Blowing-in sleeper filling method for giant blast furnace

Abstract

The invention discloses a filling method of a giant blast furnace blow-in sleeper, which comprises the following steps of: controlling the quantity and the granularity of bottom coke and matching with the requirements of the material, the shape and the filling mode of the sleeper, the protection mode of a tuyere area and the shape of a center stack tip; mechanical protection of a tuyere area can be achieved, materials on the upper portion can be fully heated, the materials slowly and evenly descend, a hearth is fully heated, the liquidity of liquid slag iron is good, it can be guaranteed that the liquidity of primary iron is appropriate, and slag iron is smoothly separated. The method aims at solving the problems that in the blow-in process, the sleeper filling rate is too low, materials on the upper portion decline unevenly, a tuyere is prone to damage, and the primary iron fluidity is difficult to guarantee.

Description

Technical Field

[0001] The invention relates to a method for filling open-furnace sleepers for a giant blast furnace. Background Art

[0002] Before a newly built blast furnace is started, the entire furnace must be loaded. First, the furnace needs to be loaded. Generally, bottom coke is added to the bottom of the furnace, and then sleepers are filled on the bottom coke. Sleepers have a low ignition point and are easy to ignite. In addition, sleepers have the advantage of extremely low ash content. After being ignited, the sleepers can quickly heat the coke on them, thereby achieving rapid furnace start-up and effectively reducing the [Si] content in molten iron and improving the initial iron fluidity. However, if there are no relevant constraints on the arrangement and loading methods of sleepers, it is easy to have a low furnace filling rate, difficulty in quickly forming the central airflow, and even rapid collapse of the sleepers after ignition, resulting in poor upper preheating, rapid drop of materials to the furnace, insufficient furnace temperature, and poor fluidity of the generated slag iron, which will make it difficult to tap the first iron and interfere with subsequent strengthening. Summary of the invention

[0003] The purpose of the present invention is to provide a method for filling sleepers for a giant blast furnace, which is used to solve the problems of low sleeper filling rate, uneven drop of upper materials, easy damage of tuyere and difficulty in ensuring initial iron fluidity that are easy to occur during the furnace opening process.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The present invention discloses a method for filling sleepers for a giant blast furnace, comprising:

[0006] Working conditions: The temperature in the blast furnace drops below 40℃, the gas composition in the furnace is tested and ready for entry, the furnace top equipment test run is stopped, the large manhole on the furnace top is opened and supervised by a dedicated person, the nitrogen of the furnace top distributor, the nitrogen of the camera, and the nitrogen of the probe are all stopped, the furnace top venting is opened, and the air supply branch pipe is equipped with a blind plate;

[0007] Control of the amount of bottom coke: Use coke to lay the bottom, and ensure that the thickness of the furnace bottom is controlled within 600-1000mm;

[0008] Control of bottom coke particle size: use normal particle size coke or small particle size coke <25mm;

[0009] Requirements for laying bottom coke: After loading the bottom coke from the furnace top, it should be leveled manually to prevent the top surface of the coke from being uneven and to prevent the sleepers from falling unevenly in the circumferential direction;

[0010] Selection of sleeper materials: Rotten wood cannot be used for processing, oil-free wood is required, and it must be air-dried vertically before leaving the factory. The average density after natural drying must be 780-820Kg / m3;

[0011] Selection of sleeper size: long sleeper: 2.5m long × 0.2m wide × 0.16m high; short sleeper: (0.8-1.0)m long × 0.2m wide × 0.16m high;

[0012] The number of sleepers to be selected: determined by the filling area of ​​the furnace;

[0013] Sleeper shape control: No positive tolerance is allowed in the dimensions;

[0014] Loading and stacking of sleepers: sleepers are loaded from the tuyere in bulk, which can greatly save time. Short sleepers are used to fill the furnace body. Smaller size can improve the filling rate of the furnace. When the distance from the center line of the tuyere is 600mm, they are no longer loaded in bulk. Sleepers are laid closely in the same direction to ensure that the gap between sleepers in the same direction is less than 30mm. Three layers of short sleepers are laid closely.

