Because the castable bricks for blocking the tuyeres made of castable refractory with Al2O3, corundum, white corundum, silicon carbide, magnesium (dolomite), and bauxite as the main components were suitable in terms of strength and refractoriness, they were not blown open during the blast furnace smelting process. Moreover, the tuyeres were easily pried open by the blast furnace operator when he organized the use of steel rods to pry open the tuyeres, and the tuyeres were successfully supplied with air. Example 2

[0024] During production, a blast furnace encountered a situation where its furnace condition was difficult to restore and the blast was slow for an extended period. In order to increase the blast energy and accelerate the recovery process, the blast furnace operator immediately decided to shut down the blast and block the tuyeres. The blast furnace operator had prepared the iron storage trough castable in advance, mixing it with water at a ratio of approximately 20:1 and stirring it thoroughly. Based on the inner diameter of the tuyere sleeve, they had pre-made special tuyere blocking bricks—castable bricks—using molds and kept them in reserve as daily spare parts. To reduce downtime and facilitate subsequent furnace recovery, the air supply pipe is not removed after downtime. Instead, the inspection port cover of the air supply pipe is removed, and refractory mortar is filled into the tuyer sleeve from the rear end of the air supply pipe to a depth of 100mm. Then, an oxygen blowing pipe or tuyer blocking rake is used to pierce the pre-reserved holes in the cast bricks. The special brick for blocking the tuyer is then sent from the rear end of the air supply pipe into the tuyer sleeve to contact the refractory mortar at the front end. Refractory mortar is then sent into the tuyer sleeve to form a structure of "refractory mortar + tuyer blocking brick + refractory mortar" within the entire tuyer sleeve, with an overall depth of 350mm-450mm being appropriate. After completion, the inspection port cover of the air supply pipe is installed.

[0025] Before the blast furnace resumed blasting and the overall furnace condition was fully restored, the blocked tuyeres were not blown open. Based on the progress of the blast furnace condition restoration, the blast furnace operators planned to use a steel rod to pry open the tuyeres through the inspection hole of the blast pipe. Because the castable bricks for blocking tuyeres made from the castable refractory with Al2O3, corundum, white corundum, silicon carbide, magnesium (dolomite), and bauxite as the main components were suitable in terms of strength and refractoriness, the tuyeres were easily pried open during the process of the blast furnace operators organizing the use of steel rods to pry open the tuyeres, and the tuyeres were able to supply air smoothly.

[0026] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention, as long as they do not depart from the spirit and scope of the technical solution of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A method for manufacturing bricks for blast furnace tuyeres, characterized in that: The manufacturing process includes the following steps: S1. During production, apply a release agent to the brick mold in advance to facilitate demolding; S2, the castable and water are mixed in a certain proportion and stirred evenly, and then poured into the brick mold. The specific formula of the castable is: Al2O3, corundum, white corundum, silicon carbide, magnesium, bauxite, and the ratio of castable to water is 20:

1. S3, before the cast brick dries, insert a solid rod into its center to make a hole in the cast brick; S4. After the castable is completely dry, demold and make the air vent block with bricks. When using the aforementioned air-blocking brick to block the air vent, the air-blocking brick is completely surrounded by refractory mortar. The strength and refractoriness of the bricks used to block the air vents must meet the following conditions: During the blast furnace smelting process, the bricks used to block the tuyeres are prevented from being blown open; During the process of blast furnace operators using steel rods to poke open the tuyeres, the tuyeres can be opened.

2. The method for manufacturing a brick for blast furnace tuyeres according to claim 1, characterized in that: The brick-making mold in S1 is made of wood, hard plastic and steel plate.

3. The method for manufacturing a brick for blast furnace tuyeres according to claim 1, characterized in that: The brick-making mold in S1 is made into a truncated "cone" smaller than the inner diameter of the small sleeve according to the "cone" shape of the small sleeve head, and the diameter of the end face with the larger diameter is smaller than the inner diameter of the small sleeve to prevent the brick from being stuck at the front end of the small sleeve to block the air vent.

4. The method for manufacturing a brick for plugging a blast furnace tuyeres according to claim 1, characterized in that: The diameter of the solid rod in S3 is 15mm-20mm, and the insertion depth is 20mm-25mm.

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