A blast furnace residual iron discharge structure, blast furnace and blast furnace residual iron discharge method

Abstract

The embodiment of the present invention provides a blast furnace residual iron discharge structure, a blast furnace and a method for blast furnace residual iron discharge. The blast furnace residual iron discharge structure includes a furnace body, and the furnace body includes a refractory material layer, a cooling wall and a furnace shell from the inside to the outside in sequence; the furnace shell is provided with an opening corresponding to the preset residual iron discharge position of the furnace body, and the furnace shell is covered with an openable and closable cover part, and the cover part is arranged outward. The furnace body provided by the embodiment of the present invention is provided with a cover part corresponding to the preset residual iron discharge position. When the blast furnace is overhauled, there is no need to cut the furnace shell and weld the furnace shell. The cover part can be directly opened, the cooling wall can be removed and the refractory material layer can be drilled. After the overhaul is completed, the cover part can be closed, and the gap between the cover part and the cooling wall can be poured with refractory material, which reduces the time and possible danger of cutting and welding the furnace shell, shortens the overall blast furnace maintenance time, and improves economic benefits.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgy, and in particular to a blast furnace residual iron discharge structure, a blast furnace and a blast furnace residual iron discharge method. Background Art

[0002] In the field of steel smelting, the blast furnace needs to be shut down for overhaul regularly according to the smelting conditions of the blast furnace, the erosion of the inner wall of the furnace lining, cracks in the furnace shell and other problems. After the blast furnace has produced the last batch of iron and stopped blowing, there is still a large amount of residual molten iron inside the blast furnace. At this time, it is necessary to open a residual iron hole on the furnace shell of the blast furnace, then dismantle the cooling wall, and finally open holes in the internal carbon bricks and other refractory materials to finally release the residual iron inside the furnace. Whether the slag iron in the furnace can be discharged cleanly directly affects the construction progress during the maintenance process. The elevation positioning of the discharge of residual slag iron is an important link in releasing the residual iron. If the elevation is too low, the slag iron may not be released, and it is necessary to open the hole again, increasing the workload. If the elevation is too high, the residual iron in the furnace cannot be discharged cleanly.

[0003] In the prior art, the residual iron mouth is opened after the furnace shell is cut, and the cooling wall is removed and the refractory material is drilled. The speed of any step restricts the progress of the overall blast furnace maintenance. Protective measures should be taken in advance when cutting the furnace shell, because the hot air returning from the cut is very strong when cutting the furnace shell, and the oxygen pressure is very high at the same time. The oxide slag splashed back from the cut can easily burn the human body. It is also necessary to adjust the verticality and distance between the cutting nozzle and the furnace shell. Because the furnace shell plate is thick, the starting point of the furnace shell cut must be fully preheated during cutting to ensure that the cut is thorough. If the cut seam is heated unevenly, the cut seam line will be arc-shaped and not straight during operation, and the cutting speed is not well controlled, which will affect the cutting quality.

[0004] After the blast furnace is repaired, the carbon bricks, cooling walls, etc. need to be restored, and the cut furnace shell also needs to be re-welded. The new furnace shell must strictly follow the size of the "window" opened before. Before welding, the slag and rust spots left around during gas cutting need to be cleaned up. In order to prevent the furnace shell from deforming during welding, certain methods need to be taken to control the deformation of the furnace shell. It is also necessary to select appropriate welding rods, welding currents, etc. according to the material of the furnace shell for welding, so as to ensure the welding quality.

[0005] During the process of cutting and welding the furnace skin, the strength of the furnace skin steel plate in the heat-affected zone is reduced, increasing the risk of cracking in this area during use. Summary of the invention

[0006] The embodiment of the present invention provides a blast furnace residual iron discharge structure, a blast furnace and a blast furnace residual iron discharge method, which are used to solve the problem that the existing method of discharging residual iron by cutting the furnace shell to open a residual iron opening has many disadvantages.