[0015] Tuyere protection: Long sleepers are stacked close to the furnace wall in front of the tuyere to protect the tuyere, and nails are used to fix the long sleepers;

[0016] Center pile tip: Use long and short sleepers to build a conical center pile tip with a diameter of 3m and a height of 2.5m; requirements: the center of the bottom surface of the pile tip coincides with the center point of the furnace, and all the sleepers used to construct the outside of the cone are fixed with nails.

[0017] Furthermore, the sleepers are made of hard wood that matures quickly and is inexpensive.

[0018] Furthermore, the sleeper material is coconut wood.

[0019] Furthermore, the sleeper filling volume V is the volume of the furnace below the center line of the tuyere excluding the bottom coke.

[0020] Furthermore, each tuyere is protected by 6 long sleepers, which are arranged in one layer and fastened to each other with nails.

[0021] Compared with the prior art, the beneficial technical effects of the present invention are:

[0022] The present invention controls the amount and particle size of the bottom coke, matches the material, shape, and filling method of the sleepers, the protection method of the tuyere area, and the requirements of the center pile tip shape, so that the mechanical protection of the tuyere area can be achieved, the upper material can be fully heated, the material can descend slowly and evenly, the furnace hearth can be fully heated, the liquid slag iron has good fluidity, the first iron can ensure appropriate fluidity, and the slag iron can be separated smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] Figure 1 This is the volume segmentation diagram of the filled sleeper part. DETAILED DESCRIPTION

[0025] A 4000m 3 The method for filling sleepers during the above blast furnace opening process includes:

[0026] Working conditions required: the temperature inside the blast furnace drops below 40℃, the gas composition in the furnace is tested and ready for entry, the furnace top equipment test run is stopped, the large manhole on the furnace top is opened and supervised by a dedicated person, the nitrogen for the furnace top distributor, the nitrogen for the camera, and the nitrogen for the probe are all stopped, the furnace top venting is opened, and the air supply branch pipe is equipped with a blind plate.

[0027] Control of the amount of bottom coke: Use coke to lay the bottom to ensure that the thickness at the bottom of the furnace is controlled at 600-1000mm.

[0028] Control of bottom coke particle size: use ordinary particle size coke or small particle size coke <25mm.

[0029] Requirements for laying bottom coke: After the bottom coke is loaded from the furnace top, it must be raked level manually to prevent the top surface of the coke from being uneven and to prevent the sleepers from descending unevenly in the circumferential direction.

[0030] Selection of sleeper materials: sleepers can be made of fast-growing, cheap hardwood (such as coconut wood), rotten wood cannot be used for processing, and must be oil-free. They must be air-dried before leaving the factory, and the average density after natural drying must be 800Kg / m 3 about.

[0031] Sleeper size selection: long sleeper (length, width and height): 2.5m×0.2m×0.16m; short sleeper (length, width and height): (0.8-1.0)m×0.2m×0.16m;

[0032] Selection of the number of sleepers: determined by the filling area of ​​the furnace.

[0033] Sleeper shape control: No positive tolerance is allowed in dimensions.

[0034] Loading and stacking of sleepers: sleepers are loaded through the tuyere in bulk, which can greatly save time. Short sleepers are used to fill the furnace body. The smaller size can increase the filling rate of the furnace. When the sleepers are filled to 600mm from the center line of the tuyere, they are no longer loaded in bulk. The sleepers are densely laid in the same direction to ensure that the gap between sleepers in the same direction is less than 30mm. Three layers of short sleepers are densely laid.

[0035] Tuyere protection: Long sleepers are stacked close to the furnace wall in front of the tuyere to protect the tuyere, and the long sleepers are fixed with nails.

[0036] Center pile tip: Use long and short sleepers to build a conical center pile tip with a diameter of 3m and a height of 2.5m. Requirements: The center of the bottom of the pile tip coincides with the center point of the furnace, and all the sleepers used to build the outside of the cone are fixed with nails.