[0007] The embodiment of the present invention provides a blast furnace residual iron discharge structure, comprising a furnace body, wherein the furnace body comprises a refractory material layer, a cooling wall and a furnace skin in sequence from the inside to the outside;

[0008] The furnace shell is provided with an opening corresponding to a preset residual iron placement position of the furnace body, and the opening of the furnace shell is covered with an openable and closable cover member, and the cover member is arranged outward.

[0009] According to the blast furnace residual iron discharge structure according to one embodiment of the present invention, the cover member is a flange door.

[0010] According to the blast furnace residual iron discharge structure of one embodiment of the present invention, the cover member is a square flange door.

[0011] According to a blast furnace residual iron discharge structure of an embodiment of the present invention, the flange door comprises a connecting tube and a flange plate;

[0012] One end of the connecting tube is connected to the furnace shell, and the end of the connecting tube away from the furnace shell is connected to the flange. The end cover covers the end of the connecting tube away from the furnace shell. The end cover and the flange are connected by a screw connection. The sealing ring is arranged between the end cover and the flange.

[0013] The end cover is penetrated by a filling hole communicating with the connecting tube.

[0014] According to a blast furnace residual iron discharge structure of an embodiment of the present invention, the end cover is provided with exhaust holes and pouring holes inside the upper and lower edges of the connecting tube, at least one pouring hole and one exhaust hole are provided, and the pouring hole and the exhaust hole are provided with valves, and the valves are closed after the pouring is completed. During the pouring process, when the pouring material is observed to emerge from the exhaust hole, the pouring is completed, and then the valve is closed.

[0015] According to the residual iron discharge structure of a blast furnace according to an embodiment of the present invention, a plurality of the screw connections are provided along the circumference of the end cover, and the plurality of the screw connections are located at the periphery of the plurality of the pouring holes.

[0016] According to the blast furnace residual iron discharge structure according to one embodiment of the present invention, the connecting tube is arranged to extend horizontally.

[0017] According to the residual iron discharge structure of a blast furnace according to an embodiment of the present invention, pouring is performed between the cover member and the cooling wall.

[0018] According to a blast furnace residual iron discharge structure of an embodiment of the present invention, the cooling wall comprises a first section cooling wall and a second section cooling wall, and the cover member is arranged corresponding to the first section cooling wall and the second section cooling wall.

[0019] An embodiment of the present invention further provides a blast furnace, comprising the blast furnace residual iron discharge structure as described above.

[0020] The embodiment of the present invention also provides a method for discharging residual iron in a blast furnace, comprising:

[0021] Open the cover and determine the best position for placing residual iron;

[0022] The cooling wall at the optimal residual iron discharge position is removed, and holes are drilled in the refractory layer to discharge the residual molten iron in the furnace body;

[0023] After the residual iron is released, repair the refractory material, install the cooling wall, close the cover, and pour the refractory material into the gap between the cover and the furnace shell. Close the valve when the pouring material is observed to come out of the exhaust hole.

[0024] The furnace body provided in the embodiment of the present invention is provided with a covering part corresponding to the preset residual iron placement position. When the blast furnace is overhauled, there is no need to cut the furnace lining and weld the furnace lining. The covering part can be directly opened, the cooling wall can be removed and the refractory material layer can be drilled. After the overhaul is completed, the covering part can be closed and the refractory material can be poured into the gap between the cooling wall and the furnace lining, which reduces the time and possible dangers of cutting and welding the furnace lining, shortens the overall blast furnace maintenance time, and improves the economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a structural schematic diagram of a blast furnace residual iron discharge structure provided by an embodiment of the present invention;

[0027] Figure 2 yes Figure 1 Schematic diagram of the structure at the middle cover.

[0028] Reference numerals:

[0029] 100: blast furnace residual iron discharge structure; 1: furnace body; 11: refractory material layer; 12: cooling wall; 13: furnace skin; 2: cover; 21: connecting tube; 22: flange; 23: end cover; 24: pouring hole; 3: screw connection. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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. 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.

[0031] The embodiment of the present invention provides a blast furnace residual iron discharge structure, such as Figure 1 and Figure 2 As shown, the blast furnace residual iron discharge structure 100 includes a furnace body 1 and a cover member 2.

[0032] like Figure 1 As shown, the furnace body 1 includes a refractory layer 11, a cooling wall 12 and a furnace shell 13 from the inside to the outside, and the furnace shell 13 is provided with an opening corresponding to the preset residual iron placement position of the furnace body 1. In the design of the existing blast furnace, the position of the residual iron opening is pre-set on the furnace body 1, and the preset residual iron placement position is the position of the residual iron opening pre-set on the furnace body 1. Specifically, the cooling wall 12 includes a first section of the cooling wall and a second section of the cooling wall, and the preset residual iron placement position is usually located at the first section of the cooling wall and the second section of the cooling wall. The opening of the furnace shell 13 corresponds to the preset residual iron placement position, which usually means that the opening of the furnace shell 13 covers the preset residual iron placement position.

[0033] like Figure 1 and Figure 2 As shown, the cover at the opening of the furnace shell 13 is provided with an openable and closable cover member 2, and the cover member 2 is arranged outward. The furnace shell 13 is provided with an openable and closable cover member 2. By opening the cover member 2, the relative position of the cooling wall 12 and the cover member 2 can be exposed to the outside (in this embodiment, the cover member 2 is arranged corresponding to the first section of the cooling wall and the second section of the cooling wall). In this way, when the blast furnace is overhauled, it is not necessary to cut the furnace shell 13 and weld the furnace shell 13. The cover member 2 is directly opened, the cooling wall 12 is removed, and the refractory material layer 11 is drilled. After the overhaul is completed, the cover member 2 is installed, and the space between the cover member 2 and the cooling wall 12 is perfused through the holes reserved in advance on the cover member 2 (the space between the furnace shell 13 and the cooling wall 12 is also filled with perfusion liquid), which reduces the time and possible danger of cutting and welding the furnace shell 13, shortens the overall blast furnace maintenance time, and improves economic benefits.

[0034] The furnace body 1 provided in the embodiment of the present invention is provided with a covering member 2 corresponding to the preset residual iron placement position. When the blast furnace is overhauled, there is no need to cut the furnace cladding 13 and weld the furnace cladding 13. The covering member 2 can be directly opened, the cooling wall 12 can be removed, and the refractory material layer 11 can be drilled. After the overhaul is completed, the covering member 2 can be closed, which reduces the time and possible dangers of cutting and welding the furnace cladding 13, shortens the overall blast furnace maintenance time, and improves the economic benefits.

[0035] The cover member 2 may be a flange door, etc. For example, in this embodiment, the cover member 2 is a square flange door. Figure 1As shown, in this embodiment, the flange door includes a connecting tube 21, a flange 22, an end cover 23 and a sealing ring; one end of the connecting tube 21 is connected to the furnace shell 13, and the end of the connecting tube 21 away from the furnace shell 13 is connected to the flange 22, and the end cover 23 covers the end of the connecting tube 21 away from the furnace shell 13, and the end cover 23 and the flange 22 are connected by a screw connection 3, and the sealing ring is arranged between the end cover 23 and the flange 22 (the sealing ring can be asbestos, ceramic fiber wool, graphite gasket, etc., and the use temperature of the sealing ring is greater than 150°C); the end cover 23 is penetrated by a perfusion hole 24 connected to the connecting tube 21. Perfusion can be performed through the perfusion hole 24 to achieve a sealing effect. Among them, the connecting tube 21 is usually arranged to extend horizontally.

[0036] In this embodiment, the end cap 23 is provided with an exhaust hole and a pouring hole 24 inside the upper and lower edges of the connecting tube 21, at least one pouring hole 24 and one exhaust hole are provided, and the pouring hole 24 and the exhaust hole are provided with valves, and the valves are closed after the pouring is completed. During the pouring process, when the pouring material is observed to come out from the exhaust hole, the pouring is completed, and then the valve is closed.