[0037] like Figure 1 As shown:

[0038] A. Confirm the sleeper filling volume V (the volume of the furnace below the center line of the tuyere excluding the volume of the bottom coke);

[0039] V=V1+V2+V3+V4+V5+V6+V7-bottom coke volume;

[0040] V1=310.05m 3 V2=75.36m 3 V3=130.17m 3 V4=91.95m 3 ;

[0041] V5=48.05m 3 V6=196.94m 3 V7=113.98m 3 ;

[0042] Bottom coke volume = 119m 3 ;

[0043] Therefore, the volume filled with sleepers is V = 847m 3 ;

[0044] B. Confirm the volume of the central pile tip

[0045] Vpile = 3.14 × (3 / 2)2 × 2.5 × 1 / 3 = 5.89 m 3 ;

[0046] C. Number of long sleepers for tuyere protection

[0047] Each tuyere is protected by 6 long sleepers, divided into one layer and fastened together with nails;

[0048] 38×6=228 roots, take 230 roots;

[0049] D. Determination of sleeper quantity:

[0050] Specifications 0.8-1.0m×0.2×0.16m: 0.5×V=0.5×847=424m 3 ;

[0051] Specifications 2.5×0.2×0.16m: 2.5×0.2×0.16m×230=19m 3 .

[0052] The present invention can achieve mechanical protection of the tuyere area by controlling the amount and particle size of the bottom coke, in conjunction with the material, shape, and filling method of the sleepers, the protection method of the tuyere area, and the requirements of the center pile tip shape, so that the upper material can be fully heated, the material can descend slowly and evenly, the furnace hearth can be fully heated, the liquid slag iron has good fluidity, the first iron can ensure appropriate fluidity, and the slag iron can be separated smoothly.

[0053] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for filling sleepers for a giant blast furnace, characterized in that: include: Working conditions: The temperature in the blast furnace drops below 40℃, the gas composition in the furnace is tested and ready for entry, the furnace top equipment test run is stopped, the large manhole on the furnace top is opened and supervised by a dedicated person, the nitrogen of the furnace top distributor, the nitrogen of the camera, and the nitrogen of the probe are all stopped, the furnace top venting is opened, and the air supply branch pipe is equipped with a blind plate; Control of the amount of bottom coke: Use coke to lay the bottom, and ensure that the thickness of the furnace bottom is controlled within 600-1000mm; Control of bottom coke particle size: use normal particle size coke or small particle size coke <25mm; Requirements for laying bottom coke: After loading the bottom coke from the furnace top, it should be leveled manually to prevent the top surface of the coke from being uneven and to prevent the sleepers from falling unevenly in the circumferential direction; Selection of sleeper materials: Rotten wood cannot be used for processing, oil-free wood is required, and it must be air-dried vertically before leaving the factory. The average density after natural drying must be 780-820Kg / m3; Selection of sleeper size: long sleeper: 2.5m long × 0.2m wide × 0.16m high; short sleeper: (0.8-1.0)m long × 0.2m wide × 0.16m high; The number of sleepers to be selected: determined by the filling area of ​​the furnace; Sleeper shape control: No positive tolerance is allowed in the dimensions; Loading and stacking of sleepers: sleepers are loaded from the tuyere in bulk, which can greatly save time. Short sleepers are used to fill the furnace body. Smaller size can improve the filling rate of the furnace. When the distance from the center line of the tuyere is 600mm, they are no longer loaded in bulk. Sleepers are laid closely in the same direction to ensure that the gap between sleepers in the same direction is less than 30mm. Three layers of short sleepers are laid closely. Tuyere protection: Long sleepers are stacked close to the furnace wall in front of the tuyere to protect the tuyere, and nails are used to fix the long sleepers; Center pile peak: Use long and short sleepers to build a conical center pile peak with a diameter of 3m and a height of 2.5m; Requirements: The center of the bottom surface of the pile tip should coincide with the center point of the furnace, and all the sleepers used to construct the outside of the cone should be fixed with nails.

2. The method for filling sleepers for a giant blast furnace according to claim 1, characterized in that: The sleepers are made of hard wood that matures quickly and is cheap.

3. The method for filling sleepers for giant blast furnace according to claim 1 or 2, characterized in that: The sleeper material is coconut wood.

4. The method for filling sleepers for a giant blast furnace according to claim 1, characterized in that: The sleeper filling volume V is the volume of the furnace below the center line of the tuyere excluding the bottom coke.

5. The method for filling sleepers for a giant blast furnace according to claim 1, characterized in that: Each air vent is protected by 6 long sleepers, which are arranged in one layer and fastened together with nails.

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