[0037] like Figure 1 As shown, in this embodiment, the flange 22 is inclined, and the flange 22 is inclined along the angle of the furnace shell 13 .

[0038] The screw connection 3 and the injection hole 24 are usually provided with a plurality of Figure 1 As shown, the end cover 23 is provided with a plurality of injection holes 24 ; a plurality of screw connectors 3 are provided along the circumference of the end cover 23 , and the plurality of screw connectors 3 are located outside the plurality of injection holes 24 , for example, two injection holes 24 are provided at intervals in the upper and lower directions.

[0039] An embodiment of the present invention further provides a blast furnace, which includes the blast furnace residual iron discharge structure as described above.

[0040] The embodiment of the present invention further provides a method for discharging residual iron in a blast furnace, comprising the following steps:

[0041] Step S110, opening the cover and determining the best position for placing residual iron.

[0042] Specifically, when placing the residual iron, the cover is opened, and a combination of theoretical calculation method, furnace shell surface temperature measurement method and carbon brick surface temperature measurement method is used to find the residual iron mouth elevation and determine the best residual iron placement position.

[0043] Step S120, dismantling the cooling wall at the best residual iron release position, and drilling holes in the refractory layer to release the residual molten iron in the furnace body.

[0044] Step S130, after the overhaul is completed, the cover is closed and the space between the cover and the cooling wall is poured.

[0045] For example, if the cover is a flange door, after the overhaul is completed, the flange door is directly installed, the nut is tightened, and the area between the cooling wall and the flange door is poured through the pouring holes pre-set on the flange door.

[0046] Optionally, after the residual iron is released, the refractory layer is repaired, the cooling wall is installed, the cover is closed, and the gap between the cover and the furnace shell is poured with refractory material. When the pouring material is observed to come out from the exhaust hole, the pouring is completed and then the valve is closed.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A blast furnace residual iron discharge structure, characterized in that: The furnace body comprises a refractory material layer, a cooling wall and a furnace skin in sequence from the inside to the outside; The furnace shell is provided with an opening corresponding to a preset residual iron placement position of the furnace body, and the opening of the furnace shell is covered with an openable and closable cover member, and the cover member is arranged outward; The sealing member is a flange door; The flange door comprises a connecting tube, a flange, a sealing ring and an end cover; One end of the connecting tube is connected to the furnace shell, and the end of the connecting tube away from the furnace shell is connected to the flange. The end cover covers the end of the connecting tube away from the furnace shell. The end cover and the flange are connected by a screw connection. The sealing ring is arranged between the end cover and the flange. The end cover is provided with a perfusion hole communicating with the connecting tube; Refractory material is poured between the cover and the cooling wall; The cooling wall comprises a first section cooling wall and a second section cooling wall, and the cover member is arranged corresponding to the first section cooling wall and the second section cooling wall.

2. The blast furnace residual iron discharge structure according to claim 1, characterized in that: The sealing cover is a square flange door.

3. The blast furnace residual iron discharge structure according to claim 1, characterized in that: The end cover is provided with a plurality of the injection holes; A plurality of the screw connectors are arranged along the circumference of the end cover, and the plurality of the screw connectors are located at the periphery of the plurality of the injection holes.

4. The blast furnace residual iron discharge structure according to claim 1, characterized in that: The connecting tube is arranged to extend horizontally.

5. A blast furnace, characterized in that: It comprises the blast furnace residual iron discharge structure as described in any one of claims 1 to 4.

6. A method for discharging residual iron in a blast furnace, applicable to the residual iron discharging structure for a blast furnace as claimed in any one of claims 1 to 4, characterized in that: include: Open the cover and determine the best position for placing residual iron; The cooling wall at the optimal residual iron discharge position is removed, and holes are drilled in the refractory layer to discharge the residual molten iron in the furnace body; After the residual iron is released, repair the refractory layer, install the cooling wall, close the cover, and pour refractory material into the gap between the cover and the furnace shell. Close the valve when the pouring material is observed to come out of the exhaust hole.

Images